A leading-edge tunnel construction company, Schnabel provides innovative geostructural design and construction services for tunnel shaft projects throughout the United States.


Tunnel and shaft construction requires specific in-depth knowledge and special expertise. A design-build tunnel and shaft construction company, Schnabel leverages decades of experience to provide excavation support and cut-off walls to allow for the construction of cut-and cover-tunnels and ramps, access shafts, and other underground structures.

A versatile design-build specialty foundations company, Schnabel can also provide jet grouting to stabilize the ground and reduce groundwater seepage around penetrations through tunnels and shafts. Schnabel specializes in self-supporting circular secant pile shafts that do not require bracing or tiebacks that can complicate excavation of the shaft.

Browse our company project portfolio and see why Schnabel is a top tunnel and shaft construction company with a diverse service catalog.

A design-build contractor, Schnabel provides expert Geostructural Design and Construction services for tunnel shaft projects.
A design-build contractor, Schnabel provides expert Geostructural Design and Construction services for tunnel shaft projects.

Your Key to Successful Tunnel and Shaft Construction.

Tunnel & Shaft Case Studies

Secant Pile Shafts

San Marcos River ARWA Tunnel Shafts | Martindale, TX

Two circular access shafts, crucial for a water supply line project, were designed and constructed by Schnabel using overlapping secant piles filled with unreinforced concrete. The launching shaft included the installation of 42 drilled secant piles, descending to depths of up to 69 feet and the receiving shaft included featured 24 drilled secant piles, reaching a depth of 58 feet. Schnabel used specialized Bauer drill rig equipment with sectional 1180 mm casing and a casing drive adapter to ensure proper alignment and verticality of the piles.

Secant Pile Shaft

Romeo Arm Interceptor Deep Sewer Repair | Sterling Heights, MI

Schnabel was hired by Oscar Renda to install a 34.5-foot inside diameter secant pile shaft. This work consisted of 60 overlapping secant piles ranging from eight feet to 51 feet in depth. Shallow drill depths of 8 to fourteen feet followed the top radius of the tunnel. Once clear of the tunnel to the sides, 38 feet deep primary shafts and 51 feet deep secondary shafts were drilled below subgrade to ensure basal stability of the excavation. Reinforcing steel consisting of W21x182 wide flange sections were placed in secondary shafts.

Leveraging Decades of Experience for Seamless Construction Below.


Schnabel is the sector’s most operationally efficient Geostructural Design & Construction contractor. We optimize efficiencies by leveraging decades of experience and design/build expertise to innovate processes and approaches that are consistently proven to deliver optimal outcomes for our clients.