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Abrams' law (also called Abrams' water-cement ratio law) [1] is a concept in civil engineering. The law states the strength of a concrete mix is inversely related to the mass ratio of water to cement. [1] [2] As the water content increases, the strength of concrete decreases. Abrams’ law is a special case of a general rule formulated ...
A w/c ratio higher than 0.60 is not acceptable as fresh concrete becomes "soup" [2] and leads to a higher porosity and to very poor quality hardened concrete as publicly stated by Prof. Gustave Magnel (1889-1955, Ghent University, Belgium) during an official address to American building contractors at the occasion of one of his visits in the ...
The lime putty, when mixed at a 1:3 ratio, fills these voids to create a compact mortar. Analysis of mortar samples from historic buildings typically indicates a higher ratio of around 1 part lime putty to 1.5 part [18] aggregate/sand was commonly used. This equates to approximately 1 part dry quicklime to 3 parts sand.
In a comprehensive research program, Abrams established the relationship between the water–cement ratio and the compressive strength of concrete. The results were first published in 1918 in D. A. Abrams, Design of Concrete Mixtures, Bulletin 1, Structural Materials Research Laboratory, Lewis Institute, Chicago, 1918.
Vitruvius specifies a ratio of 1 part lime to 3 parts pozzolana for mortar used in buildings and a 1:2 ratio for underwater work. [10] [11] The Romans first used hydraulic concrete in coastal underwater structures, probably in the harbours around Baiae before the end of the 2nd century BC. [12]
51% (C 3 S), 24% (C 2 S), 6% (C 3 A), 11% (C 4 AF), 2.9% MgO, 2.5% (SO 3), 0.8% ignition loss, and 1.0% free CaO. A limitation on the composition is that the (C 3 A) shall not exceed 8%, which reduces its vulnerability to sulphates. This type is for general construction exposed to moderate sulphate attack, and is meant for use when concrete is ...
The active ingredients are monocalcium aluminate CaAl 2 O 4 (CaO · Al 2 O 3 or CA in cement chemist notation, CCN) and mayenite Ca 12 Al 14 O 33 (12 CaO · 7 Al 2 O 3, or C 12 A 7 in CCN). Strength forms by hydration to calcium aluminate hydrates. They are well-adapted for use in refractory (high-temperature resistant) concretes, e.g., for ...
The parts are in terms of weight – not volume. For example, 1-cubic-foot (0.028 m 3) of concrete would be made using 22 lb (10.0 kg) cement, 10 lb (4.5 kg) water, 41 lb (19 kg) dry sand, 70 lb (32 kg) dry stone (1/2" to 3/4" stone). This would make 1-cubic-foot (0.028 m 3) of concrete and would weigh about 143 lb (65 kg). The sand should be ...