钢管微膨胀混凝土的制备及其性能研究

Preparation and Performance Study of Steel Pipe Micro Expansion Concrete

钢管和混凝土两种材料的收缩性能不同,容易导致接触面脱离。掺加膨胀剂能够较好的抑制钢管和混凝土的脱离,但需要借助高吸水性树脂等内养护剂为膨胀剂的水化过程补给水分。本文以膨胀剂、高吸水树脂、硅灰的掺量为变量设计L9(33)正交试验,试验各组配合比下混凝土的力学性能和耐久性能,并采用功效函数法进行评估决策,结合主观赋权法和客观赋权法进行权重分配,计算并比较各方案的综合效益值,选择综合效益值最高的方案作为最优配合比。经筛选,最佳配合比(第H5组)的掺量组合为膨胀剂10%、高吸水树脂0.3%、硅灰6%。

The different shrinkage properties of steel pipes and concrete can easily lead to detach‐ment of the contact surface.The addition of expansion agents can effectively suppress the detachment of steel pipes and concrete,but it is necessary to use internal curing agents such as high absorbent resins to supplement water for the hydration process of expansion agents.This article designs L9(33)orthogonal experiments with the dosage of expansion agents,high absorption resins,and silica fume as variables to test the mechanical and durability properties of concrete under different mix proportions.The efficacy function method was used for evaluation and decision-making,and subjective and objective weighting methods were combined for weight distribution.The comprehensive benefit values of each scheme were calculated and compared,and the scheme with the highest comprehensive benefit value was selected as the optimal mix proportion.After screening,the optimal mix proportion(Group H5)had a dosage combination of 10%expansion agent,0.3%high absorbent resin,and 6%silica fume.