Abstract: In order to provide guidance for the deep excavation and support construction for an underground comprehensive utility box culvert, a finite element three-dimensional numerical model was established to simulate the construction process of the deep excavation adjacent to a highway. In the establishment of the numerical model, the vehicle load on the adjacent road is simplified as a sinusoidal loading pattern, then the box culvert site is excavated in lifts, and the data for the excavation supporting structure and the deformation of the adjacent road surface are obtained. The results show that the maximum horizontal displacement of the supporting structure induced by the excavation of the proposed box culvert adjacent to the highway occurs after construction with a maximum value of 4.62mm. The lateral deformation meets the current code safety requirements. In addition, the deep excavation leads to the release of soil stress. The excavation induces a maximum upward displacement of 25.6 mm at the bottom of the excavation and the maximum observed settlement of the adjacent roadways is 25.2mm. This paper also discusses the effect of vehicle speed of the adjacent roadway and the relationship between steel sheet piles embedment depth on the deformation of the excavation supporting structures. The vehicle speed has little effect on the deformation of the excavation supporting structure. Whereas the steel sheet pile embedment depth has a greater impact on the deformation of the excavation supporting structure and the optimum embedment depth for the steel sheet pile is 12 m.

Key words: Deep Excavations, Numerical Analysis Model, Adjacent Roadways, Sinusoidal Loads, Steel Sheet Piles