steel pipe structure tower wind load earthquake

steel pipe structure tower wind load earthquake Author: first papers network update time :2012-8-30 16:16:02 Abstract: The characteristics of ethylene steel pipe structure tower. In civil engineering design, computing and disaster disaster planning, the impact of the largest and most prone to engineering structures fail even undermine the role of wind loads and seismic. Practical engineering study, the use of existing large-scale finite element software welded pipe structure tower model, on the model of the dynamic characteristics of wind loads and seismic response analysis, which is designed to provide reliable computing and analytical basis. Keywords: steel pipe structure tower; modal analysis; wind loads; earthquake The petrochemical installations ethylene steel pipe structure tower due to its technological characteristics of the general height of about 100m, high altitude, high steel requirements, large steel high cost. In civil engineering design, computing and disaster disaster planning, wind loads, earthquake and snow loads, floor loads should be considered a major interference and role. One of the most influential and most likely to lead to engineering structural failure or even destruction of the devaluation of the wind loads and seismic loads. For high, large, thin, long flexible structure, wind loads is important or even decisive design load, improper handling can cause structural damage and destruction brought significant losses to people's lives and property. A high-rise building has structural characteristics of the low-rise buildings (1) The horizontal load to be the deciding factor. Control the load of the structural design of low-rise housing is generally based on the gravity represented by the vertical load, the load of high-rise buildings in the mainly horizontal load of wind loads and seismic effects, they become a decisive factor in structural design. The structure height increases, the impact of a sharp increase in horizontal load. (2) Structure sideshift main control objectives. In the analysis of low-rise housing structure, usually only consider bending deformation, deformation control for vertical displacement. The structure of high-rise buildings sway control both important, ensure the safety of the structure, and the second is to ensure the structural requirements for normal use and comfort. Drift Control become a guarantee of reasonable comprehensive index structure. (3) structural dynamic response become a key factor. The key factor in the design of low-rise housing mainly static processing, and high-rise buildings, wind-induced vibration, seismic dynamic response of the design considerations, the structure of the dynamic characteristics of the formation of structure is very important load effect. As the complexity of the role of wind and earthquake, high-rise buildings against wind and earthquake response analysis is still in the in-depth study. Dynamic response of high-rise buildings by the structural characteristics of the environment and the role of various factors combined effects of the decision, is a manifestation of the structure of the overall performance, but also shows that to get the structural dynamic response characteristics, must be integrated into the structure of the system, this is a high-level structure of power to analysis and design difficulty another reason. (4) reduce the weight of great significance. Structural design requirements of high-rise buildings as much as possible the use of lightweight, high strength and good performance materials, on the one hand, to reduce the gravity load on the basis of pressure and cost can be reduced; directly related to the quality of the other hand, due to the structure suffered power load size, less small mass can help reduce the structural dynamic loads. (5) The structural system is reasonable or not depends on the effective ability to provide lateral resistance. Meet architectural styling and space design premise, the structure of the system and the structure of the program mainly by how effectively form a sufficient lateral force resisting system. The structural system of the economy mainly depends on the validity of the lateral force resisting system. For this reason, high-rise building height different structural system. Reasonably determine the lateral force resisting structural system become the key to the structural design of high-rise buildings. Second, spiral pipe structure tower of wind resistance studies. The carbon steel pipe for wind load is one of the main load of the building, although the magnitude of its role is smaller than the average seismic loading, but its role in frequency is higher than the seismic loading is much higher. With the increase in height of the structure, wind load calculation and analysis of the role is becoming increasingly important. In the past two decades, domestic and construction of a large number of high-rise buildings and large span structure. High-rise building structure wind loads and wind vibration response calculation and analysis is very important, it is the basis for structural design. Structural damage caused by the hurricane are not infrequent, especially to strengthen the structure of the defense capabilities of the high-rise building structure of the hurricane, reasonable structure wind resistant design is extremely important. Regardless of the type of wind, the role of wind on buildings just near the surface wind flow near the wind near the ground, through the region of different terrain and landscape, plus the wind itself changes, so that in a different space and time, the wind the current speed and direction are different from the near-Earth Wind apparent randomness and disorder on the role of the building. A large number of measured records and test results showed that: nearly to the wind is divided into two parts, part of the mean wind, and its structural role, is the static nature of; another portion is a fluctuating wind, its structure wherein the average power wind change cycle is much larger than the structural natural periods, the role of the structure can be regarded as static wind component; fluctuating wind cycle range may be close to the structural natural periods, the role of wind structure can not be reduced to a static The force must be considered the dynamic role. To this end, the architectural structure of wind-induced effects include static effects and dynamic effects. Static wind effect is caused by static wind loads on the structure of the static internal force and static displacement; dynamic wind effects caused by fluctuating wind load, and whirlpool interference force structure vibration response, including vibration internal force, vibration, displacement and vibration acceleration. Fluctuating wind load on the structure of the dynamic characteristics of the dynamic response of structures structure. Wind-induced vibration of the structure when the very rigid structures, caused by the fluctuating wind force of inertia is not obvious. Softer structures, in addition to static wind load should be included in the size of wind-induced vibration inertial force. The structure static wind mechanism is relatively simple. The structure of dynamic wind mechanism is very complex, including wind-induced vibration and self-excited vibration in two parts. Wind-induced vibration of the structure is mainly caused by fluctuating wind buffeting wake, vortex shedding and turbulence caused by the wind to the across-wind and torsional vibrations. Particular, the structure of the self-excited vibration due to the movement of the structure so that the wind speed change with respect to the building, resulting in the structure of the vibration velocity of the wind speed with changes, such as the movement of the building and the generated additional dynamic load-called air The aerodynamic damping, the aerodynamic action changed the structure of the damping force during vibration. When the structure is subjected to the total damping force is negative, the structure of the wind contained self-excited vibration will tend divergence, i.e. amplitude increasing, eventually leading to the destruction of the structure. The high-rise, high-rise, long span suspension bridge, and tower structure, relatively small stiffness vibration cycle length, in most cases they suffered wind load is also more important than the seismic loading. , Steel pipe structure tower seismic research 1990s, the seismic performance of the steel pipe is rarely suspected, but the Northridge earthquake (Northbrides) January 17, 1994 and January 17, 1995 Japan's Hanshin (Kobe) earthquake, a large number of steel pipe The structural framework of brittle fracture, this phenomenon has aroused widespread concern of the engineering sector and academia. China is located in the circum-Pacific seismic belt and the Mediterranean, a Himalayan earthquake belt frequent seismic activity. With the increasingly widespread application of various types of steel pipe structure to carry out the significance of the study of the seismic performance of steel pipe. Japan's Kobe earthquake and the Northridge earthquake caused serious damage to many steel frame, and The 2 States after the earthquake a lot of research to figure out the failure causes and improvement measures are proposed. The survey found that the main failure mode of the steel pipe structure node destruction column destruction column foot connection destruction. Northridge and Hanshin earthquake, earthquake damage is to promote the rapid development of the carbon steel pipe structure in all respects. After the Northridge earthquake, the U.S. Federal Emergency Management Agency initiated a project of up to four years, the examination of the research and development of steel frame structure, evaluate, repair, reinforcement and construction of the construction aspects of economic and effective measures; Japan, European countries have also committed to investigate the structural mechanism of brittle fracture in the development of a new structure type, and the reinforcement of the existing node type and performance like this steel pipe URL is:http://www.netgms.com/spiral-pipe.html