{"id":7710,"date":"2022-05-16T14:07:47","date_gmt":"2022-05-16T14:07:47","guid":{"rendered":"https:\/\/blog.geostru.eu\/?p=7710"},"modified":"2022-05-24T18:54:49","modified_gmt":"2022-05-24T18:54:49","slug":"drew-seismic-displacement-of-retaining-walls-due-to-earthquakes","status":"publish","type":"post","link":"https:\/\/blog.geostru.eu\/en\/drew-seismic-displacement-of-retaining-walls-due-to-earthquakes\/","title":{"rendered":"DReW Seismic: Displacement of Retaining Walls due to Earthquakes"},"content":{"rendered":"

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Stability analysis of embedded cantilever retaining walls in seismic area is generally carried out by calculating a factor of safety against a possible mechanism of collapse. However, a more rational approach consists in assessing the performance of the structure in terms of accumulated permanent displacement (Fig. 1). Indeed, this approach is required by many national standards as well as Eurocode 8 Part 5<\/a> (\u00a77.1(1)P; \u00a77.1(2)). However, the effectiveness of a performance-based approach is strongly related to the ability of the employed method to assess the earthquake-induced displacements of the structure. In this context, the Newmark\u2019s method, which is commonly employed for the assessment of the permanent displacement of gravity retaining walls due to earthquake, generally leads to inadequate results when it is applied to embedded retaining structures, as both numerical and experimental studies have shown. Advanced numerical methods, such as FEM and FDM, can definitely provide a satisfactory comprehension of the performance of embedded retaining walls under seismic conditions. However, the employment of such methods for routine applications is still impracticable for the difficulty of handling complex constitutive models, which require a large number of parameters of difficult determination.<\/p>\n

In this context, DReW Seismic<\/strong><\/a>\u00a0is a software which allows readily evaluating the permanent displacement of embedded cantilever retaining walls, such as diaphragm or sheet-pile walls, after an earthquake. It is based on a method, of simple application, that performs the prediction of the permanent displacement of the top of the wall owing to a given seismic event. DReW Seismic<\/strong>\u00a0is simple to use and requires a limited number of input parameters. In addition, a database of acceleration time-histories is provided. These aspects make the software quite attractive for practical applications. DReW Seismic<\/strong>\u00a0is developed on the basis of the method recently published by Conte, Pugliese and Troncone (2022)<\/a> in the journal G\u00e9otechnique<\/em>.<\/p>\n

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To calculate the wall displacement due to the earthquake, DReW Seismic<\/strong> compares the ground acceleration time-history with the critical threshold, which is updated during the earthquake to account for the progressive development of the passive resistance of the soil. When the ground acceleration exceeds the critical threshold, the motion equation is solved to calculate the angular acceleration of the wall. Once this latter is known, angular velocity and rotation (\u03b8) of the wall are calculated by successive integration. Finally, the displacement of the top of the wall (u<\/em>) is calculated under the assumption that the wall rotates rigidly around a point located close to its base (Fig. 1). A schematic representation of the above described integration procedure is shown in Fig. 2.<\/p>\n

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GENERAL FEATURES IN DReW SEISMIC<\/h3>\n

DReW Seismic<\/strong>\u00a0performs a seismic analysis<\/em> of embedded cantilever retaining walls in cohesionless soils, calculating the evolution with time of the permanent displacement of these structures owing to earthquakes. The seismic analysis<\/em> refers to the solution developed by Conte, Pugliese and Troncone (2022)<\/a>. The main features of the software are listed below:<\/p>\n