混杂纤维高强混凝土井壁极限强度及破坏特征试验研究

Experimental Study on Ultimate Strength and Failure Features of Shaft Wall with Hybrid Fiber Reinforced High Strength Concrete

为验证混杂纤维高强混凝土应用于深厚表土井壁结构的可行性,通过室内模型试验研究了普通高强混凝土和混杂纤维高强混凝土井壁模型的抗压强度及破坏特征。研究结果表明:混杂纤维高强混凝土井壁模型(模型A)的抗压强度略高于普通高强混凝土井壁模型(模型B);2种模型的环向位移和轴向位移都随荷载的增大而增大,达到极限荷载时模型A的环向位移和径向位移均小于模型B,说明模型A具有更好的塑性和抗变形能力;加载过程中2种模型都经历了裂缝出现、发展、贯通等阶段,但具体表现不同,模型B破坏时保护层大面积剥落,剪切破坏特征明显,而模型A表面保护层没有大面积剥落,具有良好的整体性。

In order to verify the feasibility of hybrid fiber reinforced high strength concrete applied in the shaft wall in the thick alluvium,the ultimate compressive strength and failure characteristics of general reinforced concrete and hybrid fibers reinforced high strength concrete shaft wall were studied by the indoor model test.The study results showed that the compressive strength of hybrid fiber reinforced concrete shaft wall（Model A） was slightly higher than general reinforced concrete shaft wall（Model B）.The radial and axial displacements of two shaft wall models both increased with load increasing.When they reached the limit load,the radial and axial displacements of Model A were less than Model B.It showed that Model A had better plasticity and anti-deformability.The crack had experienced three periods on the two shaft walls during the loading process：crack appearance,development and coalescence,but the specific behavior was different.The concrete covering layer of Model B spalled in the large area,while Model A had a good integrity correspondingly and did not spall largely.