Self-compacting concrete is a special concrete that flows with its weight in the form and does not need to shake. based on experimental findings, its compressive strength decreases with an increase in the specimen size; this phenomenon is called “size effect and its beginning is a nonlinear failure in concrete and other fragile materials. The purpose of this study was to...
By reviewing the literature on steel slit yield dampers (SSD), this study investigated and compared the effect of new strip shapes and geometric patterns on the behavior of this type of dampers. This study investigated a reference slit-less sample (solid) along with nine samples with a single row of blades or slits and three different shapes and geometric patterns, namely simple...
In this paper, the influence of Winkler type elastic foundation on the free vibration behavior of non-local Euler-Bernoulli beam with varying cross-section is semi-analytically investigated. For this purpose, the governing equation of motion is derived based on nonlocal elasticity Eringen’s model and Hamilton’s principle. The power series approximation is applied to solve the...
Past studies have shown that aftershocks can increase structural damage, especially for structures damaged in the mainshock and experienced nonlinear behavior. This damage is generally the result of increased lateral displacement of the structure and thus, it is necessary to estimate the lateral displacement of the structure under seismic evaluation accurately. Although the...
Discrete singular convolution is a new numerical method that its ability to vibrational analysis has been demonstrated in the last decade. A lot of research on how to apply the complex boundary conditions of the different issues using this method is carried out and a variety of solutions have been proposed in this regard. Applying the boundary conditions in the governing...
There are a number of reasons for considering web openings in steel structures with I-sections. Design of these structural members is always a practical challenge in steel construction. There are several design methods available in the literature for design of these components. Most of these methods rely on the moment-shear-axial interaction curves. However, the preliminary...
Geometric nonlinear analyses are used in many structural problems, such as the determination of failure load, as well as the study of buckling mechanism. Nevertheless, due to the complex nature of this type of problems and the absence of a comprehensive analytical solution for them, numerical methods are utilized in practice to approximate the exact response of these systems. In...
According to the Eurocode, the partial safety factor (γM) is a coefficient related to the material properties considering the uncertainties in geometry and modeling, which design value for the material properties are determined by dividing the actual value of the material properties by this coefficient. In this paper, determination of γM considering uncertainties for the Persian...
Damage occurrence is always inevitable in structures. So far, many examples of damage types in engineering structures have been recorded with many losses of human and financial. For this reason, the detecting of structural damages during its exploitation to provide safety with the lowest cost has been the subject of many researchers in the last two decades. In this regard, the...
There are numerous old arch bridges in Iran that have been used as railway bridges for more than eighty years. In Iran's railway network, there are about 3,700 bridges which all of these have been designed based on service load in that time (low-speed trains) and are still serving for trains at maximum speed of 100 km/h. Using of high-speed trains has been spread all over the...
Bridges are one of the major infrastructures of a country, which, in the event of severe seismic activity and the occurrence of collapse, can cause severe damage in different regions and create a severe crisis. Bridges with very long spans have always been a great challenge for engineers throughout history. Cable-stayed types of bridges are becoming more and more popular in the...
The high depth created favorable space for placing the openings which are to provide some capabilities such as mechanical and electrical installations, but these openings reduced load bearing capacity of the beams. One solution to the mentioned shortcoming is to use FRP-Composite sheets; the effect of FRP-Composites in improving load bearing and ductility of concrete members such...
Seismic sequence as a result of occurrence of strong and moderate earthquake ground motion in a short time strongly affects the seismic response of structures. This kind of excitation causes, in many cases, more deteriorated effects compared to the corresponding single ground motion. The aim of this paper is to investigate the effect of seismic sequence of earthquake ground...
One of the most important manifestations of sustainable development in any country is the country's productivity of sustainable sources of income. In fact, sustainable income is the basis for sustainable urban development. In the current century municipal financing is one of the most important issues in urban management, and in our country there has always been a discussion and a...
Nowadays, one of the newest studies in the field of structure engineering and earthquake is the acquisition of systems that will quickly return to pre-earthquake and service after an earthquake. Thin steel plate shear walls in reinforced concrete frame with replaceable as a sacrificial member or fuse will protect the sidewall system during an earthquake. In this paper, a method...
By increasing the height and slenderness of tall buildings, the wind-induced dynamic response especially crosswind response becomes the governing parameter in the occupant comfort requirement of tall buildings. In the present study, crosswind response of tall buildings has been investigated using the frequency domain analysis of multi-degrees-of-freedom systems based on the...
Between various sectors of civil engineering, concrete is one of the most widely used materials in the building industry. The use of pozzolanic materials is one of the solutions for high strength concrete production. High-strength concretes have high compressive strength, high adhesion, very low w/c ratio and permeability and therefore high durability. In this study, zeolite and...
Economic tools are definitely an effective way to encourage or enforce contractors to enforce environmentally-friendly practices. Previous studies on this subject mainly focus on the management of waste of construction and demolish (C & D) from the static point of view, which does not take into account the nature of its dynamic by taking all necessary activities in the waste...
Concentric bracings (CB) are one of the most prevalent lateral load bearing systems in steel structures. These bracings have a remarkable lateral stiffness and strength, but their compressive buckling prevents them from being ductile and absorbing optimal energy. Consequently, in recent decades, researchers have conducted extensive studies to improve the concentric bracing...
Coupled steel plate shear wall consist of two shear wall with flat web plate with rigid beam-column connection, that connected with coupling beam at story level. Coupled steel plate shear wall consist of two panels with rigid beam-column connection, that connected with coupling beam at story level so its possible to use opening in wall. In this study, two types of six story steel...
In this research, the co-operation of steel and concrete in composite columns is considered. Using numerical modeling to study the behavior of these sections, a new type of composite sections named concrete-filled double-skin steel column is introduced. The factors affecting numerical simulation, which bring this simulation closer to the laboratory conditions, determine the axial...
Concentrically braced frames (CBFs) have become prevalent as a lateral load resisting system due to their rigidity, low lateral displacement and ease of implementation over the last three decades. These advantages encourage the increasing utilization of this system in the construction industry. Despite the advantages of CBFs, the lack of ductility and buckling of the bracing...
Recently, base isolation techniques are applied as a resisting system to protect the structures from seismic and dynamic loadings. Due to their importance, in this paper, an optimum arrangement of lead rubber bearing (LRB) and friction pendulum system (FPS) is investigated in irregular buildings and its performance is compared with a regular case. For this purpose, 3 types of...
One of the most interesting topics in the geotechnical and geophysical engineering is the use of surface waves to characterize the earth subsurface layers. In a vertically heterogeneous media, the phase velocity of the surface wave is a function of the frequency (the frequency-phase velocity relationship is called dispersion curve). The dispersion curve is calculated by the shear...
Structures are subjected to different kinds of loads during their lifetime, such as those caused by daily temperature swings, traffic loads, abrasion and severe loads like earthquake. The occurrence of damage in building structures, oil platforms, and generally all structural systems is inevitable. Different kinds of failure in various engineering structures have been observed so...