低胶材泵送机制砂混凝土的应用研究  

Study on Engineering Application of Low Binder Pumped Machine-made Sand Concrete

作　　者：王涛 刘兴荣[2,3] 杜志芹 温金保[2,3] 季海 

机构地区：[1]重庆市水利电力建筑勘测设计研究院有限公司,重庆401120 [2]南京水利科学研究院,江苏南京210029 [3]南京瑞迪高新技术有限公司,江苏南京210024

出　　处：《混凝土世界》2023年第4期43-46,共4页China Concrete

基　　金：中央级公益性科研院所基本科研业务基金项目(Y420010)。

摘　　要：为满足黄沙洞水库埋石混凝土重力坝的施工技术要求,开展了低胶材泵送机制砂混凝土性能试验研究。结果表明:采用保坍型聚羧酸系高性能减水剂可明显改善低胶材泵送机制砂混凝土拌合物的和易性与可泵性等施工性能,C15和C20混凝土的坍落度经时损失分别为5.6%和0%,含气量经时损失分别为15.6%和9.1%,泌水率分别为0.2%和0%;硬化混凝土的强度与耐久性满足埋石混凝土重力坝施工技术要求,C15与C20混凝土的28d抗压强度分别为设计强度的189%和162%,经50次冻融循环后的相对动弹性模量分别为90.5%和92.3%,抗水相对渗透性系数分别为3.48×10^(-10)cm/s和1.92×10^(-10)cm/s。In order to meet the construction technical requirements of concrete for the embedding stone concrete gravity dam of Huangshadong reservoir,the performance of pumping manufactured sand concrete with low binder was experimentally studied.The results show that the construction performance of the pumping manufactured sand concrete mixture with low binder such as the workability and pump ability can be evidently improved by using polycarboxylate superplasticizer with slump retention capability.The slump loss over time of C15 and C20 concrete is 5.6%and 0%respectively.The gas content loss over time is 15.6%and 9.1%.The bleeding rate is 0.2%and 0%.And the strength and durability of hardened concrete meet the technical requirements of the construction of the embedding stone concrete gravity dam.The 28d compressive strength of C15 and C20 concrete is 189%and 162%of the design strength.The relative dynamic elastic modulus of concrete after 50 freeze-thaw cycles is 90.5%and 92.3%.The relative permeability coefficients of water resistance arerespectively 3.48×10^(-10)cm/s and 1.92×10^(-10)cm/s。

关 键 词：埋石混凝土重力坝 保坍型聚羧酸系高性能减水剂 低胶材 可泵性 

分 类 号：TV431[水利工程—水工结构工程]