利用标准曲线测定碾压混凝土中氧化镁掺量的方法探析

Analysis on the Method of Determining the Content of Magnesia in Roller compacted Concrete by Standard Curve

现行规范关于碾压混凝土中外掺氧化镁掺量的测定步骤繁琐、试验结果计算复杂,且测定掺量值与设计掺量值存在差异,无可比性。为此,该文特在原试验方法基础上进行改进,并提出了利用标准曲线测定碾压混凝土中氧化镁掺量的新方法。试验结果表明,新方法减少对试验结果计算干扰较大的水洗和过筛步骤,简化了氧化镁含量需直接测算的过程;以工程设计掺量6.5%为例,旧方法中氧化镁实测掺量范围为3.08%~4.95%,平均值为4.19%,新方法氧化镁实测掺量范围为5.22%~7.96%,平均值为6.46%,新方法掺量测定值与设计掺量保持一致,可准确反映实际掺量是否达到设计要求,便于科学客观评价工程施工质量,同时为现行规范的修订和完善提供参考依据。

In the current code,the steps for determining the content of magnesium oxide in roller compacted concrete are tedious,and the calculation of the test results is complex,and there is a difference between the measured content and the designed content,which is incomparable.For this reason,this paper makes an improvement on the basis of the original test method,and puts forward a new method for determining the content of magnesium oxide in roller compacted concrete by using the standard curve.The experimental results show that,compared with the old method,the new method reduces the steps of washing and sieving which interfere with the calculation of the test results,and simplifies the process of direct measurement of magnesium oxide content.Taking 6.5%of the engineering design content as an example,the measured content range of magnesium oxide in the old method is 3.08%to 4.95%,with an average of 4.19%,while in the new method,the measured content range is 5.22%to 7.96%,with an average of 6.46%.The measured value of the new method is consistent with the design content,which can accurately reflect whether the actual content meets the design content requirements,and is convenient for scientific and objective evaluation of project construction quality.At the same time,it provides a reference basis for the revision and improvement of the current norms.