横梁加筋方式以控制双T板端部裂缝的技术研究
Technical Research on Beam Reinforcement Method to Control End Cracks of Double T-Plates

本文以上海地区李尔亚洲总部大楼项目中的预制混凝土构件双T板为研究对象，分析了项目所使用的预应力双T板，考虑其为满足常规跨度而突破了设计宽度，导致双T板端部出现裂缝的原因，通过对端部横梁加筋与端部顶板斜筋及内腋角位置加筋，具体为450 mm肋梁高度的双T板端部横梁(横梁100 mm高)加筋(φ^R6@100)；600 mm或800 mm肋梁高度的双T板端部横梁(横梁150 mm高)加筋，并针对加筋后的试件进行标准试验分析。结果显示，加固后试件的屈服承载力、峰值承载力、屈服跨中挠度、峰值跨中挠度都有提高，分别约为1.56倍、1.47倍、1.98倍、1.46倍。理论结合实际，提出了预应力双T板裂缝控制的具体加筋措施，为以后双T板施工积累了经验。
Taking the prefabricated concrete component double T-plates in the Li’er Asia headquarters building project in Shanghai as the research object, this paper analyzes the prestressed double T-plates used in the project. Considering the reason why it broke through the design width to meet the conventional span, resulting in cracks at the end of the double T-plates, the end crossbeam is reinforced, and the top plate diagonal reinforcement and inner armpit corner position are reinforced. Specifically, the end crossbeam (100 mm high) of the double T-plates with a 450 mm rib beam height is reinforced (φ^R6@100); a double T-plate end beam with a height of 600 mm or 800 mm ribs (150 mm high beam) was reinforced, and standard test analysis was conducted on the reinforced specimens. The results showed that the yield bearing capacity, peak bearing capacity, yield mid-span deflection, and peak mid-span deflection of the reinforced specimens all increased, with values of approximately 1.56 times, 1.47 times, 1.98 times, and 1.46 times, respectively. Combining theory with practice, specific reinforcement measures for crack control in prestressed double T-plates have been proposed, accumulating experience for future double T-plates construction.