阅读说明：本技术 一种基准萘系外加剂以及用于水泥性能评价的方法 (Benchmark naphthalene additive and method for evaluating cement performance ) 是由 白明科 李海宏 赵健 于 2018-06-20 设计创作，主要内容包括：本发明提供一种基准萘系外加剂以及用于水泥性能评价的方法。所述基准萘系外加剂以重量百分比计,由以下成分组成：萘系外加剂母料：20～40％,缓凝剂：1～3％,引气剂：0.05～0.2％,水：60～80％。本发明提供的基准萘系外加剂,与水泥适应性良好,质量稳定且可靠,能够及时、有效地评价水泥与外加剂的适应性和混凝土的工作性能。(The invention provides a reference naphthalene additive and a method for evaluating cement performance. The reference naphthalene additive comprises the following components in percentage by weight: naphthalene additive master batch: 20-40%, retarder: 1-3%, air entraining agent: 0.05-0.2%, water: 60-80%. The reference naphthalene additive provided by the invention has good adaptability with cement, stable and reliable quality, and can effectively evaluate the adaptability of cement and the additive and the working performance of concrete in time.)

1. A benchmark naphthalene additive is characterized in that: the paint consists of the following components in percentage by weight: naphthalene additive master batch: 20-40%, retarder: 1-3%, air entraining agent: 0.05-0.2%, water: 60-80%.

2. The baseline naphthalene additive of claim 1, wherein: preferably, the purity of the retarder is more than or equal to 98 percent.

3. The baseline naphthalene additive of claim 1, wherein: the naphthalene additive master batch is FDN, and the solid content is more than 92%.

4. The baseline naphthalene additive of claim 1, wherein: the retarder is any one of white sugar, molasses, citric acid, sodium phosphate and sodium gluconate.

5. The baseline naphthalene additive of claim 1, wherein: the air entraining agent is any one of sodium dodecyl benzene sulfonate, triterpenoid saponin and dodecyl benzene sulfonic acid.

6. The method for preparing the benchmark naphthalene additive of any one of claims 1 to 5, which is characterized by comprising the following steps: the components are mixed according to the proportion, and the finished product can be obtained after the components are uniformly stirred and dispersed.

7. The method for evaluating the properties of cement using the benchmark naphthalene additive according to any one of claims 1 to 5, it is characterized in that the reference P.042.5 cement and the reference naphthalene additive are stirred and mixed evenly according to the proportion, then slowly pouring the slurry into a round mould positioned in the middle of the glass plate to ensure that the round mould is slowly filled with the slurry, scraping and leveling the slurry higher than the top surface of the round die by a scraper, immediately lifting the round die for about 1min, measuring the length of the longest diameter direction of the elliptic slurry and the length of the elliptic slurry in the vertical direction by using a vernier caliper, averaging the longest diameter direction and the length of the elliptic slurry in the vertical direction to obtain initial fluidity, immediately recovering the slurry on the glass plate into a specified container after the initial fluidity is measured, sealing the container mouth with preservative film to prevent water loss, stirring again after 30min and 60min, and measuring the fluidity of the slurry after 30min and 60 min.

8. The method of claim 7, wherein: the dosage of the reference naphthalene additive is 1.0-3.0% of the dosage of the cement.

Technical Field

The invention relates to a reference naphthalene additive and a method for evaluating cement performance, belonging to the technical field of building materials.

Background

With the continuous development of the construction industry, the requirements of the construction industry on high retention, durability, adaptability and construction performance of cement are higher and higher, and higher requirements are also provided for the additive which is an important component of concrete. For the admixture, besides good use effect (such as the water reducing agent should have the effects of improving cement strength, reducing mixing water consumption and saving cement consumption), the admixture also needs to have good adaptability with cement. However, in the using process, the varieties and the types of the additives on the market are various, the respective qualities of the additives are different, and even the additives produced by different manufacturers with the same brand and the different types are greatly different. The water reducing rate of the admixture used by the laboratories of part of key projects and commercial mixing stations is low and the quality is unstable, so that the cement performance is misjudged when the admixture is used for testing the adaptability of the cement. When the components, varieties or manufacturers of the additives used in key projects or commercial mixing stations change, the adaptability of the additives and cement fluctuates and changes, so that the judgment result of the cement performance is influenced. The problem of poor adaptability of the admixture and the cement is very common, and great inconvenience is brought to lean production of the cement.

