Entity component external constraint degree evaluation method based on overall deformation monitoring

Abstract

The invention discloses a solid member external constraint degree evaluation method based on overall deformation monitoring, and the method comprises the following steps: (1) pre-burying temperature sensors inside and on the surface of a concrete solid member, and calculating the average temperature of the solid member; (2) calculating free deformation [epsilon]1t caused by temperature reduction of the solid component according to a temperature monitoring result; (3) forming a concrete test piece according to the concrete mix proportion and the reinforcement ratio of the solid component, and calculating free deformation [epsilon]1s caused by self-shrinkage and dry shrinkage; (4) calculating the total free deformation epsilon 1 of the solid structure according to [epsilon]1t and [epsilon]1s; (5) actually measuring actual deformation epsilon2 of the solid component at different ages after pouring on site; (6) taking a difference value between the total free deformation epsilon1 and the actual deformation epsilon2 as a constraint deformation epsilon3; (7) solving the constraint degree R of the solid structure. According to the method, the accuracy of early-stage constraint stress calculation of the concrete structure is improved, and support is provided for formulation of crack control measures of the concrete structure.

Description

technical field [0001] The invention relates to the technical field of cracking risk assessment of concrete structures, in particular to a method for evaluating the external restraint degree of concrete structures. [0002] technical background [0003] A large number of engineering crack investigation results show that 80% to 90% of the cracks in concrete structures, especially in super-long volume concrete structures, are due to the external constraints of concrete cooling shrinkage and dry shrinkage, and the resulting constraining stress exceeds the ultimate tensile strength of concrete. It is caused by the constrained tensile strain of the concrete exceeding the ultimate tensile strength of the concrete. [0004] According to the Chinese standard "Construction Standard for Mass Concrete" (GB 50496-2018), the deformation of the component is constrained by the bottom, end or side and the external restraint stress and the free deformation, elastic modulus, degree of restrain...

AI Technical Summary

Problems solved by technology

[0018] Regardless of whether the calculation method of the degree of restraint is given according to the Chinese standard or the empirical value of the degree of restraint given by the European standard, only the empirical range of the degree of restraint can be obtained. When calculating the tensile stress of a solid structure, there is a large gap Deviation, which affects the accuracy of the assessment results of concrete structure cracking risk

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