1. Specification
-describes in words, the work to be built, quality of material, workmanship and testing requirement.
-must be defined and precise.
-3 categories:
a. material specification-required types,quality and testing
b. workmanship-quality and safety requirements
c. performance-required performance
-may include standard and particular specification.
2. Daywork Schedule
-the engineer may if in his opinion it is necessary/desirable order in writing that any additional/substitution work shall be executed on a daywork basis.
-the contractor payment for this work will base on the condition set out in the daywork schedule included in BOQ.
3. Provisional Sum
-a sum of money fixed by engineer included in BOQ which is only to be expended, either in whole,in part or not in all under engineers direction for execution of work or the supply of goods, materials, services, or for contingency.
4. Prime Cost
- a sum of money included in BOQ which will be used for execution of work,supply of good,services for the work.
5. Bonds
-contractor often required to obtain a security bond
-find banks or insurance company willing guarantee to meet any damage up to certain amount sustained by the employer as the results of failure and defaults of contractor.
-cost of bond vary with the reputation of the contractor and the risk associated with the work.
6. Variation Order
-variations include additions,omissions,substitutions,alterations.
-change in quality,position,level,dimension
-variation to any part of work will be ordered by the engineer if it is necessary for completion or functionary of the works.
-variation orders must be confirm in writing form although may given orally to the contractor.
7. BOQ
-give the anticipated quantity for each operation of construction as calculated from the drawing.
-easier for comparison of tender prices
-easier for evaluation of finish work in each stage.
-convenient for changes order and evaluation.
-measurement type wherein the contract price is accumulated in a BOQ.
-list the constituent items of work,each of which is priced up by individually by a tendering contractor.
-quantities of work are stated to be the best estimate prior to tender
-work items remeasured during the contract and valued at the rates tendered by the successful contractor.
The Plant Organization
There are broadly two organizational method by which a contractor controls the purchase,maintenance, and use of mechanical equipment for construction work.
A) Central pool of plant
Advantage:
1. central maintenance facilities can be established. Experts can be employed and sophisticated machine tool for repair work can be purchased because of high utilization of their service can be foreseen.
2. It can be made self-accounting and its operation, carefully controlled from all financial aspects.
3. Specialized plant can be bought and its low utilization offset against the more profitable type of plant in popular demand.
4. Contract of all sizes can readily be served.
5. Reserves of plant are available for use at short notice.
6. Research and development of new equipment is possible.
Disadvantage
1. High cost involved in transport the plant from depot to various contract site.
2. Conflict occur where the profitability of the plant pool is first consider before the optimum operation and profitability of the contract.
3. There is no incentives for site to use the machines strictly accordance with their design. Plant may be inadequately serviced because it is not directly under the eyes of the central plant depot.
B) Individual large contract
Advantage
1. No need for central plant depot. Money can spend on other operation of the company.
2. Plant can be selected for each contract on the basis of the individual requirements of those contracts.
3. Maintenance will be rigorously carried out due to probably to sell the equipment and recoup some of its initial investment. As each contract is responsible for the maintenance of its own mechanical equipment.
4. Reduction in plants transport and haulage costs between a site and the central depot.
Disadvantage
1. Certain economics of large purchasing are lost as it is not readily possible to look at the purchasing of plant on a company-wide basis.
2. Lack of reserve plant to call on in an emergency.
3. Maintenance and repair work may be hampered due to lack of facilities. It is seldom economically viable to set up a comprehensive maintenance and repair depot at each and every site.
A) Central pool of plant
Advantage:
1. central maintenance facilities can be established. Experts can be employed and sophisticated machine tool for repair work can be purchased because of high utilization of their service can be foreseen.
2. It can be made self-accounting and its operation, carefully controlled from all financial aspects.
3. Specialized plant can be bought and its low utilization offset against the more profitable type of plant in popular demand.
4. Contract of all sizes can readily be served.
5. Reserves of plant are available for use at short notice.
6. Research and development of new equipment is possible.
Disadvantage
1. High cost involved in transport the plant from depot to various contract site.
2. Conflict occur where the profitability of the plant pool is first consider before the optimum operation and profitability of the contract.
3. There is no incentives for site to use the machines strictly accordance with their design. Plant may be inadequately serviced because it is not directly under the eyes of the central plant depot.
