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Role of the Planning Engineer

The estimating team will consider construction methods and employ planning techniques to:

1. Highlight any critical or unusual activities.
2. Examine alternative ways of tackling the work.
3. Calculate optimum durations for temporary works and plant.
4. Reconcile the labour costs in the estimate with a programme showing resources.
5. Determine the general items and facilities priced in the preliminaries section of the bill.
6. Check whether the time for completion is acceptable.

The effort needed will depend on the size and complexity of the project, the proposed use of heavy plant and the design of major temporary works. Estimating for civil engineering work in particular is dependent on an examination of alternative methods and pre-tender programmes. A civil engineering estimator usually produces a resourced programme to price major aspects of the work operationally.

Pre-tender programmes are prepared by either the estimator or planning engineer, or more likely by working together.The choice depends on company policy, size of project and type of work. The planning engineer’s contribution can be seen as producing an appraisal of labour and plant resources and general items – in other words the estimator expresses his solutions in terms of cash, the programmer deals with time. The aim is to reconcile one with the other.

In a competitive market it is important to look for ways to construct the project more economically. Applying planning techniques can have opposite consequences. Increasing the value of the tender when problems are identified and reducing the estimate when methods can be adopted which reduce individual and overall durations. The team must, however, look for the solution, which reflects the ‘true’ cost of construction.The role of the planning engineer is wider than just producing a programme. His input to a tender can also include:

1. Producing site layout drawings, which are used to locate temporary facilitates, such as concrete batching plant, cranage, access routes, restrictions, areas for accommodation and storage, location of services, overhead service, temporary spoil heaps, and areas which will need reinstatement.
2. Examining the most suitable methods in relation to the design and the temporary works required.
3. Preparing method statements not only for pricing purposes but also for submission to clients or consultants when requested.
4. Producing cashflow forecast charts for management and clients who need them.
5. Providing staff structure and resource histograms for general labour, production labour and plant.

The planning engineer will often have a better understanding of current site practice and will be better placed to collect data from monitoring exercises on site. His experience of completed work will be important especially where the overall duration of a project could be reduced. Shorter contract periods can have a substantial effect on the cost of preliminaries where time-related costs (mainly staff, site accommodation, cranage and scaffolding) account for as much as 12–20% of a tender figure.

5 Handy Tips for Anyone Starting an Engineering Business

6:00 AM Civil Engineering , Construction Management , General , Project Management

If you have decided to start an engineering business, you are about to embark on an exciting journey into the unknown. Working for yourself is different to working for a boss. You are now the master of everything you do. You decide what happens to you and how much money you make. For some, that freedom is liberating, for others, it is terrifying. Becoming a boss won’t be easy. You have loads of things to consider before you make it big. Here are five super tips that you should keep in mind.

Make a financial budget before every quote

When you get your first job, it is easy to let it excite you. Many new businessmen rush into quoting people for a job, before doing their research. Don’t think that taking a little extra time to complete your budget will lose you a client. Many people worry that if they take too long getting back to the client, the client will go with another company. It is your duty to make a budget before you set a quote. If you don’t do that, you could end up losing money on jobs.

Time management will be your best tool

Engineering jobs always run longer than they should. You can set yourself aside from the majority of engineering companies by completing jobs on time. Time management is not easy. You need to have great organizational and planning skills. You should make sure that you make a detailed schedule of each day. That means you can plan everybody’s roles and responsibilities before they start work. Usually, engineering companies get just one fee for the entire job. That means that when you are wasting time, you’re also wasting money.

Every employee plays an integral role

Don’t dismiss anyone’s ability or skills. In an engineering company, there is a hierarchy system that works within every group. There is no such thing as a small job. Make sure that you appreciate the hard work that everybody is putting into your company. It is vital that you let your staff know how much you appreciate them. It can be easy to take staff for granted. If you do that, your staff will likely find another company for which to work. Take the time to get to know your staff so that you create a strong working relationship with them.

Choose your material and tools with care

When you are buying your materials and tools for each job, you might find buying the cheapest items is tempting. Remember, cheap materials never last. You want people to remember you as a quality company. That means that you need to ensure that you get quality materials so that they last. For example, when you’re buying a drawn seamless tube for a job, make sure that it comes with great reviews. Finding the right material for each job is vital to the success of your business, and so you need to make sure that you choose with care.

Start small and think big later

You might want to dive into large engineering jobs and take on the world. As with everything, though, you’re going to need to start small. You can’t expect to land a massive job when you first start your business. Your clients want to see a track record of great work from you. That means that you won’t get the big jobs until you have proved you can handle them. No job is ever too small for you to take on when you start your company. Thinking that you’re above certain jobs won’t win you friends or clients. Take any job you can get so that you can start building your portfolio.

Quality Requirements of Pumped Concrete

2:45 PM Civil Engineering , Concrete , Construction Management , Construction Materials

Pumped concrete can be used for most structural concrete construction but is most useful where space for construction equipment is limited or access is difficult. Concrete pumps can be either truck- or trailer mounted and range from small units, exerting pressures from 250 to 300 psi and outputs of 15 to 30 yd³/hr, to large units, exerting pressures of 1,000 psi and outputs up to 150 yd³. The effective capacity of a pump depends not only on the pump itself but also on the complete system. Several factors including line length, number of bends in the line, type of line, size of line, height to which the concrete is being pumped, and the concrete mixture affect the effective working capacity of a concrete pump. An excellent reference is ACI 304.2R.

1. Pump lines

Pump lines are usually a combination of rigid pipe and heavy-duty flexible hose. Acceptable rigid pipe can be made of steel or plastic and is available in sizes from 3 to 8 in. in diameter. Aluminum alloy pipe should not be used as pump line. Flexible hose is made of rubber, spiral wound flexible metal, and plastics. It is useful in curves, difficult placement areas, and as connections to moving cranes but exhibits greater line resistance to the movement of concrete than rigid pipe and may have a tendency to kink. To obtain the least line resistance, the pipeline should be made up primarily of rigid pipe with flexible hose only where necessary. If possible, the pipeline should be of one size and laid out so as to contain a minimum number of bends.

