Journal of Earthquake Engineering

In the present paper a rational mechanical based approach for the seismic capacity assessment of classes of buildings is presented and capacity curves in terms of ultimate strength and deformation capacities are derived. The proposed procedure allows the main parameters (morphologic and geometric configuration, mechanical properties etc.) to be chosen and their relative influence on the capacity of RC buildings to be evaluated. This evaluation is helpful, since it permits, in the framework of vulnerability assessment at a regional or sub-regional scale, to have a measure of the error that is related to the amount of the information available. Consequently, depending on the relative influence of parameters on response, and also considering the different type of parameters and related availability (by public databases for low order parameters, or by field survey for high order ones), a multilevel building class specification in function of input variables is proposed.

Northwestern Italian weak-motion data were used to study attenuation characteristics of horizontal peak ground acceleration (PGA) and horizontal peak ground velocity (PGV) from earthquakes of local magnitudes (M_l) up to 5.1. Data have been provided by the RSNI (Regional seismic network of Northwestern Italy) and RSLG (Regional seismic network of Lunigiana-Garfagnana) waveform database. The database consists of more than 14 000 horizontal components recorded in the period 1999–2002 by both broadband and enlarged band seismometers. The accuracy of the procedure used to extract PGA values from the velocity recordings was verified comparing observed and derived PGA values at station STV2, which was equipped with both a temporary K2 Kinemetrics accelerometer and Guralp CMG40 broadband sensor. The attenuation of both peak ground acceleration and peak ground velocity was found to be logarithmically distributed with a strong attenuation for low distances (less than 50 km) and low M_l values (<3.0). The resulting equations are:

In this paper, the damage prediction of shear-dominated reinforced concrete (RC) elements subjected to reversed cyclic shear is presented using an existing damage model. The damage model is primarily based on the monotonic energy dissipating capacity of structural elements before and after the application of reversed cyclic loading. Therefore, it could be universally applicable to different types of structural members, including shear-dominated RC members. The applicability of the damage model to shear-dominated RC members is assessed using the results from reversed cyclic shear load tests conducted earlier on eleven RC panels. First, the monotonic energy dissipating capacities of the panels before and after the application of reversed cyclic loading are estimated and employed in the damage model. Next, a detailed comparison between the analytically predicted damage and the observed damage from the experimental tests of the panels is performed throughout the loading history. Subsequently, the effects of two important parameters, the orientation and the percentage of reinforcement, on the damage of such shear-dominated panels are studied. The research results demonstrated that the analytically predicted damage is in reasonably good agreement with the observed damage throughout the entire loading history. Furthermore, the orientation and percentage of reinforcement is found to have considerable effect on the extent of damage.

This paper presents the results of an experimental and numerical investigation on the behaviour of U-shaped walls subjected to lateral uniaxial and biaxial cyclic loading. The test specimens have been sized and detailed according to EC8 code. The tests aimed at studying the behaviour of a full scale U-shaped wall in uniaxial and biaxial bending and shear, and compared the alternative design requirements of two versions of EC8. A 3D multilayer thin shell finite element formulation, incorporating a concrete model with a smeared cracking capability, was used to simulate the experimental behaviour of this specimen. Comparison between numerical and experimental results shows that the model is capable of predicting with acceptable accuracy the most important characteristics of the measured global and local response. Based on the findings of both experimental and numerical results, some additional recommendations for design and analysis have resulted.

In this paper, a detailed description of the analytical modelling of a full-scale irregular RC test structure intended for Pseudo-dynamic (PsD) testing is presented. Extensive pre-test assessment was performed to investigate the capacity and dynamic characteristics of the test structure. The use and applicability of static and dynamic analysis methods are discussed. A systematic approach to determine an earthquake scenario for the highly irregular test model was developed which satisfies three criteria: (i) collapse prevention, (ii) severe damage level for the acquisition of data on structural damage and (iii) maximum torsional response. Four pre-test models with different assumptions were compared in addition to the comparison of analytical and experimental results.

The importance of local site amplification during historical earthquakes in Eastern Venezuela is documented by setting the information in its geological and historical context. Reports are often only available for a few urban spots settling on soft soils. Prior to the second half of the 20th century, historical information is only available for the Northern Caribbean coast. During the following years, the increase in the number of villages inside the Orinoco basin results in a better description of historical earthquakes. An assessment of intensity values using the descriptions of the damages suffered by religious and military buildings is often unavoidable, because information on the damages suffered by individual houses is often lacking. This constraint requires us to understand the architectural characteristics of the buildings and the history of their repairs. Due to their peculiar geometry, material heterogeneity, and long lasting repairs, the vulnerability of the buildings could indeed be higher than the vulnerability of individual houses. The settlement of forts on top of the steep hills surrounded by soft water-rich soils still enhanced their vulnerability, due to the low-frequency amplification of the ground motion.

Japan has twenty years of experience in designing and constructing base-isolated building structures. Construction has increased significantly since the 1995 Hyogoken-Nanbu (Kobe) earthquake, having reached over 150 annual construction projects. Many new developments and refinements have been made in the material, device, design, and construction of these structures. This paper summarises recent design and construction of base-isolated building structures in Japan, including statistical data with respect to the common usage as well as the number of new projects. It is notable that the size, height, and fundamental natural period of new base-isolated buildings increase steadily with time, indicating that base-isolation in Japan is reaching maturity. Base-isolators and dampers commonly adopted in Japan are also introduced, with emphasis on recent design efforts to enlarge the natural period of base-isolated structures and reduce the lateral forces induced in the superstructure. Basic design procedures are presented, including determination of design earthquake forces, modelling of base-isolation layers, modelling of the superstructure, selection of ground motions, time-history analyses, and performance criteria. A mandated peer-review system, unique for design of base-isolated structures, is also noted. Several characteristic issues in the design of base-isolated structures are discussed: Variation of base-isolation material properties, applications to high-rise buildings, effects of vertical ground motions, and response when subjected to near-fault ground motions.