西安建筑科技大学学报(自然科学版)

为研究早龄期预制叠合剪力墙的收缩变形特性,制作了一片小尺寸预制叠合剪力墙试件并进行试验观测.通过对剪力墙内部自干燥和湿度扩散形成的湿度场计算,基于GL2000收缩模型,对预制叠合剪力墙收缩应变进行了计算分析,计算结果与试验结果吻合良好.比较了墙厚和外部环境湿度条件参数对预制叠合剪力墙收缩变形的影响,并对暴露在不同环境湿度条件下的早龄期预制叠合剪力墙开裂风险进行了预测.

To investigate the shrinkage behavior of precast superimposed reinforced concrete shear wall(SRCSW)at early ages, one SRCSW specimen in small size was constructed and tested. The moisture field of the specimen developed by self-desiccation and moisture diffusion was analyzed. According to the GL2000 theory, the shrinkage response was calculated and the analytical results match well with the test results. Lastly, the influence of wall thickness and the environmental humidity on the shrinkage behavior was discussed and the cracking potential of SRCSW under different environmental humidity conditions was predicted.

引言
1 收缩变形试验
2 基于湿度场的收缩变形计算
3 收缩变形参数分析与开裂风险预测
4 结论

图1 混凝土由于收缩变形不平衡引起内应力示意图<br/>Fig.1 Illustration of intrinsic strain generated by inconsistent shrinkage in concrete

图1 混凝土由于收缩变形不平衡引起内应力示意图
Fig.1 Illustration of intrinsic strain generated by inconsistent shrinkage in concrete

表1 自密实混凝土配合比及工作性能<br/>Tab.1 Mix proportion and workability of SCC

表1 自密实混凝土配合比及工作性能
Tab.1 Mix proportion and workability of SCC

表2 自密实混凝土材料参数<br/>Tab.2 Mechanical properties of SCC

表2 自密实混凝土材料参数
Tab.2 Mechanical properties of SCC

图2 应变计安装示意图<br/>Fig.2 Arragngement of strain gauges

图2 应变计安装示意图
Fig.2 Arragngement of strain gauges

图3 温度和湿度变化<br/>Fig.3 Ambient temperature and relative humidity changes

图3 温度和湿度变化
Fig.3 Ambient temperature and relative humidity changes

图4 预制层测点收缩应变变化<br/>Fig.4 Time development of shrinkage at the prefabricate layer

图4 预制层测点收缩应变变化
Fig.4 Time development of shrinkage at the prefabricate layer

图5 夹心层测点收缩应变变化<br/>Fig.5 Time development of shrinkage at the interal layer

图5 夹心层测点收缩应变变化
Fig.5 Time development of shrinkage at the interal layer

图6 早龄期混凝土内部湿度变化<br/>Fig.6 Variation of relative humidity in concrete at early ages

图6 早龄期混凝土内部湿度变化
Fig.6 Variation of relative humidity in concrete at early ages

图7 叠合剪力墙湿度场模拟示意图<br/>Fig.7 Illustration of moisture transformation in SRCSW

图7 叠合剪力墙湿度场模拟示意图
Fig.7 Illustration of moisture transformation in SRCSW

表3 湿度场计算模型参数<br/>Tab.3 Input parameters for moisture calculation

表3 湿度场计算模型参数
Tab.3 Input parameters for moisture calculation

图8 预制叠合剪力墙湿度场模拟结果<br/>Fig.8 Simulation results of moisture diffusion in SRCSW

图8 预制叠合剪力墙湿度场模拟结果
Fig.8 Simulation results of moisture diffusion in SRCSW

图9 试验结果与计算结果的比较<br/>Fig.9 Comparison of test results with calculated results

图9 试验结果与计算结果的比较
Fig.9 Comparison of test results with calculated results

图10 墙厚参数对湿度和收缩应变的影响<br/>Fig.10 Effect of the thickness of shear wall on the moisture diffusion and shrinkage strain

图10 墙厚参数对湿度和收缩应变的影响
Fig.10 Effect of the thickness of shear wall on the moisture diffusion and shrinkage strain

图11 环境湿度参数对湿度和收缩应变的影响<br/>Fig.11 Effect of the environmental humidity on the moisture diffusion and shrinkage strain

图11 环境湿度参数对湿度和收缩应变的影响
Fig.11 Effect of the environmental humidity on the moisture diffusion and shrinkage strain

图12 开裂风险预测<br/>Fig.12 Prediction of cracking risk

图12 开裂风险预测
Fig.12 Prediction of cracking risk

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备注

引言

1 收缩变形试验

2 基于湿度场的收缩变形计算

3 收缩变形参数分析与开裂风险预测

4 结论

期刊信息