2. Mixture proportions

Concrete mixture proportions of pumpable mixtures are essentially the same as those to be placed by other methods, except that more emphasis should be placed on the grading of the fine aggregates. Concretes which are pumped must be cohesive. Harsh mixtures do not pump well. Pressure exerted by the pump can force the mortar away from the coarse aggregate causing a blockage in the line if the mixture is not proportioned properly. The cement content will generally be somewhat higher for pumped mixtures than those of mixtures placed by conventional methods. The higher fine aggregate content will have a higher water demand, which in turn will require higher cement content. However, extra cement should not be used to correct pumping deficiencies resulting from poorly graded aggregates. It is usually more preferable to correct deficiencies in the fine aggregates by blending in additional fine aggregates or pozzolana than by adding cement.

3. Coarse aggregates

The nominal maximum size of the coarse aggregate is limited to one-third of the smallest inside diameter of the pump line for crushed aggregates or 40 percent of the smallest inside diameter of the pump line for well-rounded aggregates. Oversize particles should be eliminated. Higher mortar content will be necessary to effectively pump a concrete containing crushed aggregates than for a concrete containing rounded aggregates. Depending upon the type and size of the coarse aggregate, it may be necessary to reduce the coarse aggregate content from 5 to 10 percent as compared to mixtures placed by conventional methods.

4. Fine aggregate

The properties of fine aggregates are more critical in proportioning pumpable mixtures than are the properties of the coarse aggregates. Together with the cement and water, the fine aggregates constitute the mortar which conveys the coarse aggregates in suspension through the pump line. Fine aggregates should conform to the requirements given in ASTM C 33 for fine aggregates. In addition, for pump systems having lines 6-in. in diameter and smaller, 15 to 30 percent of fine aggregate should pass the 300-μm (No. 50) sieve and 5 to 10 percent should pass the 150-μm (No. 100) sieve. Fine aggregates that are deficient in either of these two sizes should be blended with selected finer aggregates to produce the desired grading. Pumpability of concrete is generally improved with a decrease in the fineness modulus. Fine aggregates having a fineness modulus between 2.40 and 3.00 are generally satisfactory provided that the percentages passing the 300- and 150-μm (No. 50 and No. 100) sieves meet the previously stated guidelines. Fineness modulus values alone without stipulations on the finer sizes may not produce satisfactory results. Both manufactured fine aggregates and natural sands can be used in pumped mixtures provided their gradings are appropriate; however, natural sands are preferred due to their rounded shape.

5. Slump

The water requirements to establish the optimum slump and to maintain control of that slump throughout the course of a pumping placement are both extremely important factors. Concretes having slumps less than 2 in. when delivered to the pump are difficult to pump. Concretes having slumps over 6 in. can segregate causing a blockage in the pump line and may require a pump aid to increase the cohesiveness of the concrete to prevent the aggregate from separating from the mortar during pumping.

It is much more important to obtain a cohesive concrete through proper proportioning than to try to overcome deficiencies by adding extra water. In fact, the use of excess water creates more problems than it solves.

6. Admixtures

Materials which improve workability, such as water-reducing, high-range water-reducing, and air-entraining admixtures, as well as pozzolanas, usually improve pumpability. It is common to experience a decrease in air content during pumping. The specified air contents required for durability should be obtained at the point of placement in the structure. Therefore, it may be necessary to entrain a higher air content into the concrete mixture prior to pumping. Pumping aids are admixtures which can reduce friction, reduce bleeding, and increase cohesiveness, all of which make concretes pump easier.

7. Pump-ability tests

There is no standard laboratory test method available to accurately test the pumpability of a concrete mixture. Testing a concrete mixture for pumpability involves duplicating anticipated job conditions from beginning to end. A full-scale field test for pumpability should be considered to evaluate both the mixture proportions and pumping equipment. Prior use of a mixture and pumping equipment on another job may furnish evidence of pumpability if job conditions are duplicated.

8. Planning

Proper planning of the entire pumping operation including pump location, line layout, placing sequence, and concrete supply will result in savings of time and expense. The pump should be as near the placement area as possible. Concrete delivery systems should have easy access to the pump. Lines from the pump to the placement area should be made up primarily of rigid pipe and contain a minimum number of bends. For large placement areas, alternate lines should be laid for rapid connection when required, and standby power and pumping equipment should be readily available to replace an initial piece of equipment should a breakdown occur.

Other requirements

When pumping downward 50 ft or more, an air release valve at the middle of the top bend will prevent vacuum or air buildup. When pumping upward, a shutoff valve near the pump will prevent the reverse flow of concrete during the fitting of cleanup equipment or when working on the pump. Direct communication should be maintained between the placing crew and the pump operator. Good communication between the pump operator and the concrete batch plant is also important. It is desirable to have the concrete delivery such that the pumping can proceed continuously. When a delay occurs, it may be difficult to start the concrete moving in the line again, especially if the delay has been for a considerable length of time. This critical delay time will depend upon such factors as the concrete mixture, temperature, length of pipeline, and type of pump. It may be necessary to clean the line and start again if the delay becomes extended. A grout or mortar should be used to lubricate the pipeline anytime pumping is started with clean lines, but it should not be pumped into the forms.

Quality verification

A high level of quality control must be maintained to provide assurance that the concrete is of the desired quality. Concrete should be sampled at both ends of the pumpline to determine what, if any, changes in the slump, air content, and other concrete properties occur during pumping. However, the quality of the concrete being placed in the structure can only be measured at the placement end of the pumpline.

5 Signs You Should Invest in Construction Industry

9:59 AM Civil Engineering , Construction Management

The 2008 slowdown brought a crushing time for many construction companies. Recession forced many construction contractors to look for alternatives, as the industry became too slow to grow. The housing slump together with slugging consumer expenditure on their house led to one of the most tormented times for the construction industry.
However, the bad days are history now. With spending on commercial and residential construction renovation, and restoration on the upsurge, construction contractors are hoping to cash in. But there must be caution while committing new investment. You must ensure that problems are few and growth prospects are not tardy. The following are the five most important points to consider before making investment in construction.

