Load limit standard evaluation method for in-service concrete bridge

Abstract

The invention relates to a load limit standard evaluation method for an in-service concrete bridge. Uncertain factors such as a traffic volume increasing index, a large-tonnage vehicle mixing rate index and a percentage index of axle load exceeding 14 t in axle load distribution in automobile load effect evaluation indexes remarkably influencing a bridge load limiting standard are taken as evaluation indexes in an automobile load effect evaluation index set; the evaluation indexes are assumed to be random variables with certain probability distribution characteristics. Based on the obtained real-time traffic operation load data, a random simulation theory and a fuzzy mathematics concept are applied, random fuzzy evaluation is carried out on the vehicle load effect, the probability distribution characteristics of the vehicle load effect are obtained, and the reliability measurement and analysis of the in-service concrete bridge load limit standard are further realized, so that the uncertain influence on the measurement result caused by ignoring the randomness of the live load effect and the fuzziness of evaluation grade division in the existing highway bridge load limit standard measurement is overcome.

Description

Technical field [0001] The invention relates to the field of concrete bridges, in particular to a method for evaluating the load limit standard of in-service concrete bridges. Background technique [0002] With the increase of highway traffic flow and traffic load in our country, overweight transportation has seriously endangered the safety and durability of in-service bridges and is the main cause of structural damage to highway bridges. Among them, large freight vehicles such as coal transport vehicles, sand transport vehicles, and crude oil transport vehicles can be overloaded even several times the rated load, posing major safety hazards to the safe operation and durability of highway bridges. At the same time, a considerable part of the bridges in use in my country are in poor technical condition and are in a state of "working with illness". However, the repair and reinforcement of diseased bridges are often lagging behind, and proper load-limited traffic can effectively im...

AI Technical Summary

Problems solved by technology

The main problem of this measurement technology is that this method is a deterministic evaluation method based on the detection results of in-service bridges and combined with the investigation and statistics of bridge operating loads, which ignores the typical representative traffic volume of vehicles, the mixing rate of large-tonnage vehicles, axle loads, etc. The randomness of load distribution and other factors and the uncertainty of the graded model bring uncertainty to the evaluation results, resulting in large fluctuations in the measurement results of the load limiting capacity of in-service bridges, and the reliability of the measurement results is low.

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