JPH01500107A - Volume stable curing hydraulic cement - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Volume stable curing hydraulic cement field of invention The present invention relates to improvements in the composition of hydraulic cement. More specifically, the present invention Land cement, aluminate lime salt cement and sulfates, preferably calcium in cement consisting of a mixture of aluminum or aluminum sulfate or ceracola. related to improvements.

definition The term "hydraulic cement" used here refers to portland cement, expansive cement, Aentren Portland cement, volcanic ash mixed cement, slag cement, metal - Sonley cement, white portland cement, colored cement, antibacterial cement waterproof cement, fireproof cement, self-stress cement, alumina cement and similar substances shall be meant.

The term "ceracola" used includes ceracola as it is normally understood in the art. shall be held. This includes calcium sulfate (CaSo4) and its various forms. For example, calcium sulfate dehydrate, calcium sulfate hemihydrate, and calcium sulfate dihydrate. hydrates, as well as baked ceracola, pressure baked ceracola and baked ceracola (plas ter of Paris).

The term "alumina cement" used here refers to aluminic acid-calcium as the main cement component. Cement substances that are normally understood technically as containing siadium (Ca0xΔ1.0.) shall be included. This includes high alumina cement (HAC), aluminate lime salt Includes cement and many other commercially available alumina cements.

The term "Portland cement" used is usually "Portland cement". Cement, including those described in ASTM Standard C-150. shall be held. The Portland cement component of these cement mixtures undergoes drying shrinkage. It acts to reduce the moisture content and increase wet expansion. Acts as a drying shrinkage inhibitor, but Other cements not specifically designated as Rutland cements are also commonly used for this purpose. Therefore, the term ``Portland cement'' encompasses these other cements. It should be understood that Examples of drying shrinkage inhibitors include expansion promoters such as other components of the system. and expandable cement, which is mutually exclusive.

Background of the invention Meets the requirements of the construction industry, especially in the protection, waterproofing and repair of concrete structures Many previous attempts have been made in providing cementitious systems. Hard mass or coating with sufficient strength, wear resistance and corrosion resistance over time It should be concentrated in the group. These systems are impermeable to fluids, especially aqueous solutions. It is also highly desirable to There should not be excessive curing volume changes.

For commercial use, these types of cement systems have a good It must also have good bonding properties, initial and long-term strength, and field workability. , they withstand freezing and thawing as well as the action of salts, solvents and other corrosive substances A polyurethane material having one or more of the desirable properties listed above, which must be able to Although there are many cement mixtures, none of the prior art to date has failed to achieve all of the above, and precedents have had only limited success. stomach. U.S. Pat. No. 4,357,166 lists these prior art compositions in columns 2@ and 3. Discuss some of the constraints of things.

ing.

What is a mixture of portland cement, aluminate lime salt cement and ceracola? Although they have been used for years, various problems associated with their use have been encountered.

The foregoing compositions containing other hydraulic cements such as alumina cement and Sencora are 0, which have been shown to exhibit long-term wet expansion, e.g. in U.S. Pat. No. 4,357,166. When mixed with water, it rapidly sets into a hard mass with high compressive strength without substantial shrinkage during setting. A cement composition is disclosed that is capable of bonding and exhibits low wet and dry volume changes in the cured state. It is.

The invention also provides some impermeability to fluids and abrasion, erosion and chemical resistance. as well as other properties desired in a composition that has commercial utility in the construction industry. . The advantages of the invention are alumina cement, ceracola, drying shrinkage inhibitor and wet swelling This is achieved by a cement composition containing a mixture of tension suppressants. The composition of the invention is , preferably Portland cement as a drying shrinkage inhibitor and lithium salts. Used as a wet swelling inhibitor. However, various accelerators, retarders and other mixtures When a substance is added to alumina cement and Cefcola compositions, curing volume changes (wet and drying), thus limiting their usefulness. It will be done.

Additionally, previous attempts to mix Ceracola with other hydraulic cements have shown that the desired effect has not been achieved. for example, fast setting or low shrinkage, but also the stability and resistance of hydraulic cement. Durability, workability, water resistance or wetting/drying cycles of the resulting cement impact on stability or durability.

