Mohsen Malekinejad

Islamic Azad University, Sirjan Branch, Iran · Civil ENgineering

The performance of cement-based materials depends on the characteristics of solid particles at the nano-scale or nanometer porosities in the interfacial transition zone between cement particles and aggregate. Heat significantly affects the properties of these particles and the connection between them. Accordingly, the present study seeks to investi...

In this paper, a simple mathematical method, based on a continuous approach, is proposed to determine the natural frequencies and mode shapes of trussed-tube systems in tall buildings. Braces are modelled as transverse springs at specific locations along with the height of the structure. Framed-tube system is idealized as a cantilever beam, represe...

In this paper, a method is proposed to provide a simple model of buckling restrained braces. After introducing the elements, taking into account all parts of buckling restrained braces, a sample of this type of braces is modeled in finite element Abaqus software. After confirming the numerical model using the available laboratory results, which is...

In this paper, the continuum model, which is known as Kwan model, has been presented for the analysis of tall buildings that have been as an appropriate approximation of the overall behavior of the structure. Tall building was modeled as a cantilever beam and analyzed with the assumption of flexural behavior based on Euler–Bernoulli Beam Theory, th...

In this paper, a method is proposed to provide a simple model of buckling restrained braces. After introducing the elements, taking into account all parts of buckling restrained braces, a sample of this type of braces is modeled in finite element Abaqus software. After confirming the numerical model using the available laboratory results, which is...

This paper presents a numerical investigation of buckling restrained brace (BRB) frames (BRBF) and a comparison with concentrically braced frames (CBF). A simplified core-spring finite element model was used to model BRB elements. Four types of CBF (X, V, inverted V, and two-story X) and four types of BRBF (diagonal, V, inverted V, and two-story X)...

The use of bracing systems is one of the most suitable methods to control the lateral displacement of a structure as well as to improve the seismic rehabilitation of moment frames. The bracing systems used in the design of new systems and the rehabilitation of weak old structures are buckling restrained braces. In this study, the effect of this on...

In this paper, a continuous–discrete approach based on the concept of lumped mass and equivalent continuous approach is proposed for free vibration analysis of combined system of framed tube, shear core and outrigger-belt truss in high-rise buildings. This system is treated as a continuous system (i.e., discrete beams and columns are replaced with...

In this article, dynamic parameters (natural frequencies and mode shapes) of tall buildings that consist of framed tube and shear walls are obtained using a simple approximate method. The three-dimensional structure is replaced by an equivalent cantilever beam, considering both bending and shear deformations. On the basis of dynamic equilibrium, th...

SUMMARY In this study, effects of applying higher order axial displacement distribution to solve a continuum model for static analysis of the combined system of framed tube, shear core and outrigger–belt truss system in high-rise buildings are investigated. Framed tube system is modeled using an orthotropic box beam analogy approach and the interac...

In this paper, on the basis of the D'Alembert's principle, approximate formulas for dynamic response of tubular tall building structures are presented. Using D'Alembert's principle and applying the compatibility conditions on deformation of the tubes, the governing dynamic equation of the tubular structure's motion is derived. Then, natural boundar...

SUMMARY This paper deals with a new and simple mathematical model that may be used to determine natural frequencies and mode shapes of a multistory building that consists of a framed tube, a shear core and multi-outrigger–belt trusses. The effect of outrigger–belt truss and shear core on a framed tube was modeled as a concentrated moment placed at...

A simple, yet accurate analytical approach based on energy principles is developed for quick computation of natural frequencies and mode shapes of multistory buildings constructed using framed tube, shear core and double belt trusses systems. The approach here is based on development of a continuum model that would be equivalent, in major motions,...

In this paper, an efficient technique is presented for static analysis of tall buildings with combined tube-in-tube and outrigger-belt truss system while considering shear lag effects. In the process of replacing the discrete structure with an elastically equivalent continuous one, the structure is modeled as two parallel cantilevered flexural-shea...

In this paper the dynamic response of tube-in-tube systems for tall building structures is investigated. Inner and outer tubes are modeled using equivalent continuous orthotropic membranes; in which, each tube is individually modeled by a cantilever box beam. By applying the compatibility conditions on deformation of the two tubes, the governing dy...

In this article, an approximate method of determining the vibrational frequencies of coupled shear walls with inclusion of axial force effects is presented. For this purpose, first the continuum approach is adopted for modelling linked beams. Then by applying force equilibrium conditions to each of the walls, and enforcement of displacement compati...

In this paper a simple mathematical model for approximate static analysis of combined system of framed tube, shear core and two outrigger-belt truss structures subjected to lateral loads is presented. In the proposed methodology, framed tube is modeled as a cantilevered beam with a box section and interaction between shear core and outrigger-belt t...

In this paper a simple mathematical model is presented for estimating the natural frequencies and corresponding mode shapes of a tall building with outrigger-belt truss system. For this purposes an equivalent continuum system is analyzed in which a tall building structure is replaced by an idealized cantilever continuum beam representing the struct...

In this paper, a complement to the Hoek-Brown criterion is proposed in order to derive the strength of anisotropic rock from strength of the corresponding truly intact rock. The complement is a decay function, which unlike other modifications or suggestions made in the past, is multiplied to the function of the original Hoek-Brown failure criterion...

In this paper, Soil-Structure Interaction (SSI) effect is investigated using a new and integrated approach. Faster solution of time dependant differential equation of motion is achieved using numerical representation of wavelet theory while dynamic Infinite Elements (IFE) concept is utilized to effectively model the unbounded soil domain. Combinati...

Most of steel structures in various industries are subjected to corrosion due to environmental exposure. Corrosion damage is a serious problem for these structures which may reduce their carrying capacity. These aging structures require maintenance and in many cases, replacement. The goal of this research is to consider the effects of corrosion by...