不规则动荷载作用下砂土孔压特性试验研究

潘坤; 杨仲轩

doi:10.11779/CJGE2017S1016

不规则动荷载作用下砂土孔压特性试验研究 English Version

潘坤,
杨仲轩^,

浙江大学建筑工程学院,浙江杭州 310058

基金项目: 国家自然科学基金项目（51578499,51761130078）; 国家; 重点基础研究发展计划项目（“973”计划）（2015CB057801）; 国家重; 点研发计划（2016YFC0800204）

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作者简介:
潘坤(1990-),男,安徽安庆人,博士研究生,主要从事砂土动力特性等方面的研究。E-mail:pk2013@zju.edu.cn。

通讯作者:
杨仲轩，E-mail：zxyang@zju.edu.cn

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- 收稿日期: 2016-11-27
- 发布日期: 2017-11-19

Pore pressure characteristics of sand subjected to irregular loadings

PAN Kun,
YANG Zhong-xuan^,

Department of Civil Engineering, Zhejiang University, Hangzhou 310058, China

摘要

摘要: 以多组人工调制的不规则正弦波荷载作为输入荷载,对饱和松砂开展一系列动三轴试验,探讨应力时程中不同脉冲幅值和脉冲顺序对砂土孔压特性的影响。试验结果表明,出现更早、幅值更大的应力脉冲更易导致孔隙水压力的发展,同时也更易诱发砂土液化。进一步地,峰值应力之前和之后的脉冲波组对孔压发展的影响有所不同。此外,不同荷载模式下,饱和松砂动孔压比与振次比存在近似唯一关系。根据砂土孔压特性,引入单位体积剪切功并考察其与超静孔压的内在关联,得到了孔压比与正交化剪切功的归一化关系。这一关系具有应力路径无关性,受动荷载不规则性影响较小,但与材料特性即土体种类有关。
- 不规则动荷载 /
- 脉冲 /
- 动三轴试验 /
- 饱和松砂 /
- 孔压累积
Abstract: A series of undrained cyclic triaxial tests are conducted under various types of artificial irregular loadings to investigate the combined effect of loading amplitude and sequence on the pore pressure characteristics of saturated loose sand. The results indicate that the earlier the higher-amplitude stress pulses arrive in a time history, the larger the pore pressure generation and thus the lower liquefaction resistance the sand samples display. The stress pulses prior to or after the arrival of the maximum spike stress play different role in the development of the pore pressure. In addition, a fairly unique relationship exists between the accumulated pore pressures and the normalized loading cycles. In view of this, the concept of shear work per unit volume is introduced to investigate the evolutionary trend of the excess pore water pressure generation during irregular loadings. The relationship between the pore pressure ratio and the normalized shear work is barely affected by the amplitude and the sequence of stress pulses in the irregular loadings, but shown to be dependent on the type of sand.
- irregular loading /
- stress pulse /
- cyclic triaxial test /
- saturated loose sand /
- pore pressure accumulation

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参考文献(13)

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[2]	陈国兴, 刘雪珠. 南京粉质黏土与粉砂互层土及粉细砂的振动孔压发展规律研究[J]. 岩土工程学报, 2004, 26(1): 79-82. (CHEN Guo-xing, LIU Xue-zhu. Study on dynamic pore water pressure in silty clay interbeded with fine sand in Nanjing[J]. Chinese Journal of Geotechnical Engineering, 2004, 26(1): 79-82. (in Chinese))
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不规则动荷载作用下砂土孔压特性试验研究 English Version

作者简介: 潘坤(1990-),男,安徽安庆人,博士研究生,主要从事砂土动力特性等方面的研究。E-mail:pk2013@zju.edu.cn。

通讯作者: 杨仲轩，E-mail：zxyang@zju.edu.cn

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出版历程

Pore pressure characteristics of sand subjected to irregular loadings

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出版历程

目录

作者简介:
潘坤(1990-),男,安徽安庆人,博士研究生,主要从事砂土动力特性等方面的研究。E-mail:pk2013@zju.edu.cn。

通讯作者:
杨仲轩，E-mail：zxyang@zju.edu.cn