An optimization of the work disruption by 3D cavity mapping using GPR: A new sewerage project in Torrente (Valencia, Spain)

Abstract

This paper describes the inspection for cavity detection in an urban area in Torrente (Valencia, Spain). A shallow cavity was found during excavation works for a sewerage project. Digging activities were stopped immediately and a GPR survey was required to reorganize the sewerage planning. The 3D GPR-mapping pinpointed cavities mostly on one side of the street. As a result, the sewerage system layout was moved to the side of the street where poor cavity evidences were detected. GPR technique is helpful for minimizing costs, time, work safety risks and inconveniences to neighborhood during civil engineering works, especially in urbanized areas.Highlights 1  3D GPR data has been used for cavity detection in urbanized areas. 2  3D representations of GPR data facilitate interpretation in civil engineering. 3  GPR survey reduces work safety risks in urbanized karst hazardous areas. 4  Civil engineering projects including GPR are cost-effective and time-reducing. Highlights Graphical Abstract Minimizing street work disruption by mapping cavities 1 derived from 3D GPR-data: a new sewerage project in 2 Torrente (Valencia, Spain) Abstract 13 This paper describes the inspection for cavity detection in an urban area in Torrente 14 (Valencia, Spain). A shallow cavity was found during excavation works for a sewerage 15 project. Digging activities were stopped immediately and a GPR survey was required to 16 reorganize the sewerage planning. The 3D GPR-mapping pinpointed cavities mostly on 17 one side of the street. As a result, the sewerage system layout was moved to the side of 18 the street where poor cavity evidences were detected. GPR technique is helpful for 19 minimizing costs, time, work safety risks and inconveniences to neighborhood during 20 civil engineering works, especially in urbanized areas.21 22 23 *Manuscript Click here to view linked References 2 Keywords 24 street work disruption; ground-penetrating radar; GPR; cavity; cave hazards; 3D 25 mapping; sewerage project 26 27 130 depth of 1.5 m projected excavation for sewer pipe. Amplitude slice maps from the 3D 131 model were used to identify irregularities at a constant depth. Besides, transparent 132 visualization of the 3D GPR data set was conducted for revealing main subsurface 133 anomalies. 134The main objective was to define the location, shape and depth of the cavities detected. 135The results can be enriched when visualized as a volumetric rendering. This procedure 136 allows anyone to reckon and understand how the subsurface area under study looks. 137 Maps and 3D representations allow for the characterization of the radar data, for 157 depth-slices are identified at 0.5, 1.0, 1.5 and 2.0 meter-depth. The maximum and 158 minimum amplitude ranges according to the amplitude-color scale characterize the 159 cavities filled with air in the subsurface study site. Moreover, the isosurface rendering 160 technique enabled visualizing the whole subterranean structures defined by karst

Characterization of complex groundwater flows in the environment of singular buildings by combining hydrogeological and non‐destructive geophysical (ground‐penetrating radar) techniques: Punta Begoña Galleries (Getxo, Spain)

“…Since the water content influences the electromagnetic response (Garcia‐Garcia et al, ; Lunt et al, ; Pérez‐Gracia et al, ), two GPR data acquisition surveys were carried out on the cliff top for two different hydrodynamic periods: a period of intense rains and a dry period. Radar reflections (profiles 41 to 49) were correlated with the stratigraphy derived from field observations and from borehole testing.…”

“…Over the past decades, GPR has been employed to resolve various geological and engineering issues, including, among others, soil water content measures (Galagedara, Parkin, & Redman, ; Grote, Anger, Kelly, Hubbard, & Rubin, ; Huisman & Bouten, ; Huisman, Sperl, Bouten, & Verstraten, ; van Overmeeren, Sariowan, & Gehrels, ; Weiler, Steenhuis, Boll, & Kung, ), soil moisture mapping at the field scale (Grote, Hubbard, & Rubin, ; Minet, Bogaert, Vanclooster, & Lambot, ; Weihermüller, Huisman, Lambot, Herbst, & Vereecken, ), and identification of near‐surface structures and seepage paths (Birken & Versteeg, ; Klenk, Jaumann, & Roth, ; Neal, ; Su, Xu, Geng, & Liang, ; Trinks, Wachsmuth, & Stümpel, ). Regarding the application of GPR in rock massifs, its main uses are related to the identification of major discontinuities and fractures, particularly in karst environments (Chamberlain, Sellers, Proctor, & Coard, ; Deparis, Garambois, & Hantz, ; Garcia‐Garcia, Valls‐Ayuso, Benlloch‐Marco, & Valcuende‐Paya, ; Grandjean & Gourry, ; Pueyo Anchuela, Casas‐Sainz, Soriano, & Pocoví‐Juan, ); for less clear features and structures, the contrast of GPR images along with direct observations allows calibration and validation of the results (Fernandes, Medeiros, Bezerra, Oliveira, & Cazarin, ; Longoni et al, ; Pipan, Forte, Guangyou, & Finetti, ).…”

DL-Aided Underground Cavity Morphology Recognition Based on 3D GPR Data

“…Ground-penetrating radar (GPR) has gradually been applied to the detection and perception of underground cavities [2], owing to its nondestructive inspection, strong penetrating ability, and high-precision characteristics. GPR transmitters emit electromagnetic (EM) waves into the surface at multiple spatial positions, and then the reflected signal can be measured by the GPR receiver to establish a two-dimensional (2D) GPR image.…”

Hamiltonian Monte Carlo for Simultaneous Interface and Spatial Field Detection (HMCSISFD) and its application to a piping zone interface detection problem

“…Clear and accurate detection of the interface can enable more informed real‐time remediation measures to be implemented. For example, pinpoint detection of weak zones near an under‐construction project can indicate safer areas in the vicinity of the original plan where the project may be shifted, without incurring major financial loss 8 . In this paper, the target interface detection problem is one of detecting the piping zone beneath embankments and levees.…”