2022 年 68A 巻 p. 722-731
The present study aims to numerically investigate the essential factors affecting stepwise construction stress in RC deck slabs of multiple span steel box girder bridges utilizing layered model. According to the results of the numerical simulation on a successful case of cracking mitigation in the RC deck slab of 4-span Fudaigawa Ohashi bridge, it was revealed that time interval between concrete placing steps, concrete volume of interior support lots and placing sequence were main driving forces altering the generated tensile stress. Consequently, an effective stepwise construction strategy was proposed for mitigating maximum experienced tensile stress and residual tensile stress in concrete lots due to stepwise construction. The effectiveness of the proposed strategy was verified in back analysis of 7-span Shinkesen Ohashi bridge.