Pull-out model test of anti-floating multi-bell-shaped anchor under cyclic loading

doi:10.16265/j.cnki.issn1003-3033.2024.06.0081

Abstract

Abstract:

In order to study the reasons for the deterioration of the anchor performance caused by groundwater variation, a series of physical model tests were employed to explore the anchorage enhancement of the expanded anchor in the anti-floating process. Firstly, a single pull-out test was carried out through the indoor model test, and the change of bearing capacity of multi-bell-shaped expanded anchor under different buried depths during the pull-out process was obtained. Secondly, according to the ultimate uplift bearing capacity obtained from the single pull-out test, the cyclic test was carried out to explore the evolution mechanism of the bearing performance of the multi-bell-shaped expanded anchor under different cyclic amplitudes, cyclic times and cyclic frequencies. Finally, the image particle velocity method (PIV) was used to analyze the deformation mechanism of the surrounding soil, and the variation characteristics of the surrounding soil displacement under single pulling-out and cyclic loading were obtained. The test results show that the axial load-displacement curve of the bell-shaped expansion anchor can be roughly divided into three stages: elasticity, vibration and failure. With the increase of buried depth, the ultimate bearing capacity and soil displacement of the anchor increase. Under the action of cyclic loadings, the increase of the cyclic load ratio, the number of cycles and the cycle frequency will weaken the bearing capacity of the anchors.

Key words: cyclic load, anti-floating, multi-bell-shaped expanded anchor, anchor pull-out, bearing capacity, soil displacement

CLC Number:

X935

CHEN Chen, YU Jie, LIU Zhe, XIE Shasha, YI Chengcheng. Pull-out model test of anti-floating multi-bell-shaped anchor under cyclic loading[J]. China Safety Science Journal, 2024, 34(6): 109-118.

Figures/Tables 21

Table 1

Fig.1

Table 2

Fig.2

Fig.3

Fig.4

Table 3

Table 4

Fig.5

Fig.6

Fig.7

Table 5

Fig.8

Fig.9

Table 6

Fig.10

Table 7

Fig.11

Fig.12

Fig.13

Fig.14

References 15

[1]	于贵, 李星, 舒中文, 等. 高层建筑地下室上浮变形特征及处置措施研究[J]. 地下空间与工程学报, 2020, 16(1):211-218.
	YU Gui, LI Xing, SHU Zhongwen, et al. Research on floating deformation characteristics and treatment measures of high-rise building basement[J]. Chinese Journal of Underground Space and Engineering, 2020, 16(1):211-218.
[2]	FUJITA K, UEDA K, KUSABUKA M. A method to predict the load-displacement relationship of ground anchors[J]. Revue Française de GÉotechnique, 1978, 3:58-62.
[3]	王勇华, 王小勇, 牛云彪, 等. 黄土地区压力型锚索锚固机理数值模拟研究[J]. 地下空间与工程学报, 2020, 16(增2):693-701.
	WANG Yonghua, WANG Xiaoyong, NIU Yunbiao, et al. Numerical simulation research on anchoring mechanism of compression anchors in loess areas[J]. Chinese Journal of Underground Space and Engineering, 2020, 16(S2):693-701.
[4]	赵象桌, 张宏伟, CAO Chen, 等. 大直径玻璃钢锚杆工作面帮支护性能试验研究[J]. 中国安全科学学报, 2019, 29(2):118-124.
	ZHAO Xiangzuo, ZHANG Hongwei, CAO Chen, et al. Experimental study on panel side supporting performance of large diameter FRP bolts[J]. China Safety Science Journal, 2019, 29(2):118-124.
[5]	夏元友, 陈晨, NI Qing. 透明土中连续球体型锚杆拔出机理研究[J]. 岩土工程学报, 2017, 39(5):804-812.
	XIA Yuanyou, CHEN Chen, NI Qing. Pull-out mechanism of continuous ball shape anchors in transparent soil[J]. Chinese Journal of Geotechnical Engineering, 2017, 39(5):804-812.
[6]	白顺果, 侯永峰, 张鸿儒. 交通荷载作用下饱和软基的模型试验及变形分析[J]. 中国安全科学学报, 2004, 14(12):108-110,107.
	BAI Shunguo, HOU Yongfeng, ZHANG Hongru. Model test and deformation analysis on saturated soft foundation under traffic loading[J]. China Safety Science Journal, 2004, 14(12):108-110,107.
[7]	陈秋南, 刘文骏, 赵磊军, 等. 充气锚杆循环荷载作用下的位移规律试验研究[J]. 地下空间与工程学报, 2019, 15(2):373-380.
	CHEN Qiunan, LIU Wenjun, ZHAO Leijun, et al. Experimental study on displacement law of inflatable anchor under cyclic loading[J]. Chinese Journal of Underground Space and Engineering, 2019, 15(2):373-380.
[8]	WHITE D J, TAKE W A, BOLTON M D. Soil deformation measurement using particle image velocimetry (PIV) and photogrammetry[J]. GÉotechnique, 2003, 53(7):619-631.
[9]	杨晓峰, 李伟, 姚兆明. 基于PIV技术的冲刷条件下水平桩-土变形机制研究[J]. 长江科学院院报, 2023, 40(2):102-108. doi: 10.11988/ckyyb.20210980
	YANG Xiaofeng, LI Wei, YAO Zhaoming. Study on horizontal deformation mechanism of pile-soil under scour condition based on PIV technique[J]. Journal of Yangtze River Scientific Research Institute, 2023, 40(2):102-108. doi: 10.11988/ckyyb.20210980
[10]	BS 8081: 2015, Codo of practice for ground anchorages[S].
[11]	芮瑞, 肖风钰, 程永辉, 等. 不同埋置深度下的锚板抗拔特性试验研究[J]. 岩土工程学报, 2023, 45(10):2032-2041.
	RUI Rui, XIAO Fengyu, CHENG Yonghui, et al. Experimental study on pull-out resistance of plate anchors at different buried depths[J]. Chinese Journal of Geotechnical Engineering, 2023, 45(10):2032-2041.
[12]	曹佳文, 彭文祥, 郭振斌, 等. 充气锚杆在砂土中变形与承载特性试验研究[J]. 中南大学学报:自然科学版, 2011, 42(5):1369-1374.
	CAO Jiawen, PENG Wenxiang, GUO Zhenbin, et al. Experimental study on deformation and bearing features of inflatable anchors in sands[J]. Journal of Central South University: Science and Technology, 2011, 42(5):1369-1374.
[13]	YBT 4659—2018,抗浮锚杆技术规程[S].
	YBT 4659-2018, Technical specification for anti-floating anchors[S].
[14]	夏元友, 陈晨, NI Qing. 基于透明土的4种锚杆拔出对比模型试验[J]. 岩土工程学报, 2017, 39(3):399-407.
	XIA Yuanyou, CHEN Chen, NI Qing. Comparative modelling of pull-out process of four different anchorages by using transparent soil[J]. Chinese Journal of Geotechnical Engineering, 2017, 39(3):399-407.
[15]	李元海, 朱合华, 靖洪文, 等. 基于数字照相的砂土剪切变形模式的试验研究[J]. 同济大学学报, 2007, 35(5):685-689.
	LI Yuanhai, ZHU Hehua, JING Hongwen, et al. Experimental investigation of shear deformation patterns in sands based on digital image correlation[J]. Journal of Tongji University: Natural Science, 2007, 35(5):685-689.

