G. Thomas Dunlap, P.E., R.P.G.
University of Mississippi, M.S., 1990 – Civil Engineer
University of Mississippi, B.S., 1989 – Civil Engineer
University of Mississippi, B.S., 1988 – Geology
Professional Engineer: Mississippi, Missouri, Tennessee
Professional Geologist: Missouri
American Society of Civil Engineers (ASC)
National Society of Professional Engineers (NSPE)
Association of Engineering Geologists (AEG)
American Railway Engineering & Maintenance of Way Association (AREMWA)
Burns Cooley Dennis, Inc., Principal, _____ to Present
Burns Cooley Dennis, Inc., Senior Geotechnical Engineer, Geologist, October 1994 – Present
Burns & McDonnell Engineering Company, Inc., Geotechnical and Environmental Engineer, January 1991 – October 1994
Background. Mr. Dunlap has worked on a variety of projects in geotechnical engineering for over 25 years. These projects include roadways, railway bridges, aviation facilities, wastewater and water treatment facilities, dams, river levees, amusement parks, power plants, electricity substations and transmission lines, commercial and industrial facilities. He has a wide range of general geotechnical experience over geographical regions throughout the United States and in areas outside the U.S. such as Mexico, Central America, the Middle East and Spain.
Experience. Aspects of geotechnical engineering that Mr. Dunlap has been responsible for include supervising and coordinating subsurface, groundwater and borrow site investigations and special instrumentation studies, geotechnical data evaluation and design, preparation of geotechnical reports and specifications, and foundation and earthwork testing and inspection. He takes advantage of his geology educational background in all projects by relating geology aspects of a site to geotechnical engineering design issues and has personally conducted subsurface and groundwater field investigations. Other specific geotechnical related knowledge that Mr. Dunlap possesses is with rock excavation and mining, tunneling, braced excavations, sheeting and shoring, geophysical studies, basic dewatering and groundwater studies, and soil modification studies.
Industrial/Manufacturing. Mr. Dunlap has considerable experience as project manager and primary geotechnical design engineer and geologist on numerous industrial and manufacturing buildings of various sizes and types. Buildings he has provided geotechnical evaluation and recommendations on have included large single-level and multi-level structures. Mr. Dunlap has provided geotechnical recommendations for a variety of foundation types and special earthwork to address a variety of subgrade soil conditions. Foundation types have included slab-on-grade, monolithic slab and grade beam, conventional foundations, strip and spot footing foundation systems with a separate slab-on-grade, drilled shaft foundations, bell-bottom pier foundations, auger cast piling foundations, driven concrete and/or steel piling foundations, etc. He has addressed various soil conditions including expansive soils, weak and compressible soils, rock and corrosive soils with regard to foundation design and special earthwork requirements. Representative projects have included Generating Station in Haywood County, Tennessee, Nissan manufacturing plant in Canton, Mississippi; Moselle Generating Station in Jones County, Mississippi; Catapote in Flowood, Mississippi; Koch Foods in Morton, Mississippi; Tyson Processing in Canton, Mississippi; and Automotive Megasite, Schulz Tube Mill, and GreenTech Automotive in Tunica County, Mississippi.
Buildings. Mr. Dunlap has considerable experience as project manager and primary geotechnical design engineer on numerous commercial, public and private buildings of various sizes and types. Buildings he has provided geotechnical evaluation and recommendations on have included large residential homes, churches, single-story and multi-story motels, apartment complexes, small office buildings, multi-story office buildings and government buildings, manufacturing and industrial buildings and warehouses, large retail buildings and shopping malls, casino buildings, schools, assisted living and retirement homes, hospitals, etc. Mr. Dunlap has provided geotechnical recommendations for a variety of foundation types and special earthwork to address a variety of subgrade soil conditions. Foundation types have included slab-on-grade, monolithic slab and grade beam, conventional foundations, strip and spot footing foundation systems with a separate slab-on-grade, drilled shaft foundations, bell-bottom pier foundations, auger cast piling foundations, driven concrete and/or steel piling foundations etc. He has addressed various soil conditions including expansive soils, weak and compressible soils, rock and corrosive soils with regard to foundation design and special earthwork requirements.
Seismic. Mr. Dunlap has evaluated various seismic design issues on a variety of projects as part of the geotechnical investigation. These issues include determination of site design acceleration coefficients from the Standard Building Code (SBC) in some past cases and currently the International Building Code (IBC), and other related code versions. Mr. Dunlap has a knowledge of the probability based maps such as those through the USGS by Algermissen, liquefaction potential analysis using computer program LIQUIFY2 and from evaluation utilizing USGS Open-File Report 85-457 “Estimation of Earthquake Effects Associated with Large Earthquakes in the New Madrid Seismic Zone”, evaluation of liquefaction effects and horizontal acceleration derived forces on deep foundation piling and piers, retaining/subgrade walls, various slopes/embankments, and landfills. He has assisted structural engineers on seismic design issues considering the more recent methodology, Normalized Response Spectra, which considers serviceability, ultimate load and surviveability, similar to the methodology presented in AREMA’s “Seismic Design for Railway Structures.” He has provided seismic design for various projects in and around the New Madrid Fault Zone and other seismically active areas including power plant and levee embankment projects in southeast Missouri and west Tennessee, highway bridge projects in northwest Mississippi, water tank and substation projects in north Mississippi and building and embankment projects in Alabama.
