Modification method of finite element model of steel bridge based on monitoring value of non-uniform temperature response

Abstract

The invention discloses a steel bridge finite element model correction method based on a non-uniform temperature response monitoring value. The method mainly includes the steps of: 1) analyzing the year-round monitoring data of a steel bridge, and finding out the response rule of structure under the action of a non-uniform temperature field, 2) establishing an initial finite element model according to design data, 3) preliminarily determining the horizontal stiffness of a steel bridge bearing by iteration method, 4) performing sensitivity analysis on the steel bridge on the basis of steel bridge temperature response data, and determining a design variable having a high correlation coefficient with actually measured data, and 5) conducting optimization analysis on the steel bridge finite element model by reducing the difference between a finite element calculation result and the actually measured data. Compared with the universally adopted finite element model correction method based on experimental modal data and other dynamic response results, the method provided by the invention has the advantages of simplicity and accuracy, low cost and good safety.

Description

technical field [0001] The invention belongs to the field of civil engineering numerical simulation analysis, and relates to a method for correcting a finite element model of a steel bridge based on non-uniform temperature response monitoring values. Background technique [0002] With the rapid development of the national economy, the construction of large bridges in our country is speeding up. Steel bridges are widely used in bridges due to their strong spanning ability and fast construction speed, and play a key role in the local environment, economy and social life. Steel bridges have large spans, various types of components, and complex structural layouts. Due to adverse factors such as environmental loads, fatigue effects, and material aging, various defects will inevitably appear in bridges during long-term use, resulting in the accumulation of damage to local key components of the structure. If the decrease in stiffness and bearing capacity of the structure cannot b...

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Problems solved by technology

However, due to various defects in the long-term use of the bridge, the finite element model and structure established based on the design data have errors in boundary conditions, material and section parameters, mass and load distribution, etc., so the finite element model is difficult to accurately reflect the structure. Behavior and working state under the action of service load, it is necessary to correct the finite element model based on the response monitoring value of the health monitoring system, so as to conduct further safety assessment of the bridge through the corrected finite element model

[0004] At present, the dynamic response results such as test modal data are generally used to correct the finite element model of the steel bridge. Although the modal test based on environmental excitation is widely used in recent years, although it is safe and does not affect the normal use of the bridge, there are still many problems. Disadvantages: 1) There are unknown inputs in environmental excitation, such as various noise disturbances; 2) The identification of modal parameters is based on the assumption of modal theory; 3) The local response of the structure cannot be determined; 4) The requirements for accurate modal parameter identification are high, The amount of data processing is large, which is not conducive to the mastery of engineers; 5) The number of sensors is required to be large

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