Redwood Road Landslide Repair – Castro Valley, CA

Geotechnical Investigation and Construction Observation

A section of Redwood Road in rural Alameda County failed during exceptionally heavy rainfall in the winter of 2016/2017 and subsequently closed the roadway to all through traffic. AKA was contacted by the Alameda County Public Works Agency to lead the investigation and repair design under our on-call contract with the County. AKA performed a thorough geotechnical investigation including advancing four borings up to about 40 feet deep within the landslide zone. The investigation concluded that a relatively deep landslide had damaged the Redwood Road right-of-way and may have been a re-activation of an older landslide. Following the investigation, we worked closely with our design team to develop plans and specifications suitable for contractor bidding. The repair plan included a steel beam pier and concrete retaining wall with ground-anchors (tie-backs) to provide resistance for the design lateral loads. Surface and sub-surface drainage was also addressed in the design. Construction of the repairs began in September 2017 and Redwood Road was re-opened in April 2018. AKA Engineers performed construction management during construction operations, including pier drilling, tie-back installation, and grading.

I-880/Route 262 (Mission Boulevard) Interchange – Fremont, CA

Geotechnical Design and Materials Report for Grade Lowering
Retaining Wall Investigation

I-880/Route 262 (Mission Boulevard) Interchange - Fremont, CAAKA provided geotechnical engineering services to Parsons Brinckerhoff Quade & Douglas in support of their work on the I-880/Route 262 Interchange in Fremont, California. Route 262, also known as Mission Boulevard, is a major northern California transportation link connecting the I-880 and I-680 freeways. Geotechnical aspects of the project include the construction of two new freeway ramps and the lowering of the road grade in order to provide adequate vertical clearance between two new railroad bridges. A notable geotechnical consideration for the project was the presence of a relatively high groundwater table. AKA conducted a two-phase investigation that included new pavement cores within the traveled way and shoulders, and borings beyond the pavement edge. Our Phase 1 report documents pavement and subgrade conditions and presents recommendations for earthwork, pavements, and underdrainage. Our Phase 2 report included logs of borings drilled at planned wall locations and geotechnical recommendations for retaining wall design. The I-880/Route 262 Interchange is a State highway and AKA’s project deliverables are prepared in accordance with rigorous Caltrans guidelines.

Centennial Drive Landslide Repair and Stability Evaluations – Berkeley, CA

Landslide Repair Conceptual Designs, Plans, and Specifications
Geotechnical Construction Services
Geotechnical Evaluation of Future Slope Stability Concerns

Centennial Drive Landslide Repair and Stability Evaluations - Berkeley, CAAKA provided geotechnical engineering services to the University of California, Berkeley, Capital Projects division relating to slope stability concerns along Centennial Drive. The subject section of the drive is located within Strawberry Canyon and creekbank erosion and landsliding are key concerns.  AKA’s initial scope of services included the evaluation and repair of a section of the drive that failed in early 2006 following a series of heavy winter rains. For this fast-track project, AKA worked closely with University stakeholders to develop an aggressive project implementation plan under which repairs were completed in the fall of 2006. As a follow-on to our initial scope, AKA was asked by the University to investigate and identify other locations along the drive that could pose a future slope stability concern. These preliminary evaluations were used by the University to prioritize funding for future proactive engineering projects.

Norbridge Avenue Extension – Castro Valley, CA

Geotechnical Investigation

Norbridge Avenue Extension - Castro Valley, CAThe Alameda County Department of Public Works selected AKA to provide a geotechnical investigation for the extension of Norbridge Avenue in Downtown Castro Valley. The road extension is a main thoroughfare that carries traffic to and from the Castro Valley BART Station. Geotechnical design issues addressed by AKA included evaluation of the potential for consolidation of existing fill material below the proposed roadway alignment, crossing of a flood control channel, and design of foundations for sound walls.

Ascot Parkway and Redwood Parkway – Vallejo, CA

Geotechnical Study
Construction Monitoring Services

Ascot Parkway and Redwood Parkway - Vallejo, CAAs part of the Northgate mixed-use development area in Vallejo, a series of new roadways were constructed. AKA provided geotechnical studies and construction monitoring services for the extension of both Ascot Parkway and Redwood Parkway through this area.