| dc.description.abstract | With the increasing number of old buildings, repair projects have become a major focus in engineering execution. However, delays in repair projects are common, and there still needs to be more relevant research in this area in Taiwan. It is important for project implementers to meet contractual requirements and user needs in order to have a good schedule plan. This study analyzed the causes of schedule differences between as-planned and as-built schedules in actual cases.Based on the analysis of actual cases and expert feedback, this study concludes the following two findings: First, the main reasons for the increase in the duration of repair projects are: (1) poor construction flow and lack of proper construction planning; (2) changes due to on-site conditions; (3) unclear communication and confirmation of requirements; (4) lack of pre-existing knowledge of buried items underground (wall surfaces) and inadequate pre-design (pre-construction) surveys; (5) insufficient expertise of relevant personnel. Second, effective methods to address the increases in the duration of repair projects are: (1) When contracting the project, the contractor should confirm the actual site conditions and complete the drawing work. During the pre-construction coordination meeting, clarifing and taking corresponding measures are required to reduce the risks of delays and interface issues. (2) Prior to the construction coordination meeting, the owner should invite relevant units and personnels to confirm the designated locations for contractor waste disposal and material stacking, as well as explain the relevant regulations for the submission of valuable materials, in order to reduce contractor transportation time and handling issues. (3) After the completion of the repair project, the as-built drawings should be archived. When planning for future projects, to verify the relevant original drawings and to conduct on-site inspections as well as supplemented by equipment verification if necessary, are suggested. The contractor should submit relevant personnel licenses, work experience, and inspection records of concealed parts to the owner before construction in order to reduce issues caused by non-professionals and provide reference materials for subsequent repair projects. (4) Repair projects generally arise after a certain period of time since the original building was put into use, and they are carried out to meet the expectations of the user units. Therefore, during the assessment phase, it is necessary for the design unit to communicate and discuss extensively with the user units to clarify requirements. After confirming the requirements, they should be documented for reference. During the design phase, double-check the drawings for accuracy or omissions to reduce inconsistencies in requirements and minimize design changes. Hopefully, the research findings can be referenced by the user units, design supervisors, and contractors of repair projects, thereby improving the quality of schedule control in repair projects and effectively reducing project delays. | en_US |