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US Patent 4350533 - High early strength cement
US Patent Issued on September 21, 1982
Estimated Patent Expiration Date:
August 3, 2001Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
Estimated Patent Expiration Date:
August 3, 2001Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.AbstractA rapid reaction of high alumina cement, gypsum, lime and water produces cementitious compositions in which the only significant factor contributing to strength during the very early stages of hydration (i.e., a few minutes to a few hours) is the formation of an amount of ettringite equal to from about 40% to about 60% of the weight the paste of water, the high alumina cement, the gypsum source, and the lime source. A substantially impermeable concrete having a 4-hour compressive strength of about 8000 p.s.i. may be produced from the cement powder of this invention. | InventorsAssigneeApplicationNo. 06/289589 filed on 08/03/1981US Classes:106/695With other cement material (e.g., Portland, calcium sulfate, etc.)ExaminersPrimary: Poer, JamesAttorney, Agent or FirmUS Patent References3775143, 3861929, 3922172, 4045237, Cementitious compositions having fast-setting properties and inhibited shrinkageIssued on: 08/30/1977 Inventor: Gaines , et al.4157263, Cementitious compositions having fast-setting properties and inhibited shrinkage Issued on: 06/05/1979 Inventor: Gaines , et al.4216022Well cementing in permafrost Issued on: 08/05/1980 Inventor: Wilson International ClassesC04B 7/32 (20060101)C04B 7/00 (20060101) |
