Saeed Darvishi Alamouti - Ph.D Candidate, University of Tehran;
Iman Batmanghelichi - M.Sc. in Marine Structures, Petro Sahel Persian Development Company;
Alireza Sadat Hosseini - Ph.D Student, University of Tehran;
Amir Davazdah Emami - Head of Marine Discipline, Petro Sahel Persian Development Company;

As an alternative for transferring bridge pier huge loads to the ground, box caisson could be used. For Persian Gulf Bridge, massive box caisson type footings are used. Persian Gulf Bridge is the main part of the Persian Gulf Regional Transportation Network Project which connects Laft harbor in Qeshm and Pohl Harbor in the mainland. The bridge caissons together with their pylons weigh about 17000 tons. One of the principal sequences in Persian Gulf Bridge construction procedure is transportation of the caissons to installation location and submerging them to reach their final position. The main challenge in caissons lowering is that they miss their floating stability when water plane crosses the pylons after about one meter of sinking.In this paper, an overview of floating stability issues during lowering of the PGB caisson is given and a new alternative for floating stability and lowering procedure is introduced. MOSES software is utilized in order to perform the floating stability calculations during lowering in each method.

Persian Gulf Bridge, Caisson, Lowering, Floating stability, MOSES