ASTM C33/C33M-18 PDF Download

The ASTM C33/C33M-18 standard outlines the requirements for grading and quality of fine and coarse aggregate used in concrete. It specifies that fine aggregate may consist of natural sand, manufactured sand, or a combination thereof, and must be free of harmful organic impurities. Fine aggregate used in concrete subjected to wet conditions or contact with moist ground should not contain materials that react with the alkalis in cement, causing excessive expansion in the mortar or concrete. The specification also requires that fine aggregate pass the soundness test, which involves five cycles, and achieve a required weighted average loss.

Regarding coarse aggregate, it can consist of gravel, crushed gravel, crushed stone, air-cooled blast furnace slag, crushed hydraulic-cement concrete, or a combination thereof. Various sampling and test methods are outlined to determine the grading and fineness modulus, presence of organic impurities, effect of impurities on strength, soundness, clay lumps and friable particles, coal and lignite content, bulk density of slag, abrasion resistance, reactivity, freeze-thaw durability, and chert content.

The standard mentions that it can be used by contractors, concrete suppliers, and other purchasers to describe the material to be furnished. It provides guidance to ensure the quality of aggregates for most concrete applications, but acknowledges that more or less restrictive limits may be needed based on specific requirements or regional considerations. The specifier has the responsibility of selecting the proportions of fine and coarse aggregate and may include blending aggregate sizes if necessary or approved. Additionally, explanatory notes and footnotes in the standard provide further clarification but are not considered as requirements.