The field source-point encryption technique based on the layout of the transducers, the scheme of reverse virtual ray path pair of omitting-receiving transducers, the improved SIRT algorithm considering the whole field correction, and the computed tomographic image post-processing technology, etc., were proposed respectively to improve the ultrasonic tomography effect of the RC pile foundations in view of the test characteristics of reinforced concrete (RC) pile foundation that the vertical dimension of cross-section area between two acoustic tubes is significantly larger than that of the horizontal dimension and the transducer spacing is relatively sparse. The ultrasonic tomography omitting and receiving transducer signals under different working conditions were simulated by using the finite element analysis software ABAQUS. Condition parameters that affect imaging effects were analyzed. Results show that it is quicker and more accurate to locate and quantify the potential defect among the cross-section area between two acoustic tubes by employing the proposed algorithms. The calculation reliability of the algorithm is high.
Ke WANG,Jun-tao WU,Zhe YU,Chi-xuan XIANG,Kui-hua WANG. Optimization of ultrasonic tomography technology for concrete pile foundation. Journal of ZheJiang University (Engineering Science), 2023, 57(4): 805-813.
Fig.1Schematic of field source-point distribution based on transducer layout size densification
Fig.2Positional relationship between source point and sub-level source point
Fig.3Schematic of calculated ray path in homogeneous medium field using Dijkstra algorithm
Fig.4Schematic of two-level decomposition structure of image wavelet
Fig.5Ultrasonic tomography (four-level decomposition and reconstruction using db7 wavelet)
Fig.6Image of modified relative value of wave velocity (four-level decomposition and reconstruction using db7 wavelet)
Fig.7Numerical simulation of ultrasonic testing of pile foundation
Fig.8Influence of 8-node sub-level source points adjacent to source point on tomography image
Fig.9Influence of 16-node sub-level source points adjacent to source point on tomography image
Fig.10Original ultrasonic tomography and image of modified relative value of wave velocity（Lv = 4.00 m，nrc = 10）
Fig.11Original ultrasonic tomography and image of modified relative value of wave velocity (Lv = 4.00 m，nrc = 20)
Fig.12Original ultrasonic tomography and image of modified relative value of wave velocity（βe = 1）
Fig.13Original ultrasonic tomography and image of modified relative value of wave velocity（βe = 5）
Fig.14Original ultrasonic tomography and image of modified relative value of wave velocity（rd = 0.10 m，rx= 0.00 m，ry= 0.00 m）
Fig.15Original ultrasonic tomography and image of modified relative value of wave velocity (rd = 0.20 m，rx= 0.00 m，ry= 0.00 m，vd = 3000 m/s)
[2]
王奎华, 谢康和, 曾国熙 变截面阻抗桩受迫振动问题解析解及 应用[J]. 土木工程学报, 1998, 31 (6): 56- 67 WANG Kui-hua, XIE Kang-he, ZENG Guo-xi An analytical solution to force vibration of foundation pile under exciting force and its application[J]. China Civil Engineering Journal, 1998, 31 (6): 56- 67
[3]
吴君涛, 王奎华, 高柳, 等 考虑桩身材料阻尼的桩基纵向振动 积分变换解及其应用[J]. 岩石力学与工程学报, 2017, 36 (9): 2305- 2312 WU Jun-tao, WANG Kui-hua, GAO Liu, et al Study on longitudinal vibration of a viscoelastic pile by integral transformation and its application[J]. Chinese Journal of Rock Mechanics and Engineering, 2017, 36 (9): 2305- 2312
[4]
WU J, WANG K, GAO L, et al Study on longitudinal vibration of a pile with variable sectional acoustic impedance by integral transformation[J]. Acta Geotechnica, 2019, 14 (6): 1857- 1870
doi: 10.1007/s11440-018-0732-8
[5]
DAVIS A Nondestructive evaluation of existing deep foundations[J]. Journal of Performance of Constructed Facilities, 1995, 9 (1): 57- 74
doi: 10.1061/(ASCE)0887-3828(1995)9:1(57)
[6]
黄大治, 陈龙珠 旁孔透射波法检测水泥搅拌桩的三维有限元 分析[J]. 上海交通大学学报, 2007, 41 (6): 960- 964 HUANG Da-zhi, CHEN Long-zhu 3D finite element analysis of parallel seismic method for integrity of cemented soil columns[J]. Journal of Shanghai Jiaotong University, 2007, 41 (6): 960- 964
doi: 10.3321/j.issn:1006-2467.2007.06.023
[7]
陈龙珠, 赵荣欣 旁孔透射波法确定桩底深度计算方法评价[J]. 地下空间与工程学报, 2010, 6 (1): 157- 161 CHEN Long-zhu, ZHAO Rong-xin On determination of pile length with parallel seismic testing for existing structure[J]. Chinese Journal of Underground Space and Engineering, 2010, 6 (1): 157- 161
doi: 10.3969/j.issn.1673-0836.2010.01.029
[8]
吴君涛, 王奎华, 肖偲, 等 弹性支承桩周围土振动响应解析解 及其波动规律研究[J]. 岩石力学与工程学报, 2018, 37 (10): 2384- 2393 WU Jun-tao, WANG Kui-hua, XIAO Si, et al The analytical solution of soil around elastic bearing pile and its dynamic law studies[J]. Chinese Journal of Rock Mechanics and Engineering, 2018, 37 (10): 2384- 2393
[9]
WU J, WANG K, EL NAGGAR M Dynamic soil reactions around pile-fictitious soil pile coupled model and its application in parallel seismic method[J]. Computers and Geotechnics, 2019, 110 (6): 44- 56
[10]
WU J, EL NAGGAR M, WANG K Analytical model for laterally loaded soil-extended pile shaft applied to verifying the applicability of lateral PS method[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2021, 147 (10): 04021103
doi: 10.1061/(ASCE)GT.1943-5606.0002636
[11]
CHERNAUSKAS L, PAIKOWSKY S. Defect detection and examination of large drilled shafts using a new cross-hole sonic logging system [C]// Performance Confirmation of Constructed Geotechnical Facilities. Amherst: ASCE, 2000.
