Earthquake Disaster Scenario Predictions and Loss Modelling for Urban Areas

The overall aim of Sub-Project 10 (Earthquake disaster scenario predictions and loss modelling for urban areas) has been to create a tool, based on state-of-the-art loss modelling software, to provide strong, quantified statements about the benefits of a range of possible mitigation actions, in order to support decision-making by urban authorities for seismic risk mitigation strategies. A further larger aim has been to contribute to a seismic risk mitigation policy for future implementation at European level. Among the European cities for which loss estimation studies have been carried out are Istanbul, Lisbon and Thessaloniki, and tools, using GIS mapping, have been developed by research teams in each of these cities; these were made available for further development to examine mitigation strategies within SP10. Related research studies – on ground motion estimation, on the assessment of human casualties, and on the evaluation of uncertainty have been carried out by other research teams across Europe which includes INGV, UCAM and USUR respectively. In all three of the cities, a common general approach to loss modelling has been adopted which includes representing the earthquake hazard as a set of alternative ground motion scenarios (typically those with an expected recurrence periods of 50 and 500 years), and applying the ground motion over a target area of known population and building stock. Losses have then been estimated for this target area in terms of levels of building damage and human casualties expected both in the existing state of the target area, and after certain selected potential mitigation actions have been carried out. This has been done in each case using building stock classifications and vulnerability data specific to the particular city concerned. In each case the scope of the proposed mitigation action has been described, and its expected benefit in terms of reduced losses and human casualties has been determined with some preliminary assessment of uncertainty.

Probabilistic Methods for Seismic Assessment of Existing Structures

This self-contained document provides a presentation and illustration of two methods (one based on non-linear static analysis, the other on non-linear time-history analysis) for probabilistic seismic risk assessment of structures. The presented methods belong to a class which has been under development (mainly in the US) since more than a decade, and it is now firmly established and gaining wide international acceptance. The principal appeal of these methods is that they require only a limited background in probability and statistics. While they are presently directly usable for the assessment of existing structures, their extension for direct design purposes is currently under way. In order to facilitate the use of these methods the type and amount of information required for their application is also illustrated in this document. In particular, one chapter introduces the probabilistic representation, and evaluation, of the seismic hazard (PSHA) and the issue of selection and scaling of recorded ground motions for the purpose of dynamic analysis. A further chapter gives an overview of the most recent research aimed at developing models for the capacity (strength or deformability) of structural members and connections/joints in RC and steel structures. A detailed presentation of several case-studies illustrating the two approaches completes the document.

Guidelines for Displacement-based Design of Buildings and Bridges

Displacement-based seismic design has now come of age, especially for buildings. This report attempts to contribute to it, by focusing on special subjects which are crucial for its further advancement. It is divided in two Parts: one for buildings and another for bridges. Both parts have a chapter on the estimation of displacement and deformation demands and another on component force and deformation capacities.
For buildings, the part on analysis for displacement and deformation demands evaluates nonlinear analysis methods and the corresponding modelling at various degrees of sophistication, on the basis of experimental results (including identification of model parameters affecting reliability of deformation predictions) and compares nonlinear dynamic to linear analyses (static or modal) for irregular in plan buildings. It covers also soil- structure interaction in 3D, including uplift. It concludes with a description of the latest advances in adaptive pushover analysis for irregular buildings. Tools for the estimation of displacement and deformation demands are given, in the form of effective elastic stiffness of concrete members for use in linear analyses emulating nonlinear ones and of ductility-dependent equivalent damping. The chapter on component force and deformation capacities proposes acceptance and design criteria in terms of deformations at various performance levels, for concrete members in uni- or bi-directional cyclic loading.
The Part on bridges starts with an overview of displacement-based design methodologies for them, including evaluation of iterative procedures and proposals for the design of bridge piers directly on the basis of displacement and deformation demands, without analysis iterations. The chapter on estimation of displacement and deformation demands includes nonlinear analysis (static or dynamic), as well as the latest advances in adaptive pushover analysis for bridges. It also uses test results and numerical approaches to develop tools for the analysis, e.g., the secant-to-yield stiffness and the equivalent damping of concrete piers. The chapter on component force and deformation capacities focuses on concrete piers, developing simple rules for the estimation of their flexure- or shear-controlled cyclic ultimate deformation, on the basis of test results and numerical analyses. It also has a part devoted to seismic isolators, dealing with the evaluation of their displacement and re-centring capacity and the effect of exceedance of isolator displacement capacity on the bridge seismic response. The effect of the variation of the axial force of friction pendulum isolators on the response of the isolated bridge is also studied.

Pile Design and Installation Using Ultimate Design Methods

Bentley PondPack 08.11.01.54 V8i

(30 days trial and renew)

Tested in Windows 7 x64 using the crack posted in Lavteam by Istigatore. The registry patch transform the software to Trial Unlimited Size but after 30 days the trial expire. I added a file (BentNew.exe). Running it will restore the 30 days trial. And by the way it will restore the trial period for almost every Bentley trials posted here.

Bentley CivilStorm V8i SELECT Series 2 08.11.02.65 (30 days trial and renew)

Tested in Windows 7 x64 using the crack posted in Lavteam by Istigatore. The registry patch transform the software to Trial Unlimited Size but after 30 days the trial expire. I added a file (BentNew.exe). Running it will restore the 30 days trial. And by the way it will restore the trial period for almost every Bentley trials posted here.

Guidelines for Seismic Vulnerability Reduction in the Urban Environment

This report deals with the reduction of the seismic vulnerability of buildings and infrastructures. This can correspond to very different interventions, as there are many types of structures, many materials and many ways to reduce vulnerability. This explains that a variety of topics is treated.
The first chapter deals with the screening of buildings on an urban scale to identify which need retrofitting. In the second chapter, conventional methods for retrofitting are described.
In all the following chapters, new techniques for retrofitting are presented. The application of Fibre Reinforced Polymers (FRP) on existing structures is a technique which has developed a lot recently. The content of Chapter three is related to the design of FRP solutions: a user friendly design tool, experimental data on durability and fatigue and a design method considering the contribution of steel rebars and FRP to resistance. An effective numerical model for composite is presented. Chapter three also describes experimental studies on masonry infill which FRP can effectively reinforce against transverse move and for their in-plane strength. Rehabilitation using that technique can be applied at an urban scale. The use of dissipative devices to reduce the vulnerability of structures is the subject of Chapter four. The technique is applied to precast concrete portal frames and to steel frames with concentric bracings. The use of base isolation for seismic upgrading of historical buildings is developed in Chapter five, in which a displacement - based method is applied to a light house. The mitigation of hammering between buildings, with a methodology to face various situations, is the subject of Chapter six. A displacement based methodology of analysis for underground structures in soft soils is presented at Chapter seven. This Report focuses on practical applications rather than on theory.