Publications

Wilshire Grand Project, Los Angeles, California. Project Manager and Principal Engineer (Geotechnical Engineer of Record)

Managed and served as principal engineer for geotechnical, environmental, and seismic engineering, and geotechnical and environmental inspection for the $1.3 Billion project in downtown Los Angeles. The excavation for the project extends to 106 feet below grade, and comes to within about 7 feet of the existing Metro Red Line Subway Tunnel. A two-dimensional finite difference analysis was performed to evaluate the impact of the excavation and the building construction on the structural performance of the tunnel, as well as operations of the trains through the tunnel. An extensive tunnel instrumentation monitoring program was undertaken to evaluate movement, using Automated Total Station devices installed within the tunnel to monitor movements to within 1 millimeter. Monitoring also included vibration monitoring within the tunnel, and manual surveys and measurements including tunnel convergence measurements. Monitoring on the shoring included manual surveys, slope inclinometers, tie-back load cells, and raker brace stress monitoring, all tied into an automated monitoring network.

Next Century Project, Los Angeles, California. Project Manager and Principal Engineer (Geotechnical Engineer of Record)

Managed and served as principal engineer for geotechnical and seismic engineering for the $2.5 Billion Next Century project in Century City. The twin towers are 46 stories tall, are supported on mat foundations, and were constructed around the pre-existing Century Plaza Hotel, which was also rehabilitated and repurposed as part of the project. Innovated combinations of mat foundations and pile foundations allowed for top-down construction to be performed in a portion of the site to allow an existing driveway to an adjacent property to remain in operation while constructing subterranean levels beneath the roadway surface. The seismic services included preparing ground motion studies consisting of development of response spectra and acceleration time-histories for performance-based design of the towers. Also managed a methane investigation and methane design for the project, which required use of the highest level of methane protection based on methane levels measured at the site. Finally, managed a monitoring system for the existing Century Plaza Hotel, for the shoring system, and for adjacent properties using Automated Total Station technology such that the construction could be monitored for real-time movements and loads to verify construction did not results in excessive movements.

Landmark II High-Rise Development, Los Angeles, California. Project Manager and Principal Engineer for Geotechnical Engineering (Geotechnical Engineer of Record)

Provided geotechnical and seismic engineering, and geotechnical inspection for the 35-story residential high-rise project with four levels below grade. The new structure was constructed within an existing subterranean parking structure that serves an existing office high-rise building on the site. Groundwater in the surrounding area is higher than the basement, and the building provides continuous permanent dewatering to lower the local groundwater to just below the basement slab elevation. The challenge was to construct the new high-rise within the existing subterranean parking garage without impacting the existing remainder of the parking garage nor the office high-rise, which remained occupied and operational during the construction of the residential high-rise. New drilled pile foundations were constructed below the basement to support the new residential tower, requiring construction of the piles with the groundwater level remaining at the level of the pile caps.

Ronald Reagan/UCLA, Westwood Replacement Hospital, Los Angeles, California. Project Manager.

Provided geotechnical and seismic engineering, and geotechnical inspection for the Westwood Replacement Hospital, the largest single building project in the history of the University of California system. The building is located on a site that is within a state-designated liquefaction hazard zone. Although adjacent buildings had been supported on costly driven pile foundations, through the detailed analysis of the conditions at the site, the new hospital building was able to be supported on a mat foundation. This detailed evaluation of foundation conditions and liquefaction thus allowed very large foundation savings by avoiding the use of deep foundations or ground improvement, and avoided the noise of pile driving in a university environment.

Saint John’s Hospital and Health Center Replacement Project, Santa Monica. Project Manager.

Provided geotechnical and seismic engineering, and geotechnical inspection services during construction for the replacement of the hospital buildings and associated medical office buildings. The hospital building is entirely base-isolated.

Community Memorial Hospital New Medical Building and Cabrillo Radiation Oncology Center Addition Geotechnical Services, Ventura, California.

Principal Engineer for project which involved the construction of a replacement hospital building. Responsible for foundation recommendations, which included the use of ground improvement technique of soil mixing. This project was the first project using soil mixing to mitigate liquefaction for a hospital in California. Scope: Geotechnical investigation for construction of proposed six-story, 320,000-SF hospital facility to replace existing medical facility, and construction of addition of radiation oncology facility. Hospital includes 242 beds, a 33-bed emergency room and two additional operating rooms. The $200 million project updates the hospital's brick and mortar facilities and meets revised state seismic safety standards. Services included subsurface explorations, laboratory testing, engineering analyses and recommendations, follow-up supplemental consultation services, geotechnical inspection and testing, and installation of seismic instrumentation in new building.

UCLA Luskin Conference and Guest Center, Los Angeles, California. Principal Engineer.

Provided geotechnical engineering recommendations for the design of the foundations, excavation and slopes, shoring, ground motion studies, and geologic-seismic hazards. By careful evaluation and use of original data for former parking structure at the site, was able to show that the site was not liquefiable and could be supported on shallow foundations.

University of California at Los Angeles Royce Hall Historical Building Earthquake Repair and Design, University of California Los Angeles, Los Angeles, CA, Project Engineer.

