Current Issue : October-December Volume : 2021 Issue Number : 4 Articles : 5 Articles
The aim of the research is to analyze the approaches to the problems of functional and structural rehabilitation of historic monumental buildings. The research examined the possibility of changing the destination of a historic building, which involves both functional rehabilitation (rehabilitation and adaptation of thermal energy, acoustics, water repellent and fire protection) and structural rehabilitation, by replacing or partially modifying the building or, if the structural system allows, complete restoration of its parts; local structural restoration (consolidation); structural modification, by introducing adjacent or incidental construction elements, which together with the existing structure can form another structural system and even change the structural concept using the procedures that can increase strength and stability. As a result of the research, it was established that changing the destination of a building involves both functional rehabilitation, by compartmentalizing the new function, rehabilitation and thermal, energy, acoustic, water repellent adaptation and fire safety of the building undergoing reconversion, and structural rehabilitation. When protecting historical monuments, a series of principles and rules must be observed regarding the owners’ interventions, the holders of the administration right, the concessionaires and the tenants....
+e aim of this paper is to assess the structural behavior of hybrid thin-walled beams which were fabricated using laminated carbon fiber reinforced polymer (CFRP). Seven hybrid (CFRP) I-beams were fabricated, instrumented, then have been tested under monotonic four-point loading in order to evaluate their behavior up to failure. In constructing the I-beam specimens which were evaluated in this study, plywood core was implemented on both the web and flanges. Several important parameters were conducted in this study considering changing both of the ply orientations and stacking sequences of laminated fibers, also changing the shear span-to-depth ratio (a/d) of the specimens. +e experimental results showed that stacking sequence is the most significant parameter that influences both flexural strength and stiffness of the hybrid beams. Also, the experimental results promoted the effectiveness of the core material for enhancing the flexure (bending) stiffness of beams. +en, these results were compared with a previous simulated study which used the finite element modeling to model the beams. Also, in order to evaluate the efficiency of the CRFP beams, the results were compared to similar steel beams having the same dimensions of the CFRP beams. As compared to steel beams, the load carrying capacity of the laminated beams is being high compared with steel beams when taking into consideration their specific strength ratio....
Heavy duty riveted gratings are a good alternative for applications that often employ other deck systems, if they are carefully analyzed under static and fatigue loads. Understanding the static behavior of a riveted steel deck under tire patch loads will aid in establishing a design model based on an effective beam width. In addition, use of a riveted system avoids welded details that may lead to fatigue cracking, thereby improving design life. In this study, analysis of a typical riveted steel deck under a standard AASHTO fatigue truck with a 15% impact factor was conducted. Hand calculations were compared with the results of a finite element model using SAP2000 v19.2.1. Bending moments and stresses were evaluated and compared. Stresses at the rivet hole for the most highly loaded bearing bar were evaluated. A model for fatigue cracking around a rivet hole is discussed....
Steel structures are usually damaged by disasters. According to the influence law of the damage on the elastic modulus of steel obtained by the mechanical test of damaged steel, the average elastic moduli of H-section steel members were analyzed. )e equations for calculating the average elastic moduli of damaged H-section steel members at different damage degrees were obtained. By using the analytical cross-sectional method, the cross-sectional M-Φ-P relationships and the dimensionless parameter equations of the H-sections in the full-sectional elastic distribution, single-sided plastic distribution, and double-sided plastic distribution were derived. On the basis of the cross-sectional M-Φ-P relationships and dimensionless parameters of actual steel members, the approximate calculation equations for the damaged cross sections were obtained. )e Newmark method was used to analyze the deformation of damaged steel columns. Analytical results show good agreement with the test results. )e equations and methods proposed in this study have high computational accuracy, and these can be applied to the cross-sectional M-Φ-P relationships and deformation calculation of damaged steel members....
During earthquakes, buildings are subjected to loads well beyond their usual demands, resulting in high stresses in the structural components and additional inertial forces coming from the non-structural elements. When post-installed anchors are used to form the connection between non-structural or structural members and the primary reinforced concrete structure, these anchors are also subjected to high seismic demands. To determine whether a post-installed anchor is suitable for such applications, it is assessed for its performance under seismic demands. In this review paper, the current European approach for testing and qualification of post-installed anchors under seismic actions is reviewed and discussed in the context of structural applications where anchors are used to form the connection between structural members that participate in the load-transfer mechanism against seismic loads. The first part of this paper provides a description of the testing procedures and the criteria against which the anchor performance is assessed. The procedures and assessment criteria are discussed regarding the suitability in the case of the above-described structural applications. In the second part, the qualification of anchors under seismic actions is discussed in the light of an upcoming performance-based design approach for anchors. In such an approach, information on the displacement and hysteretic behavior of an anchor in a broader range of the load–displacement curve is of vital importance. Therefore, additional testing approaches might be required in order to supplement the information on anchor performance provided in the current testing procedures. One such testing approach for pulsating tension load is reported....
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