You have enough cash

Investing in construction requires a lot of money, as the industry is financial intensive. And considering an investment without adequate cash is not a good thought. Construction companies must not borrow too heavily for investments. The cash reserve must be tapped instead of creating added financial liabilities. So, you must have a good chunk of financial resources prior to considering investment.
But having enough cash is not the sole criteria for investment. It just set the ball rolling in that direction. Construction contractors and companies should look out for adequate and favorable opportunities based on their experience, expertise, and business intelligence.

5 Signs You Should Invest in Construction Industry

Image courtesy: dlfinancehouse.com

Market in your favor

Right time is a factor in reaping profits from all kinds of investment and the construction companies are no exception to it. Unless the market is poised to grow, expand, and bring profits, the investment may not be rewarding. So make sure the market in your favor before making an investment in construction.
To identify whether the market is favorable, construction companies or general contractors need to keep a tab on trends and news related to their industry. Check what types of conditions prevail in your city, state, and country. Make a thorough review of problems galloping the construction industry and try to figure out its prospects in the future. Publications by organizations, associations, and agencies related to the construction industry come handy in identifying opportunities.

Got a project with assured profit

Assured profit is key indicator and enticement for investment. Construction companies and contractors working on a project with guaranteed profit must not be hesitant to invest in men, material, and technology if required. The biggest benefit here is that you know you are going to draw a handsome profit over your investment and this empowers you to make decision on investing.
However, cautious investment is required rather than an outright decision. Construction companies and contractors must calculate overall benefit from the project and invest keeping the return in consideration. Avoid making a huge investment that may decimate the profit viability. Instead, go for a piecemeal approach and invest as you progress keeping a tab on the need vis-à-vis the profit.

Neighborhood infrastructure boost

The increased public and private expenditure in infrastructure has a correlation with the construction industry. Wherever there is an increase in infrastructure spending, the construction businesses have opportunities. Be it housing, road and bridges, or public works, an investment by the government or private sectors create jobs for construction companies, construction contractors, general contractor, and renovation contractors. And you must be ready to invest in your business so that you can acquire and complete projects of any scale.
No doubt infrastructure spending brings in opportunities for the construction industry both in direct and indirect form. But, remember, there is cut-throat competition and you have all your resources ready to beat the heat and get a contract. You must keep an eye on prospective industry news, policy decisions, and even potential projects in the offing and prepare yourself accordingly.

You need to adopt new practices

Today’s construction industry has become tech-savvy and construction companies cannot overlook it. Right from making advertisements, promotions, sending proposals, and bidding to project management, collaboration, and implementation, and customer communication, new practices are being progressively incorporated into the construction industry. These new tools and practices are not only helpful in saving costs, better showcase of designs and previous works, preventing delays, budget overruns, and wastage, but also useful in portraying construction contractors in a credible way.

Identify the area of investment and then find out the rationale of such an investment considering the market conditions and growth prospects. Avoid too much financial liabilities that may choke your viability as a construction business. Be cautious in evaluating new opportunities and analyze the ways to garner maximum benefit out of the investment.

An Insight into Frames Infilled with Masonry

9:16 PM Civil Engineering , Construction Management , structures

A masonry infilled reinforced concrete frame

The infilled frame consists of a steel or reinforced concrete column-and-girder frame with infills of brickwork or concrete block work. In addition to functioning as partitions, exterior walls and walls around stair, elevator and service shafts, the infills may also serve structurally to brace the frame against horizontal loading. In non earthquake regions where the wind forces are not severe, the masonry infilled concrete frame is one of the most common structural forms for high-rise construction. The frame is designed for gravity loading only and in the absence of an accepted design method the infills are presumed to contribute sufficiently to the lateral strength of the structure for it to withstand the horizontal loading. The simplicity of construction and the highly developed expertise in building that type or structures have made the infilled frame one or the most rapid and economical structural forms for tall buildings.

In countries with stringently applied Codes of Practice the absence of a well recognized method of design for infilled frames has severely restricted their use for bracing. It has been more usual in such countries when designing an infilled frame structure to arrange for the frame to carry the total vertical and horizontal loading and to include the infills on the assumption that, with precautions taken to
avoid load being transferred to them. the infills do not participate as part of the primary structure. It is evident from the frequently observed diagonal cracking of such infill walls that the approach is not always valid. The walls do sometimes attract significant bracing loads and in so doing modify the structure's mode or behavior and the forces in the frame. In such cases it would have been better to design the walls for the lateral loads and the frame to allow for its modified mode of behavior.

To brace a structure, the arrangement of infill walls within the three-dimensional frame must satisfy the same requirements as for the layout of bracing in a steel structure. Within any storey the infills must be statically capable of resisting horizontal shear in two orhogonal directions as well as resisting a horizontal torque. To achieve this there must be at least three infills that may not be all parallel or all concurrent. They must of course also be able to satisfy the strength and stiffness requirements.

Certain reservations arise in the use of infilled frames for bracing a structure. For example it is possible that as part of a renovation project partition walls are removed with the result that the structure becomes inadequately braced. Precautions against this either by including a generously excessive number of bracing walls or by somehow permanently identifying the vital bracing walls, should be considered as part of the design. A reservation against their use where earthquake resistance is a factor is that the walls might be shaken out of their frames transversely and consequently be of little use as bracing in their own planes. On the basis of substantial field evidence this fear is well justified. Their use in earthquake regions, therefore should be with the additional provision that the walls are reinforced and anchored into the surrounding frame with sufficient strength to withstand their own transverse inertial forces.

Panama Canal hits milestone - Final set of lock gates installed in April, 2015

7:32 PM Civil Engineering , Construction Management , Hydraulics , structures

An illustration explaining key facts about lock gates

By linking the Pacific and Atlantic oceans, the Panama Canal revolutionized global shipping when it opened nearly a century ago. However, the canal's capabilities are quickly being outpaced by the ever-growing ships that pass through it. In order to accommodate the next generation of over-sized vessels, the Panama Canal is receiving its most ambitious upgrade in 93 years - a third channel hemmed in by these gargantuan flood gates.

