Constitutive Modeling of Physical Properties of Coastal Sand during Tunneling Construction Disturbance

Abstract

This paper presents a simple but workable constitutive model for the stress–strain relationship of sandy soil during the process of tunneling construction disturbance in coastal cities. The model was developed by linking the parameter K and internal angle φ of the Duncan–Chang model with the disturbed degree of sand, in which the effects of the initial void ratio on the strength deformation property of sands are considered using a unified disturbance function based on disturbed state concept theory. Three cases were analyzed to investigate the validity of the proposed constitutive model considering disturbance. After validation, the proposed constitutive model was further incorporated into a 3D finite element framework to predict the soil deformation caused by shield construction. It was found that the simulated results agreed well with the analytical solution, indicating that the developed numerical model with proposed constitutive relationship is capable of characterizing the mechanical properties of sand under tunneling construction disturbance.

Structure–Seabed Interactions in Marine Environments

“…Nine (9) papers are included in this Special Issue: one review article [1] and eight research articles covering two main themes-(1) the mechanisms of marine sediments in the Yellow River Delta [2] and a field study [3] and (2) structure-seabed interactions in the vicinity of tunnels [4,5], spudcans [6], pile foundations [7], breakwaters [8], and pipelines [9]. More details on each contribution are summarized here.…”

“…The construction of a tunnel in the marine environment has attracted much attention from coastal and geotechnical engineers due to the ongoing demands of tunnel construction in coastal cities. To appropriately model the physical properties of coastal sand during the construction of tunnels, Zhu et al [4] presented a series of experimental results of triaxial compression tests for dry and saturated sand with different initial void ratios. The experimental results were used to modify the disturbance function in terms of the parametric constant (K) and friction angle of the soil (φ), utilizing disturbed state concept (DSC) theory.…”

Study on Cyclic Shear Properties of Siliceous Sand–Steel Interface under Different Normal Loading Conditions

“…Sand is a common and representative geotechnical medium [1,2], which is widely distributed in coastal zones, rivers, and foothills due to geographical conditions such as terrain and sedimentary environment. In recent years, with the rapid development of economy, more and more energy projects and high-speed transportation projects are built along rivers and coastal areas, such as offshore wind turbines [3,4], offshore drilling platforms, sea crossing bridges, etc.…”