Analysis of schedule deviations in road construction projects and the effects of project physical characteristics:

摘要

Purpose: This study aims to investigate the schedule deviation in road construction projects and the effect of project physical characteristics on schedule deviations. The study also addresses the main factors affecting time deviation in road construction projects. Design/methodology/approach: The study is based on a sample of 101 road construction projects awarded in the West Bank in Palestine over the years 2010-2015. The study investigates the time deviation in total project duration and the deviations in major activities of road construction projects: earthworks, base works and asphalt works. Based on the collected data, regression models are developed to show the relation between actual duration and estimated duration. The study also investigates the effect of project physical characteristics on time deviation through regression analysis. The considered characteristics are: project size, terrain conditions, ground conditions and soil quality. To identify the main factors affecting time deviation, a survey of 40 contractors and 30 consultants was performed. Findings: The study reveals the following: average of time deviations in earthworks = 46.48 per cent, average of time deviation in base works = 29.66 per cent, average of time deviation in asphalt works = 23.43 per cent and average of time deviation in total duration = 47.72 per cent. Regression models that investigate the effect of physical project characteristics (i.e. project size, terrain condition, ground condition and soil quality) on time deviation are discussed. The survey reveals that the top five factors affecting delay in road construction projects are political situation, payments delay by the owner, lack of coordination between construction parties, frequent change orders and unexpected ground condition and terrain. Originality/value: This study investigates the schedule deviation in road construction projects and the effect of project physical characteristics on schedule deviations. The study also addresses the main factors affecting time deviation in road construction projects. The study is based on field data collected from 101 road construction projects and a questionnaire survey conducted in the West Bank in Palestine. Based on the findings, a number of recommendations are formulated to control the problem of time deviation in construction projects. Although this study is specific to the country of Palestine, its results can be applicable to other developing countries facing similar problems in their public construction sectors.