Unreinforced masonry (URM) construction, which has been widely used in the United States, presents a large threat to life safety and regional economic development because of its poor seismic resistance. In this research, the nonlinear seismic properties of URM structures were investigated via a quasi-static test of a full-scale two-story URM building and associated analytical and numerical studies. The tests of the 24ft. by 24ft. in plan 22ft. high URM building revealed that the damage was characterized by (1) the formation of large discrete cracks in the masonry walls and (2) the rocking and sliding of URM piers. Both of these results were consistent with the predictions based on individual component properties obtained in previous research. However, the tests also revealed significant global behavior phenomena, including flange effects, overturning moment effects, and the formation of different effective piers in a perforated wall. This global behavior greatly affected the response of the URM building tested. In order to understand the nonlinear behavior of the test structure, a series of analytical studies were conducted. First, at the material level, a mechanical key model was proposed to describe the failure of URM assemblages under a biaxial state of stress. Second, at the component level, an effective pier model was developed to illustrate the mixed failure modes of a URM pier and its nonlinear force-deformation relationship. Third, at the structure level, a nonlinear pushover model was built using the mechanical models at the material and component levels to describe the nonlinear properties of a URM building. This nonlinear pushover model and a three-dimensional finite element model were employed to analyze the test structure. Both gave results in good agreement with the test data. Improvements to current provisions for the evaluation of existing masonry structures were proposed.

This book assembles, identifies and highlights the most recent developments in Rehabilitation and retrofitting of historical and heritage structures. This is an issue of paramount importance in countries with great built cultural heritage that also suffer from high seismicity, such as the countries of the eastern Mediterranean basin. Heritage structures range from traditional residential constructions to monumental structures, ancient temples, towers, castles, etc. It is generally recognized that these structures present particular difficulties in seismic response calculation through computer simulation due to the complexity of the structural system which is, generally, inhomogeneous, with several contact problems, gaps/joints, nonlinearities and brittleness in material constituents. This book contains selected papers from the ECCOMAS Thematic Conferences on Computational Methods in Structural Dynamics & Earthquake Engineering (COMPDYN) that were held in Corfu, Greece in 2011 and Kos, Greece in 2013. The Conferences brought together the scientific communities of Computational Mechanics, Structural Dynamics and Earthquake Engineering in an effort to facilitate the exchange of ideas in topics of mutual interest and to serve as a platform for establishing links between research groups with complementary activities.

"This project was carried out to find efficient retrofitting technique under blast loading by developing numerical material models. It was based on experimental research of strengthening URM walls by using retrofitting technologies under out-of-plane loading at the University of Adelaide. The numerical models can be applied to study large-scaled structures under static loading, and the research work is then extended to the field of blast loading. To study the increasing capability in strength and ductility of retrofitted URM walls, pull-tests were simulated using interface element model to investigate the bond-slip relationship of FRP plates bonded to masonry blocks. The interface element model was then used to simulate performance of retrofitted URM walls under static loads. The accuracy of the numerical results was verified by comparing with the experimental results from previous tests at the University of Adelaide by Griffith et al. (2007) on unreinforced masonry walls and by Yang (2007) on FRP retrofitted masonry walls. To study the de-bonding behaviours of retrofits bonded to masonry, and find appropriate solution to protect certain masonry walls against blast loading, various retrofitting technologies were examined. The simulation covers explosive impacts of a wide range of impulses. Based on this work, pressure-impulse diagrams for different types of retrofitted URM walls were developed as a design guideline for estimating the blast effect on retrofitted masonry walls." -- From abstract.

This text provides a basis for a standardized approach to structural masonry, using an integration of experimental and computational techniques. Accurate displacement-controlled materials experiments have produced an extensive database of strength, stiffness and softening properties for tension, compression and shear, and this data has been transferred into numerical models for simulating the deformational behaviour of masonry structures. The models have been implemented into finite and distinct element codes and have subsequently been verified against shear wall experiments and analytical solutions for masonry parts.

This text provides a basis for a standardized approach to structural masonry, using an integration of experimental and computational techniques. Accurate displacement-controlled materials experiments have produced an extensive database of strength, stiffness and softening properties for tension, compression and shear, and this data has been transferred into numerical models for simulating the deformational behaviour of masonry structures. The models have been implemented into finite and distinct element codes and have subsequently been verified against shear wall experiments and analytical solutions for masonry parts.

Numerical Modeling of Masonry and Historical Structures: From Theory to Application provides detailed information on the theoretical background and practical guidelines for numerical modeling of unreinforced and reinforced (strengthened) masonry and historical structures. The book consists of four main sections, covering seismic vulnerability analysis of masonry and historical structures, numerical modeling of unreinforced masonry, numerical modeling of FRP-strengthened masonry, and numerical modeling of TRM-strengthened masonry. Each section reflects the theoretical background and current state-of-the art, providing practical guidelines for simulations and the use of input parameters. - Covers important issues relating to advanced methodologies for the seismic vulnerability assessment of masonry and historical structures - Focuses on modeling techniques used for the nonlinear analysis of unreinforced masonry and strengthened masonry structures - Follows a theory to practice approach