Aspects on the masonry structural walls computation |
Author : Robert Draghici, Ana Maria Pârvanu?, Daniel Stoica |
Abstract | Full Text |
Abstract :The Romanian code CR6-2013, starting from EC6, proposes 3 types of structural masonry walls, which can be used for buildings with masonry resistance structure. This article aims to identify the answers of these types of walls, for different levels of axial forces NEd and dimensions of structural walls |
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Numerical Modeling for Engineering Analysis, Designing and Monitoring of Support Systems for Twin-Tube Tunnel |
Author : Houssam KHELALFA, U.SAKALLI, E. B. AYGAR, O.SIMSEK, B. AYKAN, H. BOULMAALI |
Abstract | Full Text |
Abstract :In this research work, Rock Mass Rating (RMR) was used for the characterisation of rock mass along the tunnel alignment based on physical, geological and geotechnical data of the project area. The support systems were recommended for all geotechnical units using RMR and tunneling quality index (Q-system) support chart. Furthermore, Various design
input parameters such as physical and geotechnical properties, in situ stresses, modulus of deformation of rock mass, support systems recommended by RMR were used as input parameters in Phase2 2D 8.0 software, in order to compare the calculation results with insitu monitoring using Amberg Tunnel 2.0 software, to validate the numerical models and to check the deformations of the tunnel in the temporary support stage. |
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Experimental and Numerical investigation on the effect of CFRP straps with different orientation angles on the strength of the beam |
Author : Gandla Nanabala Sreekanth, S.Balamurugan |
Abstract | Full Text |
Abstract :Now a days all the civil engineering structures are designed earthquake resistant to withstand the high intensity earthquakes that are occurring more frequently. But there is
a need to strengthen the already existing structures to withstand for earthquakes. Usage of CFRP sheets is a technique to strengthen a structural member of a structure to
withstand for natural occurring calamities.
This study presents the experimental and numerical investigation on the effect of CFRP sheets with varying angles of straps on the strength of the beam. The objective of this
work is to explore the behaviour of RC beam strengthened with CFRP sheet and straps.
Numerical analysis was carried out using software to represent the ultimate load vs deflection and ultimate load carrying capacity of the beam.
Comparison of experimental with numerical results exhibited, that beam strengthened with angled straps showed more effective in enhancing the deflections, failure modes and
ultimate strength of the RC beam. The strength of CFRP straps with different orientations were analyzed and compared. |
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Porous thermal insulation building material made of recycled glass waste by microwave heating |
Author : Lucian Paunescu, Sorin Mircea Axinte, Bogdan Valentin Paunescu, Felicia Cosmulescu |
Abstract | Full Text |
Abstract :The paper presents experimental results obtained in manufacturing process of cellular glass using the indirect microwave heating. The microwave absorption intensification was achieved using a silicon carbide crucible having the wall coated with a yttrium oxide film. The microwave heating and the use of yttrium oxide are the paper originality. The recipe containing glass waste, ash and silicon carbide allowed cellular
glass production at 960-970 ºC with economical energy consumption (below 0.86 kWh/kg). The products have specific characteristics of cellular glass with density between
0.27-0.33 g/cm3, thermal conductivity between 0.064-0.073 W/m·K, and compressive strength between 1.35-1.45 MPa. |
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Regarding the coupling beams in the calculation of the masonry walls |
Author : Robert Draghici, Ana Maria Pârvanu?, Daniel Stoica |
Abstract | Full Text |
Abstract :Masonry walls normally work connected either by floor slabs, by coupling beams made from masonry, reinforced concrete or by composite sections (masonry and reinforced concrete, etc.). The behavior of the coupling beams, including in the current design codes, is insufficiently approached, known and treated. For this reason, the indirect effect of the walls from the coupling beams is insufficiently known - most designers (due to lack of
information) prefer not to consider them in the overall calculation. After the tests performed on seismic masses on 3D models, but also after the major, real earthquakes, one
can easily see the special influence of the coupling beams on the overall behavior of the structural masonry walls (cantilevers or piers type). All bout these both for structural or partition or for normal and blind walls. Because these data are insufficiently well known in design practice, this study attempts to show how by using the ETABS program, for either dissipated energy or distortion energy, we can get sufficiently suggestive indications about the behavior of coupling beams as well as masonry walls |
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Non-linear numerical study of the dynamic response of elevated steel conical tank under seismic excitation |
Author : Nasser Dine Hadj Djelloul, Mohamed Djermane, Noor Sharari |
Abstract | Full Text |
Abstract :Elevated cylindrical and conical steel tanks are widely used to conserve water or chemical liquids. These important structures are required to stay protected and operative at any time. The wall angle inclination of conical tank part,as well as the presence of the vertical earthquake component, can cause damage to this structure and even lead to its failure.
The purpose of this study is to examine the effect of the wall angle inclination of the tank and the vertical earthquake acceleration component on the nonlinear dynamic stability of
the elevated steel conical tanks under seismic excitation. The elevated steel conical tank is simulated utilizing the finite element analysis method using ANSYS software. The
fluid-structure interaction is considered using a suitable interface that allows the fluid to apply hydrodynamic pressures on the structure. Three different models, namely Model –
A-30°, Model –B-45°and Model –C-60°were investigated; it has been concluded that the impact of inclination of the tank wall significantly affects the nonlinear stability of the elevated steel conical tank. While considering the vertical ground acceleration, inclination plays a significant role in the design of this type of structures. Therefore, it should be appropriately included in the seismic analysis of elevated steel conical tanks to satisfy the
safety of the elevated steel conical tank response under seismic loading |
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