Abstract：
Local non-compactness may occur in the sand foundation of an immersed tunnel after sand filling due to different trench depths, sand filling pressures and water-sand ratios, which may cause uneven loading on the sand foundation, tunnel element cracking, or a great impact on the force bearing of the structure and joint waterproofing. Using the immersed tunnel of the south extension line on Fenjiang Road as an example, this paper establishes a relevant full-scale model, proposes a detection scheme for the density of a sand foundation through a contrast test (i.e., adopting the surface wave method and elastic wave imaging method), gives the evaluation factor of density (R) based on an analysis of mass detection data, and builds a relationship between the evaluation factor and the sand foundation density.
2016, Vol. 53 