骨料尺寸对混凝土层裂强度的影响  

On the Effect of Aggregate Size on Concrete Spalling Strength

作　　者：张磊[1] 吴建华[1] 高伟亮[1] 陈力[1] 孙艳[2] 高笑娟[2] 

机构地区：[1]总参工程兵科研三所,河南洛阳471023 [2]河南科技大学规划与建筑工程学院,河南洛阳471003

出　　处：《实验力学》2011年第6期730-734,共5页Journal of Experimental Mechanics

基　　金：国家自然科学基金项目(10802098)

摘　　要：作为混凝土材料的主要组成部分,骨料对混凝土力学性能具有重要影响。但骨料尺寸对混凝土层裂强度的影响仍缺少研究。本文利用大直径Hopkinson杆对混凝土细长杆件进行层裂实验,通过放置在试件后方吸收杆上的波形测量混凝土层裂强度。对两种不同尺寸骨料的混凝土进行了不同冲击速度下的层裂实验研究。实验结果表明,在相同加载条件下,骨料尺寸越大混凝土层裂强度越低,其主要原因是大尺寸骨料混凝土的界面过渡区强度更低;混凝土层裂强度具有率效应,即加载率越高其层裂强度也越高。但当加载波超过一定阈值时,由于压缩损伤演化和积累,层裂强度会降低。As a major ingredient of concrete, aggregate has an important effect on concrete mechanical behaviors, but up to now, less work was addressed to the influence of aggregate size on concrete spalling strength. Slender concrete rod spalling experiment was carried out by using a large diameter Hopkinson pressure bar equipment, in which stress pulse produced in buffer bar mounted behind the concrete rod was measured to determine spalling strength. Experiment is focused on the influence of two kinds of concrete with different aggregate sizes and subjected to different impact velocities on the concrete spalling. Results indicate that concrete containing larger size aggregates has lower spalling strength under the same loading condition. This can be attributed to the weakened strength in the larger aggregate interracial transition zone. Results also reveal that spalling strength of concrete has a rate effect, namely, the higher loading rate is, the higher spalling strength is. However, when loading wave exceeds a threshold, the spalling strength decreases due to the evolution and accumulation of compressive damage in concrete.

关 键 词：HOPKINSON杆 混凝土 骨料尺寸 层裂强度 过渡区 

分 类 号：O347.4[理学—固体力学]