Compression modulus of soil layer is a very important parameter for settlement calculation about bridge pile foundation in thick soft clay. According to bridge pile foundation subside of Beijing-Shanghai High-speed Railway

calculation formula for compression modulus related soil depth of soil layer in natural state are obtained by fitting analysis based on data of geotechnical test and the achievement of in-situ test in construction site DK152. On this basis

the finite elements calculation is done; and settlement of pile foundation is in good agreement with displacements of field monitoring. Using neural network

the mapping relation between settlement of pile foundation and compression modulus of soil layer is established. By back analysis of compression modulus of different soil layers and different depths

correlation inversion results are basically identical with calculated values by empirical formula; it is shown that calculation formula for compression modulus proposed in this paper is practicable and accurate; and model generalization and the inverse calculation method are reasonable. This study has certain reference value for settlement calculation of long pile foundation of high-speed railway bridges on deep soft soil.