# Assessing and Priorities Delay Factors of Prefabricated Concrete Building Projects in China
## 6 Conclusions  
Overall, prefabricated construction has been considered a widely accepted alternative to conventional cast-in-situ concrete construction since it is capable of offering numerous benefits for investors and contractors. However, delays frequently occur in prefabricated concrete building projects, despite strong efforts to improve project schedule estimation and control. Thus, the delay factors of prefabricated construction should be identified and analysed to improve its scheduling performance. As one of the multi-criteria decision making techniques, ANP is capable of making accurate calculation of criteria priorities and their relations. Meanwhile, DEMATEL is a useful method for analysing and quantifying cause-effect relationships. Thus, integrating DEMATEL with ANP can effectively identify the critical attributes and evaluate the weights of criteria. Many fields are showing increasing interest in utilising the DEMATEL-ANP method for multi-criteria decision-making; however, a synthesised risk assessment based on the DEMATEL-ANP method had not yet been addressed in construction projects of prefabricated concrete buildings before this research. This paper utilised the combination method for investigating the cause-and-effect relationships among the delay factors and prioritising the key delay factors in terms of their importance in the Chinese construction industry. The DEMATEL model facilitated the evaluation of the extent to which each factor impacts other delay factors. The quantified extents were then converted into a prioritisation matrix through ANP. Twenty-four risk factors have been selected from a literature review and categorised into seven dimensions. Questionnaires have been chosen as data source to assist in the practical application of the method in the prefabricated construction.  
The results reveal that 'inadequate worker experience' has the most significant impact on the other factors and 'inefficient structural connections for prefabricated components' is the most easily affected by the most delay factors in the Chinese construction industry. In addition, the global weights indicate that 'inefficient structural connections' is considered the most significant indicator. Other major delay factors, including 'lack of communication among participants' and 'low productivity', should also be included in the scheduling control. Overall, this research contributes an assessment framework for decision making in the scheduling management of prefabrication construction. This research is expected to be further improved by incorporating broader data sources and including more delay factors in future research.  
Conceptualization, Y.J., L.Q., Y.L. and X.L.; Methodology, Y.J., L.Q., Y.L., X.L.; H.X.L. and Y.L.; Formal Analysis, L.Q. and Y.L.; Writing-Original Draft Preparation, L.Q. and Y.L.; Writing-Review & Editing, H.X.L. and Y.L.; Funding Acquisition, Y.J.  
The authors are thankful for the support from the National Key R&D Program of China (2016 YFC0701810 in 2016 YFC0701800), North China University of Technology Science and Technology Innovation Project (188 XN149), and North China University of Technology Yu Jie Talent Development Program (18 XN154).  
The authors declare that there is no conflict of interest regarding the publication of this paper.