Responsible for performing ground motion study to develop response spectra used in seismic analysis. Wrote letter presenting results of ground motion study. Assisted with structural damage assessment, provided geotechnical recommendations, and developed design basis earthquake model for UCLA's historic Royce Hall after it sustained severe structural damage in the 1994 Northridge earthquake.

City of Los Angeles Department of Water and Power - Upper Stone Canyon Reservoir Seismic Evaluation, Los Angeles.

Principal Engineer providing seismic evaluation of existing dam and surrounding reservoir slopes. Provided ground motions studies including development of response spectra and earthquake time-histories matched to the spectra. Performed seismic evaluation of the dam using FLAC, with input consisting of the ground motions developed. The seismic evaluation was used in evaluating the shaking response and the deformation characteristics in the design event. The seismic evaluation was performed using geotechnical data obtained through the geologic and geotechnical explorations and testing of the dam under the management of Dr. Hudson.

City of Los Angeles Department of Water and Power - Headworks Reservoir (Silverlake Reservoir Replacement Project), Los Angeles, California.

Project Manager for geotechnical engineering and Bituminous Geomembrane installation inspection for new 110-million gallon reservoir at site adjacent to Los Angeles River. New concrete reservoir is one of the world’s largest concrete box reservoirs. Challenges included potential liquefaction at site. Explorations included unusual and specialty testing, including Becker Hammer testing, Sonic Core borings, and shear wave velocity profiles from OYO-suspension logging and Spectral Analysis of Surface Wave (SASW) testing for use in ground motion studies. Work included ground motion studies and spectral matching of recommended response spectrum using seed time histories. Performed site response analysis and Soil Structure Interaction analyses using SHAKE91, QUAD4M, and FLAC. Performed liquefaction analysis using the results of Becker Penetration Test (BPT) borings and conventional SPT borings. Performed one of the first-ever uses of the instrumented Becker Penetration Test (iBPT) equipment for evaluating the density of the gravelly soils beneath the site.

Photo of Team in front of Tunnel Boring Machine

Metro Purple Line Subway Extension, Los Angeles County Metropolitan Transportation Authority, Los Angeles, California

Project Manager. Performed the geotechnical and environmental investigation associated with development of the Draft EIR/EIS for the project and Advanced Conceptual Engineering. Geotechnical and environmental field work included investigation of methane gas and hydrogen sulfide gas, especially in the vicinity of the La Brea Tar Pits. Performed specialty testing the borings, including in-situ pressuremeter testing in soil and rock deposits to evaluate in-situ at-rest lateral earth pressure coefficient. Provided lateral earth pressure recommendations for shoring, below-grade walls and tunnel lining. Performed ground motion studies for several sites along the Los Angeles metro network system to develop the seismic design criteria for future Metro Seismic Design Criteria. Performed seismic analyses at stations, including development of postulated earthquake time histories and two-dimensional dynamic evaluation of seismic wave propagation at the Wilshire/Fairfax station using QUAD4M, which Dr. Hudson wrote as part of his Ph.D. program. Developed and installed instrumentation program for a test shaft excavation for the project for the proposed Wilshire/Fairfax station, including manual Slope Inclinometers, SAA automated slope inclinometers, installation of wells for monitoring of groundwater and gas, including utilizing vibrating-wire pore pressure measurement, and remote transmission of data. Performed fault investigations at the crossing of potential subway alignments at the Santa Monica Fault and Newport-Inglewood Fault, including dozens of borings, Cone Penetration Tests, and an extensive geophysical program.

Metro Regional Connector, Los Angeles County Metropolitan Transportation Authority, Los Angeles, California.

Project Manager. Performed the geotechnical and environmental investigation associated with development of the Draft EIR/EIS for the project, Advanced Conceptual Engineering, Preliminary Engineering, and Advanced Preliminary Engineering. Geotechnical Investigation included review of hundreds of our prior borings along proposed subway alignment, and performing additional borings to fill-in gaps in prior data. Performed borings from which vibration analyses were performed for the Walt Disney Concert Hall. Performed two-dimensional analysis of station excavation at 2nd/Hope Street to evaluate lateral earth pressure. Performed seismic analyses at stations. Performed evaluation of alignment crossing of postulated Coyote Pass Escarpment in the Little Tokyo district of Los Angeles, utilizing borings and geophysics.

West Hollywood Edition Hotel, 9040 Sunset LLC, West Hollywood, CA, United States.

Principal Engineer and Project Manager for geotechnical investigation for $300 Million mid-rise two-tower (13 and 9 story) hotel development. Provided recommendations that allowed use of spread footing foundations although loads for the 190-room luxury project, saving considerable money on foundations for the project.

Montage Resort (Treasure Island Redevelopment Project), Laguna Beach, California.

Principal Engineer and Project Manager for the geotechnical investigation for a new major hotel and residential development. Project included major site grading, and specialized consultation regarding ocean-bluff analyses, stabilization, and rehabilitation recommendations. Soil Nailing was performed to retain Coast Highway for the excavation for the hotel, and was approved by Caltrans. Reviewing agencies included City of Laguna Beach and California Coastal Commission, with the California Coastal Commission reviewing in detail the proposed slope stabilization design.