土木工程英文文献

KSCE Journal of Civil Engineering (2011) 15(1):23-31DOI 10.1007/s12205-011-0983-5

Construction Management

doc.guandang.net

Productivity Management Methodology Using Productivity Achievement Ratio

Tae Wan Kim*, Hyun-soo Lee**, Moonseo Park***, and Jung-Ho Yu****

Received September 8, 2009/Accepted April 8, 2010

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Abstract

Although construction productivity has received a great deal of attention from construction practitioners and researchers, fewresearch efforts have specifically evaluated productivity in the context of the productivity management cycle. Consequently, there isstill a lack of useful indicators for determining which items should be prioritized and improved upon in order to yield the highestbenefits from productivity management. In an effort to address this issue, this study proposes the Productivity Achievement Ratio(PAR), which is a productivity evaluation indicator that will assist in the selection of the most appropriate management items forconstruction productivity enhancement. Using a multiple linear regression analysis, the process for calculating the PAR is developed,and the applicability of the proposed indicator is verified through a case study of steel erection work. The results of this study indicatethat the PAR can aid construction practitioners in achieving more balanced and effective productivity management, even whenmanagement resources are limited.

Keywords: productivity, productivity management, reduction factor, productivity achievement ratio, regression analysis

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1. Introduction

Productivity-one of the major factors used in measuring in-dustry outcomes-is defined as the relation between a productionsystem output and the input set in that system. The importance ofmanaging productivity has long been emphasized in the con-struction industry, and a considerable amount of research hasbeen conducted on the issue. Sumanth (1984) argued that bothmanagers and employees should pay close attention to produc-tivity management and that the productivity management cyclehas four phases: measurement, evaluation, planning, and impro-vement, as depicted in Table 1.

There have been many research efforts to examine pro-ductivity measurement and consequently contribute to the better

Table 1. Work in Each Phase of Productivity CycleCycleMeasurementEvaluationPlanningImprovement

Contents

Focusing on calculation of productivity value by measurer’s definition and scope.

Estimating the amount of productivity change between two discrete periods.

Devising short and long-term plans in regards to future productivity

Performing actual productivity improvement process using several methods.

productivity management (Heap, 1987; Herbsman and Ellis,1990; Thomas and Zavr ki, 1999). However, despite yieldingdecent estimations of productivity, these studies have rarelyidentified which items require the most attention for optimalproductivity management. Indeed, productivity has commonlybeen estimated by the ratio between system output and inputwithout consideration of the particulars of each work item.

Considering each work item when measuring productivity is acomplex process. For instance, it must be taken into account thatwork items associated with low productivity do not always havehigh potential for improvement. As well, a minimal change inproductivity does not necessarily signify the presence of a workitem linked with a poor management performance. To deal withthese complexities, an advanced productivity indicator, whichcan account for the unique characteristics of each item, isneeded.

For example, Table 2 shows the labor productivity associatedwith several types of formwork in an apartment project in Korea(Jung et al., 1995).

As seen in Table 2, the labor productivity of the euro form ·plywood form is 0.628 M2/Man·Day, while that of the prefabri-cated form is 0.707 M2/Man·Day. However, this fact does notdirectly indicate that the productivity management of the prefa-bricated form is better than that of the euro form·plywood form.It would also be inappropriate to conclude that the euro form û

*Ph.D. Student, Dept. of Civil and Environmental Engineering, Stanford University, CA 94305, USA (E-mail: tkim08@stanford.edu)**Member, Professor, Dept. of Architecture, Seoul National University, Seoul 151-742, Korea (E-mail: hyunslee@snu.ac.kr)

***Member, Associate Professor, Dept. of Architecture, Seoul National University, Seoul 151-742, Korea (Corresponding Author, E-mail: mspark@snu.ac.kr)

****Member, Assistant Professor, Dept. of Architectural Engineering, Kwangwoon University, Seoul 139-701, Korea (E-mail: myazure@kw.ac.kr)

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