A concept for the new Ocean Beach pier
During the community outreach phase of the Ocean Beach Pier Renewal Project, the number one request of the community was that the pier reduce impacts to the environment and be a model for sustainability. The community also voiced that they want a pier that respects the past yet looks to the future. Responding to these wishes of the community, the pier concept consists of two structures.
The first half of the pier is a suspension bridge with a post tensioned concrete deck. This suspension bridge would drastically reduce impacts to the ocean floor as well as wave forces on the bridge structure itself. Each vertical support in the traditional pier requires drilling in the ocean floor down to bedrock, inserting a steel tube and infilling with concrete. This suspension concept reduces the impact to the ocean floor by more than 50%.
The second half of the pier would be a historical replica of the original pier, saving the communities beloved cafe and the unique Y end of the pier. The only alteration to this historical end would be a reduction in the number of vertical supports, further reducing impacts to the ocean floor yet maintaining the experience of the original pier.
A curved accessible ramp creates a smooth transition from the boardwalk up to the pier. New surfing observation seating is built into the ramp.
pier entry on Niagra
Entry to the historic end of the pier
(a) Hollow anchor lowered into place with crane, filled with sand for counter weight; (b) and (c) first stage of pylon raising using temporary towers and second pylon raising; (d) erection of main suspension cable tubes; (e) erection of deck segments; (f) deck tendons stressed - before grouting of the strands of main suspension cables
Elements of the structural system can be built off site and lowered into place with a crane.
Approach to pier on accessible ramp
Completed in 1993, the Swiss Bay Bridge is a pedestrian bridge in the Czech Republic with a span of 826 feet. The cost for the structure was approximately $1,000,000. The concrete decking is post tensioned, creating an extremely stable structure with super thin decking panels.
Closing Remarks from a report from the Precast Concrete Journal regarding the Swiss Bay Bridge: “Although the Swiss Bay Bridge has a very slender deck, pedestrians and bicyclists feel no unpleasant bridge motion when walking or standing and admiring the surrounding landscape. The structural system used in the design of the bridge proved to be safe, economic and minimally disrupting to the surrounding environment.”