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CH 5 PRECONSTRCUTON . Team work : Jehad Khalaf Ehab Esheach Raed Shehada Khalil Abu Eed Supervisor: Dr. Kamalin Shaat. Construction Management Department ,Islamic university. CHAPTER CONTENT. 1. INTRODUCTION. 2. CONSTRUCTION SITE CONDITION. 3. AREA CONSTRUCTION PRACTICE . 4.
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CH 5PRECONSTRCUTON Team work : JehadKhalafEhabEsheach RaedShehadaKhalil Abu Eed Supervisor: Dr. KamalinShaat Construction Management Department ,Islamic university
CHAPTER CONTENT 1 INTRODUCTION 2 CONSTRUCTION SITE CONDITION 3 AREA CONSTRUCTION PRACTICE 4 PRELIMANRY ESTIMATE 5 WORK PACKAGES 6 VALUE-ENGINEERING PROGRAM 7 CONSTRUCTION PLANNING
INTRODUCTION This chapter emphasize the role of the professional construction manager in preconstruction planning. Planning aims at workable program that will achieve project goals and serve as standard against which actual progress can be measured.
OWNER CONTRACTOR Coordination DESIGNER
After the PCM has obtained through knowledge of job –site condition that will affect performance of work ,preparation of work plan . Summary Schedules Preliminary estimate Title Work Plan Value –engineering program Construction planning Work Packages
CONSTRUCTION SITE CONDITION • AREA INVESTIGATION • The items to investigate on the site many and varied • Many general contractors,design-constructions,developer • & subcontractor have considerably more detailed similar checklists.
AREA INVESTIGATION (items) Site Description (Vegetation ,trees, terrain ,depth of topsoil ,drainage ,existing utilities ,access). 2. Utilities Serving Site (Electricity ,gas, water ,sanitary sewer ,storm sewer ,railroad, highway, railroad sliding) 3.Builidng Department (contact ,telephone number, building code, plan check time ,fees ,zoning licensing ,etc) 4.Labor Unions wage rates, Expiration(Membership, manpower storage ,manpower surplus, current agreements , dates ,etc .)
AREA INVESTIGATION 5.Recommended Contractors (list recommended general and trade contractors for further consideration .) 6.Materials and Methods (list favored local materials including current quoted price for ready-mix concrete , Lumber ,imported granular base ,plywood ,masonry ,and other key items.) 7.Equipment Rental (list local prices ,or key local quotations,)
AREA INVESTIGATION 8.Climatological Data (list average maximum and average minimum temperature ,precipition,and other Significant data by months ) 9.Other Projects (visit other projects noting productivity ,favored methods ,favored materials ,Subcontractor,etc.) 10.General Appraisal (summarize results of site and area visit and recommend significant conclusion to betaken into account during the planning of the program .)
Note: PCM will approach of investigation of general condition ,exactly as would general contractor planning to bid of the work.
Foundation and Earth Conditions • Report Soil • Noting the soil engineer’s Proposed foundation recommendations. • Determine the desirability of a separate earthwork contract • and the board scope and the extent of contract . • Preliminary judgment can be made as methods that should prove most economical
Note : this approach mirrors that of potential bidder. If the contractor manager is not aware of the potential problems and difficulties ,meaningful estimate for the work cannot be prepared ,nor can a bid package be framed that will minimize uncertainties ,unneeded risks ,and hence the contingencies that would be included by bidders in their prices
General Planning • BY visiting the site Construction manger can : • See access roads ,railroads ,other factors firsthand • Chose areas for locating temporary facilities • Develop aprerilmenary plan for storage areas • Examine the existing electrical ,water ,and other service utilizes • Develop plan for site security • Alert for condition on the site .
Note : site visits are generally the only way that items of type described here can be taken into account in the overall program . Pcm must be able to communicate his on-site knowledge to the designer ,the owner ,and his own personal .
Local work practices and jurisdication: Area construction practice Equally important to the job –site investigation or even more important is the investigation of the normal method of doing business in the project local .it must be systematically review the local condition and practices. Local work practices and jurisdiction: The professional construction manager handling a phased construction program is constantly faced both with fitting his construction packages to the design schedule and with tailoring them to optimum size that will attract qualified contractor .
Labor cost productivity and availability : 1.Determine of craft productivity is difficult since it is varies considerably from contractor and from trade to trade . 2.To obtain conclusion we must discussion local contractor and labor union personnel and inspection of several projects in the area . 3.Farming work packages to utilize the relatively permanent craft workers can thus sometime have a significant economic benefit to the owner . 4.The manpower must be recruited by all contractor. 5.Key design decision can sometimes be influenced to change specification.
6.Collective bargaining agreement for all crafts should be obtained by the manager as early as possible . -These agreement will be used in determining wage rates to be used in estimate . -Forecasting productivity by revealing the presence or absence of restrictive work practic
Locally favored methods and material : • If the designer un familiar with local condition , investigation of local favored method and material , and there subsequent utilization where possible in the specification , can significant reduce project cost . • .It is very important investigation of local favored to used more economical local material and methods.
Key local prices: • Local price for standard items can be readily obtained.. • They are significant value in comparing alternative methods as well as in making the fair cost estimating , such local price include ready mix concrete, sand gravel ,lumber, reinforcing steel ,concrete blocks • - a precast concrete plant have developed standard section that are very economical when compared with other methods , put in other area the precast plant cant available.
Local contractors • The pcm must be develop representative list of qualified interested contractor for each proposed bid package . • The list should be large enough to ensure competitive • Pcm even if initially unfamiliar with the project area will have developed local contact who can give valuable information such union representatives ,contractor association , local architects and engineers and many other can give valuable assistance in prescreening available contractor .
