A P Møller School Schleswig - Award News

C. F. Møller Wins RIBA European Union Award and Worldwide Brick Award

The A. P. Møller School designed by C.F. Møller Architects has won both the prestigious 2010 RIBA European Union Award and the 2010 Worldwide Brick Award. The school is located on a scenic site in Schleswig in Germany. The site's interaction with the town of Schleswig and the picturesque landscape of Schlei Fjord was a primary generator of the design.

Types of construction contracts

Types of construction contracts/The Nature of Construction Contracts

A contract is an understanding made between two or more persons, by which rights are acquired on the one side to acts or forbearances on the other. To make an agreement which results in a contract, there must be an offer and acceptance which leads to a binding force of obligation.

Lump sum contract

A lump sum contract is an agreement pursuant to which one party consents to pay another party a set dollar amount for completing the work or providing the goods described in the agreement. Typically, lump sum contracts do not require contractors to provide a detailed breakdown of costs. Rather, the payment of the total contract price is linked to the contractor completing all of the work specified in the contract.

Cost-Plus

Under this arrangement the contractor is reimbursed for the actual cost of labor and materials, plus charges a fee (typically an agreed-upon lump or percentage of the total costs) for overhead and profit.  This arrangement seldom begins with a blank slate regarding specifications and costs. Rather, the consumer and contractor will create a list of specifications and an estimated budget to match to those specifications.  Although the contractor under this arrangement will have to keep copious records of its costs, most residential consumers in a cost-plus arrangement suffer from kid-in-a-candy storeitis and overspend. One way to prevent breaking the budget is to set a guaranteed maximum price.  However, even a maximum price will not alleviate problems.

Unit Price Contract

In a unit price contract, the risk of inaccurate estimation of uncertain quantities for some key tasks has been removed from the contractor. However, some contractors may submit an “unbalanced bid” when it discovers large discrepancies between its estimates and the owner’s estimates of these quantities. Depending on the confidence of the contractor on its own estimates and its propensity on risk, a contractor can slightly raise the unit prices on the underestimated tasks while lowering the unit prices on other tasks. If the contractor is correct in its assessment, it can increase its profit substantially since the payment is made on the actual quantities of tasks; and if the reverse is true, it can lose on this basis. Furthermore, the owner may disqualify a contractor if the bid appears to be heavily unbalanced. To the extent that an underestimate or overestimate is caused by changes in the quantities of work, neither error will effect the contractor’s profit beyond the markup in the unit prices.

Target Estimate Contract

This is another form of contract which specifies a penalty or reward to a contractor, depending on whether the actual cost is greater than or less than the contractor’s estimated direct job cost. Usually, the percentages of savings or overrun to be shared by the owner and the contractor are predetermined and the project duration is specified in the contract. Bonuses or penalties may be stipulated for different project completion dates.

Guaranteed Maximum Cost Contract

When the project scope is well defined, an owner may choose to ask the contractor to take all the risks, both in terms of actual project cost and project time. Any work change orders from the owner must be extremely minor if at all, since performance specifications are provided to the owner at the outset of construction. The owner and the contractor agree to a project cost guaranteed by the contractor as maximum. There may be or may not be additional provisions to share any savings if any in the contract. This type of contract is particularly suitable for turnkey operation.

Advantages of Suspension Bridges

Suspension bridges are adopted in places where it is difficult to construct other type of bridges. For very large spans, they can be adopted economically.

·         In a suspension bridge, tensile stresses are predominant. Thus it requires high tensile ropes, which are economical than mild steel trusses etc.

·         During construction, temporary central supports do not need to be built, and access to the construction is not required from beneath. This means busy roadways and waterways do not need to be disrupted.

·         The stresses are directly passed to the supports through cables and suspenders, hence slender sections are required effecting overall economy.

·         The area spanned by a suspension bridge is very long in proportion to the amount of materials required to construct bridges.

·         They are light and require no false work.

·         The material of construction can be transported easily.

·         The time of construction is less.

·         They provide the roadway at a low elevation and have low centre of wind pressure.

·         They give good aesthetic appearance.

·         They require no centering for construction.

·         There is no likely hood of failure during erection and after construction.

·         It is the safest structure as cables have vast reserve strength.

·         The chords of the stiffening truss can be repaired without interruption to traffic, while in other bridges the failure of a single truss member causes collapse of the bridge.

  What are the advantages/disadvantages of beam,arch, and suspension bridges?

Construction Ecology Nature as a basis for green buildings free download

Industrial ecology provides a sound means of systemizing the various ideas which come under the banner of sustainable construction. As designers of built environments focus increasingly on green and sustainable construction they will be able to learn much from the field of industrial ecology.
Construction Ecology Nature as a basis for green buildings free download 






LIST OF CONTENT


1 Defining an ecology of construction 7
2 Material circulation, energy hierarchy, and building construction 37
3 On complexity theory, exergy, and industrial ecology 72
4 Applying the principles of ecological emergence to building design and construction 108
5 Using ecological dynamics to move toward an adaptive architecture 127
6 Minimizing waste emissions from the built environment 159
7 Industrial ecology and the built environment 177
8 Construction ecology and metabolism 196
9 Construction ecology 220
10 Ecologic analogues and architecture 231
11 Natural metabolism as the basis for “intelligent” architecture 248
12 Green architecture 269


Construction Ecology Nature as a basis for green buildings free download 

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Methods of reducing corrosion for structural Reinforcement

Better grade of concrete with lower w/c ratio and well compacted.

A polymeric coating is applied to the concrete member to keep out aggressive agents. A polymeric coating is applied to the reinforcing bars to protect them from moisture and aggressive agents.

Fly Ash -  Using a Fly Ash concrete with very low permeability, which will delay the arrival of carbonation and chlorides at the level of the steel reinforcement. Fly Ash is a finely divided silica rich powder that, in itself, gives no benefit when added to a concrete mixture, unless it can react with the calcium hydroxide formed in the first few days of hydration. Together they form a calcium silica hydrate (CSH) compound that over time effectively reduces concrete diffusivity to oxygen, carbon dioxide, water and chloride ions. 

Modified quality of steel reinforcement which are less susceptible to corrosion such as special grade of stainless steel, CRS (Corrosion Resistant Steel),TMT steel etc.

Pre-applied impermeable coating (Epoxy, CECRI & CBRI coating)

Stainless steel or cladded stainless steel is used in lieu of conventional black bars

Admixtures (Nitrites and Nitrates) for concreting, which are to be added in the green concrete.

Electrochemical injection of the organic base corrosion inhibitors, ethanolamine and guanidine, into carbonated concrete.

Other inorganic inhibitors, which are known to be migratory in nature. The migration process is diffusion through water and diffusion through vapour phase.

Structural design aspects of corrosion control involve factors such as configurational (geometrical) considerations that minimize or, if possible, eliminate exposure to corrosives