Field experimental study on vertical bearing capacity of root-caisson foundation

According to the situation of the shortage of the bearing capacity of the soft and thick covering stratum, the root-caisson foundation, a new type of foundation was introduced. Its construction procedure involves sinking a caisson with reserved holes in the side wall, then pushing prefabricated roots into the soil through the reserved holes by the jack after the caisson has been sank to the design level, and casting concrete to make sure that the roots are fixed with the caisson. The mechanism of vertical bearing capacity of root-caisson foundation was analyzed, and the improvement of bearing capacity due to the soil compaction and the bending resistance of roots was discussed. The self-balanced test method was utilized in the field tests to investigate the vertical bearing behavior of a root-caisson foundation with a traditional one. The result indicates that the roots are capable of activating a large range of soil to bear the load, and with reasonable installation of roots, the ultimate bearing capacity of a root-caisson foundation is greatly larger than that of a traditional caisson foundation. Compared with the traditional caisson, the vertical bearing capacity of root-caisson foundation could be increased by100%.