MassDOT Route 2 over Hoosic River Geotechnical Design

GTR performed design phase geotechnical services for this 300 foot MassDOT bridge replacement consisting of two new abutments and reuse of the existing timber pile supported center pier. The foundation system designed by GTR consists of driven steel H-piles for the replacement of the abutments and drilled micro-piles to supplement the existing pier for the proposed re-use. Geotechnical concerns for the project included pre-drilling through obstructions for the piles to limit vibrations on existing floodwall structures and constructability of the pier rehabilitation.  As Geotechnical Engineer of Record, GTR’s scope included developing and executing  a subsurface investigation that included installed piezometers, streambed sampling, laboratory analyses, analyzing the obtain subsurface data, reviewing construction documents for the existing bridge from several widening and improvement phases in the 1920’s thru the 1940’s, geotechnical analysis, developing technical specifications with testing and quality control requirements, developing specifications for a monitoring plan for the existing structures that include vibration, automated settlement monitoring and tiltmeters.  GTR’s laboratory analyses included Atterberg Limits, unit weight, Unconsolidated Undrained (UU) triaxial, Consolidated Undrained (CU) triaxial, and consolidation tests.  The bridge delivery method is traditional design-bid-build.