Panama Canal hits milestone - Final set of lock gates installed in April, 2015

View of a gate before installation

A major milestone was reached on the Panama Canal expansion project on April 28, as the eighth and fi nal lock gate was installed on the Pacifi c side of the route. Th ere are another eight lock gates already installed on the Atlantic side, for a total of 16. The final gate is one of the heaviest. It weighs 4,232 tonnes and measures 57.6 m wide by 10 m long by 33 m high. Manufactured in Italy, the new gates arrived in Panama in four staggered shipments starting in August 2013.

Panama Canal administrator Jorge L Quijano said, “Today’s installation is a key milestone in the expansion programme and another important step forward for the Canal,” The Panama Canal Authority (ACP) reports that expansion work is now 88% complete. It added that several major project components, including all excavation and dredging work have been completed.

In other news, ACP is to appeal against the December adjudication board ruling that it has to pay US$ 234 million to consortium Grupo Unidos por el Canal, (GUPC) and extend its contract by six months. The appeal will go before an arbitration hearing in Miami, US.

The dispute relates to poor quality basalt, which was to be used for aggregates on the project as well as a delay on ACP’s part in approving the concrete mix to be used on the project. GUPC said the rock was not of the same quality as indicated in the bidding documents issued by ACP.

Celebrations on installation of final set of lock gates

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Los Angeles Abrasion Resistance Test

1:06 PM Civil Engineering , Construction Management , Construction Materials

Abrasion is known as process of scraping or wearing something away, technically speaking; abrasion in geology is the mechanical scraping of a rock surface by friction between rocks and moving particles during their transport by wind, waves, gravity, running water or erosion. The intensity of this erosion effect depends on the hardness, concentration, velocity and mass of the moving particles.

What is abrasion, wear and tear?

Pavements in transportation engineering, either rigid or flexible have aggregates of specific sizes. These aggregates throughout their life are subjected abrasive effect of moving traffic vehicles. Whether it is sub-base, base or wearing course the aggregates are subjected to wear and tear. Aggregates transfer their loads from vehicles to ground through the interlock and toughness of their rigid surface.
The aggregates, thus, must be hard enough to resist crushing, degradation and disintegration from any associated activities. While fine aggregates are used among the coarser aggregates the load transferring mechanism is bit easy due to the cushioning effect of the fine aggregates, in case of gap or open graded Hot mix asphalt (HMA), where there are no such fines or some are missing, toughness of aggregates play a pivotal role in defining the life of a pavement.

Resistance to Abrasion?

Absence of abrasion resistance, hardness or toughness in aggregates would result in premature degradation, dust pollution early loss of skid resistance and many other problems as well.
Extent of Resistance to abrasion is measured in laboratory by a test called “Los Angeles Abrasion test” or L.A Test. Los Angeles abrasion test is an empirical test; meaning that it doesn’t have a numerical or analytical concept as its base. Though it relates and defines well with the toughness of the aggregates but generally do not show a good relationship with the field performance of the subject sample.

Background

Theory of Los Angeles abrasion test is to produce the abrasive action by use of standard steel balls which when mixed with aggregates and rotated in a drum for specific number of revolutions also causes impact on aggregates. The percentage wear of aggregates due to rubbing with steel balls is determined and is known as Los Angeles Abrasion value

Summary

Based on grading of aggregates select the number of steel balls and respective sieve sizes are arranged and total of 5000g sample is prepared. The sample is placed in a steel rotating drum along with the steel spheres or “charge”. As the drum rotates the drum picks up the aggregates and steel spheres and then drops them on the opposite end. This rotating, crushing and impact generates the abrasive effect. After specific number of revolutions, aggregates are removed from the drum and sieved on No. 12 (1.70 mm) sieve. The aggregate that is retained on the sieve is weighed and the difference between the weight is reported as percentage and given as Los Angeles Abrasion value.

Table 1 : Grading of Aggregates

Table 2: Grading with number of charge and weight of sample in grams

Procedure

1) The sample obtained is cleaned and dried in oven at 105 to 110 degree Celsius.
2) Select the grading of the aggregates such that it suits best with the grading to be used in construction as shown in the table;
3) Arrange the sieves as per grading and weight the material retained on specific sieves such that the total weight becomes 5000 g.
4) Select the charge or steel balls for the Los Angeles Abrasion test as per the grading.
5) Place the aggregates and the charge in to the steel drum.
6) Rotate the Los Angeles Abrasion testing machine at a speed of 30 to 33 revolutions per minute (rpm). The revolutions is also dependent on the grading of the aggregates, it is 500 for grading A, B, C and D while 1000 for E, F and g.
7) The machine after specific revolutions is stopped and material is discharged to a tray.
8) The material is then sieved from Sieve No. 12 or 1.70 mm.
9) The material that would retained on sieve No. 12 is weighed and noted.

Observations and calculations

Original test sample mass = M(original) = ____________ g
Final test sample mass = M(final)= ________________ g
Loss = ((Mo – Mf)/Mo) x 100
Los Angeles Abrasion value (L.A Value) = _______________ %

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Creative Construction Conference 2015

11:24 AM Conferences , Construction Management , Construction Materials

Dear Colleagues and Friends,

Creation is an inspiring endeavor. This is especially true when one creates objects of a size that only a few people can. Cathedrals or skyscrapers, bridges or aqueducts, highways or dams are not only fascinating due to their size but also because they greatly affect the lives of all people in their proximity – for decades or even centuries. Construction…this is a true creation.

The growing demands for a “better” built environment – even if the meaning of “better” is hard to define in this context – requires increasing levels of diverse knowledge. As time progresses, it is getting harder to live up to the ever growing expectations: trains begin to compete with the speed of airplanes, buildings may be expected to produce rather than consume energy, and in the not-so-distant future we will build in outer space, most likely with advanced robotics.

The Creative Construction Conference is organized to provide a forum for those ambitious researchers and practitioners from around the world who have realized that the construction industry is rapidly changing and accept that building materials, construction technologies, and project management will creatively and quickly evolve in the future.

You are cordially invited to participate in our fourth Creative Construction Conference in June, 2015. This year Krakow – the former capital city of Poland – will play the gracious host of the upcoming Conference.

Accepted papers will be published in the conference proceedings, extended versions of selected papers will be published in Scopus-indexed Procedia Engineering. Furthermore, a further few selected, expanded and fully refereed papers that fit the scope and mission of Automation in Construction will be published in a special section of the journal.

