Improved Escalation Method for the Cost Estimation System using Previous Bid Price in Public Construction Projects

In Turkey, for the preliminary construction cost estimation, a notice, which is updated and published annually by Turkish Ministry of the Environment and Urbanism, known as “unit area cost method” (UACM) is generally employed. However, it’s known that the costs obtained through this method in which only construction area is taken into consideration have significant differences from actual costs. The aim of this study is to compare the cost estimations obtained through “multi layer perceptron” (MLP) and “radial basis function” (RBF), which are commonly used artificial neural network (ANN) methods. The results of MLP and RBF were also compared with the results of UACM and the validity of UACM was interpreted. Dataobtained from 232 public construction projects, which completed between 2003 and 2011 in different regions of Turkey, were reviewed. Consequently, estimated costs obtained from RBF were found to be higher than the actual costs with a 0.28% variance, while the estimated costs obtained from MLP were higher than actual values with a 1.11% variance. The approximate costs obtained from UACM are higher than actual costs with a 28.73% variance. It was found that both ANN methods were showed better performance than the UACM but RBF was superior to MLP.

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The Research and Development of Mechanical Product Turning Processing Cost Estimation System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.121-126.3612 ◽

2011 ◽

Vol 121-126 ◽

pp. 3612-3616

Author(s):

Wen Quan Huang ◽

Kai Shi Li ◽

Hai Jun Liu

Keyword(s):

Cost Estimation ◽

Manufacturing Cost ◽

Cost Information ◽

Development Environment ◽

Improve Design ◽

Market Competitiveness ◽

Processing Cost ◽

Estimation System ◽

The Cost ◽

Time Standard

This paper adopts the method labor time standard, in the development environment of VC++, using Access database storage costs data, and the cost results output into Excel, developed mechanical product turning processing manufacturing cost estimation system. Using this system can realize turning processing cost estimation and feedback the cost information of mechanical product turning processing, make a design personnel to understand the cost information, to improve design, reduce the cost, improve the market competitiveness of products

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Cost prediction model based on system dynamics in water resource project

MATEC Web of Conferences ◽

10.1051/matecconf/201925802027 ◽

2019 ◽

Vol 258 ◽

pp. 02027

Author(s):

Hirijanto ◽

I Wayan Mundra ◽

Addy Utomo

Keyword(s):

Prediction Model ◽

Cost Estimation ◽

Construction Projects ◽

Model Simulation ◽

Secondary Data ◽

System Dynamic ◽

Cost Prediction ◽

Cost Component ◽

The Government ◽

The Cost

Project’s cost is one of important components in project achievement. Because of the uniqueness of construction projects, cost estimation always differs from project to project. The rate of cost components always change over time make difficult to forecast the cost for the upcoming project. The cost component consists of many influencing variables where there is interrelationship each other affecting to the total project cost. This paper objective is to develop a cost prediction model to assist the project planners in cost estimation for future projects. System dynamic is one of the appropriate methods to analyse system behaviour with interrelationship referring to the historic data, so it is able to predict the future project. Developing the model, primary and secondary data are collected from previous studies, interview with the government planner and survey in Malang Regency. The model simulation is Brick work unit with its components. Data from last thirteen years are used to verify and validate the developed model by causal loop diagram as a basic method in system dynamic. The finding showed that the model is closed to real condition through the validation mechanism. The developed system is useful in decision making of budget planning based on work quantity.

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The Analysis of Cost Estimation using Cost Significant Model on Bridge Construction in South Sulawesi

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/921/1/012073 ◽

2021 ◽

Vol 921 (1) ◽

pp. 012073

Author(s):

E Aprianti ◽

S Hamzah ◽

M A Abdurrahman

Keyword(s):

Regression Analysis ◽

Cost Estimation ◽

Construction Projects ◽

Steel Frame ◽

Bridge Construction ◽

South Sulawesi ◽

The Cost ◽

Total Project Cost ◽

Total Project ◽

Significant Model

Abstract One of the fundamental problems faced by the province of South Sulawesi is the factor of accessibility, so the role of bridges is quite important. For this reason, the budget planning for standard bridge construction projects also needs to be efficient in terms of preparation and accurate in terms of budget. The Cost Significant Model is one of the total construction cost estimation models that relies more on the prices that have the most influence on the total project cost as the basis for estimation. In general, this study uses data from steel frame bridge construction projects in South Sulawesi Province to formulate a mathematical model with linear regression analysis so that it can be used in the process of estimating similar projects going forward. The Estimation Model which is formed from the regression analysis and the Cost Significant Model in this study, namely; Y = 3.884 (X7) + 0.989 (X8) - 65515.372. With; Y = Estimated Total Cost (Rp/m); X7 = Reinforcement Work Cost (Rp/m); X8 = Steel Frame Structure Work Cost (Rp/m). Where this model can explain 99.7% of the total project cost with a cost model factor of 1.038. The level of accuracy (percentage error estimate) of the estimation results of the Cost Significant Model in this study ranges from - 1.46% to +2.45%.

