A.J. McGinn
Dr. McGinn leads one of the largest firms that specializes in the design and construction of tunnels for water, wastewater, transportation, and other infrastructure. For more than 25 years, he has designed cut-and-cover excavations; conventionally mined tunnels in soil and rock; and earth pressure balanced and slurry tunnels in urban and sensitive environments. His experience also includes design and implementation of subsurface exploration programs, including soil and rock laboratory testing programs, to establish in situ strength and deformation characteristics for geotechnical design.
Dr. McGinn is a specialist in developing, executing, and interpreting numerical simulations for design complex geotechnical systems. He has served as a guest lecturer at Cornell University in the areas of excavation support design, rock mechanics, shallow and deep foundation design, and advanced soil behavior.
Relevant Projects
Bertha TBM Access Shaft, Alaskan Way WR99, Seattle, WA
Project Manager, QA/QC Review & Design and Construction Documents
When complete, this dual stacked freeway within the SR 99 tunnel constructed by the largest ever Earth-Pressure-Balance tunnel boring machine (TBM), will carry over 80,000 vehicles each day. During early December 2013, obstructions and mechanical issues halted tunneling. Brierley Associates was retained by Seattle Tunnel Partners, the design-build joint venture, to design an access shaft that allowed removal of the cutter head assembly from the TBM nicknamed “Bertha”. Dr. McGinn provided QA/QC of design and construction documents for the approximately 116-ft deep by 80-ft inside diameter secant pile supported shaft and a mass-concrete cradle at the bottom of the shaft to receive the TBM. Secant pile diameters varied between 1.0m and 3.0m. Components of design also included jet grout cutoff walls, dewatering and depressurization under the shaft base and around the 57.5-ft diameter TBM penetration and geotechnical instrumentation. This is the deepest application of secant piles in North America. The prior record was set at the New Irvington Tunnel Vargas Shaft, also designed by Brierley.
Lake Mead Intake No. 3 (IPS-3), Las Vegas, NV
The Lake Mead Intake No. 3 project includes five major components: a deep-water intake riser and inlet structure; an intake tunnel driven beneath the lake and a portion of Saddle Island; a pumping station on Saddle Island; a discharge pipeline connection to the Alfred Merritt Smith Water Treatment Facility; and a tunnel connecting the IPS-3 facilities with the existing IPS-2. IPS-3’s basic concept is to draw water from below the lake’s thermocline, providing reliable access to better water quality (minimizing the need for additional treatment processes). Vegas Tunnel Constructors (VTC), a joint venture of Impregilo SpA and SA Healy, was awarded SNWA Contract for IPS-3 – Shafts and Tunnel. Brierley Associates and our client ARUP were retained by VTC to provide the detailed design for the contract. Brierley provided shaft design engineer, starter tunnel design, geotechnical characterization, and specification and submittal review. Main areas of work included a 30-ft diameter, 600-ft deep tunnel access shaft; a TBM-excavated, 20-ft diameter, 3-mile-long intake tunnel beneath the lake; an intake structure in the lake consisting of a caisson structure that was fabricated on the lake surface, immersed into a preformed excavation, and encased in tremie concrete. The intake structure served as a dock to receive the TBM. Dr. McGinn served as Shaft Design Engineer.
Shaft Design Engineer
Circular Concrete Secant Pile Wall, South Cobb Pump Station, Cobb County, GA
Lead Shaft Design Engineer
Dr. McGinn led the design team for temporary excavation support system through residual soil and weathered rock in which a pump station shaft was constructed by Hayward Baker, Inc. A 130-ft diameter concrete secant pile wall with reinforced concrete and steel ring beams was designed to retain a 15- to 48-ft thick layer of soil and transition zone material (residual soil and weathered rock) to allow excavation to a depth of over 200-ft below ground surface. Steel beams were inserted into every fourth secant pile, and intermediate piles were offset to arch between primary piles. Due to highly irregular rock surface around the shaft perimeter, up to two rows at ground anchors were used to stabilize the bottom of the secant pile wall system as the excavation advanced into rock.
