Settlement of CFG Composite Foundations of the Beijing-Tianjin Inter-City Rail Construction

The Beijing-Tianjin inter-city rail line is the first 350 km/h high-speed railway in China using all Bogle slab tracks that require a post-construction settlement of less than 15mm. The data from monitoring soil stress and settlement characteristics of different parts of the CFG composite pile foundation shows that the stress is large and changes rapidly on the top of stakes in the period of construction and precompaction. Analysis of the data using hyperbola and Hushino methods indicates that 70% of the settlement from preloading occurs in 40 days and forecasts that the settlement of subgrade after acceptance satisfies the requirements of Code.