高温后型钢再生混凝土梁的受力性能及承载力计算  

Mechanical behavior and bearing capacity calculation of steel reinforced recycled concrete beam after experiencing high temperature

作　　者：陈宗平[1,2] 郑巍[1] 陈宇良[1] 

机构地区：[1]广西大学土木建筑工程学院,广西南宁530004 [2]广西大学工程防灾与结构安全教育部重点实验室,广西南宁530004

出　　处：《土木工程学报》2016年第2期49-58,共10页China Civil Engineering Journal

基　　金：国家自然科学基金(51268004;51578163);"八桂学者"建设工程专项经费;广西自然科学基金(2013GXNFSFDA019025)

摘　　要：为了研究高温后型钢再生混凝土梁的受力性能,以温度、再生粗骨料取代率和剪跨比为变化参数,设计32个试件进行高温后的静力加载试验,观察了高温后试件的外观变化和受力破坏形态,获取其荷载-挠度曲线、截面应变分布和极限承载力等重要参数,分析了各变化参数对高温后型钢再生混凝土梁力学性能的影响,并探讨了其极限承载力计算方法。研究结果表明:高温后型钢再生混凝土梁的表面颜色由灰色变暗黄、表面龟裂,受力破坏形态与常温下基本相同;随温度的升高,试件的极限承载力和刚度逐渐降低,延性变差;再生粗骨料取代率的变化对试件的承载力和刚度影响不大,但对延性有一定的影响;随着剪跨比的增大,试件的承载力和刚度降低,延性却更好。In order to study the mechanical behavior of steel reinforced recycled concrete beams after experiencing high temperature, thirty-two specimens, involving three varying parameters such as temperature, recycled coarse aggregate replacement ratio and shear span ratio, were designed for monotonic static loading test after experiencing high temperature. Based on the tests, the appearance change and mechanical failure pattern of specimens after experiencing high temperature were observed, so that those important information including load-deflection curves, cross-sectional stress distribution and ultimate bearing capacity of the specimens can be obtained. Furthermore, the effects of these varying parameters on the mechanical behavior of steel reinforced recycled concrete beam after experiencing high temperature were analyzed, and the calculation method for the ultimate bearing capacity of steel reinforced recycled concrete beam was also discussed. The research results show that the failure mode of steel reinforced recycled concrete beam after experiencing high temperature is similar to that at the normal temperature, but after experiencing high temperature the surface color of beam may change from gray to dark yellow and some cracks may appear on the beam surface. Additionally, due to the high temperature, the ultimate bearing capacity and stiffness of beam decrease, and its ductility degenerates. The replacement ratio of coarse aggregate has little effect on the bearing capacity and stiffness of the specimens, but it may significantly affect the ductility of beam. With the increase of shear span ratio, the bearing capacity and stiffness of the specimens descend, but their ductility becomes better.

关 键 词：型钢混凝土 再生混凝土 梁 高温后 受力性能 

分 类 号：TU398[建筑科学—结构工程]