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Efficient Procedure to Scheduling Construction Projects at the Planning Phase

Baltic Journal of Real Estate Economics and Construction Management ◽

10.2478/bjreecm-2019-0004 ◽

2019 ◽

Vol 7 (1) ◽

pp. 60-80 ◽

Cited By ~ 1

Author(s):

Matiwos Tsegaye

Keyword(s):

Cost Estimation ◽

Construction Projects ◽

Cost Optimization ◽

Efficient Procedure ◽

Start Date ◽

Time Optimization ◽

Planning Phase ◽

Short Period ◽

The Cost ◽

Construction Schedule

Abstract The construction industry is one of the most important activities that contributes towards the economic growth of any nation. However, the sector has been experiencing problems of cost and time overruns, particularly the problems are significant for the lowest-bid awarded construction projects in the developing countries where inappropriate planning is reported to be one of the major causes. Thus, the paper aims at developing an integrated scheduling approach for construction projects during the planning phase from a project owner’s perspective. The proposed approach integrates cost estimation and schedule in light of practical activity precedence and mathematical cost optimization using different project commencement dates. The study has shown that cost and time optimization model could yield impractical results unless double precedence relations (start-to-start plus finish-to-finish) are imposed between some activities such as trench excavation and pipe laying. It has also demonstrated that the cost and time budgeted during the planning phase would substantially deviate from actual if the planned construction start date slips from the plan, particularly for short period projects. The proposed approach demonstrated in the paper can sufficiently allow planning engineers to develop a comprehensive construction schedule so that the cost and time overruns in the lowest-bid awarded construction projects can be reduced. The paper provides empirical insights into how a robust construction schedule is developed from an owner’s perspective. Cost-time optimization and risk analysis results obtained from manual computation might reduce the reasonable accuracy of the desired cost and schedule integration unless each activity is assigned its own calendar.

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Automatic Estimation System of Building Frames Integrated with Structural Design Information (AutoES)

Modular and Offsite Construction (MOC) Summit Proceedings ◽

10.29173/mocs160 ◽

2015 ◽

pp. 224-231

Author(s):

Chaeyeon Lim ◽

Donghoon Lee ◽

Won-Kee Hong ◽

Sunkuk Kim

Keyword(s):

Cost Estimation ◽

Structural Design ◽

Construction Costs ◽

Building Frames ◽

Design Information ◽

Automatic Estimation ◽

Project Participants ◽

Estimation System ◽

The Cost ◽

Structural Engineers

The project participants, including clients, architects, structural engineers and contractors would want to know accurate construction costs as soon as the design is completed. However, it may take at least several weeks for the cost estimation after the structural design and drawings are completed, depending on the project scale or size. Quantity surveying in manual is time-consuming and taken by lots of effort. Even if computerized software is used, it takes a lot of time to insert structural design information to the software. In addition, the estimated cost may result in inaccurate quantity owing to the drawing errors or quantity surveyors’ mistake, as well as it is not an exact quantity for actual construction, exposing numerous problems at the construction phase. For instance, to accurately estimate the quantity of rebar, some additional effort is required such as preparing the bar bending schedule. Such problems occur by the communication gap and viewpoint difference among project participants who perform structural designs, draft the structural drawings and estimate quantity. But, if structural design information can be automatically received for quantity estimation, an exact quantity can be estimated without omission or errors. To solve those problems, this study proposes automatic estimation System of building frames integrated with structural design information (AutoES). Using the algorithms provided by AutoES, the task of cost estimation can be accomplished with an exact bill of quantity including a bar bending schedule without errors, mistakes, or omission within a week, which used to take at least 4 weeks.

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Determining The Effects Of Awarding Lowest Bid Price System On The Construction Projects Of Ethiopian Southern Nation

Journal of University of Shanghai for Science and Technology ◽

10.51201/jusst/21/121032 ◽

2022 ◽

Vol 24 (1) ◽

pp. 253-260

Author(s):

Ashenafi Reta ◽

◽

Ashebir Alyew ◽

Keyword(s):

