The utility model discloses a big slenderness ratio is striden to one side and is encircleed rib structure, including big slenderness ratio iron and steel arch rib, main reinforcement concrete pile foundation and support column mount pad, two main reinforcement concrete pile foundation installs the lower surface at the reinforced concrete cushion cap, two the intermediate position department of big slenderness ratio iron and steel arch rib is provided with main wind brace, two the left and right sides at big slenderness ratio iron and steel arch rib is installed respectively to the support column mount pad. The utility model discloses a structure scientific and reasonable, convenient use and safety, moreover, the steam generator is simple in structure, be provided with big slenderness ratio iron and steel arch rib and big slenderness ratio iron and steel arch rib mount pad, the bridge floor is when using for a long time, the movement joint can not appear, thereby save time and labour go the maintenance, and then can not influence transportation, promote national economy's development, and be provided with supplementary reinforced concrete arch rib, it is more firm to make the bridge, be provided with weighing sensor, can measure the weight of the wheel that goes on the reinforced concrete bridge face.