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NEWS

Bradshaw Begins Construction in Chattanooga, TN
Bradshaw has begun construction of three tunnels as part of a stormwater sewer improvement project. The City of Chattanooga (Owner) has contracted Civic Engineering & IT Inc. (Engineer) and Wright Brothers Construction Co. Inc. (General Contractor) to construct the project, with Wright selecting Bradshaw as tunneling subcontractor. The three tunnels will be constructed utilizing mechanized Akkerman tunnel shields with cutterwheels, two tunnels at 86-in. diameter (Akkerman WM720C) and one at 74-in. diameter (Akkerman WM600C). The smaller diameter tunnel will be a 250 ft drive, direct jacking 72-in. FRP as the final product pipe. The two large diameter tunnels will pass underneath active Norfolk Southern Railroad lines, requiring the installation of 84-in. steel liner plates to facilitate the installation of 66-in. (195 lf) and 60-in. (135 lf) FRP. All three tunnels will be excavated through foundry sand fill, with fragments of glass and slag expected. Contaminated ground is expected, requiring extensive safety measures to be implemented to guarantee the safety of all involved with the work. Construction was expected to begin on the 72-in. direct jack in late winter 2016, with the first railroad crossing immediately after. The second railroad crossing will occur in fall 2017 Read More

Bradshaw Awarded NUCA Safety Award
The William H. Feather Awards are presented to NUCA member companies who have shown significant commitment and effort to safety within their companies. Judging is based on outstanding safety records, safety statements, and safety program information. Award

Masters of Microtunneling
The Microtunneling Industry in association with the Microtunneling Short Course recently recognized Lester M. Bradshaw, Jr. and 10 of his employees, with experience ranging from 20 to 30 years, for their outstanding microtunneling industry excellence; declaring them all Masters of Microtunneling. Award

Expanding the Science of Microtunneling
The Microtunneling Industry in association with the Microtunneling Short Course recently presented the Microtunneling Achievement Award for Microtunneling Excellence to Lester M. Bradshaw, Jr. for expanding the science of microtunneling and by advancing its Art. Award

Bradshaw Begins Construction in Washington, D.C.
Bradshaw Construction Corporation is beginning construction on a $16M sewer project with the DC Water and Sewer Authority in Washington, DC. The project consists of approximately 4,300' of 24” sewer interceptor, including 2,600’ to be installed by microtunneling in four drives, with the longest being 1,860’ along Oregon Avenue at depths of up to 90’. A 60” casing will be tunneled using a Herrenknecht AVN-1200 MTBM, in which the 24” PVC carrier pipe will be installed. Subsurface conditions will consist of Tonalite rock ranging from slightly weathered to highly decomposed. The project also includes the installation of nine access shafts, 1,500’ of open cut sewer installation, three live connections to the existing sewer system and the abandonment of the existing 15” sewer the new 24” one will be replacing. All work will be installed within Oregon Avenue, bordering a congested, residential area, and Rock Creek Park, owned by the National Park Service. Shaft excavation is schedule to begin this winter, with an estimated completion of Fall 2018. 

Bradshaw Awarded NUCA Safety Award
The William H. Feather Awards are presented to NUCA member companies who have shown significant commitment and effort to safety within their companies. Judging is based on outstanding safety records, safety statements, and safety program information.  Read More

Bradshaw Begins Construction in Raleigh, NC
Bradshaw has begun construction on a $21M sewer project in Raleigh, NC. The project consists of approximately 3,000 feet of 1-pass and 2-pass microtunneling at 11 locations. The City decided to let a separate trenchless general contract in advance of the 30,000 feet of future open cut pipeline contracts. Casing size is 60” and 72” and the FRP pipe is 42” to 57”. Subsurface conditions range from alluvium and residual soil to partially and unweathered hard granitic rock and mixed face 

 

PUBLICATIONS

The Challenges of Rock Microtunneling
By Lester M. Bradshaw, Jr. - Microtunneling Short Course Seminar - University of Colorado
From a Contractor's Perspective . . . Bradshaw's Experience (54 years as a tunneling contractor, 26 years as a microtunneling contractor, 25 years using conventional rock TBMs, 13 years microtunneling rock). Power Point Presentation

Experience Key for Pennsylvania Intake Project
By TBM - Tunnel Business Magazine . . .
In tunneling, like many other aspects of life and work, experience is the best guide. For Bradshaw Construction, experience was the key in a tricky intake project it completed recently in Pennsylvania.