Ohio Canal Interceptor Tunnel (OCIT), City of Akron, Akron, OH
Principal-in-Charge
The Ohio Canal Interceptor Tunnel (OCIT) project consists of an approximately 6,200-ft long 27-ft inside diameter main conveyance and storage tunnel with a precast segmental liner and constructed utilizing an earth pressure balance (EPB) tunnel boring machine (TBM) in variable ground conditions consisting of soft ground, mixed face of soft ground over bedrock and bedrock. In addition to the tunnel, the project includes near surface structures (NSS) consisting of tunnel diversion structures (TDS) and four drop shafts that range in internal diameter from 18- to 45-ft and depths of 70- to 150-feet. Brierley Associates was retained by the project General Contractor, Kenny/Obayashi a Joint Venture to service as the Contractor’s Engineer for the scope of work described above.
Cornell Linear Accelerator Tunnel LINAC Facility, Cornell University, Ithaca, NY
Geotechnical Engineer
Brierley Associates assisted Cornell University and its design consultants in planning for construction of a new beam detection hall and laboratory facility connected to a 3,175-ft long by 14-ft diameter tunnel to expand Cornell’s high energy physics facility to keep Cornell at the leading edge of high-energy physics in the United States. Work included a detailed subsurface investigation program to characterize soil, rock and ground water conditions at the site along with engineering evaluations for the tunnel construction, a new laboratory facility and subterranean connections to an existing accelerator tunnel. Performed geotechnical evaluation of ground characteristics, settlement analysis and assisted with preparation of the Geotechnical Data Report and Geotechnical Investigation Report.
Northeast Boundary Tunnel, District of Columbia
Principal-in-Charge and Site/Task Leader
Principal-in-Charge and Site/Task Leader for this Design/Build project with Salini-Impregilo-Healy JV. This 23-ft (7m) inside diameter tunnel is approximately 27,000-ft (8.2km) and ranges in depth from about 60- to 140-feet (18.2m to 42.6m). The alignment passes beneath a portion of the RFK Stadium parking lot, Langston Golf Course, National Arboretum, Mount Olivet Cemetery, New York Avenue, Amtrak Rail Yard, and a large section of Rhode Island Avenue. The project includes seven shafts ranging in depth from 77-ft (23.5m) to 155-ft (47.2m) with diameters varying from about 19.5 to 56-feet (5.9m to 17m). Associated with each shaft are near surface diversion and conveyance structures. The tunnel envelope will be within the Potomac Group soils consisting of clays, sandy soils and possibly mixed face conditions, such as a layer or layers of impermeable materials in combination with a layer or layers of water-bearing clean sands and gravels under pressurized conditions. Given the ground conditions, a Herrenknecht EPB-TBM has been selected to mine the tunnel.
Waukesha Greenmeadow Interceptor, Waukesha, WI
Principal-in-Charge
Principal-in-Charge for design of a gravity interceptor sewer project from Greenmeadow Pump station to Waukesha’s Waste Water Treatment Facility, which includes multiple soil and rock shafts, approximately 2,600-LF of 84-in TBM rock tunnel for a 42-in pipe, and 1,300-LF of twin 30-in horizontal directional drills in soil to cross beneath the Fox River. Brierley is serving as specialty geotechnical/geostructural/tunnel and trenchless design subconsultant. Brierley is responsible for planning and execution of the geotechnical investigation, in-situ, and laboratory testing, writing of the Geotechnical Data and Baseline Reports, and design efforts for the underground tunnel and HDD designs for which Brierley was responsible. Brierley is also involved during the construction, which began in 2018 and in designer review of submittals and field verification of the design for the client, as well as assisting the client in claims support.
NovA Near Detector at Fermi Nuclear Physics Lab, Batavia, IL
Principal-in-Charge & Geotechnical Instrumentation Reviewer
Brierley Associates, in the role as the contractor’s designer, completed pre-bid analysis of ground conditions and anticipated behavior for the excavation of the 350-ft deep NDH and ancillary passageways. Dimensions of the main chamber are 20-ft wide by 22-ft high and 75-ft long. Additionally, 2D and 3D finite element modeling was performed by Brierley to evaluate the induced stresses in the rock pillar under different construction and support scenarios. Based on these studies, an alternative design and construction approach was proposed by Brierley and accepted. The alternative approach consisting of the installation of pre-stressed rock bolts through the pillar prior to implementing sequential excavation work saved significant monies for Fermi.
