Performance improvement of precast products and adoption assessment of construction methods

• Main Authors: Kuo, Chiang-Pin, 郭江屏
• Other Authors: Chao, Li-Chung
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/v2z9n8

博士 === 國立高雄科技大學 === 工學院工程科技博士班 === 107 === Taguchi method was utilized to develop the ultimate loads of concrete pipes in three-edge bearing tests and to maximize the corrosion resistance of aluminate-cement mortars. Design factors namely, wire diameter, wire winding pitch and water/cement ratio of concrete were used in designing pipes with inside diameters of 400mm and 600mm with goals of maximization of crushing load, ultimate load and minimization of crack width in the tests. Totally six optimal designs were obtained and verified and the most effective factors on the crushing load, ultimate load and crack width were found inconsistent for pipes with different diameters. Design factors namely, water/ cementitious material ratio, mix water content, ground blast furnace slag/cementitious material ratio and fly ash/cementitious material ratio were used in designing corrosion resistant aluminate- cement mortars with goals of maximization of compressive strength, electricity resistance and minimization of water absorption rate of the mortars. Two optimal designs were obtained and verified and the most effective factors on compressive strength, electricity resistance and water absorption rate were found blast furnace slag/cementitious material ratio, water/cementitious material ratio and fly ash/ cementitious material ratio, respectively. An aluminate-cement mortar raised its corrosion resistance when it was incorporated with blast furnace slag and fly ash was also found in the study. In addition, Analytic hierarchy process (AHP) and Analytic network process (ANP) were used to evaluate construction methods of pile foundations, retaining walls and box culvert works, in considering the project cost, construction period, project quality, constructability, environmental issues and site geology. The results obtained from AHP did not differ from those from ANP and the full casing pile method, precast sheet pile and precast box culvert were discovered as preferences, respectively. This study provides an approach for improving the quality of precast products and demonstrates models for evaluating preferred construction methods. With high quality precast products and proper evaluations, the willingness of adopting precast construction methods should rise.