Abstract

In order to improve the accuracy of the analysis of the impact of freeze–thaw cycle on concrete durability in a salt freezing environment, the numerical simulation of the impact of the freeze–thaw cycle on concrete durability in a salt freezing erosion environment is studied in this paper. Firstly, considering the influence of axial force and bending moment on the relationship between bending moment and curvature, a concrete fiber beam column model is established. Then, according to the joint influence of temperature field, stress field and seepage field on concrete in the process of freezing and thawing, the control differential equation of the freezing and thawing cycle is established. The freeze–thaw damage section is divided, the non-uniform distribution of freeze–thaw damage is determined, and the division of the freeze–thaw damage section is completed. According to the linear relationship between freeze–thaw damage degree, relative dynamic elastic modulus, freeze–thaw cycle times and position variables, the durability of concrete is numerically simulated, and the attenuation law of bond strength at different section depths after freeze–thaw is determined. The results show that the temperature curve simulated by the design method is consistent with the actually measured temperature curve, which can better reduce the temperature change of the inner core of the test block during freezing and thawing, and the relative dynamic elastic modulus is in good agreement with the actual value, which can prove that the method in this paper has certain practical application value. It is expected to provide some reference for solving the durability problem of concrete in a salt frost erosion environment and the optimal design of concrete structures.

Highlights

  • Various causes have led concrete structures to suffer from destruction, collapse and other material durability problems in the past 40 or 50 years, seriously affecting the normal benefits and safe use of these structures [1]

  • Under the combined action of salt erosion and freeze–thaw and other environmental factors, the damage to concrete structures in irrigation areas is very serious, and a considerable number of concrete structures lose their functions prematurely before reaching the designed lifetime, which has a big impact on the safety and benefits of water projects

  • When the concrete structure is in a working environment with freeze–thaw in winter, it will suffer from the combined action and linkage damage of two or more elements

Read more

Summary

Introduction

Various causes have led concrete structures to suffer from destruction, collapse and other material durability problems in the past 40 or 50 years, seriously affecting the normal benefits and safe use of these structures [1]. In order to alleviate freeze–thaw damage, scholars have proposed various mitigation methods, such as adding creto material, changing the mix proportion parameters and the connection type of foundation parts, and using freeze–thawand corrosion-resistant materials [3,4,5,6,7] These mitigation methods have been proposed, in order to improve the pertinence of mitigation methods, it is necessary to analyze the impact of the melting cycle on concrete durability. Taking a long highway tunnel with a shotcrete single-layer permanent lining in a cold area as the engineering background, the pore structure of concrete under the combined action of nitric acid erosion and the freeze–thaw cycle was characterized and analyzed by means of the straight-line conductor method [8]. Because the freeze–thaw cycle mainly affects the mechanical properties of concrete, the same selection method is adopted for the constitutive model of steel bars of freeze–thaw and non-freeze–thaw specimens

Governing Differential Equations of Freeze Thaw Cycles
Division of Freeze–Thaw Damage Section Based on Coupling Algorithm
Numerical Simulation of Concrete Durability
Findings
Experimental Analysis of Temperature Shock Field
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call