配500MPa钢筋预应力混凝土梁受弯性能试验和分析  

Experiments and Analysis of Flexural Performance of Prestressed Concrete Beams with 500MPa Steel Bars

作　　者：周建民[1] 张帆[1] 王晓锋[2] 赵勇[1] 

机构地区：[1]同济大学土木工程学院,上海200092 [2]中国建筑科学研究院,北京100013

出　　处：《力学季刊》2012年第2期239-248,共10页Chinese Quarterly of Mechanics

基　　金：国家科技支撑计划2007BAE30B05

摘　　要：基于10根预应力混凝土梁和2根普通混凝土梁的受弯性能试验,本文对配置500MPa钢筋后张有粘结预应力混凝土梁的破坏形态、非预应力筋应力、混凝土应变、位移延性等进行了相应的研究,并对我国《混凝土结构设计规范》(GB50010-2010)[1]中的开裂弯矩、正截面承载力、挠度及裂缝宽度计算公式进行了校核。结果表明:正常配筋情况下,所配置的500MPa钢筋在承载力极限状态下都能屈服;混凝土平均应变符合平截面假定;梁的位移延性随ξp增大而减小,需限制ξp以保证延性;《混凝土结构设计规范》中开裂弯矩、正截面承载力计算公式对此类梁是适用的;但同实测值相比,挠度计算值偏小,平均裂缝宽度计算值偏大。／Based on the flexure experiment results of 10 bonded post-tensioned prestressed concrete beams and 2 concrete beams, the failure pattern, stress of the nonprestressed steel bar, concrete strain and duc- tility of post-tensioned prestressed concrete beams with 500MPa bars have been investigated. The formu- las for calculating cracking moment, flexural capacity, deflection and crack width in ＂Code for design of concrete structures＂ （GB50010-2010） are also verified. The results indicate that for beams with appropri- ate longitudinal steel ratio, 500MPa steel bars can reach their yield point under the bending limit state; the distribution of average concrete strain accords with plane section hypothesis; the value ofξp needs to be restricted to guarantee good ductility, which decreases with the development of ξp; the cracking mo- ment and flexural capacity can be calculated following GB50010-2010; but the deflection calculated value is smaller , the average crack width calculated value is on the high side compared with the observations.

关 键 词：500MPA钢筋 预应力混凝土梁 位移延性 抗弯性能 

分 类 号：TU375.4[建筑科学—结构工程]