# Assessing and Priorities Delay Factors of Prefabricated Concrete Building Projects in China
## 1 Introduction  
Prefabricated construction refers to the practice of designing and fabricating building elements in manufacturing factories, transporting the elements to construction sites, and assembling the elements to a greater degree of finish for rapid site assembly compared to traditional piecemeal on-site construction [1; 2]. Thus, interchangeable terminologies associated with prefabricated construction in the existing literature include off-site construction [3], off-site prefabrication [4], off-site manufacturing construction [5], and off-site production [6]. Prefabricated concrete construction is considered a widely accepted alternative to conventional cast-in-situ concrete construction since it offers numerous benefits for investors and contractors, such as higher speed of construction, enhanced quality outputs, higher tolerances, lower costs, reduced labour re-works on-site, and safer construction environments [7; 8; 9]. From the perspective of environmental sustainability, prefabricated concrete construction benefits in waste reduction [10], facilitates the reuse of some components [11] and reduces water consumption [12]. The above-mentioned merits have significantly contributed to improving construction industries in developed and developing countries [13]. In particular, precast technologies have been greatlydeveloped to meet the requirements of sustainability and housing demand in China [14]. China has also embarked on several initiatives to promote prefabrication [15]. However, in comparison to conventional on-site construction, there are also notable disadvantages that should be considered, such as structural changeability, transportation restrictions, and span limits [16]. In particular, prefabricated concrete construction requires increased and more detailed coordination at all stages of a project (because of more construction phases, more complicated construction techniques, and more stakeholders), which increases the difficulty in progress monitoring and planning for construction management tasks. Unlike the traditional construction methods, researchers and engineers are advised to pay particular attention to schedule risks of prefabrication construction projects before the construction stage [17]. For example, [PERSON] et al. [18] utilised a fuzzy analytical hierarchy process approach for ranking project risks associated with modular construction. The results revealed that the control schedule in the design stage is an important factor with respect to project duration owing to a relatively high weighting value. Also, few studies have investigated stakeholder-related risks and their cause-and-effect relationships prior to the construction stage. Therefore, [PERSON] et al. [17] employed a social network analysis to recognise and investigate the underlying network of stakeholder-associated risk factors in prefabrication housing construction projects. They emphasised the information-related risks and indicated that the design information gap between designers and manufacturers may result in frequent delay in projects [19]. Moreover, the efficient manufacturing of building elements is vital to delivery deadlines. [PERSON] et al. [20] adopted a simulation-based auction protocol framework to effectively schedule modular construction projects with limited data available. To monitor and visualise the work progress of off-site activities, Building Information Modelling is considered an effective and practical tool [21]. Overall, delays frequently occur on prefabricated concrete building projects, despite enormous efforts toward project schedule estimation and control. Researchers have also realised that construction delay is a primary barrier to the adoption of prefabricated construction in many nations [22]. It is, therefore, worthwhile to explore some strategies for avoiding schedule delays in prefabricated building projects and minimising schedule delay risks in the Chinese construction industry. In addition, previous research confronts several challenges.