海水海砂高性能海工混凝土力学及早期工作性研究  

Research on the preparation and durability of brine marine sand high performence concrete

作　　者：李田雨[1] 张玉梅[1] 刘小艳[1] 李伟华 陈靓 LI Tianyu;ZHANG Yumei;LIU Xiaoyan;LIWeihua;CHEN Liang(College of Mechanics and Materials,Hohai University,Nanjing 210098,China;School of Chemical Engineering and Technology,Sun Yat-Sen University,Zhuhai 519000,China)

机构地区：[1]河海大学力学与材料学院,江苏南京210098 [2]中山大学化学工程与技术学院,广东珠海519000

出　　处：《混凝土》2019年第11期1-5,共5页Concrete

基　　金：河海大学中央高校基本科研业务费项目（2017B05614）

摘　　要：使用海水、海砂代替传统的河水河砂制备混凝土,制备出一种早强低自收缩、高流动度低黏度的海水海砂高性能混凝土。相比河水河砂混凝土,海水海砂的使用可以使水化更充分,加速水化使混凝土具备较高的早期强度;海水海砂混凝土自收缩量降低了15%,收缩结束时间提前,减少了混凝土裂缝的产生;海水海砂混凝土黏度值为7590 MPa·s,流动度为182 mm,降低了混凝土的黏度增加了流动度,使混凝土更易于泵送,降低了施工难度。28 d抗压抗折强度比使用河水河砂制备的混凝土分别降低了8.6%和25.4%;热水养护可以提高海水海砂混凝土的力学性能,其抗压、抗折强度分别提高了22.8%和23.1%。海水海砂混凝土孔隙液pH与河水河砂混凝土基本相同;使用热水养护会降低混凝土的孔隙液pH,最小值12.01>11.50(钢筋钝化膜破坏的临界值)。研究了海水海砂制备高性能混凝土的力学与早期工作性能,为海水海砂混凝土的推广应用奠定了理论基础。Instead of traditional river sand,seawater sand and sea sand are used to prepare concrete.Compared with river sand concrete,the use of sea sand can make the hydration more sufficient and accelerate the hydration so that the concrete has higher early strength.The self-shrinkage of sea sand concrete decreased by 15%,and the end time of shrinkage was advanced,which reduced the generation of concrete crack.The viscosity value of sea sand concrete is 7590 MPa·s and the fluidity is 182 mm,which reduces the viscosity of concrete and increases the fluidity,makes concrete easier to pump and reduces the difficulty of construction.The strength of concrete made by 28 d was reduced by 8.6%and 25.4%,respectively,compared with that made by river sand.Hot water curing can improve the mechanical properties of marine sand concrete,and its compressive and flexural strength increased by 22.8%and 23.1%respectively.The porosity pH of sea sand concrete is basically the same as river sand concrete.Using hot water for curing will reduce the pH of the pore fluid of concrete,with a minimum value of 12.01>11.50(critical value of the destruction of steel passivating film).The mechanics and early working performance of high performance concrete prepared from marine sand are studied,which lays a theoretical foundation for the popularization and application of marine sand concrete.

关 键 词：海工混凝土 海砂 水化热 自收缩 黏度 

分 类 号：TU528.01[建筑科学—建筑技术科学]