Over the past four years, the Creative Construction Conference has earned its reputation and has become the largest construction management conference in Europe. With your help we can go even further.

We look forward to exploring the known and unknown boundaries of construction together.

We hope to see you this June in Krakow.

More information and registration

Concrete Sector Debates European Union Rules

10:22 PM Civil Engineering , Construction Management , Construction Materials , News

Initiative launched by sector to examine key issues affecting sustainable construction.

A high level debate on sustainable construction featuring key stakeholders at EU level was held as the European concrete sector came together at the end of May to launch The Concrete Initiative. According to the initiative, construction is the largest single economic activity and the greatest industrial employer in Europe with some 20 million jobs.

Concrete Sector Debates European Union Rules

The concrete industry as a whole employs some 550,000 people in the EU, generating approximately €65,0oo added value per employed capita per annum. Bearing this in mind, the launch event for the Concrete Initiative focused on a debate with EU stakeholders on key issues including the regulatory framework which is required to achieve Europe’s goals, as well as the need for local resources, local manufacturing and a local market.

The initiative also called for EU legislation to remain material neutral. This followed the publication of a new European Commission Communication entitled A New EU Forest Strategy for Forests and the Forest-based Sector.

The concrete lnitiative called the communication misleading in the way it promotes the use of wood as a sustainable construction material. According to the initiative, the EU study shows a general call to favour wood over other building materials, without underpinning such a call by robust analysis that compares different building solutions over the whole life cycle of a building.

The Concrete lnitiative hopes to continue to engage with EU authorities on how to stimulate construction through policy measures and standards that generate growth and innovation in a more sustainable way. The concrete Initiative gathers together the cement and concrete sectors. It is composed of CEMBUREAU (the European Cement Association) BiBM (the European rederation of Precast Concrete) and ERMCO (the European Ready-Mixed Concrete Organization).

(July, 2014)

US $ 1 Billion-Plus Mega Construction Disputes Reported

10:04 PM Civil Engineering , Construction Management , News

Construction disputes were solved quickest in Europe, but the highest values were found in Asian markets.

The average value of disputes on major construction projects increased 1.2% last year to US$32.1 million (€23.54 million), according to consultant Arcadis, which added that last year saw the first ever US$1 billion (€733 million)-plus disputes in the industry. Arcadis said it was working on three “mega disputes including the Panama Canal expansion project. According to Global construction Disputes: Getting the Basics Right, the fourth annual report by Arcadis on this topic, dispute values were the highest in Asia last year at an average of Us$41.9 milllion (€30.72 million), closely followed by the Middle East at US$40.9 million (€29.99 million).

The disputed 'Panama Canal Expansion Project Site'

In the US, dispute values more than tripled compared to last year, to US$34.3 million (€25.16 million), and also rose in the Uk to their highest value since the report started at US$ 27.9 million (€20.46 million). The report also said disputes took, on average, less time to resolve in 2013 at 11.8 months, down from 12.8 months in 2o12. They took longest to resolve in the Middle East at 13.9 months, and the Us at 13.7 months. Disputes in continental Europe tended to be resolved the quickest at 6.5 months.

Mike Allen, global head of contract Solutions at Arcadis, said, Today's major construction programs are fast paced, complex and involve a multitude of supplier parties, so there are numerous points at which a dispute can occur. Many of these disputes are resolved out of the public eye but do often result in heavy costs and time overruns.

Our research indicates the scale of this problem and highlights the need for better contract administration, more robust documentation and a proactive approach to risk management to help mitigate against the most common causes of dispute.

The research found that the most common causes of construction disputes related to the administration of contracts. The top five causes in 2o13 were failure to administer the contract properly, failure to understand and/or comply with its contractual obligations, incomplete design information or employer requirements, failure to make interim awards on extensions of time and compensation, and poorly drafted or incomplete and unsubstantiated claims.

Party-to-party negotiation was deemed the most popular method of alternative dispute resolution in 2013, followed by arbitration and adjudication.

(July, 2014)

Renting Versus Purchasing Construction Equipment

9:34 PM Civil Engineering , Construction Management , Machinery , Mechanical Engineering , Quantity Survey

For the contractor who is new in the construction business, the decision whether to rent or purchase equipment is usually quite easy to make because, lacking surplus cash and without a well-established credit rating, the only viable alternative is renting.

For the older, more mature construction business, the decision may be a great deal more difficult. This contractor, who is more likely to be in a position in which funds and credit sources are available for equipment investments, has to determine if such investments are justified. Buying construction equipment is justified only where the investment promises net benefits in comparison with the alternative of renting equipment and investing the cash elsewhere.

A contractor does not necessarily have to own any construction equipment in order to carry on business. In most parts of the country there are many companies in the construction equipment rental business offering competitive rental rates on a large selection of equipment. There can be distinct advantages to renting equipment, including:

1. The contractor does not have to maintain a large inventory of specialized plant and equipment where individual items are used infrequently.
2. The contractor has continuous access to the newest and most efficient items of equipment available.
3. There is little or no need for equipment warehouse and storage facilities.
4. There is a reduced need for the contractor to employ maintenance staff and operate facilities for their use.
5. Accounting for equipment costs can be simpler when equipment is rented.
6. There may be significant savings on company insurance premiums when a contractor is not maintaining a inventory of plant and equipment.

However, when the construction operations of a contractor generate a steady demand for the use of certain items of equipment or plant, there can be distinct financial benefits gained by owning equipment. There can also be a marketing advantage to the contractors who own their own equipment due to the perception that these contractors are more financially stable and committed than others who own no equipment. In fact, some owners require contractors who bid on their projects to list on the bid the company-owned equipment they propose to use in the work. This information is utilized in the owner’s assessment of the bidder.

