Experimental Studies on Seismic Behavior of Exterior SRUHSC Joints

钢骨超高强混凝土边节点抗震性能试验研究

刘 伟,贾金青

（大连理工大学 海岸和近海工程国家重点实验室,辽宁 大连,116024）

创新点说明：

1)研究了轴压比对钢骨超高强混凝土边节点破坏形态的重要影响,随着轴压比提高,破坏形态由梁塑性铰延性破坏变为节点核心区剪切破坏,当轴压比超过试验轴压比0.38,破坏形态转变为小偏心受压破坏。

2)研究了不同轴压比下钢骨超高强混凝土边节点抗震性能,包括承载力、延性、剪切变形、应力应变,在此基础上,提出了钢骨超高强混凝土边节点的轴压比限值。

3)提出了钢骨超高强混凝土边节点轴压比限值下的最小配箍率。

研究目的：

主要解决钢骨超高强混凝土边节点抗震设计问题,提出这种新型结构体系的轴压比限值及最小配箍率。

研究方法：

开展了钢骨超高强混凝土边节点的低周往复试验研究,使用IMC数据采集系统采集数据,节点核心区采用LVDT测量剪切变形,并进行理论分析。

结果：

1)随着轴压比提高,破坏形态由梁塑性铰延性破坏变为节点核心区剪切破坏,当轴压比超过试验轴压比0.38,破坏形态转变为小偏心受压破坏。

2)当轴压比提高80%时,构件的延性系数下降57%。

3)当试验轴压比小于0.38时,提高轴压比能提高构件的初始刚度,而当试验轴压比超过0.38时,提高轴压比导致初始刚度下降,且刚度急速退化。

4)当试验轴压比小于0.38时,提高轴压比能提高构件的承载力,而当试验轴压比超过0.38时,提高轴压比承载力反而降低。

5)提出钢骨超高强混凝土边节点的轴压比限值0.38（设计轴压比0.65）,及对应的最小配箍率。

结论：

1)研究了轴压比对钢骨超高强混凝土边节点破坏形态的重要影响,随着轴压比提高,破坏形态由梁塑性铰延性破坏变为节点核心区剪切破坏,当轴压比超过试验轴压比0.38,破坏形态转变为小偏心受压破坏。

2)研究了不同轴压比下钢骨超高强混凝土边节点抗震性能,包括承载力、延性、剪切变形、应力应变,在此基础上,提出了钢骨超高强混凝土边节点的轴压比限值。

3)提出钢骨超高强混凝土边节点的轴压比限值0.38（设计轴压比0.65）,及对应的最小配箍率。

关键词：边节点,钢骨超高强混凝土结构,钢骨,轴压比

     

A new sensing skin for qualitative damage detection in concrete elements: Rapid difference imaging with electrical resistance tomography

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Observation and quantification of the fracture process zone for two magnesia refractories with different brittleness

In this paper, the formation of the fracture process zone (FPZ) of industrially produced magnesia spinel and magnesia refractories was analysed using digital image correlation (DIC). Compared to pure magnesia materials, the magnesia spinel materials exhibited a higher amount of microcracks, causing a larger FPZ. A critical displacement, where the cohesive stress between the crack faces decreases to zero, is determined by analysing the development of the localized zone. Critical displacement determined from the changes of the FPZ width and length is used to determine the onset of macro-cracking and locate the crack tip. The development of the fracture process zone for a magnesia spinel initiates before reaching the maximum load, and the onset of the macro-crack is in the post-peak region. The FPZ size increases until the formation of a macro-crack takes place, but decreases afterwards. For the magnesia refractory, no pronounced FPZ could be detected.     

沉箱码头地震液化任意拉格朗日欧拉方法大变形分析

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不同种类混凝土冻融循环后双轴压压统一强度准则

针对混凝土遭受冻融循环作用后强度降低导致寒冷地区混凝土结构耐久性和安全性不足的问题,基于已有的大量试验数据,以混凝土冻融损伤后的单轴抗压强度衰减规律为参数,对不同种类混凝土建立了考虑冻融循环次数影响的双轴压压统一强度准则,并与前人试验研究结果做了对比分析。结果表明,本文建立的统一强度准则能较好地预测混凝土冻融循环后的双轴抗压强度,为寒冷地区混凝土结构的安全性分析提供了参考。     

新型CFRP抗弯加固方法的试验研究

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混凝土细观刚体弹簧元法在劈裂试验中的应用

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Strain Transfer Coefficient Analyses for Embedded Fiber Bragg Grating Sensors in Different Host Materials

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Numerical Simulation of Flushing of Trapped Salt Water from a Bar-Blocked Estuary

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