CN-116305421-B - Method and system for solving parameters of transverse damping system of large-span bridge in mountain area

CN116305421BCN 116305421 BCN116305421 BCN 116305421BCN-116305421-B

Abstract

The invention relates to a method and a system for solving parameters of a transverse damping system of a large-span bridge in a mountain area, wherein the method comprises the steps of obtaining a bridge structure, establishing a space finite element model, obtaining target design displacement, setting initial damping parameters of dampers at all positions of the bridge, calculating actual displacement based on the damping parameters at the moment, obtaining an adjusted vector of the dampers according to the difference between the target design displacement and the actual displacement, calculating an adjustment vector by combining the adjusted vector and an influence matrix, calculating the adjusted damping parameters based on Shi Diaoxiang, judging whether the adjusted damping parameters meet design requirements, if so, taking the adjusted damping parameters as final damping parameters, otherwise, repeating the steps. Compared with the prior art, the method and the device have the advantages that through the basic principle of influencing the matrix, the multi-tower/pier coupling effect in the transverse damping system and the strong nonlinear behavior of damping measures are considered, and through the iterative calculation of rapid and stable convergence, the reasonable design parameters of the damping system at each tower/pier position can be determined.

Inventors

GUAN ZHONGGUO
ZHANG SHICHUN
LU JUNRUI
XIAO TAO
LI YANG
WANG SHAOXIAO
WU YONGMU
XIAO YIFENG

Assignees

同济大学
中国公路工程咨询集团有限公司

Dates

Publication Date: 20260512
Application Date: 20230215

Claims (7)

1. A method for solving parameters of a transverse damping system of a large-span bridge in a mountain area is characterized by comprising the following steps: Acquiring a bridge structure, establishing a space finite element model, acquiring target design displacement, and setting initial damping parameters of dampers at each position of the bridge; Calculating actual displacement through a space finite element model based on the damping parameter at the moment, obtaining the regulated vector of the damper according to the difference between the target design displacement and the actual displacement, calculating the regulated vector by combining the regulated vector and an influence matrix of the damping parameter at the moment, obtaining the adjusted damping parameter based on Shi Diaoxiang calculation, judging whether the adjusted damping parameter meets the design requirement, taking the adjusted damping parameter as a final damping parameter if the adjusted damping parameter meets the design requirement, otherwise, repeating the step; the influence matrix is Matrix of influence vectors { δ j } of dampers at each position: Wherein, the Setting the number of positions of the damper on the bridge, wherein the influence vector { delta j } is the change of the displacement of the damper at the m positions caused by the unit change of the damper parameter at the j-th position; Modulated vector { Is } is Damper target design displacement { at each location { With its actual displacement } Difference of }: Wherein, the =0、1、2、..., The device is used for representing the actual displacement corresponding to the initial damping parameters of the dampers at each position of the bridge and the actual displacement corresponding to the adjusted damping parameters; tone vector { Is } is Damping parameters of the damper at the respective positions are compared to the adjustment values of the initial damping parameters: Wherein, the In order to influence the matrix, Is the regulated vector.
2. The method for solving parameters of a transverse damping system of a large-span bridge in a mountain area according to claim 1, wherein the judging whether the adjusted damping parameters meet the design requirements is specifically as follows: Calculating the adjusted actual displacement through a space finite element model based on the adjusted damping parameters, calculating the relative error between the target design displacement and the adjusted actual displacement, and if the relative error is not greater than a preset threshold value, the adjusted damping parameters meet the design requirement.
3. The method for solving parameters of a transverse damping system of a large-span bridge in a mountain area according to claim 2, wherein the preset threshold value is 1%.
4. The method for solving parameters of a transverse damping system of a large-span bridge in a mountain area according to claim 1, wherein the adjusted damping parameters are as follows: Wherein, the The damping parameter is used for representing the initial damping parameters and the adjusted damping parameters of the dampers at all positions of the bridge.
5. The method for solving parameters of a transverse damping system of a large-span bridge in a mountain area according to claim 1, wherein the damping parameters of the dampers are yield force, and the initial damping parameters of the dampers at each position of the bridge are set specifically as follows: the initial yield force { Q 0 } of each damper was set to 10% { V }, where { V } is the seismic shear vector at each tower/pier location of the laterally fixed system.
6. The method for solving parameters of a transverse damping system of a large-span bridge in a mountain area according to claim 5, wherein when solving an influence matrix, the tangent flexibility is replaced by the tangent flexibility within a certain range of amplitude (Q n ,Q n +DeltaQ) at corresponding yield force, so as to obtain a relatively stable influence matrix, wherein DeltaQ is 3% { V }.
7. A mountain area large-span bridge transverse shock absorption system parameter solving system, characterized in that the mountain area large-span bridge transverse shock absorption system parameter solving method based on any one of claims 1-6 comprises the following steps: The initialization module is used for acquiring a bridge structure, establishing a space finite element model, acquiring target design displacement and setting initial damping parameters of dampers at each position of the bridge; The solving module calculates actual displacement through a space finite element model based on the damping parameter at the moment, obtains the regulated vector of the damper according to the difference value between the target design displacement and the actual displacement, calculates the regulated vector by combining the regulated vector and the influence matrix of the damping parameter at the moment, calculates the regulated vector based on Shi Diaoxiang to obtain the regulated damping parameter, judges whether the regulated damping parameter meets the design requirement, takes the regulated damping parameter as the final damping parameter if the regulated damping parameter meets the design requirement, and otherwise, repeats the step.

