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.

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

Preparation of a Cost Analysis

         

Preparation of a cost analysis

The primary purpose for using cost analysis of construction project provides useful source of cost information.  Any form of cost analysis should be provided in standard way with the following.

Information on the total project

Summary of element costs with preliminaries shown separately and also apportioned among the elements

A brief specification in element form

Sketch plans and elevations for the project

The amplified analysis

Information of the total project is important as it includes the building type which is necessary for future analytical purpose of a similar type of project. In addition, the client, location, tender date, contract particulars, market conditions, competitive tender list, project details, and brief cost information are provided under project information section of the cost analysis.

The following  basic principles  need to be followed in preparing the cost analysis

The qualitative aspects of the project should be expressed by reference to accompanying specification notes

An element should be of cost significance

The analysis should consider the features in different building which have heavy bearing on cost.

An element should be easily definable and capable of having the appropriate costs allocated against it with a minimum of effort on the part user

Other information relevant to the costs in the analysis should be provided as a background to these data

Construction of Cofferdams

 Cofferdam is a temporary structure built for the purpose of excluding or soil sufficiently to permit construction to proceed without excessive pumping, and to support the surrounding ground.

Construction of foundation is most important in a structure, so all the correct and safe actions should be taken while doing a foundation.

Cofferdam is commonly used for oil rig construction and repair, bridge and dam work, the cofferdam is usually a welded steel structure that is temporary and is typically dismantled after work is completed.

Cofferdams is used to provide a safe working space at foundation level

It’s difficult to handle deep foundations under water or ground in deep

Safety in construction of cofferdams

Construction of cofferdam presents safety problems unique to this type of construction.

They will be limited access, limited work areas, damp or wet footing, and deep excavations.

Provisions must be made for safe access in terms of adequate walkways, rails, ladders, or stairs into and out the lower levels.

The work may be within a waterway, in which case additional safety regulations may apply. These would include provisions for flotation devices, boats, warning singles, and suitable means for a rapid exit.

 

    Inside the Barge Gate Cofferdam

Inspection and Maintenance

Dams should be inspected regularly and immediately repaired if required.  A through inspection should be conducted following flood events.

Water removed from work area may be silty and should be discharged to a

vegetated area at least 30 m from the watercourse, or pumped through a filter bag

The weather forecast should be monitored to anticipate the occurrence of high flow

events.  Work operations should be adjusted to accumulate possible overtopping of

the coffer dams

       Barge Gate Cofferdam

Consideration of Selection of a cofferdam

Soil conditions

Location of the coffer dam (land/water)

Plan size of working area

Maximum depth of soil or water to be retained.

Nature of the permanent or floating structure

Effects on excising adjacent structures

Ground water level & their fluctuation

Construction time

Availability of equipment and material

Possible construction method & dismantling

Effects of noise, vibration and fumes, & fire risk.

It water cofferdam behavior of water.

Cofferdams is mainly of two types

Gravity coffer dam :-

Sheeting cofferdam