New Irvington Tunnel, Sunol to Fremont, San Francisco Bay Area, Fremont, CA
Design Consultant
New Irvington Tunnel (NIT) is a critical redundancy component of the Hetch Hetchy water system that is operated by the San Francisco Public Utilities Commission and provides drinking water to San Francisco. Located east of Fremont, the project involves the construction of a new tunnel, connections to existing facilities at each end of the new and existing tunnels, and the other ancillary facilities. Almost 3.6 miles long, the NIT is roughly parallel the 80-year-old Existing Irvington Tunnel (EIT). The NIT is 12-ft wide by 14-ft high modified horseshoe-shaped tunnel excavated primarily by roadheader. Also drill-and-blast and hand mining techniques with the latter implementing sequential excavation of top heading and bench with breasting and spiling in the worst ground conditions, have been deployed. Brierley Associates served as the Contractor’s Engineer during construction. Services provided include: pre-bid evaluations and bid preparation assistance; design and submittal preparation for tunnel excavation and initial support and dewatering; full time on-site mapping for determination of Ground Class and Support Category selection during tunneling; documentation of actual ground conditions with respect to those conditions presented in the Geotechnical Baseline Report. Dr. McGinn served as Design Consultant.
Caldecott 4th Bore Tunnel, Almeda and Contra Costa Counties, CA
Design Consultant
Top U.S. Road Project of 2013 - Roads & Bridges Magazine
2015 Excellence in Transportation Award - Caltrans
2014 Project of the Year Award - California Transportation Foundation
The Caldecott Fourth Bore Tunnel is an approximately 3,250-ft long by 49-ft wide by 40-ft high two-lane highway tunnel built through the East Berkeley Hills to improve traffic conditions on congested SH 24 connecting Alameda and Contra Costa counties. The tunnel, constructed by the Sequential Excavation Method (SEM) or New Austrian Tunneling Method (NATM), also includes seven mined cross passages that connect the in-service third and fourth bores and serve as emergency exits. Dr. McGinn served as Design Consultant.
North MacGregor Storm Sewer Relief Project, Houston, TX
Shaft Engineer
Texas CEC Engineer’s Excellence Award - 2010
The City of Houston’s Storm Water Management Program (SWMP) implemented this project subsequent to the flooding caused by Tropical Storm Allison. The completed project afforded flood hazard reduction to the Texas Medical Center, Rice University, Hermann Park, and surrounding areas. Approximately 3,340-ft of 15-ft excavated diameter storm sewer tunnel was constructed with a closed face, Earth Pressure Balance Machine. This technology allowed tunneling to proceed without active dewatering along the tunnel alignment from the ground surface. Concurrent with mining, pre-cast, bolted, and gasketed concrete segments were installed which resulted in a 12-ft diameter finished stormwater conveyance. The was the first project where an EPB machine was used with one pass, pre-cast concrete segments in the City of Houston and the surrounding metropolitan area.
Laurel Line (Crown Ave) Tunnel, Scranton, PA
Tunnel Mapping and Design Team Member
This 4,750-ft. long, horseshoe-shape tunnel was mined using drill and blast technology and placed into service in 1905. From 1905 until the 1950s the tunnel serviced the Laurel Line that provided passenger service between Scranton and Wilkes-Barre, Pennsylvania. Brierley Associates was retained by local civil engineering firm to inspect and map the both the lined and unlined sections of the tunnel relative to condition of exposed timber; rock and concrete defects; groundwater inflow; and evidence of rock displacement. Subsequently specifications for tunnel rock reinforcement and shotcrete operations were developed and incorporated into the contract documents, prepared by others, to rehabilitate the tunnel. During execution of tunnel improvements, Brierley reviewed contractor submittals and provided technical support. Dr. McGinn served as a member of the tunnel mapping and design team.
