Abstract: In this paper, based on the conditions of the thick silt and peaty soil strata in a highway in Guangdong Province, the formation parameters were obtained through field tests, and a numerical model calibrated with the in-situ mechanical characteristics was established. The accuracy of the numerical analysis was verified by using the field measured data. At the same time, the distribution pattern of the displacement and the bending moment of the pile under the lateral loads is analyzed by using numerical modeling evaluation. The specific conclusions are as follows: 1. Under the condition of the thick silty and peaty soil formation, piles demonstrate large deformation under the lateral loads. 2. The near-surface soil layer is greatly affected by the laterally loaded pile, and the deformation effect of changing the thickness of the silty and peaty layer on the pile is not obvious. 3. The transmission of the pile displacement and the bending moment is mainly distributed in the silty and peaty layer, and the transmission range of the lateral displacement and the bending moment is only carried out in a small range on the pile side.

Key words: Lateral Loads, Thick Soft Soils, Finite Difference Method, Numerical Simulation