RHC Engineering

Bridge Final Design:

DNR Lower High Point Trail Bridge. RHC provided final design and alignment alternatives, managed and led the final plan, specification, and cost estimation for the 30%, 90%, 100%, and ready for bid package, and provided construction technical support. The new 200 foot long steel truss bridge is 30 feet above the creek, with unique curved columns on spread footings.

Bridge Concept Design:

WSDOT SR 520 West Corridor. RHC provided concept design plans, preliminary engineering, and cost estimates for structures in the corridors. The structures include two pedestrian bridges, that are about 400 foot, made of long curved and post-tensioned box structures, one approximately 200 foot long pedestrian tunnel, over 20 retaining walls, one HOV ramp vehicular bridge designed for future light rail compatibility, storm water structures. Other services include final design of a signal pole foundation, post-design construction support for the West Approach Bridge North, refining structural design criteria and seismic analysis for bridges in the corridor.

Bridge Seismic Retrofit:

RHC performed vulnerability analysis for this 380 foot long bridge under strength and extreme event limit states, identified deficient elements, and recommended ductile and non-ductile retrofit strategies considering protecting the historical columns with unique architectural features.

SDOT NE 45th Street Viadcut East Approach. RHC reviewed the existing bridge's lateral resistance system, performed vulnerability analysis and identified deficient elements on columns, crossbeams, and girders, and recommended retrofit strategies. The East Approach included 5 unique units of irregular reinforced concrete superstructure including multi-cell box girders, T beam girders, and reinforced concrete solid slabs.

Bridge Inspection and Assessment:

City of Bainbridge Island Pedestrian Bridges. RHC provided inspection and load rating for two pedestrian bridges, and delivered replacement concept alternatives and cost evaluation for one timber bridge that was identified structurally deficient. RHC's field inspection found a sway pier on the timber bridge, and load rating found deficient glulam girders that were previously rated as sufficient. Three replacement alternatives with cost data were delivered.

Bridge Load Rating:

SDOT West Dravus Street Bridge. RHC Engineering provided load rating for this two-span reinforced concrete bridge. RHC did field verifications of the bridge condition. The rating analysis considered construction staging and SDOT’s special hauling truck. RHC also did independent QA/QC checks by comparing computer software output with hand calculations.

Bridge Plannnig Study:

SDOT Ship Canal Crossing. The Ship Canal Crossing Study project studied a number of different options to improve the West Seattle multi-model transportation and pedestrian experience over the Ship Canal. RHC Engineering studied two options of pedestrian and bicycle shared-use bridges over Ship Canal. The study included alignment layouts, structural analysis, and planning level bridge structural design. The study overcame many geometrical constraints for the approach landing.