Research on Foundation Damage Modes and Bearing Capacity in Hard Soil with Finite Element Method

The bearing capacity of hard soil shell over a layered foundation is the key for calculation of penetration of jack-up leg footing. Currently, the ultimate bearing capacity of layered foundation is usually calculated with approximation method. With this approximation method,the damage modes and the stress of foundation under middle load can not been solved fully. The Finite Element Method has been used for simulating the damage process of foundation. The study results reveal that the plastic damage of soft stratum occurs more easily with the increasing of B/H value,and the ultimate bearing capacity reduces obviously. The soft stratum should not influence the ultimate bearing capacity of foundation when the numerical value of B/H is less than 0.3. Results show that the Finite Element Method matches well with the method of 3:1 Expansion Angle. Through analysis on a penetration example of jack-up leg footing, the analyzing results with Finite Element Method are coincided with the actual measured results.