Where a comparison of equipment ownership with the rental alternative strictly on the basis of cost is needed, the full cost per unit of time of owning an item of equipment has to be determined. To estimate the full ownership cost, the following aspects of equipment ownership have to be considered:

1. Depreciation expense
2. Maintenance and repair costs
3. Financing expenses
4. Taxes
5. Insurance costs
6. Storage costs
7. Fuel and lubrication costs

Depreciation

In everyday usage the term “depreciation” refers to the decline in market value of an asset. To accountants the term has a more narrow meaning having to do with allocating the acquisition cost of an item of plant over the useful life of that asset. The way this allocation of cost is calculated may or may not reflect the loss of market value; more often than not it does not. Also, the allocation of depreciation costs considered here is not related in any way to tax considerations. For tax purposes a completely different depreciation schedule may be adopted.

The process of allocating the cost of the item over its useful life is known as “amortization,” and there are several depreciation methods available to calculate amortization of an asset. Here we will consider three methods:
1. The straight-line method
2. The declining-balance method
3. The production or use method

Maintenance and Repair Costs

The costs of maintenance and repairs of plant and equipment comprise a factor that cannot be ignored when considering ownership costs. Equipment owners will agree that good maintenance, including periodic wear measurement, timely attention to recommended service, and daily cleaning when conditions warrant it, can extend the life of equipment and actually reduce the operating costs by minimizing the effects of adverse conditions. All items of plant and equipment used by a construction contractor will require maintenance and probably also some repairs during the course of their useful life. The contractor who owns equipment usually sets up facilities with workers qualified to perform the necessary maintenance operations on equipment. It is the cost of operating this setup that we have to consider and include in the total ownership charges applied to items of plant and equipment.

Construction operations can subject equipment to considerable wear and tear, but the amount of wear varies enormously between different items of equipment used and between different job conditions. The rates used in the following examples are based on the average costs of maintenance and repair, but since these costs can vary so much, the contractor formulating equipment operating prices should adjust the rates for maintenance and repairs according to the conditions the equipment is to work under. Again, as in many places in estimating, good records of previous costs in this area will much improve the quality of the estimator’s assessment of probable maintenance costs.

Maintenance and repair costs are calculated as a percentage of the annual depreciation costs for each item of equipment. When depreciation is calculated using the straight-line method, as in the examples 6 and 7 that follow, the result is a constant amount being charged yearly for depreciation and then a second constant amount is allowed for maintenance and repairs. Realistically, depreciation will be high in the early years of ownership, while actual maintenance and repair costs in these years should be low. The relative values of yearly depreciation and maintenance costs will gradually reverse until, in the later years, low depreciation will be accompanied by high maintenance and repair bills. Using a constant amount yearly for these two expenses, therefore, would seem reasonable as the variance of one factor is offset by the countervariance of the other factor.

Financing Expenses

Whether the owner of construction equipment purchases the equipment using cash or whether the purchase is financed by a loan from a lending institution, there is going to be an interest expense involved. The interest expense is the cost of using capital; where cash is used, it is the amount that would have been earned had the money been invested elsewhere, that is, the forgone interest revenue. Where the purchase is financed by a loan, the interest expense is the interest charged on the loan. In both cases the interest expense can be calculated by applying an interest rate to the owner’s average annual investment in the unit. The average annual investment is approximately midway between the total initial cost of the unit and its salvage value.
Thus:
average annual Investment = (Total Initial Cost + Salvage Value)/2

The interest rate used to calculate the financing expense will vary from time to time, from place to place and also from one company to another depending mostly on its credit rating and how good a deal it can get from the lending institution. In the examples that follow, we will use a rate of 6%.

Taxes, Insurance, and Storage Costs

Just as with investment expenses, significant variations can be expected in the cost of the annual taxes, insurance premiums, and storage costs together with fees for licenses required and other fees expended on an item of equipment. Where these expenses are known, they should be added into the calculation of the annual ownership costs of the equipment. In the case where information on these costs is not available, they may be calculated as a percentage of the average annual investment cost of the piece of equipment. The interest expense rate and the rate for taxes, insurance, and storage costs are often combined to give a total equipment overhead rate. Below we will use an equipment overhead rate of 11%, which comprises 6% for the investment rate and 5% to cover taxes, insurance, and storage costs.

Fuel and Lubrication Costs

Fuel consumption and the consumption of lubrication oil can be closely monitored in the field. Data from these field observations will enable the estimator to quite accurately predict future rates of consumption under similar working conditions. However, if there is no access to this information, consumption can be predicted where the size and type of engine are known and the likely engine operating factor is estimated. This operating factor is an assessment of the load under which the engine is operating. An engine continually producing full-rated horsepower is operating at a factor of 100%. Construction equipment never operates at this level for extended periods, so the operating factor used in calculating overall fuel consumption is always a value less than 100%. The operating factor is yet another variable with a wide range of possible values responding to the many different conditions that might be encountered when the equipment under consideration is used. In the examples that follow, the specific operating factors used can be no more than averages reflecting normal work conditions. Again, there is no good substitute for hard data carefully obtained in the observation of actual operations in progress.

When operating under normal conditions, namely, at a barometric pressure of 29.9 in. of mercury and at a temperature of 60ºF, a gasoline engine will consume approximately 0.06 gallons of fuel for each horsepower-hour developed. A diesel engine is slightly more efficient at 0.04 gal. of fuel for each horsepower-hour developed.

Equipment Operator Costs

Whether a contractor decides to rent or own the equipment used on its projects, the cost of operating the equipment has to be considered. In some situations rentals may be available that include an operating engineer as part of the rental agreement. This variety of rental agreement is sometimes available for excavation equipment, and it can be a preferred alternative when the rental company offers a high-caliber equipment operator who is familiar with the particular excavation unit and is capable of high productivity.

More often than not, however, equipment is rented without an operator. So, just as in the case in which the contractor is using company-owned equipment, the labor costs for operating the equipment have to be calculated and added to the estimate. The usual way to price these costs is to apply an operating engineer’s hourly wage alongside the equipment hourly rate and then use the expected productivity of the equipment to determine a price per measured unit for labor and a price per measured unit for equipment. Example 5 illustrates this method of pricing equipment and operator’s costs. Note that the unit prices for labor and for equipment should always be considered separately as the labor prices have to be included in the total labor content of the estimate so that “add-ons” can be applied to this amount at the close of the bid.