North and South Sacramento River Crossings, Sacramento, CA
Geotechnical and Shaft Design Engineer
Brierley Associates designed approximately 28,000-ft2 of retained earth for construction of launching and receiving shafts for the Sacramento River Crossings project. The 154-ft long by 39-ft wide by 30-ft deep launching shafts were supported by a combination of one level of pipe struts and a deadman wall. The deadman provide a 50-ft long clear opening in the middle of the shaft to facilitate installation of 40-ft long sections of reinforced concrete pipe that will be placed in the tunnels. The 50-ft long by 25‑ft wide by 47-ft deep receiving shafts were supported by one and three levels of corner struts. A 5‑ft thick reinforced concrete slab was designed to resist the specified maximum baseline uplift pressures associated with the 100-year flood level stage of the Sacramento River at the north receiving shaft, which was constructed in-the-dry. At the south shaft which was constructed in the wet, a 10-ft thick unreinforced concrete tremie slab was designed to resist baseline pressures
Automated People Mover Tunnel System, Dulles International Airport, Fairfax County, VA
Project Geotechnical Engineer and Support-of-Excavation Designer
As part of the D2 Expansion Program, the Metropolitan Washington Airports Authority designed an Automated People Mover (APM) System to replace the fleet of "mobile lounge" surface transportation system. The new system includes over ten miles of APM, tug, baggage conveyor, utility, and walkback tunnels and a vehicle maintenance facility. The Design Team consisting of three tunnel design firms was managed by the prime designer, HNTB Corporation, with Brierley Associates serving as Geotechncial Discipline Manager. Responsibilities of overall discipline management included: planning and execution of subsurface investigations, Geotechnical Data Report and Geotechnical Baseline Report preparation, geotechnical design for three of four tunnel design packages and geotechnical subcontract administration. Brierley Associates also designed and managed the implementation of the subsurface exploration program, including soil and rock laboratory testing, to establish in situ strength and deformation characteristics for geotechnical design. Also designed soil nail wall and rock anchor support systems for cut-and-cover tunnel construction.
Twin Box Tunnels - Liberty University, Lynchburg, VA
Principal-in-Charge
ENR Mid-Atlantic Region Best Small Project 2014
ENR Mid-Atlantic Region Best Project Safety Award 2014
ACEC Virginia-Grand Award 2014
Dr. McGinn served as Principal-in-Charge for design and construction of this jacked box-tunnel. The project consists of two, two-lane, 130-ft long vehicular tunnels that were installed by a unique “pulling operation” beneath three Norfolk Southern railway lines where up to 32 trains including AMTRAK pass through each day. The two vehicular tunnels now provide much needed access to Liberty University from Ward Road at the intersection with Harvard Street. Elements of this project include: installation of temporary excavation support systems to excavate the launching and receiving areas; installation of geotechnical instrumentation to monitor ground deformations; installation of spiling to control ground loss at the heading and mitigate deformation of the railways; installation of conduits through the embankment to protect post-tensioning tendons to facilitate the jacking operation; construction of a reinforced concrete launching pad; construction of a reaction block and a stable working surface at the receiving area; on-site construction of the concrete tunnel boxes, including a cutting shield, at the launching area; and pulling the two tunnel boxes to the final location.
Box Tunnel beneath CSXT/Norfolk Southern Railroad
Lynx Blue Line Extension-Northeast Corridor LRRT, Charlotte, NC
Engineer-of-Record
This 12-ft by 10-ft by 110-ft long reinforced concrete box culvert jacked through an existing CSXT/Norfolk Southern rail embankment posed several challenges. One challenge was the need to relocate an existing 60-in diameter sewer line that conflicted with the proposed jacking pit. Another challenge that the team contended with was the geometry and composition of the rail embankment combined with shallow depth of cover amounting to 19-ft, between the top of the new box tunnel and the rail line. Given the conditions and the potential for ground movement during jacking of the new tunnel, pre-grouting prior to tunneling and spiling were installed.
Washington Road Underpass, Augusta, GA
Principal-in-Charge and Engineer-of-Record
The project required design of a 120-ft long vehicular underpass below an arterial road with Average Annual Daily Traffic of nearly 35,000 vehicles. A jacked box tunnel was chosen to minimize disruption and eliminate road closures during construction of the underpass. The box tunnel with a clear height of 16-ft and a clear width of 26-ft is cast-in-place concrete with structural steel shield built on site on a launch slab and jacked under the road utilizing steel strands and post-tensioning jacks while the heading is mined. A reaction wall on the receiving end utilizes soil weight to resisting the jacking forces. The approaches to the underpass are cuts utilizing soil nail walls to provide top-down construction of the temporary support of excavation for construction. Other components of construction include geotechnical instrumentation for monitoring ground deformations, pipe spiling to control ground loss at the heading and mitigate settlement of the road above and installation of tendon ducts.