Description

Method and system for solving parameters of transverse damping system of large-span bridge in mountain area Technical Field The invention relates to the technical field of damping of bridge engineering structures, in particular to a high-efficiency solving method and a high-efficiency solving system for determining design parameters of a damping system at each tower/pier position on a large-span bridge in a mountain area. Background A new round of bridge construction peaks is currently formed. Because of mountainous and hilly terrains, a plurality of deep valleys are flushed, and the requirements for large-span bridges with single span of 100 m-400 m are very high, common bridges comprise large-span continuous beam bridges, arch bridges, single-tower cable-stayed bridges and the like. However, the strong earthquake frequently occurs, the risk of earthquake disasters is huge, and the design and construction of the bridges are provided with serious challenges. Compared with a middle-small span bridge, the large-span bridge has higher beam height and higher upper structure mass, and the inertial force response under the action of an earthquake is larger, more importantly, due to the influence of mountains, hills and valley terrains, the lower structure pier heights of the large-span bridges often differ greatly, and the lateral rigidity of the bridge piers is inversely proportional to the third power of the height of the bridge piers, so that the lateral constraint rigidity at each tower/pier position often has the difference in order of magnitude, and the difference leads to the extremely irregular distribution of the lateral rigidity of the whole structure, so that the response state of the structure under the action of the earthquake power is very unfavorable. Extensive research has shown that in high intensity seismic areas, it is neither economical nor feasible to attempt to combat seismic effects by increasing pier stud size and reinforcement, and appropriate seismic reduction and isolation measures need to be introduced to create a seismic reduction and isolation mechanism. However, unlike the case where the main beam seismic response at each tower/pier is substantially identical under the action of a longitudinal earthquake, the main beam seismic response at each tower/pier may have different amplitude values and frequency characteristics, particularly, the bridge having different heights at each tower/pier in a mountain area, so that the response of the seismic reduction and isolation measures is also greatly different, and therefore, a reasonable seismic reduction and isolation system should select different design parameters at each tower/pier to adapt to and balance the influence caused by the difference of the heights of the towers. Under the normal operation load, the main beams at each tower/pier position need to be transversely restrained, so that the transverse shock absorption measures of the bridge often adopt displacement dependent dampers. Niu et al propose a design method with displacement response as a design control target aiming at a shock absorption system of a cable-stayed bridge transversely adopting a steel damper. Camara and the like determine the maximum damping force of the viscous damper and the yield force of the steel damper through the concrete cracking critical force at the bottom of the main tower of the cable-stayed bridge, and an approximate design method based on equivalent single degree of freedom is provided, however, for bridges with large difference in pier heights in mountain areas, the earthquake response cannot be equivalent to single degree of freedom. Wen et al explore a reasonable damper parameter setting range of a large-span cable-stayed bridge triangular steel damper transverse damping system based on a member damage probability analysis method. In practical large-span bridge engineering, such as an Lanzhou Xiguan yellow river bridge, a Yongning yellow river bridge, a Ningbo spring dawn bridge, a Yinchuan river Huang Heda bridge, a camphor tree Ganjiang R two bridge, an Lanzhou Chaixia yellow river bridge, an Shanghai Kun Yang Luyue river bridge, an Guangxi Abrus bridge and the like, approximate optimal values of damping parameters are calculated through a preset multi-working-condition parameter sensitivity analysis method. Shen et al further calculated reasonable design parameters of the damper by utilizing a full exhaustion method in combination with numerical software programming aiming at the triangular steel plate damper damping and energy consumption device. It should be noted that, due to the influence of the transverse flexibility of the main beam, the seismic response at each tower/pier position in the bridge transverse anti-seismic system has a remarkable coupling effect, that is, the design parameters of the shock absorption measures at each tower/pier position are not mutually independent variables, and the strong nonlinear behavior of the shoc