U.S. Pat. No. 4,045,237 teaches that when mixed with water, Congeals quickly into a hard mass without substantial shrinkage and is highly impermeable to fluids. Cement (cemen) &ll compositions that can be used are disclosed. Its composition is baked ceraco Contains powder mixtures of la, high alumina cement and portland cement, and It is made of high alumina cement and pressure baked without the use of portland cement. Contains a mixture of Ceracola particles.

Portland cement is mainly made from tricalcium silicate and dicalcium silicate. Become. Two types of raw materials are used to produce this formulation - one with a high calcium content e.g. limestone or chalk, and those rich in silica e.g. clay or chalk. roux is usually required. These raw materials usually contain significant concentrations of iron-retaining compounds do. The presence of these compounds during the heating process is in the form of talincar containing a few percent of iron oxide. produce a result.

The structure of this Portland cement clinker is therefore dependent on the raw material composition and particle size. Due to variations and inconsistencies in firing conditions, it varies significantly and Variations in porosity and differences in crystal size and morphology found in crystallite aggregates arise.

Accordingly, as disclosed in U.S. Pat. The Portland cement component of the cement composition was For example, in U.S. Pat. No. 4,045,237, a mixture containing iron oxide of It is critical to use 0.1-10% Portland cement in it. 10 If more than % of Portland cement is added, Portland cement - Baked Sencola - Cement hydration resistance due to the proportion of ferric oxide occurring in high alumina cement mixtures. This may cause difficulties.

U.S. Patent No. 4,157,263 led to the issuance of the No. 4.045.237 patent. No. 4.045.237, which contains the compositions claimed in the No. 4.045.237 patent. Use in the repair and waterproofing of reed structures and for the stability of machinery or heavy equipment. Discloses a method for filling voids or holes to form a foundation or foundation. Ru. The amount of Portland cement used in carrying out this method is considerable, as mentioned above. contains ferric oxide, which can be added to the mixture and thus reduce the strength of the composition Constrain the amount of portland cement.

Applicants are interested in Calcium Sulfate Hemihydrate, Aluminate Lime Salt Cement and Portolan Concrete, grout, punching substances and The hardening volume changes that occur in waterproofing and waterproofing materials can be reduced by using Portland cement containing low levels of iron oxide. It has been found that this can be reduced by using Applicant further states that Such a reduction in the iron oxide used in the component component results in a surprising increase in the compressive strength of this composition. increasing and improving its bonding ability to previously set concrete. confirmed.

The maximum iron oxide content can vary, but as a general rule it should be up to about 2% by weight. Preferably the iron oxide content should be as low as possible, but in practice As a practical matter, amounts below 0.1% by weight are difficult to achieve.

Summary of the invention This invention relates to improvements in hydraulic cement compositions. More specifically, the present invention Portland cement, aluminate lime salt cement and calcium or alkali This invention relates to improvements in cements comprising blends of minium sulfate compounds.

The compositions disclosed by applicants contain low levels of iron compounds such that they have low iron oxide content. About 0.1 to about 80 parts by weight of Portland cement manufactured from raw materials containing sulfuric acid a salt compound, preferably from about 0.1 to about 40 parts by weight of Ceracola and about alumina cement. The most advantageous compositions contain from about 2 to about 95 parts by weight of low iron Portland cement. 20 parts by weight, 55 to 95 parts by weight of alumina cement, and 2 to 10 parts by weight of Ceracola. including.

Although any sulfate compound can be used in the present invention, organic or inorganic salts are preferred. Calcium sulfate gives the best results and can be used as a pure chemical, formed in situ, or its usual form, addition in cefcola is most advantageous. sulfuric acid Ammonium aluminum (AfNHa(SOa)t) and potassium sulfate Luminium CAj! K(SO4)z) also gives good results. other arcas metal sulfates have not been found to be useful, and satisfactory performance has been ) is only observed in aluminum sulfate. Based on availability, Senkora has various The most preferred sulfate compound is in the form of .