B) Individual large contract
Advantage
1. No need for central plant depot. Money can spend on other operation of the company.
2. Plant can be selected for each contract on the basis of the individual requirements of those contracts.
3. Maintenance will be rigorously carried out due to probably to sell the equipment and recoup some of its initial investment. As each contract is responsible for the maintenance of its own mechanical equipment.
4. Reduction in plants transport and haulage costs between a site and the central depot.
Disadvantage
1. Certain economics of large purchasing are lost as it is not readily possible to look at the purchasing of plant on a company-wide basis.
2. Lack of reserve plant to call on in an emergency.
3. Maintenance and repair work may be hampered due to lack of facilities. It is seldom economically viable to set up a comprehensive maintenance and repair depot at each and every site.
The Organization of Projects and Contracts
1.1 Project and Contract
The promoter of a capital project invests money in the realization of that project in order to either provide a service or to product goods. The project is conceived and developed to meet a predicted demand of the service or goods.
Return obtained:
-benefit to the users.(hospital,motorway)
-profit to the investors
-provide statutory service and make a small profit.(power station)
The promoter will employ specialists to design and manage the development of the project.
Architects,land agents, and engineers are but three of the disciplines involved.
The promoter may also enter into a legal agreement or contract with a contractor, or a number of contract, for the construction of the project.
The promoter may also, therefore, be called the client or employer.
He is concerned with the flow of money to and from the project-the project cash flow-throughout the life of the project from its conception to the end of some defined period of operation, a period that may extend over many years.
The promoter of a capital project invests money in the realization of that project in order to either provide a service or to product goods. The project is conceived and developed to meet a predicted demand of the service or goods.
Return obtained:
-benefit to the users.(hospital,motorway)
-profit to the investors
-provide statutory service and make a small profit.(power station)
The promoter will employ specialists to design and manage the development of the project.
Architects,land agents, and engineers are but three of the disciplines involved.
The promoter may also enter into a legal agreement or contract with a contractor, or a number of contract, for the construction of the project.
The promoter may also, therefore, be called the client or employer.
He is concerned with the flow of money to and from the project-the project cash flow-throughout the life of the project from its conception to the end of some defined period of operation, a period that may extend over many years.
1.2 The stages of a project
The three distinct stages of a project :
1. Appraisal
2. Engineering
3. Operation
Appraisal. Demand for a service or product must be explored, the location and size of the plant or building defined, and the cash flow predicted. A large number of variable factors need to be considered. (multitude of political and environmental aspects).
Throughout the appraisal stage the promoter is not commited and can abandon the project at any time having incurred relatively modest expenditure. This situation changes at sanction, when a scheme evolved from all appraisal studies is approved.
Engineering. The whole of the engineering phase is governed by the decision made by the promoter when sanctioning the project. Design will normally be undertaken by the promoter or his consulting engineeer in an office remote from the construction site. A substantial amount of information, in the form of specification and drawings relating to the work to be completed in each contract, must be generated by the designers and included in the documents issued to tendering contractors so that they may compile and submit a realistic price for work.
1.3 Organization of the construction industry
The construction industry is involved in 3 basic types of work, each with diffrent and distinct charateristics and,consequently, with substantial differences in the organization of work and in contractual relationships.
Building work is frequently repetitive and generally above ground level with structural safety and aesthetic considerations tending to dominate the design process.
Civil engineering is mainly concerned with roadbridges, railways, tunnels, marine structure, and water works. Each project is normally a unique design, and the emphasis on control of water and on working below ground level implies that there may be a great element of risk and uncertainty. The promoter will normally engage a consulting engineer who is expert in the particular type of construction. It is normal for this engineer to undertake all design work, to supervise the working of the contractor(s), and to manage the realization of the project. The contractor is then employed (as in building) only to construct the works.
Process plant erection is the third branch of the construction industry. Here the promoter will normally be expert in the design and operation of the plant and will frequently undertake both the basic design and management of the project. The contractor will then be responsible for detailed design, manufacture, site fabrication, and erection of the plant units. The contract may require that the plant offered and erected by the contractor shall achieve a specified operating performance. Much of the site work is repetitive,e.g.,erection and lagging of pipework, and is labour-intensive.
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