Principal-in-Charge
The project required design of a 401-ft long pedestrian and vehicular underpass below an arterial road with Average Annual Daily Traffic of over 24,000 vehicles. A jacked box tunnel was chosen to minimize disruption and eliminate road closures during construction of the underpass. The box tunnel with a length of 168-ft, clear height of 15-ft and a clear width of 20-ft is cast-in-place concrete with structural steel shield built on site on a launch slab. It will be jacked under the road utilizing steel stranded tendons and post-tensioning jacks while the heading is mined. A reaction wall on the receiving end will utilize lateral earth pressures to resisting the jacking forces. Once the middle portion is jacked in place, the remainder of the underpass will be constructed as cut-and-cover tunnels at each end with lengths of 86-ft and 147-ft. The approaches to the underpass will be sloped cuts to portal walls consisting of soil nail walls and MSE walls with permanent cast-in-place concrete facings. Other components of construction include geotechnical instrumentation for monitoring ground deformations, pipe spiling to control ground loss at the heading and mitigate settlement of the road above and installation of ducts for the jacking tendons.
Publications
- “Lessons Learned for Ground Movements and Soil Stabilization from the Boston Central Artery”,(2006), with O’Rourke,T.D. , Vol. 132, Issue 8 (August) ASCE Journal of Geotechnical and Geoenvironmental Engineering,
- “Lessons Learned for Ground Movements and Soil Stabilization from the Boston Central Artery”, 2005 Peck Lecture Paper, with O’Rourke,T.D.
- “Case Study of Excavation Base Stability in Deep Marine Clay”, (2003) with O’Rourke, T.D. Performance Confirmation of Constructed Geotechnical Facilities (GSP 94), Eds. Lutenegger, A.J. and DeGroot, ASCE, Reston, VA.
- "Performance of Deep Mixing Methods at Fort Point Channel", with O'Rourke, T.D., (2003), prepared for Bechtel/Parsons Brinkerhoff, Massachusetts Highway Department, and Federal Highway Administration, Cornell University, Ithaca, NY.
- "Performance of Deep Excavations in Boston Marine Clay Stabilized by Deep Mixing Methods", McGinn, A.J., (2003), Ph.D. Dissertation, Cornell University, Ithaca, NY.
- "Performance of Deep Mixing Methods at Fort Point Channel", with O'Rourke, T.D., (2003), prepared for Bechtel/Parsons Brinkerhoff, Massachusetts Highway Department, and Federal Highway Administration, Cornell University, Ithaca, NY.
- "Study of Stability and Soil Mix Performance during Dredging Adjacent to Ramp D", with O'Rourke, T.D., (1999), prepared for Bechtel/Parsons Brinckerhoff, Massachusetts Highway Department, and Federal Highway Administration, Cornell University, Ithaca, NY.
- “Case History of an Excavation Stabilized by Deep Mixing Methods”, with O’Rourke, T.D., Dewsnap, J., and Stewart, H.E., (1998), Design and Construction of Earth Retaining Systems (GSP 83), Eds. Finno, R.J., Hashash, Y., Ho, C.L., and Sweeney, B.P., ASCE, Reston, VA, pp.41 to 62.
- "Parametric Study of Proposed Excavation for Ramp D Sta. 29+00", with O'Rourke, T.D., (1998), prepared for Bechtel/Parsons Brinckerhoff, Massachusetts Highway Department, and Federal Highway Administration, Cornell University, Ithaca, NY.
- "Performance of Excavations Stabilized by Deep Soil Mixing", with O'Rourke, T.D., Dewsnap, J., and Stewart, H.E., (1997), prepared for Bechtel/Parsons Brinckerhoff, Massachusetts Highway Department, and Federal Highway Administration, Cornell University, Ithaca, NY.
