Investigation and evaluation of damages to surrounding structures and also estimation of rupture levels by considering the amount of deformations and the amount of adjacent gates are important issues in the nailing system in urban areas. In this research, we tried to evaluate the axial force of the nails and the deformation in concave and convex dams; in sandy and clay soils. In...
Housing is one of the major needs. The use of new and new technologies to increase the speed of construction, improve quality, increase earthquake resistance, increase the useful life of buildings is more than ever before. In this paper, four building methods Including LSF, LCF, 3D-PANEL and PRCS, 12 criteria for timely delivery of credit, ease of implementation, need for expert...
The construction of segmental precast concrete bridges is an increase due to its superior performance and economic advantages. This type of bridge is appropriate for spans within 50 to 250 m, known as mega-projects and the design optimization would lead to considerable economic benefits. In this study, a box-girder cross section of bridge superstructure with balanced cantilever...
In this paper, a modal pushover method is introduced for the assessment of the asymmetric-plan buildings in which, a load pattern is derived based on the story shears and story torque of building due to the simultaneous excitation in x and y directions. The proposed method is a single-run procedure and its significant advantage is its capability in consideration of the structural...
Vertically-mixed structures are buildings constructed with different materials progressing in the vertical direction. These buildings feature a concrete frame on the lower stories but a steel one on top. Reinforced Concrete (RC) column connected to steel column in story that called transition story. The sudden change of stiffness in the transition story in these structures and...
Since, generally, in high population areas and large cities for maximum use of land, buildings are constructed without distances or with insufficient distance, thus, during severe earthquakes, due to unbalanced vibration of the structure Adjacent bodies (which do not have enough distance from one another) and without considering the effects of the soil, the impact phenomenon...
In this research the simultaneously effects of foundation uplift and nolinear behavior of soil were investigated. Previous studies have showed that the effects of soil-structure interaction on seismic performance can be described through introducing a limited number of nondimensional parameters. In most studies it was assumed that the foundation is bonded to the soil and the...
The goal of this research is to identify and evaluate the factors of design excellence based on building information modeling (BIM) compared to the traditional method in relief structures including fire station centers and hospitals with an emphasis on crisis reduction. For this purpose, by studying the previous studies, simulation and modeling of the case study of firefighting...
Composite steel plate shear wall is usually made up of a steel plate and also a reinforced concrete cover, which is attached to one side or both sides of the plate by means of a shearing device. In innovative composite steel plate shear wall system, a gap is created between concrete cover and boundary beams and columns. The presence of this gap in small earthquakes does not cause...
Despite conservative requirements of existing building code regarding clear seismic gap distance of base-isolated (BI) structures to surrounding moat walls, seismic performance of these structures is still ambiguous under severe earthquake ground motions that may push the base slab of the isolation system to collide to the surrounding moat walls. Moreover, the temptation of...
High-performance reinforcement concrete due to its ductility and higher energy absorption has many applications in the field of passive defence than the normal concrete. These high-performance materials can be used in many cases, such as seismic improvement of building members. In some cases the structural capacity is increased, which is called strengthening. Strengthening can be...
One of the most important deficiency of buckling restrained braced frames is the concentration of lateral drifts in some specific stories and the soft story mechanism, under moderate to severe earthquakes. In this paper, in order to prevent the development of soft story mechanism in buckling restrained braced frames, asymmetric configuration along with a zipper strut is proposed...
Currently, to obtain the dynamic properties of structures in structural engineering, experimental relationships, mathematical models and computer software aids are mainly used. These dynamic properties depend on many details about material behavior and the compound of the structures, which could not all be taken into account in analytical models. Therefore, there are always...
Abstract:The use of fibers in concrete in order to improve concrete properties and mechanical behavior has started four decades ago and is growing. Fibers in concrete reduce the brittleness and provids ductile behavior of concrete. Fiber may be of plant species, artificial and metral which can improve mechanical properties of concrete under compressive load, tensile, flexural...
Magnetic water changes the electron configuration of the ions, followed by significant changes in hardness, electrical conductivity of surface tension and other physical and chemical properties of water. These changes in the cement reaction create a situation that has a significant impact on the improvement of the properties of concrete in fresh and hardened states and is...
Understanding the behavior of steel structures under fire loading is very important because many recent events indicate the vulnerability of steel structures to such a hazard. Extensive numerical and experimental studies have been conducted to investigate the behavior of different types of structural steel elements individually, steel structure connection, and steel moment frames...
The public sector has always sought to attract the private sector to partnership in the construction of infrastructure projects. The process of partnering in developed countries have less problems, while in developing countries, it faces with more serious barriers and problems. In these countries, including Iran, in spite of the proper initial reception, numerous complexities and...
The use of self-compacting high performance composites due to its unique properties has attracted the attention of researchers.The high compressive strength and tensile strength, high flexural strength, have attracted the attention of researchers to this type of cement composites.In this research, in the form of a comprehensive experimental work, using six basic mixing designs...
In this paper, a new kind of ring damper composed of three rings is introduced and investigated numerically and experimentally. The proposed damper combined three steel ring damper in order to dissipate energy of two different level of predefined excitation such as moderate and severe one. first fuse (outer pipe) and second fuse (inner pipes) can absorb energy in moderate and...
One of the latest innovations in nano-technology is the use of Micro-Nano Air Bubbles (MINAB) as a substitute for water in concrete. Using MINAB as a substitute for water used in concrete can be used to improve the properties of concrete. The use of super- Plasticizer can have an effective role in reducing negative effects MINAB on concrete properties. In this study, to...
Masonry infilled reinforced concrete frame buildings built prior to the introduction of modern seismic provisions have been observed to undergo damage in and around the masonry infill walls during most recent moderate to severe earthquakes. Considering interaction between masonary infill and frame is one of the challenges in the field of engineering research. Observation of past...
Since the batching, transportation, pouring, compaction and curing of the specimens used in laboratory testing of concrete, either from these employed in real structures, the in-situ methods are needed for assessing the quality of existing concrete in structures. Among the tests with partial failure, the "twist-off" method is used for determining the strength of concrete both in...
One of the important issues after an earthquake occurrence is to transfer residents to temporary accommodations. These points are areas of the city that have a higher safety factor against earthquake reoccurrence and have good access to management and relief centers. Due to the critical condition in the area after the earthquake, with the transfer of the township to these areas...
The need to use non-uniform members in the structures from the past till now had been proposed although the subjects and research references in this case are insufficient. Therefore the use of non-uniform members is inevitable and should be carefully examined. About this members the main subject that should be investigated is buckling that if it occures it leads to member failure...
Reinforced concrete is the most commonly used construction material. The durability of reinforced concrete mostly depends on the surrounding environmental and exposure conditions such as carbonation, corrosion, and freezing and thawing. Corrosion of steel in concrete is one of the major causes of premature deterioration of reinforced concrete structures, leading to structural...