Earth and Planetary Sciences (miscellaneous)

In situ free-vibration tests on unrestrained and restrained rocking masonry walls

In the out-of-plane assessment of rocking walls, a relevant and yet uncertain aspect is the influence of energy dissipated during motion due to impacts and restraints, such as a floor or tie rods. Therefore, in situ rocking tests on unrestrained and restrained unreinforced masonry walls, made of composite (rubble + blockwork) masonry, were performed and analyzed. The restraint is given by steel springs of assigned stiffness, simulating a floor connected to full-scale (4 × 1 × 0.6 m3) specimens from a dismantling building.

Evolution of out-of-plane deformation and subsequent instability in rectangular RC walls under in-plane cyclic loading. Experimental observation

In this study, to understand the causes and consequences of out-of-plane instability in rectangular RC walls, the sequence of events observed during a rectangular wall experiment campaign where out-of-plane instability was the primary failure pattern is discussed in detail. Large tensile strains developed in the boundary zone longitudinal bars at large in-plane curvature demands and caused subsequent yielding in compression during load reversal before crack closure could activate contribution of concrete to the load-carrying capacity of the wall.

Improved risk-targeted performance-based seismic design of reinforced concrete frame structures

This paper presents a procedure for seismic design of reinforced concrete structures, in which performance objectives are formulated in terms of maximum accepted mean annual frequency (MAF) of exceedance, for multiple limit states. The procedure is explicitly probabilistic and uses Cornell's like closed‐form equations for the MAFs. A gradient‐based constrained optimization technique is used for obtaining values of structural design variables (members' section size and reinforcement) satisfying multiple objectives in terms of risk levels.

An evaluation of the potential of Sentinel 1 for improving flash flood predictions via soil moisture-data assimilation

The assimilation of satellite-derived soil moisture estimates (soil moisture-data assimilation, SM-DA) into hydrological models has the potential to reduce the uncertainty of streamflow simulations. The improved capacity to monitor the closeness to saturation of small catchments, such as those characterizing the Mediterranean region, can be exploited to enhance flash flood predictions. When compared to other microwave sensors that have been exploited for SM-DA in recent years (e.g.

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