If no uniform additive product is used for measuring and judging the adaptability of the cement and the additive, the fluctuation condition of the cement quality cannot be mastered in advance, and the increasing demand of the market on high-quality cement cannot be met. Therefore, cement manufacturers urgently want to evaluate the adaptability of cement and additives by preparing an additive formula which has good adaptability with cement and stable and reliable quality as a reference.

Disclosure of Invention

In view of the above problems of the existing admixtures, the present invention provides a reference naphthalene admixture for evaluating the adaptability of cement and admixture.

One aspect of the invention provides a reference naphthalene additive, which has the following specific technical scheme:

a reference naphthalene additive comprises the following components in percentage by weight: naphthalene additive master batch: 20-40%, retarder: 1-3%, air entraining agent: 0.05-0.2%, water: 60-80%.

Further preferably, the purity of the retarder is more than or equal to 98%.

Further preferably, the naphthalene additive master batch is FDN, and the solid content is more than 92%.

Further preferably, the retarder is any one of white sugar, molasses, citric acid, sodium phosphate and sodium gluconate.

Further preferably, the air-entraining agent is any one of sodium dodecyl benzene sulfonate, triterpenoid saponin and dodecyl benzene sulfonic acid.

The preparation process of the reference naphthalene additive comprises the following steps: the naphthalene series admixture master batch, the retarder and the air entraining agent are uniformly mixed, and are fully dissolved and uniformly stirred after water is added to obtain a finished product.

In another aspect of the present invention, a method for evaluating cement is provided.

The saturated doping amount point of the benchmark additive is determined by adopting a clean slurry fluidity method (substitution method) test in JC/T1083-. Specifically, the cement and the naphthalene additive are stirred and mixed uniformly according to a proportion, then the slurry is slowly poured into a round die positioned in the middle of a glass plate to slowly fill the round die with the slurry, then the slurry higher than the top surface of the round die is scraped and smoothed by a scraper, the round die is lifted immediately, after about 1min, the length of the longest diameter direction of the oval slurry and the length of the longest diameter direction of the oval slurry in the vertical direction are measured by a vernier caliper, the two are averaged to obtain initial fluidity, after the initial fluidity is measured, the slurry on the glass plate is immediately recovered to a specified container, and the container opening is sealed by a preservative film to prevent moisture from losing. And re-stirring after 30min and 60min, and sequentially measuring the fluidity of the slurry under each mixing amount after 30min and 60min according to the method.

Preferably, the dosage of the reference naphthalene additive is 1.0-3.0% of the dosage of the cement.

The technical indexes of the cement obtained by mixing the reference naphthalene additive and the reference P.042.5 cement in proportion are shown in Table 1:

TABLE 1 technical index of cement obtained by mixing reference naphthalene additive and reference P.042.5 cement in proportion

The doping amount of the additive is an abscissa, the fluidity of the cement paste is an ordinate, a curve graph is drawn, then trend lines of curves of two straight line segments are drawn, and the abscissa of the focus of the two trend lines is a saturated doping amount point. The saturated adding amount point of the reference naphthalene additive is shown in the attached drawing of the specification. The initial saturation point doping amount of the reference naphthalene additive is 1.9 percent, the 30min saturation point doping amount is 2.45 percent, the 60min saturation point doping amount is 2.4 percent, and the final average additive saturation point doping amount is 2.3 percent of the mass of the cement.

The control standard is determined according to the compatibility test of the cement and the admixture and the saturated mixing amount point as follows: the initial fluidity of the cement paste is more than or equal to 200mm, the fluidity of the cement paste is more than or equal to 180mm after 30min, and the fluidity of the cement paste is more than or equal to 150mm after 60 min.

The invention has at least the following beneficial effects: the additive has the characteristics of high water reducing rate, stable quality, good cement adaptability and the like, and can be used as an efficient standard additive for evaluating the cement adaptability.

Drawings

FIG. 1 is a graph showing the trend of the saturated loading point of a reference naphthalene additive.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to fig. 1 and the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

The reference naphthalene additive comprises the following components in percentage by weight: naphthalene additive master batch: 20-40%, retarder: 1-3%, air entraining agent: 0.05-0.2%, water: 60-80%.

To evaluate the performance of the baseline naphthalene based admixture of the present invention, the following examples were conducted: