US4419136A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Expansive cement
Assignee: CHEMCOMP SYSTEMS
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Filing: 1982-02-10
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Granted: 1983-12-06
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Expires: 2002-02-10
Abstract
Abstract An improved expansive cement and method of forming same. An expansive clinker containing a stable calcium alumino sulfate compound is separately ground to a selected surface area greater than about 4600 sq. cm/gm. The ground expansive clinker is then blended with a ground cement clinker and with gypsum to form the expansive cement. The expansive cement formed in accordance with the present invention requires less of the expansive clinker than expansive cements known in the art to achieve the same magnitude of expansion.
Inventors
- 👤 Edward K. Rice
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 02:06
CPC Classifications
C; C04; C04B; C04B7/00; C04B7/32; C04B7/323
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
55 words
A method of forming an improved expansive cement comprising: separately grinding an expansive clinker containing a stable calcium alumino sulfate compound to a controlled particle size having a selected surface area greater than about 4600 sq. cm/gm; and blending said expansive clinker with a ground cement clinker and with gypsum to form said expansive cement.
Claim 2
Independent Claim
55 words
A method of forming an improved expansive cement comprising: separately grinding an expansive clinker containing a stable calcium alumino sulfate compound to a controlled particle size having a selected surface area greater than about 4600 sq. cm/gm; and blending said expansive clinker with a ground cement clinker and with gypsum to form said expansive cement.
Claim 3
Dependent Claim
46 words
A method of forming an improved expansive cement as in claim 1 wherein the calcium alumino sulfate compound comprises less than about 40 percent by weight of said expansive clinker, and said expansive clinker comprises from about 4 to about 9% by weight of said cement.
Claim 4
Dependent Claim
27 words
A method of forming an improved expansive cement as in claim 2 wherein said gypsum comprises from about 4 to about 10% by weight of said cement.
Claim 5
Dependent Claim
52 words
A method of forming an improved expansive cement as in claim 1 wherein said expansive clinker is ground to a surface area of from about 5000 sq. cm/gm to about 7500 sq. cm/gm and said cement clinker has a surface area of from about 3000 sq. cm/gm to about 6200 sq. cm/gm.
Claim 6
Independent Claim
96 words
A method of forming an improved expansion cement comprising: separately grinding an expansive clinker containing less than about 40% by weight of a stable calcium alumino sulfate compound until said clinker has a controlled particle size and selected surface area of from about 5000 to about 7500 sq. cm/gm; blending said expansive clinker with a ground cement clinker and with gypsum to form said expansive cement, said expansive clinker comprising from about 4 to about 9% by weight of said cement and said gypsum comprising from about 4% to about 10% by weight of said cement.
Claim 7
Independent Claim
96 words
A method of forming an improved expansion cement comprising: separately grinding an expansive clinker containing less than about 40% by weight of a stable calcium alumino sulfate compound until said clinker has a controlled particle size and selected surface area of from about 5000 to about 7500 sq. cm/gm; blending said expansive clinker with a ground cement clinker and with gypsum to form said expansive cement, said expansive clinker comprising from about 4 to about 9% by weight of said cement and said gypsum comprising from about 4% to about 10% by weight of said cement.
Claim 8
Dependent Claim
67 words
An improved expansive cement comprising a cement clinker, an expansive clinker containing a stable calcium alumino sulfate compound, and gypsum, said cement clinker and said expansive clinker being separately ground to a selected surface area before said clinkers are blended together with said gypsum to form said cement, said ground expansive clinker having a controlled particle size and selected surface area greater than about 4600 sq. cm/gm.
Claim 9
Dependent Claim
67 words
An improved expansive cement comprising a cement clinker, an expansive clinker containing a stable calcium alumino sulfate compound, and gypsum, said cement clinker and said expansive clinker being separately ground to a selected surface area before said clinkers are blended together with said gypsum to form said cement, said ground expansive clinker having a controlled particle size and selected surface area greater than about 4600 sq. cm/gm.
Claim 10
Dependent Claim
43 words
An improved expansive cement as set forth in claim 6 wherein the calcium alumino sulfate compound comprises less than about 40% by weight of said expansive clinker, and said expansive clinker comprises from about 4 to about 9% by weight of said cement.
