免支撑工具式桁架叠合板受弯性能试验研究与分析  

EXPERIMENTAL STUDY AND ANALYSIS ON FLEXURAL PERFORMANCE OF FREE SUPPORT TOOLTRUSS COMPOSITE SLAB

作　　者：张旭 庞祖杰 王少杰[1] 乔德浩 尹烁 李辉 张中文 ZHANG Xu;PANG Zu-jie;WANG Shao-jie;QIAO De-hao;YIN Shuo;LI Hui;ZHANG Zhong-wen(College of Water Conservancy and Civil Engineering,Shandong Agricultural University,Taian,Shandong 271018,China;Shandong Expressway Dejian Group Co.Ltd,Dezhou,Shandong 253000,China;School of Civil Engineering,Southeast University,Nanjing,Jiangsu 210096,China)

机构地区：[1]山东农业大学水利土木工程学院,山东泰安271018 [2]山东高速德建集团有限公司,山东德州253000 [3]东南大学土木工程学院,江苏南京210096

出　　处：《工程力学》2023年第8期115-125,共11页Engineering Mechanics

基　　金：国家重点研发计划政府间国际科技创新合作重点专项项目(2017YFE0195300);2021年山东省研究生教育教学改革研究项目。

摘　　要：为解决普通混凝土叠合板底板易开裂、施工需大量竖向支撑难题,研发了一种斜筋式免支撑工具式桁架叠合板。通过标准砝码加载3个跨度相同、构造措施(绑扎搭接、焊接、钢丝网片)不同的试件,明晰了构造措施对叠合板整体受弯性能无显著影响,绑扎搭接是简便、高效的措施;通过对构造措施相同跨度不同的3个试件开展试验和数值研究,探明了该类叠合板的工作机制,基于叠加原理建立了其抗弯刚度和挠度计算方法。结果表明:与实测值相比,所建理论方法与数值模型精度高,决定系数最小值分别为0.994和0.988;上部钢管与下部底板无明显协同作用,二者间桁架在跨度较小时对抗弯刚度的贡献可忽略,跨度3.4 m、4.3 m试件在开裂前、后对总体抗弯刚度的贡献占比分别是12.1%、22.0%和15.0%、26.7%;免支撑叠合板受弯性能以开裂为界具有两阶段特征,开裂后整体抗弯刚度均呈先快后慢下降趋势,钢管对叠合板抗弯刚度的贡献始终最大。研究成果为免支撑工具式桁架叠合板的应用提供了参考依据和计算方法。In order to solve the problem that the bottom plate of a common concrete composite slab is easy to crack and a lot of vertical supports are needed in its construction,a kind of oblique rib type free support tool-truss composite slab(FSTCS)was developed.Three specimens with the same span and different structural measures(overlap,welding and wire mesh)were loaded by standard weights,it was clear that the structural measures had no significant influence on the overall flexural performance of composite slabs,and overlap was a simple and efficient measure.Through the test and numerical study of three specimens with the same structural measures and different spans,the working mechanism of FSTCS was proved,and the theoretical method for calculating the flexural stiffness and deflection was established based on the superposition principle.The results show that:compared with the measured values,the theoretical method and numerical model have high precision,and the minimum determination coefficients are 0.994 and 0.988,respectively.There is no obvious synergistic effect between the upper steel tube and the bottom slab,the contribution of the truss between them to the flexural stiffness can be ignored when the span is small,and the contribution of specimens with a span of 3.4 m and of 4.3 m to the total flexural stiffness before and after cracking is 12.1%,22.0%and 15.0%,26.7%,respectively.The flexural performance of FSTCS is characterized by two stages with cracking as the boundary,after cracking,the overall flexural stiffness decreases rapidly first and then slowly,and the contribution of steel tube to flexural stiffness of composite slab is always the largest.The research results provide a reference and calculation method for the application of the FSTCS.

关 键 词：混凝土叠合板 免支撑 抗弯刚度 受弯性能 数值模拟 

分 类 号：TU375.2[建筑科学—结构工程]