型钢混凝土及预应力型钢混凝土梁试验研究

预应力型钢混凝土梁(PSRCB)是在普通型钢混凝土梁(SRCB)的基础上采用预应力技术的一种新型组合结构,利用型钢混凝土技术提高混凝土结构的承载能力,利用预应力技术改善型钢混凝土结构在正常使用极限状态下的性能,从而发挥更好的结构综合效能.鉴于目前国内外对PSRCB进行的试验研究较少,本文对8根PSRCB和6根对比SRCB进行了全过程载荷试验.试验研究表明,与SRCB相比,PSRCB具有如下特点:较好的抗裂性能;同等M/Mu下,裂缝向上延伸高度和受拉钢筋应力大大减小从而使最大裂缝的宽度变小,裂缝闭合性能较好;承受外荷载前,存在反向挠度对正常使用性能有利,随着预应力度的加大极限挠度减小,且变形恢复性能较好;同等截面条件下,可以实现更高的正截面承载力.

Experimental Study on Steel Reinforce Concrete Beam and Prestressed Steel Reinforced Concrete Beam

PSRC beam is a new type prestressed composite beam which uses prestressing technology in SRC beam.The H-section steel inside increases flexural strength and prestressing technique improves its working performance.6 SRC beams and 8 PSRC beams have been done and the following aspects have been taken into account: compressive strength of concrete;rebar ratio and cover thickness;H-section steel cover thickness and degree of prestressing.The experimental results indicate that PSRCB have the following property by contrast with SRCB: better resistance to crack;lower strain of tensile rebar and smaller crack width;better crack closing performance;smaller deflection and displacement restoring capacity;higher ultimate bearing capacity.