Prestressed concrete structure effective stress distribution evaluation method based on limited data

Abstract

The invention discloses a finite data-based effective stress distribution evaluation method for a prestressed concrete structure. The method comprises the following steps of: calculating theoretical distribution characteristics of an effective stress probability of an ith prestressed tendon of an existing concrete structure; centralizing the probability of the effective stress of the ith prestressed tendon; establishing a Gaussian mixture model; calculating skewness and kurtosis of the Gaussian mixture model; performing normal saliency test on the Gaussian mixture model and determining a detection range; detecting the effective stress value of the pre-stressed tendon of the existing structure; estimating the total effective stress probability of the prestressed member set; and estimating the effective stress probability of each component of the prestressed tendon.

Description

technical field [0001] The invention relates to the technical field of prestressed concrete structures, in particular to a method for evaluating effective stress distribution of prestressed concrete structures based on limited data. Background technique [0002] The effective stress of a prestressed concrete structure is the residual stress value after deducting various prestress losses from the stress at the tensile end of the prestressed tendon immediately before the anchorage. One of the key indicators of performance evaluation. [0003] The deterministic calculation method of prestress loss considering the influence of anchoring moment and long-term service is given in the codes of buildings, bridges and other structures. However, during the tensioning and service process of prestressed tendons, due to the randomness of construction, material, design and other parameters, the real effective stress of prestressed tendons is uncertain. Values ​​tend to vary widely. In a...

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Problems solved by technology

However, during the process of tensioning and service, prestressed tendons are affected by the randomness of parameters such as construction, materials, and design, so that there is uncertainty in the real effective stress. Values ​​tend to deviate greatly from

In addition, the prestressed system of the prestressed concrete frame structure is often composed of thousands or even tens of thousands of prestressed tendons. Stress loss, its effective stress distribution presents certain non-uniform characteristics

[0004] The post-tensioned prestressed concrete frame structure has a large number of prestressed tendons, and the effective stress is uncertain and unevenly distributed

It is impossible to fully evaluate the effective stress of all prestressed tendons of the structure even after sampling inspection

However, the existing method of evaluating the effective stress based on the mean value has certain safety hazards.

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