考虑地震量级作用下橡胶纤维混凝土的受压动力性能

Compression Dynamic Behavior of Rubber Fiber Reinforced Concrete under Action of Earthquake Magnitude

为探究橡胶纤维混凝土受压动力性能,分别按0%和30%橡胶取代率、0%和0.6%聚丙烯纤维掺量配制4种配合比橡胶纤维混凝土;同时考虑8种地震量级加载应变率,应用液压伺服机对橡胶纤维混凝土开展单轴受压试验,得到不同加载工况下橡胶纤维混凝土受压破坏形态和应力-应变曲线.结果表明:掺有橡胶颗粒和聚丙烯纤维的混凝土静动力受压破坏形态完整性相对较高,橡胶颗粒作用能够有效提高混凝土的延性特征;随着加载应变率的提高,橡胶纤维混凝土峰值应力逐步增大,其中单掺聚丙烯纤维的混凝土峰值应力动力提高系数和弹性模量动力提高系数明显高于其他配合比工况,单掺橡胶颗粒的混凝土所表现出的规律则与之相反;另外,分别提出了加载应变率与橡胶纤维混凝土峰值应力动力提高系数和弹性模量动力提高系数的关系方程,并对其受力机理进行了探讨.

In order to determine the dynamic performance of rubber fiber reinforced concrete(RFRC)under compression,four kinds of rubber fiber reinforced concrete were prepared according to 0%,30%rubber substi⁃tution rate and 0%,0.6%polypropylene fiber content respectively under eight earthquake loading strain rates.According to the test results,the failure modes and stress-strain curves of rubber fiber reinforced concrete under different loading conditions are obtained.Through comparative analysis of the mechanical parameters of rubber fiber reinforced concrete under different loading conditions,the following conclusions are obtained:the integrity of rubber particle and polypropylene fiber reinforced concrete under static and dynamic pressure is relatively high,and the rubber particle can effectively improve the extension of concrete with the increase of loading strain rate,the peak stress of rubber fiber reinforced concrete increases gradually.The dynamic improvement coeffi⁃cients of peak stress and elastic modulus of concrete with polypropylene fiber are significantly higher than those of other mixing conditions,whereas the situation for concrete with rubber particles is just the opposite.At the same time,the relationship equations between the loading strain rate and the dynamic improvement coefficients of peak stress and elastic modulus are put forward respectively,and the stress mechanism is discussed.