试验编号	锚固段尺寸/ (mm×mm)	扩体间距 L/mm	段数 n	H/m
J1	(30+80)×80	140	3	1
J2	(30+80)×80	140	3	2
J3	(30+80)×80	140	3	3
J4	(30+80)×80	140	3	2

试验编号	H/m	f/Hz	M/次	λ
FZ1	2	0.01	100	0.2
FZ2	2	0.01	100	0.3
FZ3	2	0.01	100	0.4
FZ4	2	0.01	100	0.5
FZ5	2	0.01	100	0.6
FZ6	2	0.01	100	0.7
CS1	2	0.01	10	0.3
CS2	2	0.01	50	0.3
CS3	2	0.01	10	0.5
CS4	2	0.01	50	0.5
CS5	2	0.01	10	0.7
CS6	2	0.01	50	0.7
PL1	2	0.025	100	0.3
PL2	2	0.050	100	0.3
PL3	2	0.025	100	0.5
PL4	2	0.050	100	0.5
PL5	2	0.025	100	0.7
PL6	2	0.050	100	0.7

试验编号	λ	M/次	f/Hz	F_t/N	S/mm	衰减率/%
FZ1	0.2	100	0.0.1	4 322.7	2.56	9.1
FZ2	0.3	100	0.0.1	4 249.8	3.80	10.6
FZ3	0.4	100	0.0.1	4 158	6.42	12.6
FZ4	0.5	100	0.0.1	4 149.9	7.74	12.8
FZ5	0.6	100	0.0.1	4 144.5	10.34	12.9
FZ6	0.7	100	0.0.1	3 820.5	20.69	19.7

编号	λ	M/次	f/Hz	F_t/N	S/mm	衰减率/%
CS1	0.3	10	0.01	4 617.0	3.18	3.0
CS2		50	0.01	4 244.2	3.69	10.8
FZ2		100	0.01	4 249.8	3.80	10.6
CS3	0.5	10	0.01	4 619.7	5.23	2.9
CS4		50	0.01	4 158.9	7.13	12.6
FZ4		100	0.01	4 149.9	7.74	12.8
CS5	0.7	10	0.01	4 621.8	10.06	2.8
CS6		50	0.01	4 079.2	16.25	14.3
FZ6		100	0.01	3 820.5	20.69	19.7

试验编号	λ	N/次	f/Hz	F_t/N	S/mm	衰减率/%
FZ2	0.3	100	0.01	4 249.8	3.80	10.6
PL1		100	0.025	4 261.5	2.93	10.4
PL2		100	0.05	4 280	2.82	10
FZ4	0.5	100	0.01	4 149.9	7.74	12.8
PL3		100	0.025	4 161.7	4.63	12.5
PL4		100	0.05	4 182.8	4.49	12.1
FZ6	0.7	100	0.01	3 820.5	20.69	19.7
PL5		100	0.025	3 825.8	10.92	19.6
PL6		100	0.05	3 832.5	7.80	19.4