Research Of Interaction Between Mat And Foundation For Mat-type Jack-up Platform

Jack-up platform was first appeared in 1955. Because of its small motion range, good mobile and operating performance, the Jack-up platforms are widely used in the world. It is also the main type of mobile platform which is used in offshore oil exploration and offshore construction.There are two types of Jack-up platforms according to the mat types, shoe and mat. The mat type is suitable for the soft foundation. The function of the mat is to support the upper structure and transfer the load to the soil. There are several geometry types of the mat, for instance, the rectangular, square and ’A’ type. In china , there are some mat type Jack-up platform working in Bohai bay, like Bohai Zili, Huahai 1, Bohai 6, and Bohai 8.The main scale of the mat depends on the vertical load, wave load and current load. Besides, the seepage force applied on the mat which is generated from the foundation should not be ignored. However, the seepage force is always omitted in researches. Because of the high requirement of the foundation bearing capacity and anti-slip ability, the research on the mat bottom’s seepage force is necessary.The research is based on the ocean soil consolidation and percolation theory. In the research the interaction between the structure and soil is simulated using ABAQUS finite element software is proposed the calculation method of the rectangular mat bottom’s seepage force. This method will be helpful for the structure stress analysis and risk assessment of the Jack-up platforms.