Bridges/Roadways. Mr. Dunlap has provided geotechnical engineering, project planning and management, and/or geologic evaluation on a number of highway and roadway projects. These projects have included road centerline profile and bridges. Subsurface soil conditions at the bridge sites were explored by means of soil borings typically to 70-100 ft. The geology and groundwater conditions are determined. For roadway alignments, the centerline soil profile was developed to determine the soil types available for borrow and the appropriate CBR for pavement design. Laboratory testing included compression tests, classification tests, unconfined compression tests, triaxial compression tests and consolidation tests. Recommendations were developed for various deep foundations including driven H-pile, prestressed concrete pile and drilled shaft foundations. Analyses were performed to evaluate the settlement and stability of approach embankments. When projects are in relatively close proximity to the New Madrid fault complex, seismic site characterization was considered in the analyses. The geotechnical analyses and site characterization employ standard transportation department design methodology. Example projects have included State Route 57 over Norfolk Southern Railay Line in Rossville, Tennessee, several bridge replacements in Tipton County, Tennessee; nine bridges and centerline profile for a segment of the I-269/Hwy 304 corridor in DeSoto County, Mississippi; three bridges and roadway centerline for improvements to the Holly Springs Road in DeSoto County, Mississippi; planning stages for I-40/SR-196 Interchange bridge and frontage road centerline in Fayette County, Tennessee; bridge replacement for North Watkins over Cypress Creek in Shelby County, Tennessee; SR 4 in Tate County, Mississippi; SR 5 bridges and road centerline near Cockrum, Mississippi; Stateline Road and Hacks Crossing Road Improvements-Shelby County, Tennessee/DeSoto County, Mississippi; new road to service Baptist Hospital for Mississippi State Aid funded project in Southaven, Mississippi; and two bridges and 2 miles of centerline for Wolf River Boulevard in Germantown, Tennessee.
Deep Foundations. Mr. Dunlap has performed or coordinated design and quality assurance for various types of deep foundations for a variety of clients. Design aspects typically involve the set up of geotechnical investigation, evaluation of soil/rock data, evaluation of compression and uplift capacity of deep foundation elements utilizing various hand and computer oriented analyses, evaluation of any lateral and/or moment loading on the deep foundations generally using the finite difference computer analysis program COM624, evaluate internal stresses and loading for concrete drilled shafts or piling to establish needed steel placement and cap tie-ins, evaluate drivability and stresses of driven piling utilizing the Wave Equation Analysis Program (WEAP), set up and evaluate results of load testing including Osterberg load-cell and other deep foundation testing such as Pile Driving Analyzer (PDA) or auger cast pile sonic logging where warranted. Economic optimization of deep foundation type, size and length is of paramount importance while performing these design items. Typical projects have included driven concrete piles and drilled shafts to support nine bridges for State Route 304 and Interstate 55 in Desoto County, Mississippi for the Department of Transportation, pile foundations and embankment in river alluvium for south approach abutment and rock-socketed drilled shafts for north abutment for 63rd Street Bridge replacement project in Kansas City, Missouri; auger cast pile design and load testing for Hollywood Casino in Shreveport, Louisiana and hotel addition to the Silver Star Casino in Philadelphia, Mississippi; wood pole compression, uplift, and lateral load testing and screw anchor load testing for a H-frame supported transmission line through the Mayan Mountains and coastal swamps in Belize, Central America; drilled shafts in limestone and shale and PDA tested steel H-piles with points of various structures at the Thomas Hill, Missouri Power Plant for Associated Electric Cooperative; drilled shafts and H-piles in a bridge replacement for the City of Kansas City, Missouri where downdrag was an issue; precast-prestressed concrete piles for a fuel farm at the Washington National Airport where driveability, stresses, and capacities were evaluated using the WEAP, PDA testing, and static load testing; drilled shafts through construction waste with embedment into shale for a water ride at Worlds of Fun Amusement Park in Kansas City, Missouri; drilled shafts for a jib-crane at the Arizona Electric Power Cooperative in Cochise, Arizona; drilled shafts for a microwave tower in Columbia, Mississippi for the south Mississippi Electric Power Association; drilled shafts in problem soil and rock conditions requiring special design and construction for transmission lines in Kansas for the Kansas Board of Public Utilities and in Texas for Southwest Power Cooperative; steel H-piles for combustion turbine machine foundation with dynamic loading at the Undalusa Power Plant in Alabama for the Alabama Electric Cooperative; evaluate the alternatives of prestressed concrete piles, auger cast piles, steel H-piles, and drilled shafts to support a metal plating shop in Keyport, Washington for the U.S. Navy; steel H-piles for Bristol-Meyer Squibb’s hanger at Mercer County Airport, New Jersey; auger cast piles considering liquefaction for fuel oil and chemical tank storage facility for the Kansas City, Missouri Water & Pollution Control Department; auger cast piles at the New Madrid, Missouri Power Plant for Associated Electric Cooperative.
Pavements. Mr. Dunlap has provided geotechnical expertise on various pavement related projects. He evaluated existing subgrade conditions using a field dynamic cone penetrometer (DCP) and existing pavement from cores for the Lake Harbour Drive and County Line Road improvement project in Jackson, Mississippi. He provided geotechnical expertise for an airfield pavement project in Fayette County, Tennessee. He investigated the existing soil and rock conditions for a centerline profile for street improvements for a section of 127th Street in Overland Park, Kansas. He investigated deteriorated taxiway and apron pavement for the National Guard Bureau in St. Joseph, Missouri, making recommendations on needed subgrade and drainage improvements; performed a thorough geotechnical study of the runway pavement subgrade at Johnson County Executive Airport in Kansas; conducted a night-time pavement subgrade and contaminated soil study and evaluated a potential borrow source needed for apron pavement replacement at the Kansas City International Airport in Missouri.