Perception Variance of TACT Productivity between General Contractor and Subcontractors

Abstract

To complete various types of finish works with higher quality in much less time, TACT, which was mostly used for high-rise buildings, has been adapted to meet the needs for systematic schedule management in construction sites. However, the effectiveness of adapting TACT has not been shown as expected due to the different perspectives on productivity from both general contractor and subcontractors based on unforeseen conditions according to the types of site. Furthermore, not enough theoretical backgrounds, empirical data, and systematic approaches to solve the fundamental problems caused by each participants different views on productivity has produced obstacles for establishing effective solutions. Therefore, this research aims to analyze the main possible reasons for having different point of views regarding productivity among the various participants of construction sites using TACT based on literature review, site survey, and interviews. Also, a case study was conducted to propose obtainable productivity (OP) regression equation and productivity achievement ratio (PAR) with reduction factors (RFs) and actual productivity (AP) data from an actual construction site. The proposed outcome may assist general contractors converting output management with PPC to productivity management with actual data using PAR. On the other hand, subcontractors would be able to estimate theory-based maximum productivity of construction sites with TACT by using OP. The PAR will enhance the communication between general and sub-contractors for their decision making process. Finally, the main RFs derived from PAR could be used as essential keys for productivity management to increase the economical and operational effectiveness of the construction project. The CC value is implemented with regression equation from the OP computation process for participants limitation factors and coefficient of regression. Using the implementation, the priority of the productivity management factors was evaluated. The research founds the theoretically explanation for perspective variance from the TACT productivity participants aspects. Also, the TACT application cases were compared with traditional cases to demonstrate the impact of scheduling methodology on productivity efficiency. The continuous productivity measures on site will more accurately resolve OP and PAR values, managing the productivity from the participants perspectives.