摘要
为研究冻融循环与预应力共同作用下混凝土的强度损失规律,对σ_(con)/f_(ptk)=0.4、0.6、0.8三种预应力条件下的无粘结预应力梁开展25次、50次、75次快速冻融循环试验,研究了冻融循环、预应力作用以及二者共同作用对混凝土抗压强度的影响。研究结果表明,当预应力达到σ_(con)/f_(ptk)=0.8时,各冻融循环次数下的混凝土抗压强度较为接近,此时冻融循环对混凝土抗压强度的影响最小;随着冻融循环次数的增加,无预应力混凝土的抗压强度损失远大于预应力混凝土抗压强度的损失,且预应力越大的混凝土抗压强度降低越缓慢;预应力对冻融循环条件下混凝土抗压强度的衰减有抑制作用,随着预应力的增加,这种抑制作用越明显。最后,根据试验结果建立考虑冻融循环和预应力作用条件下混凝土的抗压强度损失计算模型。
In order to study the strength loss law of concrete under the combined action of freeze-thaw cycle and prestress.25 cycles,50 cycles and 75 cycles of rapid freeze-thaw cycles were carried out on unbonded prestressed beams underσ_(con)/f_(ptk)0.4,0.6 and 0.8 prestressing conditions.The law of concrete strength loss under the combined action of freeze-thaw cycle and prestress is studied.The test results show that when the prestress reachesσ_(con)/f_(ptk)0.8,the compressive strength of concrete under each freeze-thaw cycle is relatively close,and the freeze-thaw cycle has the least impact on the compressive strength of concrete.With the increase of freeze-thaw cycles,the loss of compressive strength of non prestressed concrete is much greater than that of prestressed concrete,and the greater the prestress,the slower the reduction of compressive strength.Prestress can inhibit the attenuation of concrete compressive strength under freeze-thaw cycle.With the increase of prestress,this inhibition is more obvious.Finally,according to the test results,the calculation model of compressive strength loss of concrete considering freeze-thaw cycle and prestress is established.
作者
陈瑞明
向阳开
梁路
赵毅
CHEN Ruiming;XIANG Yangkai;LIANG Lu;ZHAO Yi(Urban and Rural Planning and Construction Branch of Guiyang Vocational and Technical College,Guiyang 550081,China;School of Materials Science and Engineering,Chongqing Jiaotong University,Chongqing 400074,China;School of Water Conservancy and Construction Engineering,Shihezi University,Shihezi 832000,Xinjiang,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2022年第S01期287-291,共5页
Materials Reports
基金
山区桥梁及隧道工程国家重点实验室开放基金(CQSLBF-Y14-13)
关键词
冻融循环
预应力混凝土
抗压强度
损失规律
计算模型
freeze-thaw cycle
prestressed concrete
compressive strength
law of loss
computational model
