Many regions of the globe are subjected to earthquakes and as such any geotechnical structure must be functional under extreme shaking events. Earthquakes can result in the generation of excess pore-water pressure which reduces effective strength and can lead to failure. Dynamic shaking can cause collapse of certain types of soils and dynamic inertial forces can in some cases result in permanent deformation. Loss of strength due to pore-pressure changes and collapse can also result in permanent plastic deformations.
GeoStudio’s QUAKE/W can be integrated with the entire suite of models to allow for dynamic analysis of earth structures. Users can perform a transient Newmark type analysis to determine deformations due to inertial forces. If excess pore-water pressure is generated in a QUAKE/W analysis, dissipation of these pressures can be considered within a seepage (SEEP/W) or stress-deformation model (SIGMA/W). Regions in which there have been a loss of strength and collapse can be identified and permanent plastic deformations can be estimated. Structural supports such as tie-back anchors and sheet pile walls can be included in the dynamic analysis.
Download GeoStudio to view GSZ files
This example demonstrates how the results of a QUAKE/W analysis can be used in conjunction with SLOPE/W to estimate the permanent deformations that may occur as a result of the inertial forces associated with an earthquake.
This type of permanent deformation analysis is referred to as a Newmark analysis.
ProShake is software for one-dimensional ground response analyses. It's a useful tool for checking the performance of QUAKE/W, since it is an independently developed product, and since it is based on a completely different formulation. Comparing results from these two products is a good way of validating the QUAKE/W formulation and implementation. This example gives the results of a comparison study for three different earthquake records.
The San Fernando earthquake occurred in California in 1971. The earthquake created a liquefaction failure at the Lower San Fernando Dam and Reservoir. This analysis demonstrates the advantages of using QUAKE/W with other GeoStudio products to analyze the multiple issues that arose with this case.
This example presents the results of a permanent deformation analysis of a low dam on a clay foundation. QUAKE/W is used to do a shaking analysis, and the results are then used in SIGMA/W to do a “Dynamic Deformation” type of analysis. The results are also compared with a Newmark-type of deformation analysis.
SLOPE/W is the leading slope stability software for computing the factor of safety of earth and rock slopes. SLOPE/W can effectively analyze both simple and complex problems for a variety of slip surface shapes, pore-water pressure conditions, soil properties, analysis methods and loading conditions.
SEEP/W analyzes groundwater flow within porous materials such as soil and rock. Its formulation enables analyses ranging from simple saturated steady-state problems to sophisticated saturated/unsaturated time-dependent problems.
SIGMA/W performs stress and deformation analyses of geotechnical, civil and mining works. It can perform a simple linear elastic deformation analysis or a highly sophisticated soil-structure interaction analysis with non-linear material models and coupling to seepage analysis.
QUAKE/W enables dynamic analysis of earth structures subjected to earthquake shaking, or point dynamic forces from a blast or a sudden impact load. It determines the motion and excess pore-water pressures that arise due to shaking.