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(A) Cement; 1. Specification for 33,43,53 Grade ordinary Portland cement IS 269 - 2015 2. Specification for Rapid hardening Portland cement IS 8041 - 1990 3. Specification for Portland Pozzolona cement IS 1489 (part 1&2) 1991 4. Methods of physical test for hydraulic cement IS 4031 - 1988 5. Method of chemical analysis of hydraulic cement IS ...
Mechanical evaluation of the pozzolanic activity is based upon a comparison of the compressive strength of mortar bars containing pozzolans as a partial replacement for Portland cement to reference mortar bars containing only Portland cement as binder. The mortar bars are prepared, cast, cured and tested following a detailed set of prescriptions.
The resulting hard substance, called 'clinker', is then ground with a small amount of gypsum (CaSO 4 ·2H 2 O) into a powder to make ordinary Portland cement, the most commonly used type of cement (often referred to as OPC). Portland cement is a basic ingredient of concrete, mortar, and most non-specialty grout. The most common use for Portland ...
Natural pozzolana (volcanic ash) deposits situated in Southern California in the United States. Pozzolans are a broad class of siliceous and aluminous materials which, in themselves, possess little or no cementitious value but which will, in finely divided form and in the presence of water, react chemically with calcium hydroxide (Ca(OH) 2) at ordinary temperature to form compounds possessing ...
Pozzolana from Mount Vesuvius volcano, Italy. Pozzolana or pozzuolana (/ ˌ p ɒ t s (w) ə ˈ l ɑː n ə / POT-s(w)ə-LAH-nə, Italian: [potts(w)oˈlaːna]), also known as pozzolanic ash (Latin: pulvis puteolanus), is a natural siliceous or siliceous-aluminous material which reacts with calcium hydroxide in the presence of water at room temperature (cf. pozzolanic reaction).
Portland cement is the most common type of cement in general use around the world as a basic ingredient of concrete, mortar, stucco, and non-specialty grout. It was developed from other types of hydraulic lime in England in the early 19th century by Joseph Aspdin , and is usually made from limestone .
Calcium silicate hydrate (also shown as C-S-H) is a result of the reaction between the silicate phases of Portland cement and water. This reaction typically is expressed as: 2 Ca 3 SiO 5 + 7 H 2 O → 3 CaO · 2 SiO 2 · 4 H 2 O + 3 Ca(OH) 2 + 173.6 kJ. also written in cement chemist notation, (CCN) as: 2 C 3 S + 7 H → C 3 S 2 H 4 + 3 CH + heat
Compared to using Portland cement, the resulting concrete-mix using EMC does not require a higher "total cementitious content" to meet strength-development requirements. In testing by BASF, the 28-day strength-development for 55% replacement of Portland cement by a natural pozzolanic EMC was 14,000 psi / 96.5 MPa (i.e. > C95). This comprised a ...