Integrated Risk Management Framework for Tolerance-Based Mitigation Strategy Decision Support in Modular Construction Projects

Tolerance Management in Construction: A Conceptual Framework

“…There are two types of tolerances: (a) Dimensional tolerances, stating the permitted amount of deviation for a specific size, e.g., floor thickness, and (b) geometric tolerances, stating the allowed amount of deviation on a specific geometric property, e.g., flatness of concrete slabs [36,37]. TM in construction is about utilising various tools and methods [4] to: (a) Minimise tolerance problems derived from dimensional and geometric variations by proactively identifying and mitigating risks related to the likelihood of an occurrence of tolerance problems, called tolerance risks hereafter [27,38], (b) ensure constructability of design, operating capability, and structural integrity [39][40][41], and (c) reduce lead times by avoiding tolerance problems and the associated modification process [20]. The ultimate aim of TM is to minimise costs [42], increase quality [43], and continually improve the management of tolerances [16].…”

“…The synthesis of the literature identifies that TM in construction falls into four stages, namely: Identification of tolerance requirements/risks, called 'IDENTIFICATION' hereafter [5,15,20,27,38,57,58]; planning the achievement of tolerance requirements/mitigating tolerance risks, called 'PLANNING' hereafter [5,15,17,20,27,38,[57][58][59]; communication of tolerance information, called 'COMMUNICATION' hereafter [5,15,18,20,27,38,40,[57][58][59]; and tolerance compliance control, called 'CONTROL' hereafter [17,20,27,40,57,60]. For clarity, tolerance requirements concern dimensional and geometric properties of components [37].…”

“…In this paper, the propositions to improve TM in construction [5,15,17,18,20,27,38,40,[57][58][59][60]62] were collated and categorised into four TM stages (IDENTIFICATION, PLANNING, COMMUNICATION, CONTROL), and are critically reviewed. Such categorisation is essential to help improve TM [86,87], however, the categorisation of TM stages in construction does not presently exist in the literature, and hence is a contribution from the research here presented.…”

“…The explored TM process was considered as a good practice because its implementation does not require the application of costly methods and understanding of theories adopted from manufacturing, as opposed to most of the existing solutions in the literature [4,11]. In essence, such proactive process with the focus on tolerances in design avoids reactive approaches (i.e., fixing tolerance problems on site) [13,27]. As it can be seen from Figure 2, the process includes all of the TM stages and is applicable from project inception to project completion, unlike most of the existing solutions [4,20,88].This confirms the importance of having a proactive process for TM that involves all the stages to reduce remedial actions during construction [15,17,20,24,25,38,40].…”

“…Tolerance problems are traditionally dealt with at the time and place of the construction work, and the way they are modified (e.g., shimming, grouting, reaming holes, applying forces) to a great extent hinges on the labourer's experience and in situ capabilities rather than on a systematic process [20,22,24]. Despite the importance of tolerances, the construction industry currently is argued to lack a systematic and practical process for tolerance management (TM) to provide designers and practitioners proactive insight into avoiding tolerance problems [12,[25][26][27].…”