US4040855A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of lightweight concrete
Assignee: Individual
•
Filing: 1975-08-04
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Granted: 1977-08-09
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Expires: 1995-08-04
Abstract
Abstract By using as the lightweight aggregate, in the manufacture of lightweight concrete, polystyrene-bead materials of particularly controlled characteristics in regard to bead size and coefficient of variation of absolute volume, there is obtained a substantial improvement in regard to the accuracy with which the density of the product lightweight concrete can be controlled or preordained. Since the strength and insulation-value properties are closely related to the density, the improvement aids in the design and production of more economical parts.
Inventors
- 👤 Arthur A. Rady-Pentek
- 👤 Edwin William Fairweather
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:28
CPC Classifications
C; C04; C04B; C04B16/00; C04B16/04; C04B16/08; Y; Y10; Y10S; Y10S264/00; Y10S264/07
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
237 words
The method of making lightweight concrete having a density of 0.340 to 1.060 grams per cubic centimeter which comprises mixing with cement, water, water-reducing admixture and air-entraining agent an aggregate material consisting essentially of a mixture of first and second portions of particles of polystyrene expanded to a density of 0.013 to 0.019 grams per cubic centimeter, said particles being of controlled size such that said first portion thereof consists of beads which in their unexpanded form are substantially all of a diameter between 1.04 and 0.35 millimeters and 90 percent by weight of a diameter between 0.9 and 0.4 millimeters, and said second portion thereof consists of beads which in their unexpanded form are substantially all of a diameter between 1.29 and 0.35 millimeters and 90 percent by weight of a diameter between 1.24 and 0.58 millimeters, said portions being admixed in a weight ratio of 2.5 to 3.5 parts by weight of said second portion per one part by weight of said first portion, the mixture of particles being of such uniformity that ten samples each of approximately 1200 to 1500 cubic centimeters in volume of loose and dry expanded beads exhibit a co-efficient of variation C V in respect to absolute-volume factor of under 3.0, said aggregate being mixed with water, cement, water-reducing admixture, air-entraining agent and optionally sand to form said lightweight concrete under conditions such that bead-to-bead contact is substantially wholly avoided.
Claim 2
Independent Claim
237 words
The method of making lightweight concrete having a density of 0.340 to 1.060 grams per cubic centimeter which comprises mixing with cement, water, water-reducing admixture and air-entraining agent an aggregate material consisting essentially of a mixture of first and second portions of particles of polystyrene expanded to a density of 0.013 to 0.019 grams per cubic centimeter, said particles being of controlled size such that said first portion thereof consists of beads which in their unexpanded form are substantially all of a diameter between 1.04 and 0.35 millimeters and 90 percent by weight of a diameter between 0.9 and 0.4 millimeters, and said second portion thereof consists of beads which in their unexpanded form are substantially all of a diameter between 1.29 and 0.35 millimeters and 90 percent by weight of a diameter between 1.24 and 0.58 millimeters, said portions being admixed in a weight ratio of 2.5 to 3.5 parts by weight of said second portion per one part by weight of said first portion, the mixture of particles being of such uniformity that ten samples each of approximately 1200 to 1500 cubic centimeters in volume of loose and dry expanded beads exhibit a co-efficient of variation C V in respect to absolute-volume factor of under 3.0, said aggregate being mixed with water, cement, water-reducing admixture, air-entraining agent and optionally sand to form said lightweight concrete under conditions such that bead-to-bead contact is substantially wholly avoided.
Claim 3
Dependent Claim
53 words
A method as defined in claim 1, characterized in that said aggregate material is mixed with cement, water-reducing admixture and air-entraining agent, sand in an amount of up to approximately equal to the weight of the cement, and water in an amount of 0.39 to 0.50 parts by weight per part of cement.
Claim 4
Dependent Claim
11 words
A lightweight concrete made according to the method of claim 2.
Claim 5
Dependent Claim
17 words
A method as defined in claim 1, said coefficient of variation C V being 1.9 to 2.3.
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) | 1980-08-08 | 1981-02-07 | 1981-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-08 | 1985-02-07 | 1985-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-08 | 1989-02-07 | 1989-08-09 | $7700.00 | Window Closed / Lapsed |