高强轻骨料混凝土深受弯构件受剪模型分析.PDF

第32 卷第12 期 Vol.32 No.12 工 程 力 学 2015 年 12 月 Dec. 2015 ENGINEERING MECHANICS 108 文章编号：1000-4750(2015)12-0108-09 高强轻骨料混凝土深受弯构件受剪模型分析 刘 喜，吴 涛，魏 慧，刘伯权，邢国华 (长安大学建筑工程学院，陕西，西安 710061) 摘 要：根据集中荷载作用下8 根剪跨比0.26~1.04、跨高比为2 和3 的LC40 级高强轻骨料混凝土简支深受弯构 件受剪性能试验结果，重点分析了该类混凝土深受弯构件的破坏过程与破坏形态。在试验研究的基础上，建立了 基于软化拉-压杆模型计算理论的高强轻骨料混凝土深受弯构件受剪承载力计算模型，并应用该模型完成了22 组 该类构件受剪承载力试验计算与我国GB50010-2010、ACI318-08 、CSA 和EC2 等现有规范计算结果及软化拉-压 杆模型计算结果的对比分析。分析表明：高强轻骨料混凝土深受弯构件破坏形态分为剪切破坏和弯剪破坏两种， 剪跨比 λ≤1，其受剪承载力基本由混凝土斜压杆控制，软化拉-压杆模型计算结果接近试验值，与现行规范计算 结果相当，但软化拉-压杆模型有明确的力学模型，能够合理反映深受弯构件受力机理。 关键词：轻骨料混凝土；深受弯构件；拉-压杆模型；软化效应；受剪承载力 中图分类号：TU375 文献标志码：A doi: 10.6052/j.issn.1000-4750.2014.05.0364 SHEAR STRENGTH MODEL FOR HIGH-STRENGTH LIGHTWEIGHT AGGREGATE CONCRETE DEEP FLEXURAL MEMBERS LIU Xi , WU Tao , WEI Hui , LIU Bo-quan , XING Guo-hua (School of Civil Engineering, Chang’an University, Xi’an, Shaanxi 710061, China) Abstract: According to the test results due to the action of a concentrated load for eight simply supported deep flexural members whose shear span to depth ratios and span-depth ratios are 0.26~1.04 and 2, as well as 3, respectively, and made of LC40 high-strength lightweight aggregate concrete under, the failure process and failure pattern of this kinds of deep flexural members are analyzed emphatically. The shear capacity model is established, based on softened strut-and-tie model for high-strength lightweight concrete deep flexural members. The model is used to calculate the shear strength of these 24 members, the results of which have been compared with the results accepted from the shear formulas suggested by current design codes, GB50010-2010, ACI318-