The Usefulness of Seismic Surveys for Geotechnical Engineering in Karst: Some Practical Examples

Abstract

Having in mind uncertainties linked with the nature of rock masses, it is a challenge for geotechnical engineers to characterize them in a credible manner, especially if the rock mass in question is a notoriously complex karst with its distinctive features such as voids and discontinuities. A large range of geophysical methods are useful tools in the characterization efforts and their utilization in karst environments nowadays is a non-negotiable requirement, even though near-surface scattering significantly affects the acquired data. This paper demonstrates the versatile applications of seismic geophysical methods for geotechnical engineering in karst, from mapping of near-surface karstic features to the application of elastic wave velocities in determination of small to large strain stiffness of karst. The highlighted practical examples offer a step forward from the traditional interpretation of seismic surveys, making them a prosperous tool in geotechnical engineering investigation works, design and quality control campaign.

Sinkholes induced by the Petrinja M6.2 earthquake and guidelines for their remediation

“…There are many studies dealing with the methods and techniques for the evaluation of a depth and extent of the subsurface anomaly. The investigation protocols are especially complex in karst, as noted by Bačić et al [9], where multiple methods and data-gathering techniques should be utilized. The first step should include the analysis of existing data through consideration of existing geological maps and aerial photographs.…”

“…An interesting example of usefulness of geophysical methods in ground characterization is given by Bačić et al [9], for a sinkhole of approximately 3 m in depth and of 10 m 2 aperture area, opened between two lanes of a national highway in Croatia, Figure 4a. This immediately alert the infrastructure managers to detect its origin and extent so that appropriate remediation measures be taken.…”

Identification of subsidence hazard zone by integrating engineering geological mapping and electrical resistivity tomography in Gunung Kidul karst area, Indonesia

“…The classic method for determining the presence of a cavity below the surface is drilling. However, a more economical and effective solution is to implement geophysical surveys to reduce the number of drilling and increase the accuracy of test holes' placement for verification (Bacic et al, 2020). In addition, engineering geological mapping is also beneficial for identifying the presence and pattern of geological structures observed directly (Martinez-Grana et al, 2013;Phillips et al, 2019).…”

Modelling 3D elastodynamic wave scattering due to density and Lamé parameter contrasts of near‐surface scatterers

“…Thus, one or more of these methods are chosen depending on the nature of the subsurface target. Over the years, seismic (Tran et al ., 2013; Benjumea et al ., 2016; Chen et al ., 2017; Bačić et al ., 2020; Mouzakiotis et al ., 2020), magnetic (Alfouzan et al ., 2016; Mandal et al ., 2019) and electrical and electromagnetic (Colombo et al ., 2016; Bilik et al ., 2018; Mandal et al ., 2019; Ba et al ., 2020) based methods are commonly used in near‐surface explorations. Seismic methods for near‐surface investigations are especially wide ranging in both scale and methodology, with applications in both body wave and surface waves.…”