Reinforced concrete walls are commonly used as the primary lateral-force-resistingsystem for tall buildings. As the tools for conducting nonlinear response history analysis have improved and with the advent of performance-based seismic design, reinforced concrete walls and core walls are often employed as the only lateral-force-resisting-system. Proper modeling of the load versus deformation be...

The mechanical behavior of the mesostructure of concrete is simulated by a three-dimensional lattice connecting the centers of aggregate particles. The model can describe not only tensile cracking and continuous fracture but also the nonlinear uniaxial, biaxial, and triaxial response in compression, including the postpeak softening and strain localization. The particle centers representing the ...

the creep/recovery behavior of wood flour-polypropylene was compared with medium density fiberboard (mdf) and particleboard. for this purpose, wood flour-polypropylene composites (with and without compatibilizer)were manufactured by using a laboratory twin-screw extruder. the mdf and particleboard panels were obtained from local producers. short term flexural creep tests at 30% of ultimate bend...

The objective of the current study is to develop a simple formula to estimate the fundamental vibration period of tall buildings for using in equivalent lateral force analysis specified in building codes. The method based on Sturm-Liouville differential equation is presented here for estimating the fundamental period of natural vibration. The resulting equation, based on the continuum represent...

This paper attempt to predict the shear strength of high strength concrete beam with different shear span of depth ratio without web reinforcement. The large data base available has been clustered and a linear equation analysis has been performed . The prepared models are functions of compressive strength , percentage of flexural reinforcement and depth of beam. The proposed models have been va...

nowdays, production of high quality engine oils is one of the worries of our country’s engine oil industry. in this study, the behavior of four commercial polymers used in nation motor oil industry in obtaining the best viscosity index improver was investigated. in this regard, viscometric behavior, shear stability and polymers’ performance for engine cranking were compared at low temperature. ...

A Trigonometric Shear Deformation Theory (TSDT) for the analysis of isotropic plate, taking into account transverse shear deformation effect as well as transverse normal strain effect, is presented. The theory presented herein is built upon the classical plate theory. In this displacement-based, trigonometric shear deformation theory, the in-plane displacement field uses sinusoidal function in ...

Geopolymer concrete (GPC) is obtained by activating industrial wastes such as fly ash with chemical liquids sodium hydroxide (NaOH) and silicate (Na2 SiO3). In order to use environmentally friendly GPC from instead of portland cement (OPC), its behavior in structural elements important should be investigated detail. Load-displacement characteristics, flexural shear stiffnesses crack development...