Example:

Where the hourly cost of an excavator is $172.00, the wage of an operator for this equipment is $40.00 per hour, and the expected productivity of the excavator is 50 cu. yd. per hour, the unit prices for labor and equipment would be calculated thus:
Labor
$40.00/50 cu. yd.
= $ 0.80 per cu. yd.

Equipment

$172.00/50 cu. yd.

= $ 3.44 per cu. yd.
These unit prices can now be applied to the total quantity of excavation that this equipment is expected to perform in accordance with the takeoff.

Company Overhead Costs

Where the equipment ownership costs calculated in accordance with this chapter are to be used as a basis of rental rates charged by the contractor to others for the use of the contractor’s equipment, the full rental rates should include an amount for company overhead costs and amount for profit. Company overhead costs are basically the fixed costs associated with running a business. They may include the cost of maintaining a furnished office, office equipment, and personnel together with all the other costs of business operation. Since the rental rate quoted by a contractor to another party for the use of the contractor’s equipment is, in a sense, a kind of bid, the same considerations should be applied to the markup on the rental rate as are applied to markup on any of a contractor’s bids.

Project Report: Japanese New Iconic National Stadium, Tokyo

9:21 PM Civil Engineering , Construction Management , News , Reports

The new National Stadium in Japan is a landmark project with a challenging timescale and a nailed on deadline.

Japan’s existing National Stadium

Japan’s existing National Stadium sits in a large sports park in Tokyo's Shinjuku ward, a busy suburb of the capital city. The existing venue was opened in 1958 for that year’s Asian Games, and went on to be the centerpiece of the 1964 Summer Olympic Games.

At the time it was a world-class stadium, but sporting venues have come a long way in the intervening 50 years. Today the National Stadium’s shallow bowl, open-top design and relatively low capacity of just over 54,000 people, only 48,000 of which are seated, make it something of an out-dated facility. Recognizing this, the facility’s owner, quasi-governmental organization Japan Sport Council (JSC), has been looking at some time to refurbish or replace the stadium. This was given a certain impetus by the decision in July 2009 by the International Rugby Board (IRB) to name Japan as the host of the 2019 Rugby World Cup.

According to Yoshitaka Takasaki, JSC’s divisional manager for its general affairs department, and the man responsible for the administrative aspects of planning and constructing the new Narional Stadium. the decision to build a new facility was taken in early 2012. At the time, this was purely in light of the 2019 Rugby World Cup, but the project received another boost in September 2013, when Tokyo won the competition to host the 2020 Summer Olympic Games.

Planned Iconic New National Stadium, Tokyo, Japan

There can be little doubt about JSC’s ambitions for the quality of the venue it wants to build. As the organization's president, Ichiro Kono said, "As a national project conducted once every half century, we aim to build a stadium that will be recognized as a global model.” Mr Takasaki said the plan was to build a venue that would be suitable for a range of events — not just sports like rugby, athletics and football, but concerts as well. A closeable roof was another requirement to allow the stadium to be used in all weathers and in terms of capacity, the International Olympic Committee (IOC) requires the main athletics stadiums to seat 80,000 people, so that was a critical requirement too.

One of the problems with combined athletics and ball sports stadiums is that the presence of a running track can leave spectators too far from the action when it comes to a rugby or football match. To get around this problem, JSC envisages a design where a moveable lower tier of seats can be pushed out over the track to put fans much closer to the pitch.

This stadium could be the key venue for any world-class sporting event said Mr Takasaki.

Between the decision to build a new stadium and the announcement of Tokyo's successful bid for the 2020 Olympics, JSC launched an architectural competition to design the new venue. As with every aspect of this project, this was done on a tight timescale, with the July 2012 competition launch carrying a deadline of November 25 that year.

Despite the challenging timetable, there was no shortage of architects entering with their visions for what would clearly be a high-profile and iconic project. The winner was UK-based Zaha Hadid Architects. No doubt spurred by the news of Tokyo’s winning bid for the 2020 Olympics in September 2012. The other cities in contention up to that point had been Madrid, Spain and Istanbul, Turkey.

Stadium Design

If Beijing had the Bird's Nest stadium for the 2008 games, Tokyo's centerpiece venue stands a good chance of being nick named ‘The Cycling Helmet.’ The design features series of shallow arches rising from outside the bowl of the stadium, with translucent materials filling the voids between them to create the fixed and open-able sections of the roof. According to Mr Takasaki, the design is currently being finalised ahead of the start of work on site later this year. The first element of the project will be the demolition of the existing national stadium and the contract for this, valued at around JPY 6.7 billion (US$ 65 million) was due to be put out to tender.

Planned Iconic New National Stadium, Tokyo, Japan

The existing stadium is a substantial structure that escaped the 2011 earthquake unscathed, so its demolition looks set to be a significant project in its own right. It is a five storey structure built predominately from reinforced concrete. The total area of the stadium, including track and in-field is 71,707 sq.m, with the stadium structure itself having a 33,716 sq.m footprint.

Mr Takasaki said the demolition portion of the project was scheduled for 16 months, with a start date in July this year. That work would carry on until October 2015, with the 42-month construction phase due to follow-on immediately.

With the start of the construction portion of the scheme still well over a year away, JSC is working to finalize the designs. Mr Takasaki said the main consideration was to decide between the design as originally published or a minimized version which would be cheaper and quicker to build, but which would leave out some elements.

If everything runs to schedule, the planned timescale would see the stadium completed in February 2019, some six to seven months ahead of the Rugby World Cup kick-off on September 6 thar year. The opening of the 2020 Summer Olympics is due to take place on July 24 the following year, some 17 months after completion of the project.

According to JSC, the total budget for the project is JPY 169.2 billion (US$ 1.64 billion). The bulk of this some JPY 138.8 billion (US$ 1.3 billion) is of course for the construction of the new stadium. The remaining JPY 30.4 billion (US$ 295 million) breaks down inro the JPY 6.7 billion (US$ 65 million) for the demolition work and JPY 23.7 billion (US$ 230 million) for various environmental and development work associated with the project.