Individual meetings with all interested contractor or by pcm is very important to accomplish the following . • - Explain the overall program for the project include number of individual bid packages. • - Review the preliminary procurement schedule and discussing the approximate • - Determine the interests of the potential bidder • -Discuss trade jurisdiction as applied to the particular contractor • - Obtain required information on previous jobs completed by the contractor if • Possible determine his present workload and obtain required financial information. • by comparing answer to questions from similar contractors ,he will also obtain accurate picture of how the construction business is conducted in the area .
Establishment of project field office: • The field office should be established in advance of the award the first contract. • The field construction manager will be the key representative in all dealing with local people.
Preliminary estimate • When the overall scope conceptual design evolved to the point where the manager has a reasonable idea of the requirements of the owner and the implementation program of the designer , preparation of a preliminary estimate can proceed. • the Preliminary estimate initially serves to check the design against the owner original budget or appropriation . • if the cost appear to be over budget alternative concepts can be explored through the value –engineering program. • the Preliminary estimate is also necessary for preparing a realistic overall project schedule that forecast occupancy dates and specifies completion schedules for individual construction contracts. • the preliminary estimate forms the basis for cost control during design and procurement.
Design and procurement schedules : -The schedule for each proposed bid package must be prepared showing the detailed design, specification period , package review , bidding period and evaluation period. -The schedule must be developed early and must be used by designer ,owner and manager in performing their assigned tasks. -Reasonable bid periods should be schedule by the manager. -Most designer will prepare an overall design schedule. -If the manager prepare the bid packages from plans and specification furnished by the designer areview period by owner and designer is equally important -This review period is generally the last chance to: Avoid errors Take advantages of recent knowledge Avoid later plan changes which result additional costs.
If sufficient time is planned from the beginning :- The schedules can be more easily met More competitive bids will normally be received -Reasonable period evaluation and award of each bid package should therefore be included in the schedule. See figure 5-1 design and procurement schedule
Work packages : After PCM has become thoroughly familiar with the project local Preliminary design schedule is developed Preliminary estimate is completed. -Bid package development is one of the most significant contributions of the PCM Two of many important factor that influence in this process- Constraint economy Design constraints.
1-CONSTRUCTION ECONOMY The scope of packages should be designed to be of assize that will prove most economical by stimulating competition that will minimize overall cost by avoiding unnecessary tiers of contractors and subcontractors. 2-DESIGNCONSTRANT Design constraint will modify the content of bid packages in balance will overall objectives.
VALUE. ENGINEERING PROGRAM: -The value engineering program must be acceptable and practiced by all member of the project team owner , designer and manager but the main role related to PCM. -The function is analysis during all phases of program , especially in planning , design ,bidding award phase. Value engineering analysis consideration in three phases.- Conceptual phase Detail design phase Procurement phase.
Conceptual phase -The manager and the designer can explore basic concept, and list possible alternative solutions. -If the PCM historical cost data tabulated , alternative comparable cost estimate can be prepared quickly and economically . Example On one project ,a simple low cost study of precast double tee –wall section , tilt up concrete slab ,and concrete block walls , showed that the precast double tee walls less expensive and structurally equivalent and more pleasing.
2-DETAIL DESIGN PHASE : PCM will keep an up to date book , indexed by Standard architectural specification section Listing alternative materials and methods Cost from previous jobs.
CONSTRUCTION PLANNING Basic construction planning during or before detailed design phase includes organization charts, staff schedule, temporary facilities requirement, selection of particular individuals to be assigned and delineation of their responsibilities.
1- TEMPORARY FACILITIES -An important phase of construction planning is the analyzing of temporary utilities and general conditions required. -Temporary utilities can be furnished by the owner, be built into individual contract package or obtained from others based on local practice and job site conditions. - Successful CM have to visit the site (area) and develop the knowledge and skills necessary to plan temporary facilities requirements. - Successful general contractors and CM have developed the knowledge and skills necessary to planning temporary facility requirements and perform general conditions item in a manner most economical for project.
2- PROCEDURE OUTLINE - Each project is unique. - CM most advantages is its flexibilities. - CM must be able to assess the conditions and problems as they develop and react without delay. - The three parties must understand each others responsibilities.
3- CASH FLOW REQUIREMENT - An estimate of cash flow requirements for the project can be readily prepared from preliminary estimate and from summery schedule. - A simple cash flow projection based on prior planning can be prepared as a part of control package. - Net cash estimate can be prepared taking into account investment income , retained funds ,and the lag between billing and payment requirements. - Public works are often funded by bond issues. - Public agencies and most large owners can obtain funds at lower interest rate than most contractors. - Minimizing retained funds can often benefits owners in receiving lower bid prices by minimizing contractor interest expense. - General contractors, design construction ,developers and subcontractors use cash flow schedules to determine the capital requirements for each project . - The overall company cash flow projection is important in determining working capital requirements for the firm and in setting up lines of credit to borrow funds at favorable rates. .
SUMMARY - Planning must be based upon facts if project goals are to be achieved. - CM must understand the overall objective of the owner and overall concepts of the designer. -Each area and locality has its own construction peculiarities.. - Program ,method and materials developed for certain sections of the country are totally inappropriate For other localities because of the vastly different condition that affect the work. - In planning stage all portion of the project are developed in straightforward and logical manner consistent with project knowledge and anticipated condition. - Planning and design phase of construction project ,planning will include the preparation of preliminary estimate and design , procurement and construction schedules. - Unanticipated events impact upon the project , the plan must be changed to fulfill its primary function .. .
Thank You! Team work