Application	PLAXIS 2D
Version	PLAXIS 2D 2024.3
Date created	2 June 2025
Date modified	2 June 2025
Original author	Richard WITASSE - Principal Application Engineer
Keywords	PLAXIS 2D, Soil nailing, Shotcrete, Excavation Support, Phi-c reduction, Safety factor, Embedded beam

 

This document presents a comprehensive 2D finite element analysis of a soil nail wall using PLAXIS 2D. The study involves the simulation of an excavated retaining system stabilized with shotcrete and multiple rows of soil nails. The geometry of the model, including the excavation dimensions and wall layout, is shown in Figure 1 and forms the basis for the numerical simulation.

A key aspect of the analysis is the modelling of soil nails using embedded beam elements in PLAXIS. This approach allows for a realistic representation of the structural behaviour of the nails, including their axial capacity and interaction with the surrounding soil through mobilized skin friction. The nails are connected to the shotcrete facing and staged in sequence with the excavation levels to reflect realistic construction practices.

The report follows a step-by-step modelling workflow, including the definition of project and soil properties, staged construction phases, and interpretation of results such as wall displacements, internal forces in structural elements, and safety factor evaluation using a phi-c reduction analysis. The objective is to demonstrate how PLAXIS 2D can be used to simulate and assess the performance of soil-nailed retaining structures under excavation-induced loading.