Claim 11
Dependent Claim
25 words
An improved expansive cement as set forth in claim 7 wherein said gypsum comprises from about 4 to about 10% by weight of said cement.
Claim 12
Dependent Claim
52 words
An improved expansive cement as set forth in claim 6 wherein said expansive clinker is ground to a surface area of from about 5000 sq. cm/gm to about 7500 sq. cm/gm and said cement clinker is ground to a surface area of from about 3000 sq. cm/gm to about 6200 sq. cm/gm.
Claim 13
Dependent Claim
116 words
An improved expansive cement comprising a blend of an expansive clinker containing less than about 40% by weight of a stable calcium alumino sulfate compound, a cement clinker, and gypsum which are blended together after said expansive clinker and said cement clinker are separately ground to selected surface areas, said expansive clinker being ground to a surface area of from about 5000 to about 7500 sq. cm/gm and said cement clinker being ground to a surface area of from about 3000 to about 6200 sq. cm/gm, said expansive clinker comprising from about 4 to about 9% by weight of said cement, and said gypsum comprising from about 4 to about 10% by weight of said cement.
Claim 14
Dependent Claim
116 words
An improved expansive cement comprising a blend of an expansive clinker containing less than about 40% by weight of a stable calcium alumino sulfate compound, a cement clinker, and gypsum which are blended together after said expansive clinker and said cement clinker are separately ground to selected surface areas, said expansive clinker being ground to a surface area of from about 5000 to about 7500 sq. cm/gm and said cement clinker being ground to a surface area of from about 3000 to about 6200 sq. cm/gm, said expansive clinker comprising from about 4 to about 9% by weight of said cement, and said gypsum comprising from about 4 to about 10% by weight of said cement.
Claim 15
Independent Claim
69 words
A method of forming an improved expansive concrete containing a stable calcium alumino sulfate expansive clinker, Portland cement, gypsum, and water, the improvement comprising: grinding the expansive clinker in appropriate means separate from the grinding of the Portland cement to produce a controlled particle size without a substantial proportion of finer or coarser particles of expansive clinker and of a selected surface area greater than about 4600 sq. cm/gm.
Claim 16
Independent Claim
69 words
A method of forming an improved expansive concrete containing a stable calcium alumino sulfate expansive clinker, Portland cement, gypsum, and water, the improvement comprising: grinding the expansive clinker in appropriate means separate from the grinding of the Portland cement to produce a controlled particle size without a substantial proportion of finer or coarser particles of expansive clinker and of a selected surface area greater than about 4600 sq. cm/gm.
Claim 17
Dependent Claim
51 words
The method of claim 11 wherein the calcium alumino sulfate compound comprises less than 40% by weight of said expansive clinker and said expansive clinker comprises from about four to nine percent by weight of said Portland cement for forming a concrete that compensates for substantially all of the concrete shrinkage.
Claim 18
Dependent Claim
64 words
An improved expansive concrete containing a stable calcium alumino sulfate expansive clinker, Portland cement, gypsum, and water, the improvement comprising: the expansive clinker, before mixing with at least the Portland cement component of the concrete, having a controlled particle size without a substantial proportion of finer or coarser particles of expansive clinker and of a selected surface area greater than about 4600 sq. cm/gm.
Claim 19
Dependent Claim
64 words
An improved expansive concrete containing a stable calcium alumino sulfate expansive clinker, Portland cement, gypsum, and water, the improvement comprising: the expansive clinker, before mixing with at least the Portland cement component of the concrete, having a controlled particle size without a substantial proportion of finer or coarser particles of expansive clinker and of a selected surface area greater than about 4600 sq. cm/gm.
Claim 20
Dependent Claim
51 words
The improved expansive concrete of claim 13 wherein calcium alumino sulfate compound comprises less than about 40% by weight of said expansive clinker and said expansive clinker comprises from about 4% to 9% by weight of said Portland cement for forming a concrete that compensates for substantially all the concrete shrinkage.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-05 | 1987-06-06 | 1987-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-05 | 1991-06-06 | 1991-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-05 | 1995-06-06 | 1995-12-06 | $7700.00 | Window Closed / Lapsed |