Civil engineers are more and more often confronted with constructions in urban environment. It is then essential to be able to accurately assess the initial state, and the evolution of the safety during construction stages. While traditional geotechnical engineering has been using a family of simplified approaches for different problems, in association with two-dimensional modeling, the approach adopted herein is integrated, coupling all aspects of the problem, and 3-dimensional, thus offering a significant potential for optimization of constructions. Over the past 20 years, the authors have been developing numerical tools for static and dynamic analysis of soil, rock, structures and flow with the aim of providing to civil engineers a tool which unifies computational geomechanics, structural mechanics and soil-structure interaction within a single theoretical framework, while remaining user-friendly and transparent for the user. Recent developments in Z_Soil.PC are presented in this paper, along with three-dimensional simulations which illustrate the potential of the tool.