Research On The Impact Of Rework On The Construction Project Cost In China

Rework is a common and serious problem in Chinese and international construction industries,which often leads to poor quality,cost overrun and delay.Therefore,effective rework management can achieve the goals of construction projects,increase industry profits,and save social resources.The investment of construction projects in China is huge,but the literature review results indicate that very few studies have been focused on this topic in China.Based on literature review,questionnaire survey and case study,this paper sets up three research goals:(1)identifying the primary causes for rework of construction projects in China;(2)evaluating the proportion of rework costs in the total project contract amount;(3)exploring the impact of different causes on rework costs.The thesis consists of six chapters.The first chapter is the introduction,including the background,purpose,significance,method and content of research.The research flowchart is established.The second chapter is the basic theory of rework cost;Chapter 3 identifies the causes for the rework of the construction project through literature review,and establishes an index system;Chapter 4 is the questionnaire survey and data analysis,using SPSS22.0 to verify the reliability and validity of the questionnaire survey results.Then this paper carries out factor analysis,descriptive analysis and difference analysis;Chapter 5 is case study,through the collection and analysis of 3 case projects.The results were cross validated with the results of the questionnaire survey.Chapter 6 summarizes conclusions,limitations and future research directions.In this study,148 questionnaires were collected,among which 133 were valid questionnaires,with a valid rate of 89.86%.Combining the results of the three case studies,the main conclusions are followed:(1)From the perspective of different project stakeholders(client,contractor,designer,and others),a total of 28 rework causes were identified.The six most critical factors of the rework causes are: unqualified construction materials(4.26),design errors(4.15),design omissions(4.10),misunderstanding of design intent(4.08),poor workmanship(4.01)and scope change(3.99).(2)The rework cost accounted for 3.56% of the total project contract value.Among them,the rework cost caused by the client accounts for 30.74% of the total rework cost,followed by the contractor(25.56%)and designer(18.18%).(3)The six factors that have the most significant impact on costs are: scope change(7.80%),poor design coordination(7.66%),specification change(6.83%),and unqualified construction materials(6.53%),misunderstanding of design intent(6.35%),poor workmanship(6.13%).The research findings of this paper are valuable to improve the ability of the project stakeholders in managing rework,achieving project success,saving resources and enhancing efficiency and profit in China.