The most preferred compound, calcium sulfate, is combined with e.g. sodium sulfate and calcium nitrate. It is also possible to form the mixture in situ by reaction of the mixture with a rubber. various sulfates Other calcium compounds that are reacted with can be used.

In one embodiment of the cement composition, the maximum iron oxide content of the Portland cement is A 2% by weight, determined as ferric oxide by STM test method C-114. other In embodiments, the Cefcola selected for use in Applicants' compositions is calcium sulfate. It is a hemihydrate.

Applicant's compositions may further include many other ingredients and additives, and the composition The total weight of Portland cement, sulfate compounds and alumina cement in the It can contain up to about 90% by weight of aggregate. Additional ingredients may come into contact with water. Contains compounds that can generate gas when You can

Applicants' volume stable cement compositions therefore have a maximum iron oxide content of 2% by weight. about 0.1 to about 80 parts by weight, preferably 2 to 20 parts by weight of Portland cement; f about 0.1 to about 40 parts by weight, preferably 2 to 10 parts by weight of the L salt compound; and It contains from about 2 to about 95 parts by weight, preferably from 55 to 95 parts by weight, of minacement.

Applicant also claims that raw materials containing low levels of iron compounds, such as containing less than about 2% iron oxide, about 0.1 to about 80 parts by weight of Portland cement manufactured from calcium or about 11 to about 40 parts by weight of aluminum sulfate compound; and about alumina cement. A mixture containing 2 to about 95 parts by weight is mixed for a predetermined duration, and then the mixture is mixed with water. Discovered a new method of manufacturing and manufacturing volume-stable cement compositions, including hydration Ta.

The method developed by the applicant involves applying portolan to the mixture before hydrating it with water. Based on the total weight of cement, sulfate compound and alumina cement, from about 1 to about Some additional steps may be included including adding aggregate in an amount of 90 parts by weight.

Additionally, the mixture may contain at least one accelerator, retardant, pigment, water reducer or gas generant. You can also add one type.

The products resulting from the practice of the process disclosed herein by applicants are also novel. It should be considered as part of this invention.

Improvements in cement compositions disclosed by applicants provide improved volumetric stability. , high strength and good bonding strength to other cement compositions. Improvements include controlling the maximum iron content of Rutland cement to about 2% by weight. Furthermore, by reducing the iron oxide content of cement to the lowest possible value, This includes reducing the setting time of. The iron oxide content in Applicant's composition is 0. It should be within the range of 1-2 double vision devices.

Detailed description of preferred embodiments The following examples illustrate, without limitation, the novel cement compositions of the present invention and their advantages. In 0 examples given for illustration, parts and percentages are by weight unless otherwise indicated. .

Example 1 Aluminate lime salt cement, 6FLflll calcium hemihydrate and Portolan Portland cement contains a "normal" amount of ferric oxide, about 23% A composition prepared from a formulation containing %.

Nee-ri 1-oka, tri-blend the following ingredients for 1 minute. portland cement 8 Aluminate lime salt cement 25 Calcium sulfate hemihydrate 5 Dried fried coke 3 Melment (Mel+went) F 10 0.5 Lithium carbonate 0.09 Citric acid 0.12 Sand 58.29 After dry mixing, 12.5 parts of water was added to hydrate the mixture and the following properties were measured: time compressive strength 1 hour 900psi 3 hours 3,0OOps+ 24 hours 6,300psi Shrinkage and expansion tests were conducted on 11 inch specimen castings cured from the compositions: Drying shrinkage = 0.0196% (after 14 days storage at 50% humidity) Wet expansion - 0,013 0% (after immersion in water) Example 2 The same ingredients were used in the same proportions as found in Example 1. But in this example Porto Land cement is manufactured from raw materials containing low levels of iron compounds and contains 0.4 ferric oxides. % by weight.

After hydration of the composition, the following improvements were shown compared to the values of Example 1: time compressive strength 1 hour 4,500psi 3 hours 9.000psi 24 hours 11. OO0psi Drying shrinkage = O,0O03% (after 14 days storage at 50% humidity) Wet expansion = 0.000 4% (after immersion in water) 50% increase in bond strength compared to the composition described in Example 1 and A surprising reduction in water absorption and permeability of the hydrated products was also demonstrated.