Funding will come from a combination of national Government funds, Tokyo’s City budget and a contribution from Toto, the Japanese national sports lottery. Mr Takasaki said the size of the individual contributions were yet to be decided but added that the project was effectively underwritten by the national government. One of the biggest problems associated with the project is, according to Mr Takasaki the planning and flow of materials. Tokyo is a famously large dense and sprawling city and the logistical considerations are not helped by the fact that plans need to be coordinated with the city government as well as the three suburban wards that border on the stadium site. It all makes for a formidable challenge, but as Mr Takasaki said,

So far. so good.

Steps in Construction of Reinforced Concrete Structures

4:09 AM Civil Engineering , Concrete , Construction Management , structures

Once the design has been completed, a team of experienced and knowledgeable construction workers and supervisors is required to transform the structural design into the finished construction. Concrete construction is a complex process that involves several activities, from hatching and mixing the ingredients to pouring fresh concrete into forms and curing the new construction. There are several factors that might influence the quality of the final product in this process, that is, the built structure. The critical activities associated with the construction of cast-in-place reinforced concrete structures are described below.

Development of Structural Drawings

Structural design should be based on the sound application of fundamental principles of reinforced concrete design and a knowledgeable use of building codes and standards. However, structural design is ineffective if it is not possible to ensure its proper implementation. The structural engineer has a critical role in communicating the design information to personnel involved in the construction process. In the world of structural engineering, structural drawings and specifications are a critical means of communication between the structural engineer and the contractor. Consequently, the importance of an accurate set of structural drawings that communicate clear and concise information cannot be underestimated.

In reality, even a well-designed structure may result in a variety of problems, both financial and legal, when structural drawings do not properly communicate the design intent. A poor set of structural drawings may expose the engineer to various problems, such as extra costs, delays in the construction schedule, disputes in the field, construction errors, unhappy contractor/owner, and even legal disputes.

Construction Estimating and Tendering

Once the structural drawings have been completed, the contractor produces an estimate of the concrete and reinforcing steel quantities, as well as the amount of formwork and shoring. This estimate is based on structural drawings and specifications that are issued for construction. Based on these drawings, the estimator should be able to estimate the quantity of materials and also the extent of complexity in the construction procedures, any unusual complications associated with the erection, formwork, and shoring, etc. The drawings must be clear and concise and without ambiguities. When drawings are ambiguous, there could be large variations in price between competitive bids submitted by different contractors in the bidding process. In general, a variation in the bid price of over 10% is considerable, as it leaves the owner confused about the proper market price for the project. This is an unfavourable situation for the owner, who ultimately pays for the construction. On the one hand, the owner may feel that (s)he is overpaying if the highest bid is accepted. On the other hand, a bid below fair market value may lead to problems during construction, usually in the form of numerous requirements for extra payments by the contractor in trying to recover losses caused by the low bid.

Detailing of Reinforcement

The reinforcing contractor interprets the information on structural drawings and produces reinforcing steel detail sheets. These sheets are primarily used by the shop to cut and bend the reinforcing bars required for the project. Each bar has a unique code that is referred to by the person responsible for rebar placement in the field.

Placing of Reinforcement

Once the reinforcement has been detailed and cut in the shop, it is delivered to the site in bundles. In some cases, rebars are cut and bent at the construction site. Placement of the reinforcing steel is carried out by rebar placers. Their role is to interpret structural drawings along with the detail sheets and then place the reinforcing steel as precisely as possible. Rebar clearances must be properly shown on the structural drawings in order for the rebar placer to accurately place bar supports to ensure proper bar position.

Supplying the Concrete

The concrete ready-mix company will supply concrete based on the concrete strengths specified on the structural drawings and the mix designs that meet the specific climate and workability requirements of the site. Special concrete placement procedures, such as placement by pumps or wheelbarrows; site batching; or cylinder testing by an independent testing agency, must be carried out in accordance with the structural drawings and specifications.

Installation of Concrete Formwork and Shoring

Formwork and shoring support the weight of the wet concrete and other construction loads. Form work is a temporary structure made of wood, metal, or plastic, and it is constructed to form the final shape of a concrete member. The concrete formwork contractor must hire an engineer who is responsible for designing and producing drawings showing the formwork and shoring supports for concrete beams, slabs, walls, columns, and foundations. The formwork must be built precisely in accordance with the structural drawings and must allow for the proper placement of reinforcing steel and wet concrete without any major deviations in shape and stability.

Placing and Curing the Concrete

The proper amount of concrete must be placed such that the slab thickness, beam sizes, and wall and column dimensions are in accordance with the structural drawings. In some cases, special procedures and construction sequences are required to minimize the development of cracks in the concrete due to structural or architectural restraints or temperature changes. For example, pour strips are often used in large floor structures to separate different floor sections to be placed in the same pour. In some cases, a continuous gap of minimum 300 mm width is left between two adjacent floor sections. A delay period (usually 28 days) is specified to allow for shrinkage to take place between these pours. Subsequently, pour strips between floor sections are filled with concrete. In some cases, allowance for various types of joints (such as control joints and expansion joints) needs to be made during construction.

The curing process is critical for fresh concrete to gain the required design strength. Improperly cured concrete tends to exhibit extensive cracking and creep-induced deflections. Structural drawings need to specify the curing procedures in accordance with the design requirements. It is commonly required to provide curing for fresh concrete over a 28-day period.

Reshoring and Special Construction Procedures

Reshoring and Special Construction Procedures

By and large, construction projects require an accelerated concrete placement schedule. In some cases, concrete formwork may need to be stripped (removed) as quickly as 3 days after the placement. Green concrete (concrete that has not attained design strength) must develop sufficient strength to support its self-weight plus the construction load. However, concrete stripped shortly after casting may develop larger creep deflections than concrete stripped after proper curing. Hence, a proper re shoring sequence must be specified by the engineer responsible for construction to prevent sustained loads from being prematurely applied to green concrete.

Procedures that are relevant to the overall design objective need to be outlined on the structural drawings. Such special procedures are generally related to the mitigation of the effects of shrinkage and cracking, as well as creep and long-term deflections. These procedures usually bear certain cost implications and must be clearly communicated on the structural drawings before construction starts. When the structural engineer requests a special procedure after construction has begun that was not specified on the drawings, there is a chance that the contractor will charge extra to carry it out.

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