Experimental investigation of reverse end bearing of offshore shallow foundations
Experimental investigation of reverse end bearing of offshore shallow foundations
复制标题
DOI：
10.1139/cgj-2012-0428
复制
发表时间：
2013-08
影响因子：
3.6
通讯作者：
Divya S. K. Mana;S. Gourvenec;M. Randolph
中科院分区：
文献类型：
--
作者：
Divya S. K. Mana;S. Gourvenec;M. Randolph
浅裙边基础能在中短期内调动端承的上扬阻力。然而，与压缩阻力相比，反端承载阻力的大小存在不确定性，以及基础裙边外表面与邻近土壤之间的间隙如何影响这一点。本文通过离心模型试验探讨了这一问题，研究了裙边埋置比对(i)与抗压能力相比的反端承载力大小，（ii）与上拔过程中自发吸力损失相关的上拔位移，以及（iii）沿裙边-土外部界面存在垂直间隙的影响。结果表明：(1)裙板-土界面完整的全密封基础可以调动相当于抗压能力的峰值上拔能力；(2)即使裙板嵌入比较低，通过较大的基础位移也可以保持反向端承力所需的吸力；(3)裙板-土界面外沿垂直间隙的存在导致在最小基础位移后顶板下吸力突然丧失。随后的抬升能力明显降低。
Shallow skirted foundations can mobilize uplift resistance from end bearing in the short to medium term. However, uncertainty exists over the magnitude of reverse end bearing resistance compared with resistance in compression, and how this might be affected by a gap between the external face of the foundation skirt and the adjacent soil. The study presented in this paper explores this problem through centrifuge model tests, investigating the effect of skirt embedment ratio on (i) the magnitude of reverse end bearing capacity compared with compression capacity, (ii) the uplift displacement associated with spontaneous loss of suction during uplift, and (iii) the existence of a vertical gap along the external skirt-soil interface. The results show that (i) peak uplift capacity equivalent to compression capacity can be mobilized for a fully sealed foundation with an intact skirt-soil interface, (ii) suction required for reverse end bearing can be maintained through considerable foundation displacement, even for a low skirt embedment ratio, and (iii) the presence of a vertical gap along the external skirt-soil interface causes abrupt loss of suction beneath the top plate after minimal foundation displacement, with subsequent uplift capacity being markedly reduced.