聚羧酸系减水剂减水率的快速测定方法研究

发布时间：2018-04-13 01:26

本文选题：胶砂法 + 减水率　；参考：《云南大学》2015年硕士论文

【摘要】：减水率是减水剂的一项重要指标,它一般用来表征减水剂的作用效果。目前减水率主要是根据国家规范由实验室测得。然而实验室测定减水率时对原材料均有特殊要求,造成施工现场的实际减水率与实验室测定的减水率产生偏差。因此,施工现场迫切的需要一个可以快速准确且能够反映出实际拌合物中减水剂减水率的试验方法。本文着重对国标胶砂法进行研究和讨论。分别研究了混凝土原材料中胶凝材料、砂对减水率的影响,初步得出了一个可以快速准确测定减水率的方法。研究结果表明：水泥与减水剂的相容性对减水率有直接影响。随着矿粉掺量的增加,减水率呈不断增大的趋势。当粉煤灰掺量在0-30%时,减水率随着粉煤灰掺量的增加而增加；当粉煤灰掺量高于30%时,随着粉煤灰掺量的增加减水率几乎没有变化。砂的细度模数对减水率的影响很明显,而砂的种类对减水率的影响相对较小。当砂中含有泥粉、石粉时,减水率有减小的趋势。根据以上试验结果可以初步提出一个快速测定减水剂减水率的试验方法：当砂各级配区满足特定的质量比、水泥与减水剂满足相容性良好的条件,根据砂的种类、细度模数,选择一个合理的砂胶比。采用这个砂胶比,利用水泥胶砂测定减水剂减水率。若砂的细度模数不在规定范围内,需进行简单的筛分。该方法中,砂的含泥量需要在2%以内,含粉量需要在12%以内。若超出范围,则需对砂进行冲洗,直至其达到标准以内。
[Abstract]:Water reducing rate is an important index of water reducing agent, which is generally used to characterize the effect of water reducing agent.At present, the water reduction rate is mainly measured by the laboratory according to the national norms.However, there are special requirements for raw materials when measuring the water reduction rate in the laboratory, which results in the deviation between the actual water reduction rate in the construction site and the water reduction rate measured in the laboratory.Therefore, there is an urgent need for a rapid and accurate test method that can reflect the water reducing rate of the water reducer in the actual mixture.This paper focuses on the study and discussion of the GB-standard cementing sand method.The influence of cement material and sand on water reduction rate in concrete raw materials was studied, and a method to measure water reduction rate quickly and accurately was obtained.The results show that the compatibility of cement and superplasticizer has a direct effect on the water reducing rate.With the increase of mineral powder content, the water reduction rate is increasing.When the content of fly ash is 0-30%, the water reduction rate increases with the increase of the content of fly ash, and when the content of fly ash is higher than 30%, the water reduction rate almost does not change with the increase of the content of fly ash.The influence of sand fineness modulus on water reduction rate is obvious, but the effect of sand type on water reduction rate is relatively small.When the sand contains mud powder and stone powder, the water reduction rate tends to decrease.According to the above test results, we can put forward a test method to measure the water reducing rate of water reducer: if the sand distribution area meets the specific mass ratio, the cement and the water reducer meet the good compatibility condition, according to the type of sand, the fineness modulus,Select a reasonable sand / binder ratio.Using this ratio of sand and binder, cement sand is used to measure the water reducing rate of superplasticizer.If the fineness modulus of sand is not within the specified range, simple screening is required.In this method, the mud content of sand should be less than 2%, and the content of powder should be less than 12%.If out of range, the sand must be washed until it reaches the standard.
【学位授予单位】：云南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU528.042.2

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