Construction on the $449 million Sixth Street Viaduct Replacement project in Los Angeles is moving forward with intersection improvements near the existing bridge in preparation for the installation of a load test pile to help confirm geotechnical data for foundation design.
Built in 1932, the Sixth Street Viaduct was deemed unsafe and in need of replacement due to a rare chemical condition called Alkali Silica Reaction (ASR) that is affecting its cement supports and weakening concrete.
作为城市中最具标志性和著名的桥梁之一，跨度是洛杉矶河西侧的艺术区与东侧历史悠久的博伊尔高地社区之间的重要联系。古老的结构跨越了整个河流，跨越了近3500英尺，并被用来代表洛杉矶的粗糙而坚韧的胸部，包括许多音乐录影带，电视广告和电影，包括几部Arnold Schwarzenegger“ Terminator”电影。
The design of the new bridge, known as “The Ribbon of Light,” was created by Los Angeles architect Michael Maltzan, winner of the city’s international design contest in 2012. Maltzan is part of the HNTB design-build team, along with contractors Skanska and Stacy and Witbeck. TY Lin International is providing construction management; CH2MHill is the program management consultant; and the project owner is the City of Los Angeles Bureau of Engineering.
替代者是洛杉矶历史上最大的桥梁项目，完成后，新的签名桥将是洛杉矶的天际线和洛杉矶河的标志性补充，因为它有助于改善移动性并连接社区。
The project, which broke ground last February, is currently finishing up improvements to intersections near the bridge that will help make traffic flow more efficient during the three years it will take to construct the new viaduct. Crews are also currently completing the demolition of buildings along the north footprint of the viaduct as well as performing utility relocations in preparation for the demolition of the existing viaduct, which will take place in early 2016.
洛杉矶工程局项目的首席工程师朱莉·艾伦（Julie Allen）表示，替代项目提出了一个引人入胜的协调挑战。
"The Sixth Street Viaduct spans a freeway, 18 railroad tracks, and the Los Angeles River," she says. "Demolition of the existing viaduct and construction of the new viaduct must be coordinated with freeway closures, railroad operations, and rainy season restrictions, which have significant effects on the construction schedule."
她说，新的高架桥非常复杂，旨在通过每列中使用“三重摩擦摆轴承”来承受地震活动。她说：“从高架桥结构到相邻基台和自行车/行人坡道的所有连接都需要隔离接头，使横向运动可达30英寸。”
Allen says the project's next milestone is the installation of load test pile in the next two months and demolition of the viaduct structure will begin in early 2016. Work is slated to complete in early 2019.
该项目正在通过建筑经理/总承包商（CMGC）交付方法进行。这是联邦公路桥梁计划资金和加利福尼亚州的CALTRANS监督的第一个CMGC项目。