Papers by Keyword: In-Plane Loading

Abstract: Moderate to strong earthquakes can cause considerable damage to masonry walls which are primary structural elements for decades. In previous earthquakes, a large number of masonry walls failed due to insufficient shear strength with excessive in-plane deformation, or due to insufficient out-of- plane bending capacity of the walls in the perpendicular direction. Typically, out-of- plane failure is far more prevalent and happens earlier than in-plane failure in most past earthquakes. Thus their arises the need to strengthen this masonry walls. Generally, the compressive forces that masonry walls bear vary at different storey’s vary , therefore, walls at lower storey’s can only be applied with relatively smaller prestress due to already higher compression stresses produced by self-weight and floor dead load. Many strengthening methodsSuch as using NSM-CFRP, post tensioning, shortcreting etc. are excellent methods of strengthening masonry walls. In this the performance of post tensioned and reinforced masonry walls is analyzed. Ungrouted, partially grouted, and fully grouted Post Tensioned [PT] Masonry Walls exhibit different behavior and failure mechanisms. For this an analytical model based on an experimental study is prepared and their results are compared with ABAQUS.

Abstract: Three unknown coefficient weight functions for eccentric through cracks in a 3-D rectangular plate subjected to in-plane loading are proposed. 3-D finite element models of cracked rectangular plates within the whole range of crack aspect ratios, i.e., 0≤e/W≤0.8, 0.08≤a/(W-e)≤0.9, were established to obtain a reference SIF database for both crack points A and B, rather than 2-D finite element models. To improve the accuracy of the weight function, the coefficients were derived from this database using the Binary Lagrange Interpolation Method instead of Curve-Fitting Expression. Comparisons of stress intensity factors calculated using the present weight functions with finite element data for the high-order power law and residual stress distributions show high accuracy of the present weight functions.

Abstract: Impact is one of very important subjects which always have been considered in mechanical science. Nature of impact is such that which makes its control a hard task. Therefore it is required to present the transfer of impact to other vulnerable part of a structure, when it is necessary, one of the best method of absorbing energy of impact , is by using Thin-walled tubes these tubes collapses under impact and with absorption of energy, it prevents the damage to other parts. Purpose of recent study is to survey the deformation and energy absorption of tubes with different type of cross section (rectangular or square) and with similar volumes, height, mean cross section, and material under loading. Lateral loading of tubes are quasi-static type and beside as numerical analysis, also experimental experiences has been performed to evaluate the accuracy of the results. Results from the surveys is indicates that in a same conditions which mentioned above, samples with square cross section ,absorb more energy compare to rectangular cross section, and also by increscent in thickness, energy absorption would be more.

Abstract: The ability of mortarless wall to restrain/sustain lateral load become important aspect to be consider in the design of wall. Therefore, this paper presents analyses of mortarless wall subjected to in-plane combined loading using finite element programs. The developed 2D finite element program is used in this research. The finite element models are developed based on micro modelling approach where each constituent of masonry (block and dry joint) connected each other by joints at their actual position. Eight nodded isoparametric plane element and six nodded zero thickness isoparametric interface element are used to represent block unit and dry joint respectively. The developed models are analysed under nonlinear environment. The most relevant results concern the strength response of the dry joint masonry walls subjected to in-plane combined compressive and shear loading. The results of finite element analysis compared with corresponding experimental results and its show good agreement. Parametric study also performed to consider the important parameters that effect the design of wall under combined loading. Significant features of the structural behaviour, ultimate capacity and observed failure mechanisms are addressed and discussed.