A5013189745- Geotechnical Engineering and Underground Structures
- Landslides and related hazards
- Landfill Environmental Impact Studies
- Geotechnical Engineering and Soil Stabilization
- Seismic Waves and Analysis
- Geotechnical Engineering and Soil Mechanics
- 3D Surveying and Cultural Heritage
- Geophysical Methods and Applications
- Geotechnical Engineering and Analysis
- Electrokinetic Soil Remediation Techniques
- Remote Sensing and LiDAR Applications
- Structural Health Monitoring Techniques
- earthquake and tectonic studies
- Seismic Performance and Analysis
- Dam Engineering and Safety
- Grouting, Rheology, and Soil Mechanics
- Robotics and Sensor-Based Localization
- Soil and Unsaturated Flow
- Flood Risk Assessment and Management
- Cryospheric studies and observations
- Geological Modeling and Analysis
- Tree Root and Stability Studies
- Infrastructure Maintenance and Monitoring
- Indoor and Outdoor Localization Technologies
- Earthquake Detection and Analysis
University of California, Berkeley
2006-2025
University of California System
2025
The Aerospace Corporation
2025
University of Michigan
2014-2024
ORCID
2021-2024
Missouri University of Science and Technology
2024
University of Puerto Rico-Mayaguez
2024
Berkeley College
2022
National Technical University of Athens
2022
Drexel University
2022
Coseismic landslides pose immediate and prolonged hazards to mountainous communities, provide a rare opportunity study the effect of large earthquakes on erosion sediment budgets. By mapping using high-resolution satellite imagery, we find that 25 April 2015 Mw7.8 Gorkha earthquake aftershock sequence produced at least 25,000 throughout steep Himalayan Mountains in central Nepal. Despite early reports claiming lower than expected landslide activity, our results show total number, area,...
Unmanned aerial vehicles (UAV), or drones, have become popular tools for practitioners and researchers alike. Recent years seen a significant increase in UAV uses many applications the fields of science engineering. A broad array research development UAVs has been reported literature. This paper provides summary review efforts related to with focus on civil infrastructure applications. First, guidance is provided looking newly incorporate into their efforts. The advantages disadvantages...
The unit weight of municipal solid waste (MSW) is an important parameter in engineering analyses landfill performance, but significant uncertainty currently exists regarding its value. A careful review reliable field data shows that individual landfills have a characteristic MSW profile. Based on situ and trends observed large-scale laboratory tests, hyperbolic relationship was developed to represent this Within the context profile, landfill-specific values depend primarily composition,...
A comprehensive large-scale laboratory testing program using direct shear (DS), triaxial (TX), and simple tests was performed on municipal solid waste (MSW) retrieved from a landfill in the San Francisco Bay area to develop insights about framework for interpretation of strength MSW. Stability analyses MSW landfills require characterization Although is variable difficult material test, its can be evaluated rationally reasonable estimates. The effects composition, fibrous particle...
Flash floods are common manifestations of extreme weather events and one the most severe natural hazards. In Europe, they have been responsible for 359 fatalities an economic loss totalling 67 million USD in past decade (EM-DAT), while their increasing severity is linked to climate change. Nevertheless, flash remain a poorly documented phenomenon due lack flow intensity data many affected watersheds. Based on thorough field investigation, including UAV-based 3D mapping material...
A procedure to characterize municipal solid waste (MSW) for geotechnical engineering purposes is developed based on experience with characterization and testing. Existing MSW classification systems are reviewed briefly, the field laboratory programs of two important projects presented. Findings influence waste's physical composition its mechanical response from these recent studies integrated develop a efficient collection relevant information landfill operation characteristics that most...
Representative dynamic properties of municipal solid waste (MSW) are required to perform reliable seismic analyses MSW landfills. A comprehensive large-scale cyclic triaxial laboratory testing program was performed on retrieved from a landfill in the San Francisco Bay area evaluate small-strain shear modulus, and strain-dependent normalized modulus reduction material damping ratio relationships MSW. The effects composition, confining stress, unit weight, time under confinement, loading...
