US-101/Blossom Hill Road Interchange Improvements, San Jose, Santa Clara County, CA

The US-101/Blossom Hill Road Interchange Improvement Project is intended to relieve congestion, improve traffic operations, and improve bicycle and pedestrian connections at the busy interchange. Elements include a new bridge structure for median widening, on- and off-ramp widenings to accommodate new lanes, realigning on-ramp loops, a Class I bicycle path with overcrossing and undercrossing structures, retaining walls, and sound walls.

PARIKH provided geotechnical investigations for the interchange improvements. Scope of work included field investigations with cone penetrometer (CPT) tests, laboratory testing and engineering analyses, and multiple geotechnical and foundation reports. Design recommendations were provided for driven steel pile and cast-in-drilled-hole (CIDH) pile foundations, soil nail and mechanically stabilized embankment (MSE) retaining walls, sound walls, and pavement design. Pile capacity recommendations included mitigation for liquefiable soils in the subsurface. Recommendations were also provided for subgrade strengthening via geotextile reinforcement to mitigate expansive soil effects on pavement sections, as well as considerations for grading and groundwater control.

Congratulations to PARIKH Consultants, Inc. and HMH Engineers, in coordination with City of San Jose and Santa Clara Valley Transportation Authority on receiving the California Transportation Foundation Award’s Project of the Year for the Interstate category, for US-101 Blossom Hill Road Interchange Improvement. These coordinated efforts continue to improve infrastructure throughout California.