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This article presents the findings of a study on the directionality effect observed in strong motion records. We set out to establish ratios between several seismic intensity measures that depend on sensor orientation (e.g., GMar, Larger) and others that are orientation-independent (e.g., RotDpp, GMRotDpp, and GMRotIpp), with the intention of proposing multiplicative correction factors. The analysis included an evaluation of the impact of site conditions, ground motion intensity, earthquake magnitude, and hypocentral distance on these ratios. Following a concise overview of the directionality effects and the associated intensity measures, the Costa Rican Strong Motion Database, comprising a total of 4199 horizontal accelerograms (two components), was employed to determine the correction factors. The analysis was carried out for 5% damped response spectra within the 0.01–5 s period range. The study focuses on orientation-independent intensity measures that are derived by combining the maximum values from the recorded motions. In the comprehensive analysis of the complete database, a trend was observed between these intensity measures and the magnitude of the earthquake along with the hypocentral distance. Specifically, records from earthquakes with greater magnitudes exhibited a lower maximum spectral response to the geometric mean of the response spectra of the as-recorded (ar) components ratio (RotD100/GMar), similar to records from earthquakes with larger hypocentral distances. Based on these findings, a proposal was put forth to estimate RotD100 values using GMar values. This ratio can prove useful in transforming data from previous seismic hazard studies, including those applied in many seismic codes, and in defining the maximum anticipated seismic intensity for design purposes in a more straightforward manner. [ABSTRACT FROM AUTHOR]

In this paper, the soil profile of the Costa Rican Strong-Motion Network (CRSMN) stations is classified based on actual measurements and seismic regulations. The soil classification of the Costa Rican Seismic Code based on the average shear-wave velocity of the top 30 m (VS30) is used as a reference. The site fundamental period (Tf) is included as a parameter to complement the existing characterization. For this, VS30 measurements from 52 accelerometric stations are related to the site fundamental period obtained through horizontal-to-vertical spectral ratios (HVSR) using ground motion records from the Costa Rican Strong-Motion Database. The H/V ratios are estimated with 5% damped acceleration response spectra and with traditional Fourier amplitude spectra from the S-wave window. From the relation between VS30 and Tf, different ranges of Tf are assigned to the existing soil profile classification and a graph with three-lines and four-areas is proposed to classify the stations of the CRSMN. These lines are plotted from the intersection between values assigned to each site class. The assigned classification at each station will be the one corresponding to the area where the pair of values (VS30 - Tf) falls. With this proposal, both parameters take relevance and are compensated, reducing the differences due to possible errors in measurements or interpretations. [ABSTRACT FROM AUTHOR]

• CPG-RM walls exhibit a semi-brittle behavior under lateral loads. • The collapse mechanism is influenced by the aspect ratio. • Evaluated shear prediction equations for RM are conservative. • The contribution of RC columns in shear equations must be considered as a masonry column. This article presents the experimental results and analysis of five full-scale walls subjected to in-plane reversed cyclic displacements. All walls were constructed with reinforcement in both vertical and horizontal directions and, with a reinforced concrete frame in the perimeter of the wall as confinement. This research focuses on the effect of different aspect ratios of the walls on shear response. Force versus displacement diagrams and failure modes allowed the assessment of the seismic performance based on the stiffness degradation, ductility, drift capacity, and dissipated energy. An influence on the stiffness degradation derived from the aspect ratio was found. Ductility and equivalent viscous damping seem not to be affected by aspect ratio variations. The shear capacity is overestimated when the contribution of RC columns is explicitly considered. Using an equivalent masonry element instead of the reinforced concrete column gives a more conservative and realistic approach to the shear capacity. [ABSTRACT FROM AUTHOR]

• Probabilistic modeling of hazard and exposure is paramount for estimating seismic risk. • The proposed model captures well the seismic response of RCMW structures. • Laboratory test validate the random mechanical properties of the structural models. • Similar seismic damage values are obtained despite the nonlinear analysis employed. • PG-RCMW structures exhibit an adequate performance in earthquake-prone areas. In Costa Rica, typical dwelling constructions are generally built with reinforced concrete masonry walls. This construction practice became one of the most common during the second half of the last century in Costa Rica. These kinds of structures exhibit high lateral stiffness and shear capacity, which makes them susceptible to semi-ductile failure or torsion if they are not correctly designed and constructed or the walls are not well distributed. However, recent research has shown that this type of masonry exhibits adequate capacity to dissipate plastic energy if the latter requirements are controlled. In this study, the seismic behavior of a recently designed and built reinforced concrete masonry structure is studied from a probabilistic perspective. Experimental results have been used to calibrate the probabilistic model. This structure was designed using the response spectrum method according to the Costa Rican Seismic Code. To verify its expected behavior considering more advanced analysis, it is analyzed through probabilistic incremental nonlinear static and dynamic computational-based methods. The aim is to obtain probabilistic damage curves in a series of permutations between the mechanical properties and the nonlinear behavior of the walls. Three different Damage Indices are estimated. Specifically, the Park & Ang damage index is used as a reference for two approximations that employ the capacity curve as input. Results indicate that the behavior of the analyzed structure is suitable for the seismic demand provided by the Costa Rican Seismic Code. Finally, correlations between input and output variables are calculated to analyze what are the variables governing the structural response. A strong relationship between masonry compression strength, Young's module, and the post yielding slope (input variables) and all the output variables has been observed. [ABSTRACT FROM AUTHOR]