Concrete creep strain calculation method

Abstract

The invention relates to the technical field of bridge engineering, in particular to a concrete creep strain calculation method. The method comprises the following steps that 1, a creep coefficient phi(t, tau0) of concrete from the moment tau 0 loaded to the moment t and an elasticity modulus E(t, tau 0) are calculated; 2, an elasticity modulus E(t, tau 0) of concrete from the moment tau 0 loaded to the moment t is calculated; 3, according to the steps 1 and 2, a concrete creep strain calculation equation is obtained, and the equation is applied for calculating concrete creep strain, the calculation equation is shown in the description, the elasticity modulus E(t, tau 0) is obtained according to an aging coefficient, the elasticity modulus E(t, tau 0) is an effective modulus adjusted according to ages, and the expression is shown in the description. According to the method, the modulus is reduced, deformation modulus caused by concrete creep is achieved, strain changing along with time can be applied to concrete in one step, and therefore the problem that an effective modulus method overstates creep strain caused by stress increment obtained after loading is performed for the first time is solved.

Description

technical field [0001] The invention relates to the technical field of bridge engineering, in particular to a calculation method for creep strain of concrete. Background technique [0002] In recent years, my country's railway construction has developed rapidly. During the railway construction process, many railway continuous steel bridges have been newly built. According to the investigation, it is found that the mid-span deflection of the high-pier long-span continuous steel bridge continues to increase several years after the bridge is completed, exceeding the expected value at the time of design, affecting the driving comfort and causing adverse effects on the structure. impact, reducing the durability of the structure, and even leading to bridge failure. Studies have shown that shrinkage and creep are one of the important reasons for the continuous deflection of long-span continuous steel bridges. It has attracted the attention of scholars at home and abroad, but it h...

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Problems solved by technology

[0004] The purpose of the present invention is to provide a concrete creep strain calculation method for the problem of overestimating the creep deformation caused by the stress increment after the first loading in the prior art using the effective modulus method. The method realizes the deformation modulus caused by the creep of concrete through the reduction of the modulus, and regards the stress changing with time as one-step application on the concrete, thus solving the problem caused by the overestimation of the stress increment after the first loading by the effective modulus method The creep deformation of the problem

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