Thursday, December 16, 2010

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 



Monday, December 13, 2010

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



Tuesday, November 30, 2010

The contract documents



The contract documents in order of importance are follows


Form of contract
This is the principal document and will often be a printed standard form, such as one of the variants of the JCT Form.
The Articles of Agreement
The Conditions
Total contract sum

Condition of contracts
The condition of contract is represent the legally binding agreement between the parties and cover such important as expected completion date of the work, methods and timing of payments, access to the works etc.

Specification
The specification may describe the method of working and quality required in the works, to assist the contractor in preparing the tender. Specification is used during.
Tendering, to help the estimator to price the work that is required to be carried out
Construction by the designer in order to determine the requirements of the contract, legally technically and financially, and by the building contractor to determine the work to be carried out on site.

Bill of Quantities
When tendering, the bill of quantities is sent out as part of the package of contract documents for the contractor to price. The  enters a unit price or rate against each item of work, the quantities are then multiplied by the rate and the price for the item of work established all the item prices are then added up to give the contract price. Provision may be made for variation and additional work within the bill of quantities by including provisional sums.

Contract drawings
The drawings should be indicate the location, scope and design complexity of the works and show graphically the full extent of what is required to be constructed.


What Is Construction Economics?



“Construction Economics is the construction Project to study of how individuals and groups make decisions with limited resources as to best satisfy client’s wants, needs, and desires".  Resources available to the construction industry may be appropriately allocated and optimally used to products and services.

Evaluation of the total (life cycle) costs of alternative solutions to the problem of meeting the requirements of a particular client and choice of the best solution.

Assessment of the determinants of demand for construction activity and study of the effect on the industry of different volumes and mixes of total demand.

Consideration of the nature of the construction industry and its needs, strengths and weakness.



Friday, November 26, 2010

Shovel loader


These are used primarily to excavate earth and load into hauling units such as trucks or tractor pulled wagons or in conveyer belt etc. Shovels can be used to excavate all type of soils except hard rocks without prior loosening.

The quantity of materials that can be hauled by the loader depends upon its bucket capacity. Loader bucket capacities are specified by the manufacturer either in terms of heaped capacity or struck capacity. However, planning can be based on the loose soil struck capacity of the bucket, and the heaped capacity (loose soil) can be converted into struck capacity (loose soil) as under:
Bucket struck capacity = bucket heaped capacity X fill-factor

Type of shovels  
Shovels can be divided into the following groups:
1. Crawler mounted shovels
2. Tyred mounted shovels
3. Self-propelled shovels
4. Non self-propelled shovels.


batteries Shovel loader