Managing concrete crack information through correction of the slab rebar arrangement based on Six Sigma

• Published in: KSCE journal of civil engineering Vol. 19; no. 7; pp. 1973 - 1981
• Main Authors: Eom, S. J., Jang, Won-Suk, Kim, Sang-chul
• Format: Journal Article
• Language: English
• Published: Seoul Korean Society of Civil Engineers 01.11.2015; Springer Nature B.V; 대한토목학회
• Subjects: Civil Engineering; Construction; Construction industry; Construction Management; Defects; Deviation; Engineering; Geotechnical Engineering & Applied Earth Sciences; Industrial Pollution Prevention; Principles; Quality control; Rebar; Six Sigma; 토목공학; covering depth; six sigma; rebar arrangement; rebar spacing; concrete crack
• ISSN: 1226-7988; 1976-3808
• DOI: 10.1007/s12205-015-0278-3

The Six Sigma principle is a set of techniques and tools for measuring the defect rate in a process. It seeks to improve the quality of process outputs by identifying and removing the causes of defects. It has a significant advantage in quality improvement and can evaluate the process capability and statistical quality control. Since it was introduced in the 1980s, it has spread to almost all industries. However, it was not effective in the construction industry, where it was completed onsite by personnel rather than in a factory by machines. Therefore, few studies have been conducted on its application in the construction industry. This study was conducted to control slab cracks in the framework in the construction stage through the application of the Six Sigma principle. Using the Define-Measure-Analyze-Improve-Control (DMAIC) methodology, the study was conducted after the “Critical To Quality” (CTQ) was defined to improve the accuracy of the slab rebar arrangement. The Big Ys from the CTQ were defined as the covering depth deviation (Y1) and the rebar spacing deviation (Y2). In four sample projects, five potential causes of the Y1 and Y2 were identified in four areas, and corresponding improvement and validation methods were proposed. Then six solutions were abstracted, and their corresponding manual, checklist, and slab control plan were prepared. The validation was carried out through two projects, both with high achievements, with the application of the Six Sigma principle. The authors believe this paper offers valuable insights on how the Six Sigma principle can be effectively applied to the construction industry.