A simulation and application of cross-well ultra-high-density resistivity imaging in the detection of foundation piles
CHAI Lun-Wei1,2()
1. China Railway First Survey and Design Institute Group Co., Ltd., Xi'an 710043, China 2. State Key Laboratory of Rail Transit Engineering Informatization, Xi'an 710043, China
To improve the detection level of foundation piles and reduce major potential safety hazards, this study established three geoelectric models corresponding to a single pile, long-short piles, and a pile group through the 2.5D forward and inverse numerical simulations using the cross-well ultra-high-density resistivity imaging technology and analyzed the response characteristics and regularity of these models. Given the complex detection environment of foundation piles, this study further expounded the application characteristics and effects of the technology by combining two cases for the detection of the burial depths of piles. The results are as follows. The cross-well ultra-high-density resistivity imaging technology enjoys the advantages of high precision and flexible and convenient construction when being applied to the detection of pile buried depth. It can detect the lengths of foundation piles on a large scale rather than detecting one foundation pile using one detection hole, thus greatly improving the detection level of the burial depths of foundation piles.
柴伦炜. 井间超高密度电法探测基桩的模拟及应用[J]. 物探与化探, 2022, 46(5): 1283-1288.
CHAI Lun-Wei. A simulation and application of cross-well ultra-high-density resistivity imaging in the detection of foundation piles. Geophysical and Geochemical Exploration, 2022, 46(5): 1283-1288.
Zhao Z D, Sugimoto S Q. Analysis and research on low strain integrity testing of pile foundation[J]. Earthquake Engineering and Engineering Vibration, 1995, 15(4): 104-112.
Jiang W L, Zhu G F, Zhang J. A direct dynamic measurement method of single pile bearing capacity[J]. Rock and Soil Mecha-nics, 2020, 41(10): 3500-3508.
Liu D, Li H. Application of geophysical detection method in stone arch bridge disease remediation project[J]. Geophysical and Geochemical Exploration, 2012, 20(5): 119-123.
Li W M, Wu S L, Yi Q. Methods for quantitative interpretation using tube wave information[J]. Geophysical and Geochemical Exploration, 2017, 41(2): 311-315.
Chen Y D, Chen S, Yu Y. Study on the macro and meso working behaviors of the combined pile foundation with long and short piles[J]. Chinese Journal of Underground Space and Engineering, 2015, 11(3): 700-705.
[7]
Zhe J, Greenhalgh S, Marescot L. Multichannel, full waveform and flexible electrode combination resistivity-imaging system[J]. Geophysics, 2007, 72(2): 592-603.
Chai L W, Tang G Y, Wang G Q, et al. The application of ultra-high-density cross-hole resistivity imaging in the buried depth detection of cast-in-place piles[J]. Journal of Engineering Geophysics, 2021, 18(2): 252-256.
[9]
Zhe J, Greenhalgh S A. A new kinematic method for mapping seismic reflectors[J]. Geophysics, 2010, 64(5): 1594-1602.
doi: 10.1190/1.1444663
[10]
Zhe J, Greenhalgh S A. Prestack multicomponent migration[J]. Geophysics, 1997, 62(2): 598-613.
doi: 10.1190/1.1444169
Su B, Liu X L, Wei X B, et al. Detection of caves by ultra-high density resistivity method between wells[J]. Geophysical and Geochemical Exploration, 2021, 45(5): 1354-1358.
Zhang J Y, Chen Z F. Comparative study on the method of determining the depth of pile bottom by side hole transmission wave method[J]. Chinese Journal of Underground Space and Engineering, 2018, 14(5): 1331-1337.
Hu F P, Ou C C, Fu M R. Numerical simulation of CT exploration of karst cave cross-hole resistivity under different filling media[J]. China Karst, 2019, 38(5): 766-773.
Zhou F, Qu W, Chen J. Engineering practice of end-bearing pile composite pile foundation in karst area[J]. Chinese Journal of Underground Space and Engineering, 2016, 12(2): 489-495.
Cao Q, Xiang W, Jia H L, et al. Application of cross-hole ultra-high density resistivity method in the detection of spherical weathered granite bodies[J]. Journal of Engineering Geology, 2013(5): 60-65.
Gong T C, Yang Q, Huang M T, et al. Analysis of the influence of the construction process of the double-arch tunnel on the pile foundation of the existing building[J]. Chinese Journal of Underground Space and Engineering, 2019, 15(4): 1172-1179.
Zhang W J, Li S C, Su M X, et al. Urban subway cave detection method based on cross-well resistivity imaging[J]. Journal of Shandong University:Engineering Science Edition, 2014, 44(3): 75-82.
Huang X M. Study on the protection scheme of the shield tunnel underneath the existing bridge piles[J]. Chinese Journal of Underground Space and Engineering, 2012, 8(3): 557-561,636.