Construction Industry ◽

Construction Projects ◽

System Construction ◽

A Value ◽

Maximum Value ◽

High Incidence ◽

Bid Price ◽

Public Construction ◽

Construction Works

Identifying the effects of low bid award system in construction projects can be used as benchmark to find alternative method to low bid award system in the future of construction industry. The results of questioner survey conducted to determine the effects of awarding lowest bid award system in construction projects of Ethiopian southern nation are presented in this study. Personnel from consultants, owners and contractors are among the survey`s respondent. The result of the study outlines promote transparency, avoid fraud and corruption, promoting competition amongst contractors, excessive time overrun, compromise quality and hindering profitability of contractors as the top ranked effects of low bid award system. Construction industry participants have started recognizing that accepting the least price bid does not guarantee maximum value. Achieving a value-based procurement approach is a challenge, particularly for the Pakistani public sector clients, who are limited in their ability to evaluate the competitive bids based solely on the lowest-bid award system. Persisting problems of inferior quality of constructed facilities, high incidence of claims and litigation, and frequent cost and schedule overruns have become the main features of public construction works contracts. This research was undertaken to assess the performance of public owned construction projects awarded on a lowest bidder bid awarding system.

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FACTORS AFFECTING COST OVERRUN IN CONSTRUCTION PROJECTS

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.2021.8(1).cpm-14 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Mohammed Algahtany

Keyword(s):

Saudi Arabia ◽

Construction Projects ◽

Cost Overrun ◽

Cost Overruns ◽

Factors Affecting ◽

Public Projects ◽

Low Performance ◽

Major Factors ◽

Public Construction ◽

The Cost

Public construction projects in Saudi Arabia have been suffering from low performance for the past decade. Cost overrun is one of the most important issues in project’s performance and is nearly associated with most of public projects. The aim of this study is to identify and assess the major factors leading to cost overruns in education construction projects in the Northern Province of Saudi Arabia to minimize the risks’ effects in future projects. The research methodology started by identifying cost overrun factors through literature review, project’s documentations, and experts’ interviews. Professionals who worked at the construction projects undertook a questionnaire survey to investigate the importance of the cost overrun factors. The top factors of cost overrun were identified through the analysis of the factors’ occurrence and severity. The study main results included the top causes of cost overrun which are delay in contractors’ progress payment by client, difficulties in financing project by contractor, delays in sub-contractor’s work, additions of quantities such as excavation, backfill, and concrete works, and bid award for lowest price. The investigated risks in the study should be evaluated and mitigated in future projects to minimize their effects and enhance the industry performance.

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THE FORMATION PROCEDURE OF THE ESTIMATED CONSTRUCTION COSTS OF ROOM FUNCTION GROUPS

Экономическая наука сегодня ◽

10.21122/2309-6667-2018-8-315-321 ◽

2018 ◽

pp. 315-321

Author(s):

N. SAMAL

Keyword(s):

Cost Estimation ◽

Capital Investment ◽

Construction Projects ◽

Building Construction ◽

Preliminary Design ◽

Construction Costs ◽

Investment Volume ◽

Calculation Methodology ◽

Definition Of ◽

The Cost

The article is concerned with the problem of cost estimation for multifunctional construction projects on the stage of pre-investment feasibility study. For addressing issues such as the definition of capital investment unto the property assets the author considers the procedure of construction cost estimation on the base of the cost indicators of room function groups. On a research basis the author has developed the calculation methodology of the cost indicators of room function groups. Room function groups present the assembly of spatially connected facilities and communication passages which are focused on define operations functions accomplishment. There is the procedure of the application of room function groups costs for the definition of the investment volume in building construction in the phase of poorly detailed preliminary design.

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Composite Criticality in Machinery Fleet Management of Construction Projects

MATEC Web of Conferences ◽

10.1051/matecconf/202031202003 ◽

2020 ◽

Vol 312 ◽

pp. 02003

Author(s):

John-Paris Pantouvakis ◽

Alexander Maravas

Keyword(s):

Cost Estimation ◽

Construction Projects ◽

Fleet Management ◽

Construction Operations ◽

Construction Machinery ◽

Activity Duration ◽

Machine Reliability ◽

Worker Performance ◽

The Individual ◽

The Cost

During construction operations, fleet management aims at maximizing the uptime and efficiency of construction machinery while also minimizing the cost of ownership through lifecycle planning and management. In the deterministic approach, the theory suggests that one type of machinery is considered to be critical. However, taking into account the real circumstances under which projects are performed with issues such as machine reliability, worker performance, and/or errors in estimating the scope of work, it is evident that there are significant limitations to the existing approach. Hence, to address this issue, uncertainty in fleet productivity is modelled with fuzzy set theory. In this context, the notion of composite criticality under which the productivity of a fleet depends on more than one type of machinery because of the fluctuations of the individual productivities is introduced. To this purpose, a simple case study is presented to illustrate this concept. It is concluded that this approach leads to a better understanding of the estimation of activity duration and cost estimation which in turn means better project scheduling and financial planning.

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