This paper presents the results of large-size cyclic simple shear testing on three uniform gravels (Pea Gravel, 8-mm Crushed Limestone, and 5-mm Limestone), which varied in particle size angularity. Monotonic, cyclic, postcyclic response was assessed for these materials at two relative densities initial vertical effective stresses up to 400 kPa. Shear wave velocity measured each specimen so that laboratory field conditions could be compared. Particle angularity shown an important parameter...
The application of the Structure-from-Motion (SfM) methodology, as enabled by growth Unmanned Aerial Vehicle (UAV) technology, is expected to have significant impact in geotechnical engineering research and practice. SfM outputs are presented using selected projects examples, include orthophotos, 3D point clouds, three dimensional digital surface or terrain models. Repeated surveys allow for monitoring deformation patterns at a cm-level resolution. lessons learned from methodology twenty-six...
Abstract. We present field evidence and a kinematic study of rock block mobilized in the Ponti area by Mw = 6.5 earthquake near island Lefkada on 17 November 2015. A detailed survey was conducted using an unmanned aerial vehicle (UAV) with ultrahigh definition (UHD) camera, which produced high-resolution orthophoto digital terrain model (DTM). The sequence impact marks from trajectory ground surface identified verified. Earthquake characteristics were used to estimate acceleration slope...
Seven municipal solid waste (MSW) specimens with variable initial compositions were biodegraded in large (d = 300 mm, h 600 mm) laboratory landfill simulators under leachate-recirculation-enhanced anaerobic biodegradation conditions to investigate changes the biochemical and physical characteristics of waste, leachate biogas during biodegradation. The evolution time monitored three phases was presented empirically correlated. impact composition on process quantified. Although removal soluble...
Liquefaction assessment has primarily been performed using in situ penetration testing, but this practice become problematic for gravelly soils. For example, standard test (SPT)- or cone (CPT)-based correlations can unreliable owing to interference with large gravel particles, while the Becker Penetration Test, commonly used soil, be relatively expensive and requires conversion an equivalent sand blow count. As alternative, probabilistic liquefaction-triggering curves have developed based on...
The 2011 M W = 9.0 Tohoku-oki earthquake generated a large number of unique soil liquefaction case histories, including cases with strong ground motion recordings on liquefiable or potentially soils. We have compiled list 22 stations (SMS) where surface evidence was observed and 16 SMS underlain by geologically recent sediments fills not observed. Pre-earthquake standard penetration test data borehole shear wave velocity ( V s ) profiles are available for some stations, but critical...
Long-term settlement of municipal solid waste (MSW) in bioreactor and conventional landfills is caused by a number mechanisms. Laboratory tests landfill simulators allow for careful assessment each mechanism the factors that affect it. A systematic review synthesis 98 from 29 mesoscale simulator studies available literature are presented. divided into three phases: transitional phase, active biodegradation residual phase. Duration, strain, long-term compression ratio (equal to strain...
Abstract In 2017, hurricane Maria caused unprecedented damage and fatalities on the Caribbean island of Dominica. order to ‘build back better’ learn from processes causing damage, it is important quickly document, evaluate map changes, both in Dominica other high-risk countries. This paper presents an innovative relatively low-cost rapid workflow for accurately quantifying geomorphological changes aftermath a natural disaster. We used unmanned aerial vehicle (UAV) surveys collect imagery 44...
Abstract Landslides occur where the stresses below surface exceed shear strength of material. Landslide inventories thus offer opportunities to investigate patterns in subsurface provided that stress conditions at failure can be estimated. Clues are encoded inclination slope failed and thickness sliding mass. We use this insight develop a two‐dimensional (2D) landslide back‐analysis model estimates bedrock over broad scales relevant earthquake‐triggered hazard landscape evolution. A unique...