预应力超高强混凝土梁剪切延性分析  

Analysis on shear ductility of prestressed ultra-high reinforced concrete beams

作　　者：姚大立[1] 贾金青[1] 余芳[2] 

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024 [2]沈阳工业大学建筑工程学院,辽宁沈阳110178

出　　处：《哈尔滨工程大学学报》2013年第5期593-598,共6页Journal of Harbin Engineering University

基　　金：国家自然科学基金资助项目(51078059);科技部"863"计划重大交通基础设施核心技术基金资助项目(2007AA11Z133)

摘　　要：为了研究预应力超高强混凝土梁的剪切延性,对15根后张法有粘结预应力超高强混凝土简支梁进行受剪性能试验,研究了剪跨比、配箍率、混凝土强度和预应力度对试验梁的破坏形态和剪切延性的影响规律.试验结果表明:预应力超高强混凝土梁的破坏形态与预应力普通混凝土梁相似,当剪跨比为1.5≤λ≤2.5时,破坏形态均为剪压破坏;剪切延性随着剪跨比、配箍率、混凝土强度的增加而增大,随着预应力度水平提高而降低;建立了预应力超高强混凝土梁剪切延性系数的计算公式,计算结果与试验结果对比表明,剪切延性系数计算值与试验结果吻合良好,研究成果将为预应力超高强混凝土梁的设计计算与工程应用提供理论依据.In efforts to study the shear ductility of prestressed ultra-high reinforced concrete beams, 15 bonded post- tensioned prestressed ultra-high reinforced concrete simply supported beams were tested to examine shear perform- ance. The effects of shear span-depth ratio, stirrup ratio, concrete strength and degree of prestress on failure mode and shear ductility were analyzed. The test results show that failure mode of prestressed ultra - high reinforced con- crete beams were similar to prestressed ordinary reinforced concrete beams. When the shear span-depth ratio was from 1.5 to 2.5 （ 1.5 ≤λ ≤ 2.5 ）, diagonal compression failure was the main failure mode. Shear ductility increa- ses with the increase of shear span - depth ratio, stirrup ratio or concrete strength. An increase in degree of pre- stress reduces shear ductility. A formula for calculating the shear ductility coefficient of ultra - high reinforced con- crete beams was proposed. The comparison of the results between calculation and test shows that calculated value of shear ductility coefficient had a good agreement with the test data. The research achievements will provide theoreti- cal support for the design calculation and engineering application of prestressed ultra-high reinforced concrete beams.

关 键 词：预应力度 混凝土强度 剪切延性 破坏形态 

分 类 号：TU378.8[建筑科学—结构工程]