C80早龄期钢筋混凝土梁受弯性能试验研究  

EXPERIMENTAL STUDY ON BENDING BEHAVIOR OF C80 CONCRETE BEAMS AT EARLY AGE

作　　者：王冬雁[1] 吴岳刚 杨振坤[2] 王梦梦[2] 袁泉[2] 廖娟[1] 韦永斌[1] 

机构地区：[1]中国建筑股份有限公司技术中心,北京101300 [2]北京交通大学土木建筑工程学院,北京100044

出　　处：《工业建筑》2013年第12期82-87,共6页Industrial Construction

基　　金：中建科技资助项目(CSCEC-2012-Z-02);十一五科技支撑项目(2006BAJ0104)

摘　　要：通过1,3,7,28,90 d不同龄期下8根C80高强钢筋混凝土梁(RCL)试件受弯性能试验,研究钢筋混凝土梁在各种龄期下的破坏形态,量测和记录不同龄期下梁的挠度、应变、裂缝发展情况,并通过对1,3,7 d龄期梁试件早期受力(同龄期下梁破坏荷载的50%),卸荷后自然养护28 d进行抗弯性能试验,分析梁试件早期受力对后期强度及其他性能的影响,重点探究早龄期梁试件的抗弯能力和延性性能。试验结果表明:试件的开裂荷载、屈服荷载和极限荷载在早龄期(3 d前)阶段受龄期影响较大,之后影响变小,7 d后影响幅度在3%左右,1 d龄期的钢筋混凝土梁其极限弯矩可达自然养护条件下28 d龄期梁极限弯矩的90%;各种龄期下梁截面应变基本符合平截面假定;梁早期承受50%极限荷载对后期承载能力影响较小,对变形能力影响较大。Through bending experiments the paper tested the flexural behaviors of 8 C80 high strength reinforced concrete beams , whose failure modes were studied; and deflections , strains and cracks development were also measured and recorded at 1, 3, 7, 28, 90 d.In order to study the influence of the early load （50% of ultimate compressive strength ） on the long-term performance of beams , it was also carried out the tests in which beams were loaded to a level about 50%of ultimate compressive strength and then unloaded at the age of 1, 3, 7 d.After that the specimens were cured under natural conditions for 28 d and then were tested again .The two tests’ results show that the cracking load, yield load and ultimate load of specimens in the concrete early age （3 d ago） were influenced by ages greatly and were affected little after 3 d, the degree was about 3% after 7 d.The ultimate moment of C80 reinforced concrete beams of 1 d age can reach the 90%of that of 28 d.The cross-section strains at various concrete ages were agreed with those of plane section assumption .The beam carried 50%ultimate load at concrete early age which has smaller influence on deformation capacity and greater one on carrying capacity .

关 键 词：C80高强钢筋混凝土梁 早期受荷 试验研究 受弯性能 

分 类 号：TU375.1[建筑科学—结构工程]