【作者】 陈森；

【导师】 梁文彦； 付章建；

【作者基本信息】 哈尔滨工程大学 ， 建筑与土木工程（专业学位）， 2016， 硕士

【摘要】 钢纤维混凝土是一种性能优良且应用广泛的复合材料,其动态力学性质的研究对于充分利用材料的强度,降低工程造价和提高设计水平具有重要的意义。但是,目前广泛使用的混凝土强度准则只适用于准静态荷载作用的条件下,没有考虑应变率对混凝土强度的影响。尤其是抗拉强度作为混凝土的一个重要力学性质,人们对其在多轴动态荷载下的研究较少。本文首先对钢纤维混凝土的静态力学性能和静态强度准则进行了综述,其次介绍了混凝土的动态试验研究进展和成果。针对高应变率下的混凝土强度准则,本文根据混凝土的经典静态强度准则提出了一种修正模型。其中以Ottosen准则和Willam-Warnke准则为例分别推导出了其在高应变率下的利用动态增强因子DIF修正的强度准则。最后,利用巴西圆盘试样实现了不同钢纤维掺量的混凝土准静态和动态二轴拉-压试验,并推导出巴西圆盘劈拉强度与八面体应力的关系。利用球型试样实现了不同钢纤维掺量的混凝土准静态和动态三轴压-拉-拉试验,并且根据实验结果讨论了钢纤维和应变率对混凝土劈拉强度的影响。更多还原

【Abstract】 Steel fiber reinforced concrete is a widely used composite material with excellent performance, the research of its dynamic mechanical properties are very important to make full use of its strength, improve the design level and reduce the project cost. However, at present most of the concrete strength criterions only applies to static loads, without considering the effect of strain rate. Especially, tensile strength as an important mechanical properties of concrete, the study of its properties under multiaxial dynamic loads is very lack.Firstly, this article reviewed the static mechanical properties and static strength criteria of steel fiber reinforced concrete, then give an introduction of dynamic experimental research progress and achievements of concrete. For the strength criterion of concrete under high strain rate, this paper presents a modified model based on the classic static strength criterion of concrete. Take the Ottosen criterion and Willam-Warnke criterion for example,this article deduced theirs correction strength criterion under high strain rate, which modified by dynamic increase factor.Finally,Use the Brazilian disc specimen to realize concrete,which has different content of steel fiber, quasi-static and dynamic biaxial tension - compression test, and deduced the relationship between Brazilian disc splitting tensile strength and octahedral stress. Use the spherical specimen to realize concrete, which has different content of steel fiber,triaxial compression - tension - tension test, and the influence of strain rate and different steel fiber volume fractions on splitting tensile strength of concrete was discussed by the results.更多还原