The project - the Wildcat Point Raw Water Supply for the Dominion Electric Cooperative - was completed within sight of another intake project completed by Bradshaw Construction for another energy company a few years earlier. Read More

Microtunnel in Birmingham Rock
By Mike Wanhatalo, Project Engineer - SESTT - Southeast Journal of Trenchless Technology
Bradshaw Construction Corporation (Bradshaw) recently completed work on the Carson Loop Phase VI-B project in Leeds, Alabama. The project owner was the Birmingham Water Works Board and the design engineer was Volkert and Associates. Bradshaw was chosen as the microtunneling subcontractor by the prime contractor Rast Construction. The project increased water capacity delivered to a rapidly developing commercial and residential area by adding 7,165 LF of 36-inch DIP water main. The project required a single 1,165 LF microtunnel drive of 60-inch steel casing. Read More

Advantages of Microtunneling in Wet Sands & Clays
By Doug Piper, Estimator/Project Manager - MASTT-Mid Atlantic Journal of Trenchless Technology
Bradshaw Construction Corporation (Bradshaw) has recently subcontracted three microtunneling projects in the Hampton Roads area of Virginia: 1. East Princess Anne Trunk Force Main Reinforcement Project; 2. College Drive Waterline Project; 3. Hampton Roads Sanitation District (HRSD) Division C Sewerage System Improvements. Read More

Drill & Blast: Case History
By Lester M. Bradshaw, Jr., Eric Eisold, Todd Brown - CSM Short Course Presentation
Tunnel boring machines (TBM) are regularly specified to excavate hard rock tunnels, particularly near existing sensitive structures such as dams, where vibration damage is considered critical. The drill and blast tunnel method is not always considered to be an option. Depending on the length of the tunnel, the rock conditions and the proximity to critical structures, tunneling by drill and blast hand mining can be accomplished as safely as the TBM method yet can be more economical. Bradshaw Construction used the drill and blast hand mine method to successfully install a combined spill way and raw water main tunnel for the Rivanna Water & Sewer Authority at its New Ragged Mountain Dam in Charlottesville, VA.  Read More

Case History of the York Energy Center Intake/Blowdown
By Eric Eisold & Sean McIntee - Presentation
The York Energy Center project in Delta, PA consists of 565 megawatt generating facility that recovers heat from hot gas exhaust leaving gas turbines. The combustion turbines burn either natural gas or low sulfur diesel fuel oil. Combined, these two power cycles consume 70-80 percent of the fuel needed by a traditional fossil-fired boiler/steam turbine generator plant. A microtunnel solution to installing the cooling water intake and return was developed by the owner, contractor & tunnel subcontractor. A 460 m x 1500 mm (1500 ft x 59 in) steel casing was jacked through rock and zero blow count river deposits that served as the intake. A 406 mm (16 in) HPDE line was installed inside the casing to serve as a return. Financial and environmental considerations for the microtunneling solution led to replacing the original twin pipeline trenched design. The TBM was recovered from under Conowingo Lake along the Susquehanna River. Read More

1,133 Feet of Microtunneling
By Michael Gibson, P.E. & Lester M. Bradshaw, Jr., President Bradshaw Construction Corporation - Southeast Journal of Trenchless Technology
Bradshaw Construction Corporation recently completed a single 1,133' microtunnel drive of 96" OD Permalok steel casing for the Metropolitan Sewer District (MSD) of Louisville & Jefferson County, Kentucky. This paper highlights certain challenges of slurry microtunneling long drives of steel casing in fine-grained soil conditions, as well as project specific difficulties related to the microtunneling and installing two carrier pipes to design grade through a single casing.  Read More

Microtunneling in Mixed Face/Mixed Reach Hard Rock
By Lester M. Bradshaw, Jr. - CSM Microtunneling Short Course
Bradshaw Construction Corporation recently completed a microtunnel drive that crossed the Schuylkill River in Reading, Pennsylvania. The project consisted of 436 feet of 60 inch steel casing with an average depth of 35 feet at the shafts. Ground cover under the river was as little as 5 feet. Mining conditions began with a mixed face of non-cohesive gravel in the top of the heading overlaying fractured dolomitic rock at the bottom. The heading transitioned to a full face of fractured dolomitic rock approximately half way in to the drive. The rock had unconfined compressive strength (UCS) values of up to 34,300 psi. This paper discusses the challenges associated with the project, including limited work space, rock excavation in the shaft and tunnel, disc cutter wear and changes, managing the water table, and receiving the MTBM in a 9 foot ID drilled shaft. Read More

Rumble in the Ragged Mountains
By Lester M. Bradshaw, Jr., Todd Brown, Eric Eisold - World Tunneling
Tunnel boring machines (TBMs) are regularly specified to excavate hard-rock tunnels, particularly near sensitive structures such as dams, where vibration damage is considered critical. The drill-and-blast tunnel method is not always considered to be an option. However, depending on the length of tunnel, the rock conditions Read More

 

EVENTS

Bradshaw Construction Corporation Celebrates 35 Years in Tunneling
With over five decades of experience, we've earned respect as technological innovators through the construction of highly difficult tunneling projects. We owe that success to our commitment to excellence, craftsmanship, safety, and by earning our clients' trust. 

Eric Eisold Appointed Vice President of Bradshaw Construction Corporation
Eric D. Eisold, P.G., has been named Vice President of Bradshaw Construction Corporation. He previously held the position of Area Manager, responsible for the day-to-day management of estimating and project management departments ensuring our projects are completed on time and within budget.

In his new position, Eric will be responsible for expanding the pipeline of new business and building the company’s market position as well as continuing his management role in estimating and operations. With over 30 years of experience in heavy civil construction, Eric has provided our clients with the best tunnel construction and value engineering possible.

“I believe Eric’s leadership, experience and past success uniquely qualify him to help diversify and expand our services in the tunneling industry,” Lester M. Bradshaw, Jr. said.