钢纤维再生混凝土梁受弯承载力试验分析

Experimental analysis on flexural capacity of steel fiber reinforced recycled concrete beams

为了研究钢纤维再生混凝土受弯构件的力学性能,设计制作了5根再生混凝土简支梁,包括1根普通再生混凝土梁和4根不同掺量的钢纤维再生混凝土梁。对试验梁进行两点加载直至破坏,获得了试验梁开裂荷载、极限荷载、挠度等相关试验数据。基于试验数据,分析了钢纤维再生混凝土梁的力学性能。分析结果表明:钢纤维再生混凝土梁在受力过程中基本符合平截面假定;其荷载-挠度曲线与普通混凝土梁相近;且钢纤维的掺入可以较好地抑制裂缝的发展,提高钢纤维再生混凝土梁的延性。利用GB 50010—2010《混凝土结构设计规范》与CECS 28:2004《纤维混凝土结构技术规程》中相关规定对试验梁承载力进行验算,验算结果与试验结果有一定差距。为此,在试验数据基础上,以GB 50010—2010《混凝土结构设计规范》与CECS 28:2004《纤维混凝土结构技术规程》中的相关计算式为依据,提出了钢纤维再生混凝土梁开裂荷载计算式和极限承载力计算式。验算结果与实测值吻合较好。

In order to study the mechanical properties of steel fiber reinforced recycled concrete flexural members,5 recycled concrete simply supported beams were made,including 1 ordinary recycled concrete simply supported beam and 4 different content of steel fiber reinforced recycled concrete simply supported beams,the relevant test data such as cracking load,ultimate load,deflection of the test beams were obtained by the two-point loading method.Based on the test data,the mechanical properties of steel fiber recycled concrete beams were analyzed.The results show that steel fiber recycled concrete beams basically conform to the flat section assumption during the loading process.The load-deflection curves of steel fiber recycled concrete beams are similar to those of ordinary concrete beams,and the steel fiber can effectively inhibit the development of cracks and improve the ductility of steel fiber recycled concrete beams.Using the relevant provisions of GB 50010—2010“Design Code of Concrete Structure”and CECS 28:2004“Technical Specification of Fiber Reinforced Concrete Structure”,the bearing capacity of the beam is checked and there is a certain gap between the checking result and the test result.For this reason.On the basis of the test data,based on the relevant calculation formula in GB 50010—2010“Design Code of Concrete Structure”and CECS 28:2004“Technical Specification of Fiber Reinforced Concrete Structure”,the calculation formula for the cracking load and the ultimate bearing load of the steel fiber recycled concrete beams are proposed,and the checking result agrees well with the measured value.