Recent Advances in Geotechnical Post-earthquake Reconnaissance

Jonathan D Bray,James D Frost,Fernando E Garcia,Ellen M Rathje

doi:10.3389/fbuil.2019.00005

Abstract

Field observations are particularly important in geotechnical engineering, because it is difficult to replicate in the laboratory the response of soil deposits built by nature over thousands of years. Detailed mapping of damaged and undamaged areas provides the data for the well-documented case histories that drive the development of many current design procedures. Thus, documenting key insights from earthquakes advances research and practice. This has been a primary goal of the National Science Foundation-sponsored Geotechnical Extreme Events Reconnaissance (GEER) Association since its inception almost 20 years ago. New technologies are continually employed by GEER teams to capture ground deformation and its effects. These technologies include Light Imaging Detection and Ranging (LIDAR) and Structure-from-Motion (SfM) image processing techniques for generating and visualizing three-dimensional point cloud data sets. New sensor deployment platforms such as Unmanned Aerial Vehicles (UAVs) are playing an integral role in the data collection process. Unanticipated observations from major events often catalyze new research directions. An overview of some of these recent integrated technology deployments and their role at the core of earthquake disaster analysis is presented. Important advancements are possible through post-event research if their effects are captured and shared effectively.

Highlights

There have been major improvements in scientific understanding and subsequent advances in earthquake engineering practice in the aftermath of significant earthquakes
Reconnaissance teams from the U.S National Science Foundation (NSF)-sponsored Geotechnical Extreme Events Reconnaissance (GEER) Association strive to learn from these events and develop the insight and understanding that will enable scientists and engineers to evaluate and mitigate the effects of future earthquakes
The geotechnical engineering profession has a rich tradition of understanding the need to develop and apply new technologies and techniques that document the effects of earthquakes on urban infrastructure

Summary

INTRODUCTION

There have been major improvements in scientific understanding and subsequent advances in earthquake engineering practice in the aftermath of significant earthquakes. For each of the 58 GEER responses, web-based reports were typically published within 2 months of completion of the field reconnaissance activities These reports are archived on the GEER website (www.geerassociation.org) and are frequently used by other individuals and agencies planning post-event studies as well as for longer term research purposes. Often the evaluation and mitigation procedures recommended in engineering practice are based on previously documented field case histories that describe poor and good performance during significant events. As Bray and Travasarou (2007) and Rathje and Antonakos (2011), have been validated by demonstrating they capture the observed seismic performance of earth systems and natural slopes during actual events These and other commonly employed geotechnical earthquake engineering procedures require continual re-evaluation and revision when insightful well-documented field case histories emerge. If the geotechnical engineering profession does not continue to look for new insights following future earthquakes with more extensive data sets, important research opportunities will be lost

RECONNAISSANCE METHODS AND ACTIVITIES

Findings

CONCLUSIONS