多孔玄武岩粗骨料HPC的制备和收缩性能研究
Preparation and Shrinkage Performance of Porous Basalt Coarse Aggregate HPC
孙婧 1洪俊哲 2王珅 2常璞 2贾小静 2刘宏波2
作者信息
- 1. 河北建筑工程学院土木工程学院,张家口 075000;河北土木工程诊断、重建与抗灾重点实验室,张家口 075000
- 2. 河北建筑工程学院土木工程学院,张家口 075000
- 折叠
摘要
为解决多孔玄武岩粗骨料吸水率大、早期吸水快给高性能混凝土(HPC)制备带来的黏度大、拌合难、耐久性差等问题,引入附加用水量预湿骨料,研究了不同附加用水量对多孔玄武岩混凝土工作性能、力学性能、收缩性能、孔结构和微观形貌的影响,并与普通碎石混凝土性能作对比.结果表明:当附加用水量取4％或6％(以多孔玄武岩粗骨料的质量分数计)时,可制得C60抗压强度等级、工作性优良和低收缩的HPC.与普通碎石混凝土相比,预吸水的多孔玄武岩能显著降低HPC的自收缩,而对抗压强度影响不大;自收缩率随附加用水量的增加而降低,其变化发展分为快速增长、短暂膨胀、缓慢增长、趋于稳定四个阶段;含水玄武岩有内养护作用,在水化后期可细化孔结构,提高界面过渡区的密实性,减少HPC的开裂风险.
Abstract
In order to solve the problems of high viscosity,difficult mixing and poor durability of high performance concrete(HPC)caused by large water absorption rate and fast early water absorption of porous basalt coarse aggregate,additional water consumption was introduced to prepare pre-wetted aggregate before preparation.The effects of different additional water consumption on workability,mechanical performance,shrinkage performance,pore structure and microstructure of porous basalt concrete were studied.And the performance of porous basalt concrete was compared with that of ordinary crushed stone concrete.The results show that when the additional water consumption is 4％or 6％(calculated by mass fraction of porous basalt coarse aggregate),the HPC with C60 compressive strength grade,excellent workability and low shrinkage can be obtained.Compared with ordinary gravel concrete,pre-absorbed porous basalt can significantly reduce the autogenous shrinkage of HPC,and has little effect on compressive strength.The self-shrinkage rate decreases with the increase of additional water consumption,and its development is divided into four stages of rapid growth,short-term expansion,slow growth and stabilization.The water-bearing basalt has internal curing effect,which can refine the pore structure in the later stage of hydration,improve the compactness of the interfacial transition zone and reduce the cracking risk of HPC.
关键词
多孔玄武岩/HPC/收缩性能/孔结构/界面过渡区Key words
porous basalt/HPC/shrinkage performance/pore structure/interface transition zone引用本文复制引用
基金项目
河北省科技厅重点研发计划(20373802D)
河北省建设科技研究计划(2020-266)
河北省高校2022年基本科研业务费项目(2022CXTD01)
河北建筑工程学院研究生创新基金(XY2023035)
出版年
2024
国家科技期刊平台
NSTL
维普
万方数据