受压区跨中加强塑钢纤维轻骨料混凝土梁受弯性能试验研究  

Experimental study on flexural performance of reinforced plastic steel fiber reinforced lightweight aggregate concrete beams in compression zone

作　　者：牛建刚 许文明 梁剑 NIU Jiangang;XU Wenming;LIANG Jian(School of Civil Engineering,Inner Mongolia University of Science and Technology,014000 Baotou,China;School of Civil Engineering,Chongqing University,401331 Chongqing,China;School of Civil Engineering,Guangxi University,530004 Nanning,China)

机构地区：[1]内蒙古科技大学土木工程学院,包头014000 [2]重庆大学土木工程学院,重庆401331 [3]广西大学土木工程学院,南宁530004

出　　处：《应用力学学报》2023年第4期917-925,共9页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金资助项目(No.51368042);内蒙古自治区青年科技英才支持计划资助项目(No.NJYT-18-A06)。

摘　　要：考虑到塑钢纤维轻骨料混凝土梁受压区跨中的力学性能是梁整体受弯力学性能提高的关键因素,以跨中局部受压区使用钢纤维加强、螺旋箍筋和矩形箍筋加强3种加强方式为基本参数,完成了6根受压区加强塑钢纤维轻骨料混凝土梁受弯加载试验研究。讨论了加强方式、纵筋配筋率和加强区混凝土强度对塑钢纤维轻骨料混凝土加强梁受弯力学性能产生的影响。结果得出:塑钢纤维对轻骨料混凝土梁有增韧阻裂、延缓裂缝发展的作用,且经受压区跨中加强后的塑钢纤维轻骨料混凝土梁超筋破坏现象得到明显改善;受压区跨中使用螺旋箍筋加强试件的承载力和延性最好,受压区跨中使用钢纤维加强试件的混凝土极限压应变最大,受压区跨中使用矩形箍筋加强混凝土试件延性最差;增大纵筋配筋率,受压区跨中使用钢纤维加强试件的承载力有明显提高,但延性降低,增大加强区混凝土强度,受压区跨中使用钢纤维加强试件承载力有一定程度提高,而延性变化不大。Considering that the mechanical properties of the compression zone of plastic steel fiber reinforced lightweight aggregate concrete beams in the mid span are the key factor in improving the overall bending mechanical properties of the beams,six compression zone reinforced plastic steel fiber reinforced lightweight aggregate concrete beams were tested under bending loading using three strengthening methods:steel fiber reinforcement,spiral stirrups,and rectangular stirrups as the basic parameters for the local compression zone in the mid span.The effects of reinforcement methods,longitudinal reinforcement ratio,and concrete strength in the reinforcement zone on the flexural mechanical properties of plastic steel fiber reinforced lightweight aggregate concrete reinforced beams were discussed.The results show that plastic steel fibers have the effect of toughening,cracking resistance,and delaying crack development on lightweight aggregate concrete beams,and the phenomenon of super-reinforced failure of plastic steel fiber lightweight aggregate concrete beams has been significantly improved after mid span strengthening in the compression zone.The bearing capacity and ductility of the specimens reinforced with spiral stirrups in the mid span of the compression zone are the best,while the ultimate compressive strain of the concrete reinforced with steel fibers in the mid span of the compression zone is the highest,while the ductility of the concrete specimens reinforced with rectangular stirrups in the mid span of the compression zone is the worst.By increasing the longitudinal reinforcement ratio,the bearing capacity of the specimens strengthened with steel fibers in the mid span of the compression zone has been significantly improved,but the ductility has decreased.By increasing the concrete strength in the strengthened zone,the bearing capacity of the specimens strengthened with steel fibers in the mid span of the compression zone has been improved to a certain extent,with little change in ductility.

关 键 词：塑钢纤维 轻骨料混凝土 超筋梁 抗弯性能 延性 

分 类 号：TU528.2[建筑科学—建筑技术科学]