Examples 3 and 4 further demonstrate the improvements provided by low iron oxide Portland cement.

The following ingredients were triblended for 1 minute in Example 3: Example 3 Object -j1! %- portland cement 8 Aluminate lime salt cement 25 Calcium sulfate hemihydrate 5 Dried fried coke 3 Melment F-100,5 Sand 58.5 As in Example 1, the Portland cement contains approximately 23% by weight ferric oxide. did. After dry mixing, 12.5% water was added to hydrate the mixture and the following properties were measured: Ta: −1”υ”−−π 3 hours 975psi 24 hours 8,525psi 7th day 9.500ps+ Dry shrinkage = 0.0736% (after 28 days storage at 50% relative humidity) Wet expansion = immersed in water The test piece was destroyed when immersed in the water, so it could not be measured.

Example 4 The ingredients used in Example 3 were again used in the same proportions. But in this example, Portland Cement was manufactured from raw materials containing low levels of iron compounds as in Example 2 (i.e. In other words, ferric oxide content: 0.4% by weight).

After hydration of the composition, the following improvements were shown compared to the values of Example 3: time - pressure j1 - 3 hours 5,750psi 24 hours 8.925psi 7th day 1 1. 0 7 5 ps+ Dry shrinkage = 0.04% (after 28 days at 50% relative humidity) Wet expansion = 0.0073 % (after 28 days of immersion in water) Although any Ceracola can be utilized in these formulations , Calcium sulfate semi-aqueous phase was used in 0 cases where it was found to give the most effective results. Melment F-10 compound is well known as a water reducing agent. , AmericanAdmixtures *Available from Chicago + l1linois). Other water reducing agents It can be used for non-inventive purposes.

In addition to the three essential components of the cement composition of the present invention, ordinary Of course, additives can also be used. This includes promoters, retarders, pigments, -E agents, water reducing agents, bombing aids, fly ash, gas generating and releasing agents, Also, of course, includes, but is not limited to, a full range of aggregates.

The invention disclosed herein provides improved cement systems over those described in the prior art. Although it is clear that Mr. B is considering providing It will be appreciated that claims can be devised by It is intended to cover all modifications or embodiments that fall within the true spirit and scope of the invention. do.

Procedural amendment (formality) %formula% 2. Title of the invention Volume-stable hardening hydraulic cement 3. Person making the amendment Relationship to the case: Applicant 4. Agent international search report

Claims (9)

[Claims] Bortland cement, alumina cement with a maximum iron oxide content of 1.2% by weight and volume-stable cements containing calcium or aluminum sulfate compounds. Composition. 2. Voltland cement is present in an amount of 0.1 to 80 parts by weight, alumina cement is present in an amount of 2 to 95 parts by weight, and the sulfate compound is present in an amount of 0.1 to 40 parts by weight. A composition according to claim 1, wherein the composition comprises: 3. Voltland cement is present in an amount of 2 to 20 parts by weight, and alumina cement is present. present in an amount of 55 to 95 parts by weight and the sulfate compound present in an amount of 2 to 10 parts by weight. , the composition according to claim 1. 4. Claim 1, 2 or 3, wherein the sulfate compound is gypsum. composition. 5. Sulfate compounds include aluminum sulfate such as ammonium aluminum sulfate or aluminum sulfate. is potassium aluminum sulfate, according to claim 1, 2 or 3. composition. 6. Claims 1, 2 or 2, wherein the sulfate compound is calcium sulfate. Composition according to item 3. 7. Calcium sulfate compounds react with alkali metal sulfates and calcium nitrate. 7. The composition of claim 6, wherein the composition is formed in situ into a composition. 8. Further comprising 1 to 90 parts by weight of aggregate or filler component. Composition according to any one of clause 7. 9. Additionally, one of a gas generating agent, a surfactant, a water reducing agent, or a setting time controlling agent, or The composition according to any one of claims 1 to 8, comprising more than or equal to the above.