Arch Engineers faced a significant engineering challenge in a truss bridge installation project that required mid-lift modifications. Initially designed to land on two light piers and be installed in three pieces, the plan changed after mobilization. The revised plan involved landing the bridge on two abutments, installing it in two pieces, and incorporating a mid-air splice connection. Additionally, the rigging needed to be modified mid-lift, changing from an 8-pickpoint lift to a 6-pickpoint lift to accommodate the capacity limitations of the available cranes.
Our first scope of work was to alter the connection design to comply with the new installation plan proposed by the General Contractor. This required revisiting the initial design and making necessary adjustments to ensure the new connections met the revised installation demands without compromising structural integrity and safety. Arch Engineers meticulously analyzed the existing design, making precise alterations to accommodate the new installation methodology and ensuring all structural elements remained robust and secure.
The second scope involved the review and approval of the mid-lift splice connection and the rigging modification plan. This included a thorough analysis of the proposed splice to ensure it could be executed safely and effectively. Our team verified that the modified rigging plan could handle the altered load distribution, ensuring the crane’s maximum capacity was not exceeded. The successful transition from an 8-pickpoint to a 6-pickpoint lift while in mid-lift highlighted our ability to adapt to challenging conditions and deliver innovative solutions.