西安建筑科技大学学报(自然科学版)

对不同应力水平的混凝土圆柱体构件进行了冻融循环试验,在冻融循环过程中通过动态模拟法得到了冻融全过程混凝土冻胀应变的发展规律.试验结果表明:冻融循环过程中随温度降低冻胀应变不断增大,温度回升后冻胀应变随之降低.随着冻融循环次数的增加,钢筋有效应变逐渐降低,冻胀应变滞回环的上部包络线随之升高,残余应变不断增加; 随应力水平的增加,钢筋有效应变损失速率加快,冻胀应变逐渐降低.

The freeze-thaw cycle tests were carried out on concrete cylindrical members with different stress levels, and in the process of freeze-thaw cycle, the development law of frost heave strain of concrete in the whole process of freeze-thaw was obtained by dynamic simulation method. The experimental results showed that the frost heaving strain increased with the decrease of temperature during the freeze-thaw cycle, and decreased with the rise of temperature. With the increase of freeze-thaw cycles, the effective strain of reinforcement gradually decreased, the upper envelope of the freeze-heave strain hysteresis ring increased, and the residual strain increased. With the increase of stress level, the effective strain loss rate of reinforcement accelerated and the frost heaving strain decreased gradually.

引言
1 试验概况
2 试验结果分析与讨论
3 结论

表1 混凝土配合比
Tab.1 Concrete mix

图1 试件张拉
Fig.1 Specimen tension

表2 混凝土圆柱体构件参数<br/>Tab.2 Parameters of concrete cylinder specimens

表2 混凝土圆柱体构件参数
Tab.2 Parameters of concrete cylinder specimens

图2 残余应变随温度变化规律<br/>Fig.2 Variations of residual strain with temperature

图2 残余应变随温度变化规律
Fig.2 Variations of residual strain with temperature

图3 C30混凝土圆柱体构件表面裂缝开展情况(C30-16)<br/>Fig.3 Surface crack development of C30 concrete cylinder members(C30-16)

图3 C30混凝土圆柱体构件表面裂缝开展情况(C30-16)
Fig.3 Surface crack development of C30 concrete cylinder members(C30-16)

图4 C40混凝土圆柱体构件表面裂缝开展情况(C40-32)<br/>Fig.4 Surface crack development of C40 concrete cylinder members(C40-32)

图4 C40混凝土圆柱体构件表面裂缝开展情况(C40-32)
Fig.4 Surface crack development of C40 concrete cylinder members(C40-32)

图5 冻融全过程混凝土构件钢筋应变<br/>Fig.5 Steel reinforcement strain of concrete members during freeze-thaw process

图5 冻融全过程混凝土构件钢筋应变
Fig.5 Steel reinforcement strain of concrete members during freeze-thaw process

图6 混凝土圆柱体构件冻胀应变滞回环<br/>Fig.6 Frost heaving strain hysteresis ring of concrete cylinder members

图6 混凝土圆柱体构件冻胀应变滞回环
Fig.6 Frost heaving strain hysteresis ring of concrete cylinder members

图7 混凝土圆柱体构件残余应变<br/>Fig.7 Residual strain of concrete cylinder members

图7 混凝土圆柱体构件残余应变
Fig.7 Residual strain of concrete cylinder members

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备注

引言

1 试验概况

2 试验结果分析与讨论

3 结论

期刊信息