The analysis of the ground foundation must take into consideration two main aspects: a simulation of the ground motion as close as possible to reality and the correlation of the ground motion with existing geological conditions. Thus, it can be distinguished two main functions of the soils: the function of a dynamic filter for the seismic movement that come from the source, and the function of a deformable spring for the buildings whose support is. In this paper, the behavior of a site was analyzed from the site response point of view, using different accelerograms of Romanian's earthquake. These accelerograms were recorded during the 1977, 1986 and 1990 earthquakes. In order to perform equivalent linear site response analysis we use the STRATA software for a homogeneous soil layer with more than 10 meters depth. The soil type and the velocity layering were considered constant on the entire soil deposit. The analysis was done both on cohesive and cohesionless soils. The final results have been mapped in terms of soil dynamic characteristics, accelerograms and acceleration response spectrum, under different earthquake excitations.

The purpose is to evaluate ground response of 30 m soil column subjected to different seismic actions. The main foundation layer under investigation is a fat clay specific for Iasi, the Bahlui clay. Three main investigation steps have been followed. The first one consists in laboratory tests using resonant column and torsional shear tests only for Bahlui clay. Degradation curve has been established for both shear modulus and damping ratio. Dynamic parameters of the other layers have been established using empirical models. The second step consists of determination of the site's response spectrum. Equivalent linear one‐dimension analysis using STRATA software has been performed in order to determine the seismic response of the soil column. The analysis results highlight an amplified seismic input motion associated with each soil layer type. They will lead to a better understanding and will improve the characterization of the site response effects, necessary for the local engineers to manage the design of new constructions and to properly consolidate the existing ones.

The analysis by numerical simulations can be applied to building materials subjected to different climatic conditions to envisage the influence of environmental factors in terms of drying time, water absorption and thermal performance of materials. Currently there is a wide variety of new building materials used for insulation, waterproofing and rehabilitation, each contributing in a specific way to constructions improvement during their service life. In time, every building is subjected to degradation due to the action of environmental factors. One of these is water due to its continuous acting under all forms of aggregation: vapour, liquid, solid, each having particular influence on the building's elements. The present paper highlights a numerical simulation of hygrothermal waterproofing characteristics for three different membranes applied on a brick masonry basement wall. The simulation was performed using WUFI2D 3.2 computer software. The information extracted from the analysis results made reference to the materials performance while subjected to moisture transfer processes.