Train-induced vibration mitigation based on foundation improvement

The distance between railway systems and buildings has been significantly reduced due to the rapid development of public transportation. Environmental vibration is increasingly influencing human health and comfort as well as vibration-sensitive equipment. To alleviate the issue, amplifying the coupling loss between soil and building using foundation improvement techniques, is an effective way to mitigate building vibration from external sources. In this study, a 4story building need to be built over the railway was used to study the vibration mitigation by foundation improvement. The vibration mitigation performance of foundation design parameters, including foundation type, shear wave velocity of soil, distance from the source, pile diameter, pile length, dimension of the pile cap, and pile group, were studied by a finite element method model. A guideline for optimizing foundation design, which can effectively improve the coupling loss between soil and foundation, has been proposed and applied to the construction of a 4-story building. The train-track dynamic model and the full-scale track-ground-building finite element method model were built to predict the proposed building vibration with the designed foundation. The measurement was conducted before and after the building construction to validate the accuracy of model and the feasibility of the foundation improvement design. The soil-foundation coupling loss is significant from 10 to 80 Hz, which indicates the foundation improvement for vibration mitigation by amplifying the coupling loss is feasible.