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Today, Reinforced Concrete Frame with Buckling Restrained Brace (RCF-BRB) are commonly used as lateral resisting systems in seismic areas. Two characteristics of higher energy dissipation capacity and lack of buckling behaviour, has caused that RCF-BRB have a better alternative to conventional bracing. In this study, Seismic Analysis of RCF-BRB at far and near faults is investigated. Comparison of validation of BRB by ABAQUS software with laboratory model indicates acceptable agreement. In this paper, 3- and 5 story reinforced concrete frame with BRB were subjected to 6 earthquake scaled record, and roof displacement, base shear, force-displacement curve, and absorbed energy of the frame and its components were investigated. As well as stresses and plastic strain of frame components and BRB were also evaluated to find the causes of the weakness. The results showed that the far faults record has more destructive effects than the near faults record on the RCF-BRB and it was also found that the effective components in plastic deformation of BRB, are Core, and Gusset plate.

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The stability and lateral resistance of the Steel Plate Shear Wall (SPSW) is commonly used in earthquakes prone areas due to its high flexibility and energy absorption capacity in tall steel structures. Fire can significantly reduce the lateral resistance and stability of such structures. The purpose of this paper is to investigate the performance of Perforated Steel Plate Shear Wall (PSPSW) in the face of high temperatures. Therefore, 9 steel frames, each including one floor and one span, containing perforated steel plates, were numerically modelled and their behavioural characteristics were examined at high temperatures. Numerical results show that all seismic factors such as strength, stiffness and ductility in the lateral resistance and stability of Perforated Steel Plate Shear Wall (PSPSW) are reduced against high temperatures. Also, at high temperatures, it was found that before lateral loading, permanent plastic areas are formed, especially around the perforations, which increases the sensitivity of the system to the small earthquakes.

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A rigid plastic calculation method for predicting load versus maximum load pressures related to the formation of plastic hinges in the reinforced concrete (RC) beam on Winkler soil of foundation is proposed. The utility of the proposed method is to provide a simple calculation tool for hand calculation useful to predict the foundation’s bearing capacity and for verifying the over-strength of the soil-foundation complex. It is highlighted that the plastic resources of the soil-foundation complex depend not only on the characteristics of the soil, but also on the geometrical and mechanical characteristics of beam on foundation and the characteristics of the vertical load (intensity, eccentricity). The proposed method shows good agreement with numerical model developed with MIDAS Civil code. It is also shown that a maximum ratio of longitudinal steel bars should be adopted to ensure strength hierarchy with plasticization of RC beams before soil plasticization.

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To reasonably predict the seismic response of the liquid storage tank under different earthquake records, a new mechanical model is proposed based on the equivalent principle of the base shear and the overturning moment. Firstly, the velocity potential of the liquid in the storage tank is introduced by resolving the Laplace equation. Thereafter, the governing equations of motion of a liquid storage tank with base isolation are derived on the basis of Hamilton’s principle. And finally, the dynamic response processes of the liquid storage tanks of different ratios of height to radius by using the existing mechanical models, proposed mechanical model, and three-dimensional finite element model in the software ANSYS are compared. The analysis results show that the proposed mechanical model is stable and reliable whilst the predicted results are highly accurate and effective. Given the high order convective modes, the liquid sloshing height has a delayed effect.

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Nowadays, Buckling-Restrained Braced Frames (BRBF) are mainly used as lateral load-resisting systems in seismic areas. Two characteristics of higher energy dissipation capacity and lack of existence of buckling behavior have been caused that buckling-restrained brace to be a better alternative to conventional bracing. In this study, the response modification factor (R-factor) and other parameters of buckling of Reinforced Concrete Frame (RCF) with BRB bracing (RCF-BRB) have been investigated. The (R-factor) is a function of different parameters, which to determine these coefficients, the nonlinear static pushover analysis in accordance with ATC-19 and two methods of equal energy and Priestley & Paulay were used to evaluate the plastic behavior of RCF with and without BRB bracing. The result showed that the lateral stiffness of RCF-BRB decreases with increasing the number of stories so that in the number of high stories, the lateral stiffness of RCF-BRB becomes very close to the lateral stiffness of the RCF.

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A numerical campaign comparing the seismic behavior of cold-formed steel rack structures using both Nonlinear Static Analysis (NSA) and Incremental Dynamic Analyses (IDA) is presented. A total of 140 progressively scaled natural ground-motion records, along with 2 different forces distribution for NSA, were applied to a case study model build considering geometrical nonlinearity ( –  effects) and using proper elements to reproduce the pinching of beam-to-column joints in case of hogging and sagging bending moment. Data obtained from IDA were statistically processed and compared with the ones from NSA in terms of seismic vulnerability, specifically in terms of displacement demand and capacity, collapse spectral acceleration and proposing an appropriate damage index capable of tracking the state of the system as the spectral acceleration increase. Results show that NSA underestimates the displacement demand of the system and overestimates the collapse intensity measure (capacity spectral acceleration), thus not always being on the safe side.

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The study presents an experimental and numerical assessment of the Prestressed Lead Extrusion Damper (P-LED), an emerging energy dissipation device which provides energy dissipation through the plastic extrusion of lead, and achieves high specific output force by preloading of the working material. Tests are performed according to the European standard EN 15129. The damper shows a rigid-plastic behaviour with an essentially rectangular hysteresis loop, resulting in an effective damping of 0.55 regardless of the imposed deflection, and is able to sustain multiple cycles of deformation at the basic design earthquake displacement without degradation of the output, providing maintenance-free operation even in presence of repeated ground shakes. A 3D finite element model of the P-LED is formulated and used in a parametric study to investigate the influence of the device dimensions on the output force. The numerical data points are fitted by a simple model which can be used for designing the damper to a specified quasi-static force.

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Retrofit solutions conceived to have low-invasiveness, rapidity of execution and seismic capacity enhancement are of paramount importance in the perspective of Performance-Based Retrofit. Among the various retrofit techniques developed for existing reinforced concrete buildings, those based on the use of external additive walls seem to better satisfy such prerequisites.

This paper deals with a preliminary numerical study aimed at investigating the benefits provided by external post-tensioned rocking Cross-Laminated Timber (CLT) walls to an existing six-storey reinforced concrete building. To this aim, a design methodology based on the Displacement-Based Design which allows to determines the wall dimensions and the pre-stressing forces in the tendons has been herein proposed.

The effectiveness of the additional rocking CLT walls have been validated trough nonlinear static analyses, conducted on both as-built and retrofitted structure. Preliminary results, show that the retrofit intervention is beneficial in terms of seismic capacity increase, expected annual losses and reduction of the seismic risk class of the construction. Nevertheless, future studies based on a more accurate modelling are necessary to validate the results herein obtained and for defining technological solution the connections between framed structure and CLT walls.

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