超高韧性水泥基复合材料动态压缩力学性能试验研究

发布时间：2018-03-04 20:41

本文选题：UHTCC　切入点：应变率敏感性　出处：《浙江海洋大学》2017年硕士论文　论文类型：学位论文

【摘要】：作为能够克服混凝土韧性差、裂缝宽度难以控制等缺点的一种新型高性能建筑材料,超高韧性水泥基复合材料(ultra-high toughness cementitious composites,UHTCC)的研究越来越热门。目前对UHTCC的性能的研究多集中于准静态下,在动态力学性能的方面则要少得多。但许多工程结构有时要遭受动态荷载的作用,在动态荷载作用下UHTCC材料可展示怎样的性能将成为其在这些结构中的应用是否能取得预期良好效果的关键。为了能更加全面的掌握UHTCC性能,为其工程应用提供必要的科学依据。本文对UHTCC动态轴压性能开展了一系列的研究,完成了以下工作:1.研究了低应变率下纤维掺量和应变率对UHTCC动态抗压强度、峰值应变、弹性模量和泊松比的影响。结果发现UHTCC是一种应变率敏感性材料,UHTCC的抗压强度随应变率的增加而增加,纤维掺量对UHTCC抗压强度应变率敏感性有一定影响,峰值应变和泊松比无应变率敏感性。弹性模量随应变率的增加有上升的趋势;2.研究了低应变率下湿度、纤维掺量、应变率三种因素对UHTCC动态抗压性能的影响。结果发现湿度、应变率、纤维掺量均对UHTCC动态抗压力学性能有影响,且是相关的。其中湿度对UHTCC和基体动态抗压强度和峰值应变的影响是削弱作用,湿度对UHTCC及基体泊松比影响规律不明显,而对弹性模量有一定的增强作用;3.研究了中等应变率下纤维掺量、湿度和应变率三种因素对UHTCC动态轴向压缩的力学性能的影响。中等应变率下饱和湿度和干燥UHTCC均具有应变率敏感性,饱和湿度和干燥UHTCC抗压强度随应变率的增加而增加,两种状态下UHTCC均存在一种最优纤维掺量使得UHTCC抗压强度最大。饱和湿度和干燥状态UHTCC峰值应变随应变率的增加而减小,湿度对它的影响是增强作用;通过实验我们发现UHTCC是应变率敏感性材料,应变率、纤维掺量和湿度对UHTCC的动态抗压性能都有一定的影响。本文对UHTCC的研究将有利于把UHTCC推广应用于防波堤、大坝等水利设施,还能为水利设施的结构设计的性能参数提供参考,从而可以为推广UHTCC的应用发展提供帮助。
[Abstract]:As to overcome the poor toughness of concrete, a new type of high performance building materials difficult to control the defects of crack width, ultra high toughness cementitious composite (ultra-high toughness cementitious composites, UHTCC) research is more and more popular. The current research on the performance of UHTCC mainly focus on the static and dynamic mechanical properties in the aspects of much less. But many engineering structures sometimes suffer from dynamic load, can show how the performance of UHTCC materials under dynamic load will become the key whether its application in these structures can achieve expected good results. In order to be more comprehensive grasp of the performance of UHTCC, to provide the necessary scientific basis for the project the application of UHTCC in this paper. The dynamic axial compression performance to carry out a series of studies, completed the following work: 1. research on the low strain rate of fiber content and strain rate of UHTCC The dynamic compressive strength, peak strain, elastic modulus and Poisson's ratio. The results showed that UHTCC is a strain rate sensitive material, increase the compressive strength of UHTCC decreases as the strain rate increases, fiber content has a certain effect on the compressive strength of UHTCC strain rate sensitivity, peak strain and Poisson's ratio of non elastic strain rate sensitivity. The modulus decreases with the increase of strain rate has a rising trend; 2. on the low strain rate humidity, fiber content, influence on the compressive properties of UHTCC dynamic strain rate of three factors. The results show that the humidity, strain rate, fiber content all have effects on the dynamic compressive mechanical properties of UHTCC, and the effect is relevant. Humidity on the UHTCC matrix and the dynamic compressive strength and peak strain is weakened, humidity on UHTCC and matrix Poisson's ratio influence is not obvious, but there are certain enhancement effect on the elastic modulus of medium strain rate; 3. The amount of doped fiber, humidity and strain rate of three kinds of influencing factors on dynamic mechanical properties of UHTCC axial compression. With strain rate sensitivity under saturated humidity and dry UHTCC medium strain rate, increase the saturated humidity and dry UHTCC compressive strength decreases as the strain rate increases, an optimal fiber content makes the UHTCC maximum compressive strength there are two kinds of state UHTCC. Increasing saturated humidity and dry state UHTCC peak strain and decreases with strain rate, the influence of humidity on it is enhanced; through the experiment we found that UHTCC is a strain rate sensitive material, strain rate, are affected by dynamic compressive properties of fiber content and humidity on UHTCC. The study of UHTCC will be conducive to the promotion and application of UHTCC to the breakwater, dams and other water conservancy facilities, but also provide reference for the performance parameters of structure design of water conservancy facilities, which can promote UH The application and development of TCC help.

【学位授予单位】：浙江海洋大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU599

【相似文献】