初始强度对抛石混凝土强度和结构的影响  

Study on the effect of initial strength on the strength and structure of riprap concrete

作　　者：姜正平[1] 章耀东 宋旭艳[1] 乔波[3] 郜志海[1] Jiang Zhengping;Zhang Yaodong;Song Xuyan;Qiao Bo;Gao Zhihai(College of Civil Engineering,Suzhou University of Science and Technology,Suzhou 215011,China;China Railway 24th BureauGroup Shanghai RailwayCo.,Ltd.,Shanghai 200070,China;Suzhou First Construction GroupCo.,Ltd.,Suzhou 215123,China)

机构地区：[1]苏州科技大学土木工程学院,江苏苏州215011 [2]中铁二十四局集团上海铁建工程有限公司,上海200070 [3]苏州第一建筑集团有限公司,江苏苏州215123

出　　处：《山西建筑》2022年第9期5-8,共4页Shanxi Architecture

基　　金：2020年苏州市建设科研项目(苏住建科[2020]3号)。

摘　　要：设计了坍落度180 mm~220 mm的C25,C35,C45,C55四种强度的大流动度混凝土模拟施工中使用的泵送混凝土,进而对其分别抛填不同掺量的粗骨料,测定其力学强度,同时进行试块剖面分析。结果表明,混凝土的初始强度对于最佳抛石掺量有所影响,各强度等级泵送混凝土达到其最佳抛石掺量时,混凝土强度的提升最大,并且劈裂抗拉强度的提升幅度大于抗压强度的提升,能够提高混凝土的拉压比,对改善混凝土的脆性也有一定的帮助,而且在最佳抛石掺量下,混凝土中的骨料能够成紧密堆聚结构,相互接触形成完整而有效的粗骨料骨架。This project designed C25, C35, C45 and C55 pumping concrete used in the simulation of large-flow concrete with a slump of 180 mm~220 mm. Then, the coarse aggregate with different content was dumped and filled respectively, and its mechanical strength was measured and cross-sectional parts were analyzed at the same time. The results showed that the initial strength of concrete have an impact for the optimal amount of scattering-filling coarse aggregate. When the pumped concrete of each strength grade reaches its best riprap content, the increase of concrete strength is the largest. The increase of splitting tensile strength is greater than that of compressive strength, which can improve the tensile-compression ratio of concrete and help to improve the crack resistance of concrete. Moreover, under the optimum amount of riprap, the aggregates in the concrete can form a tightly packed structure and contact each other to form a complete and effective coarse aggregate skeleton.

关 键 词：粗骨料嵌锁 抛石混凝土 混凝土开裂 堆聚结构 

分 类 号：TU528.1[建筑科学—建筑技术科学]