Method for preventing sudden subsidence of open caisson in soft foundation

A method for preventing sudden subsidence of an open caisson in a soft foundation, comprising the following steps:

• S1, determining a position of the open caisson;
• S2, carrying out grouting to reinforce a foundation of the open caisson, and the foundation of the open caisson being located at a bottom of a wall of the open caisson;
• S3, levelling an open caisson manufacturing site;
• S4, manufacturing and installing sections of the open caisson, comprising:
• I, manufacturing sections of the open caisson, and fixedly installing bearing units on the inner sides of the upper parts of the sections;
• the bearing unit comprises a plurality of brackets and a frame, the brackets are fixedly installed on the inner side of the upper part of the section at uniform intervals, the frame is fixedly installed on the plurality of brackets, and a support is fixedly installed at the bottom of the frame;
• and a template is laid on the top of the frame;
• II, enabling the first section to subside;
• III, calculating the mass of the second section, placing a load with the same weight as the section on the bearing unit of the first section, and pre-pressing the first section for 24 h with the load;
• IV, if the first section has no obvious subsidence, taking out the load, and installing the second section by subsidence;
• and
• V, if the first section has subsidence, re-adjusting a construction solution;
• S5, repeating S4 until all the sections are manufactured and the open caisson subsides in place as a whole.