[1]
王奎华, 谢康和, 曾国熙 有限长桩受迫振动问题解析解及其应 用[J]. 岩土工程学报, 1997, 19 (6): 27- 35 WANG Kui-hua, XIE Kang-he, ZENG Guo-xi Analytical solution to vibration of finite length pile under exciting force and its application[J]. Chinese Journal of Geotechnical Engineering, 1997, 19 (6): 27- 35
doi: 10.3321/j.issn:1000-4548.1997.06.007
[12]
LI D, ZHANG L, TANG W Reliability evaluation of cross-hole sonic logging for bored pile integrity[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2005, 131 (9): 1130- 1138
doi: 10.1061/(ASCE)1090-0241(2005)131:9(1130)
[13]
WHITE B, NAGY M, ALLIN R. Comparing cross-hole sonic logging and low-strain integrity testing results [C]// Proceedings of the 8th International Conference on the Application of Stress Wave Theory to Piles. Lisbon: IOS Press, 2008.
[14]
张杰, 沈霄云, 刘明贵 智能化桩基超声波CT检测系统研究[J]. 岩土力学, 2009, 30 (4): 1197- 1200 ZHANG Jie, SHEN Xiao-yun, LIU Ming-gui Study of intelligent pile ultrasonic CT testing system[J]. Rock and Soil Mechanics, 2009, 30 (4): 1197- 1200
doi: 10.3969/j.issn.1000-7598.2009.04.059
张美根, 程冰洁, 李小凡, 等 一种最短路径射线追踪的快速算法[J]. 地球物理学报, 2006, 49 (5): 1467- 1474 ZHANG Mei-gen, CHENG Bing-jie, LI Xiao-fan, et al A fast algorithm of shortest path ray tracing[J]. Chinese Journal of Geophysics, 2006, 49 (5): 1467- 1474
doi: 10.3321/j.issn:0001-5733.2006.05.026
[17]
王东鹤, 陈祖斌, 刘昕, 等 地震波射线追踪方法研究综述[J]. 地球物理学进展, 2016, 31 (1): 344- 353 WANG Dong-he, CHEN Zu-bin, LIU Xin, et al Review of the seismic ray tracing method[J]. Progress in Geophysics, 2016, 31 (1): 344- 353
doi: 10.6038/pg20160140
[18]
杨杰, 王浩多, 程琳 混凝土结构内部缺陷超声波CT检测图像特征[J]. 水电能源科学, 2019, 37 (11): 127- 130 YANG Jie, WANG Hao-duo, CHENG Lin Experimental study on image characteristics of ultrasonic CT detection of internal defects in concrete structures[J]. Water Resources and Power, 2019, 37 (11): 127- 130
[19]
SU B, ZHANG Y, PENG L, et al The use of simultaneous iterative reconstruction technique for electrical capacitance tomography[J]. Chemical Engineering Journal, 2000, 77 (1/2): 37- 41
[20]
WOLF D, LUBK A, LICHTE H Weighted simultaneous iterative reconstruction technique for single-axis tomography[J]. Ultramicroscopy, 2014, 136 (1): 15- 25
[21]
李莉, 胡建平 克里金插值算法在等高线绘制中的应用[J]. 天津城市建设学院学报, 2008, 14 (1): 68- 71 LI Li, HU Jian-ping Application of Kriging interpolation in contour creation[J]. Journal of Tianjin Institute of Urban Construction, 2008, 14 (1): 68- 71
[22]
金元, 靳海水 小波分析方法在混凝土检测中的应用[J]. 无损检测, 2003, 25 (12): 4 JIN Yuan, JIN Hai-shui Wavelet analysis and its application to the testing of concrete[J]. Nondestructive Testing, 2003, 25 (12): 4
doi: 10.3969/j.issn.1000-6656.2003.12.005
SHI Chun-fei, SUN Yi, WANG Xiao-ping. Data processing methods of SPRi sensor[J]. Journal of ZheJiang University (Engineering Science), 2018, 52(4): 657-662.
NI Hong-bo, DENG Jun-quan, SHI Xiang-nan, ZHOU Xing-she,ZHAO Wei-chao, SONG Ya-long, JIA Jiang-bo. Sleep staging methods using pulse frequency variability[J]. Journal of ZheJiang University (Engineering Science), 2017, 51(3): 572-576.
