这座36岁的西西雅图桥的紧急稳定在外部之后达到了一个新的里程碑post-tensioningand the release of a damaged Pier 18 bearing was completed Nov. 10, allowing crews to move toward wrapping girders in carbon fiber.
The Seattle Dept. of Transportation closed the bridge in March due to cracks. Kraemer North America was hired under an emergency contract to stabilize the structure. WSP provided the engineering.
在释放18号码码头的凸起和损坏的轴承之前，克雷默（Kraemer）增加了外部张紧后，以支持现有的内部张紧系统。新的股线沿着梁内部的梁室底部和通过偏离器块之间的底部延伸，以帮助稳定桥梁。安装后，包括将新链螺栓固定到码头15到18之间的大梁内部的支架，机组人员将它们收紧了10％，从而使桥在轴承释放期间移动。成功释放轴承后，将链完全收紧。它们旨在帮助防止在西雅图岛和港口岛之间穿越杜瓦米什河的2,600英尺长的高层结构上进一步破裂。
Kraemer will also replace the lateral bearings on the east end of the bridge that allow the bridge to expand and contract with temperature and loading changes. The bearings—rectangular pieces of synthetic rubber neoprene—act as a cushion to separate the box girder from the column cap. The bearings at Pier 18 became compressed and bulged, restricting movement of the bridge and creating additional pressure on the surrounding area, transferring stress through the bridge.
下一步将是用碳纤维包裹大梁，以提供额外的强度。
Metal fabricator Vigor supported Kraemer by crafting the structural steel for the temporary access platforms and creating the 48 steel brackets, each weighing between 3,500 and 4,500 pounds, for the post-tensioning. Vigor, which builds and repairs boats on Harbor Island in the shadow of the bridge, had a “vested interest in preserving safety,” says Chris Palmer, Vigor’s vice president of production fabrication.
西雅图市长珍妮·杜尔坎（Jenny Durkan）仍在权衡她在桥梁未来的选择。和HNTB，工作队已经对选项进行了成本效益分析，现在包括全面维修，上部结构更换，完全更换或隧道。Durkan将于11月16日举办虚拟市政厅，以获取社区的反馈。最终决定是杜尔坎。
No matter the conclusion, emergency work continues and SDOT expects the bridge to remain closed through 2021.
