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2 The viscoelastic damper has been successfully used in the wind and seismic design of super high-rise buildings abroad. Its control effect on the structural seismic wind response has been confirmed by waves, and its application in the country reduces the wind vibration Although there have been more studies on reaction in recent years, there are few practical applications. It is a passive control device. Its control effect is realized by the energy dissipation caused by the compression displacement and relaxation of the molecular chain network of the viscoelastic damping material. Install 0 inside a high-rise building, and use the structure to generate interlayer displacement in the vibration to drive the viscoelastic damping material to produce material shear deformation and dissipate energy, thereby reducing the response on the main load-bearing structural system. Because of its simple device and material economy, it has a wide application prospect in practical engineering.
1 The element complex stiffness matrix of the viscoelastic support rod is mainly in the form of support. 1 Kwong is structurally astonishing, and the herringbone clock is oblique in the form of a collapse, which is used afterwards. Various types of pavilion 2, the sticky sticks are made of two steel rods, the middle of the ship is made of sticks, sticky, and the liver is controlled by three children. The toe nipple is made of steel plates sandwiched between two viscoelastic phases. This can be simplified 1 Cast for the mechanics of Pavilion 4.
Fund Project Construction Ministry of Science and Technology Fund Project 990313, the author's profile Ge 63. Jiangsu Banzhou people. For 0, according to Hooke's law, there is shear strain, relative displacement between structural layers is the angle between the viscoelastic support and the floor, is the shear area of ​​the damping layer, and is the thickness of the damping layer, so the viscoelastic damping There are many mechanical models where the shear stiffness center of the material is a viscoelastic damping material. At present, the most widely used in structural vibration is the complex stiffness model.
It thinks that the damping force of the material is proportional to the elastic force, and the phase advances. The shear modulus of the material can be in the complex plane. 6 is the real shear modulus of the viscoelastic material, which is the imaginary part of the shear modulus of the viscoelastic material. , Is the loss factor of the viscoelastic damping material, which is the ratio of the damping force of the material to the elastic force. It reflects the energy consumption capacity of village materials.
Therefore, the complex shear stiffness of the village material is also due to the fact that the tensile stiffness of the steel rod is wider than that of the sticking layer, so the deformation produced by it can be ignored, and the deformation produced by the burial device can be ignored. , Therefore, because the element node displacement column vector in local coordinates and the element node displacement column vector in global coordinates satisfy the relationship, which is the square of the local coordinate 1 axis and the overall coordinate wide 2 axis. Because the element node force column vector in global coordinates is The element node force column vector in the local coordinates satisfies the relational partial r. Therefore, the relationship between the element node force column vector and the element node displacement column vector in the overall coordinate system of the viscoelastic support rod in the global coordinate system can be obtained from equation 57. The complex complex stiffness matrix of the unit can be assembled. The overall complex stiffness matrix of the viscoelastic support bar is 2 the equivalent damping ratio of the structure. According to the above derivation, from the overall structure, the motion equation of the steel structure high-rise building is MXliTAHA array The magic is the total lateral stiffness matrix of the structure, whose center is the lateral stiffness matrix of the original structure, and the artificial stray matrix will contribute to the lateral stiffness matrix of the structure.
Qiaorenxin 1 owes. , Is the effective damping loss of the whole structure after setting 0 support, and the damping loss factor of the original main steel structure, and 1 is the damping loss factor of the 0 support system used. The household is a pulsating wind load vector along the wind.
Therefore, it is set that the motion equation of the steel structure high-rise building of 0 is actually the equation (3) with the addition method of â‘´. For mode frequency, 1 N loss factor.
Obviously, comparing Equation 12 and Equation 13 can be derived that this is the calculation formula for setting the effective damping loss factor of the 0 mode high-rise building. According to the equivalent relationship between the energy dissipation around the vibration of the single-degree-of-freedom vibration system of the complex damping theory and the viscous damping theory, the vibration mode damping ratio of the structure in the viscous damping theory and the damping loss factor in the complex damping theory can be easily guided The relationship between.
The damping ratio of the 7th vibration mode.
Substitute equation 15 into equation 14. The guide is set, 0 steel structure is high to be effective for building vibration; Nibi ’s formula 3 damper parameter design The damper parameter must be selected reasonably to talk about the need for bipedal shock absorption. Two methods. For general high-rise steel structure buildings, the following calculation method is used to try to input the damping ratio of the overall structure, and the seismic response of the structure is calculated. If the code does not meet the requirements of the code, the damping ratio is re-entered until the structural response meets the requirements of the code. The damping ratio of the overall structure can be used as the basis for the design of the damper parameters. The specific method is to set the parameters of the group damper. Obtain the structural damping ratio according to formulas 2489 and 16; if the resistance does not reach the design requirements, the ratio. That is, the old and the new are sold in one. 1 To achieve the myonibi that makes the structural response meet the requirements of the specification or according to the above public, for high-rise steel structure buildings that are similar to the shear type, another simple method can be used to consider the situation in which dampers are arranged on each floor in general. Units The formulas of shear energy dissipation and maximum elastic energy of the viscoelastic material in the vibration cycle are: the energy dissipation ratio of the whole structure supported by the original dissipation structure and viscoelasticity can be dissipated respectively, is the total deformation energy of the original structure. The total energy consumption of the structure, especially the layer shear stiffness of the structure, is the volume of the damping layer. ; It is the number of buildings.
The thickness of the damping layer is determined according to the criterion that the shear strain of the damping layer should be less than 1, that is, it should be greater than the relative displacement of the two sides of the factory on the damping layer, 80, where 1 takes the maximum relative displacement between structural layers.
4 Calculation example analysis In this example, the seismic response time-history analysis was carried out on a steel frame structure with a total height of 37.5 mm, 12 floors, 33 spans and 41 spans. For the outer material, each layer has two swift elastic elastic palms and inner objects; each layer has Kwong Road, the factory of Liang Du is fixed and calculated according to the beam unit. 5 materials are 16 rivers! 1 steel, the plate is made of toothed steel plate and concrete superimposed, according to the equivalent quality conversion cost example according to the design of 7-degree fortification earthquake, so the maximum amplitude of seismic wave is 358, considering the situation of remote earthquakes, class 1 site soil, characteristics The period is 0.558, so the seismic acceleration record with an earthquake duration of 88 is used. Since 1 is 1550, the limit is 68.2. According to the compiled program, the structural damping ratio of this steel frame building is calculated from 0.
02 caught high. 21; Take a certain point on the top of the dead body as an example, such as the displacement time-history curve before and after the viscoelastic support of the structure is installed, such as the 5 conclusion element complex stiffness matrix, the equivalent damping ratio of the structure is calculated, and on this basis, the damper parameters are calculated. For design, a design method suitable for general steel structures and a simple method suitable for shear steel structures are proposed. Then take the 12-story high-rise steel structure as an example to verify the good effect of the muscle device on the seismic response control of the high-rise steel structure.
1 Dade; Festival. Damping vibration and noise reduction technology 1. Xi'an Jiaotong University Press. 1986 3 Qu Weilian. Practical design method of viscoelastic damper for wind vibration control of steel high-rise buildings, Proceedings of the 1st National Conference on Wind Effects, Wuhan Huazhong University of Technology Press, 1997, 6578
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