Excessively coarse material will produce harsh mixes that are more difficult to place, consolidate, and finish.Table 1 - Fineness modulus (FM) is calculated by totaling the percentFine aggregate should fall within gradation limits provided in ASTM C 33, Section 6.

As far as shape is concerned, rounded shape aggregate provides economical mix design for normal strength concrete.However, angular coarse aggregate is Changes in gradation, maximum size, unit weight, and moisture content can all alter the character and performance of your concrete mix.Economy is another reason for thoughtful aggregate selection. desired in the case of high strength concrete. The clear cover or minimum distance between the reinforcement bars. CONSTRUCTION SITES WERE LOCATED IN DESERT AREAS (NORTH AFRICA AND ARABIAN GULF) WHERE DUE TO THE SPECIAL CONDITIONS ELIMINATION OF COARSE AGGREGATE HELPED EXPEDITE CONSTRUCTION WHILE RESULTING IN ECONOMY. concrete without coarse aggregate. 0000004013 00000 n When the aggregate is sieved through 4.75mm sieve, the aggregate retained is called coarse aggregate. But a closer look reveals the major role and influence aggregate plays in the properties of both fresh and hardened concrete. Fig. 5-5. 64 0 obj << /Linearized 1 /O 66 /H [ 782 353 ] /L 144421 /E 7226 /N 10 /T 143023 >> endobj xref 64 16 0000000016 00000 n

The proportions between coarse and fine aggregates will change based on the unique characteristics of each aggregate, the placement method, and the finish desired.The dividing line between fine and coarse aggregate is the 3/8-inch sieve.

0000002232 00000 n concrete without coarse aggregate. two cases where coarse aggregate was eliminated from concrete and sand-cement-mortar was used for construction are described. construction sites were located in desert areas (north africa and arabian gulf) where due to the special conditions elimination of coarse aggregate helped expedite construction while resulting in economy. (Photo courtesy of PCA)Photo 6 - Maximum aggregate size based on placement method and slab thickness. The IS limits for above tests are Aggregate absorption is used for applying a correction factor for aggregates in dry condition and determining water demand for concrete in saturated surface dry condition.

0000002788 00000 n demand to achieve certain workability. 0000000667 00000 n Aggregates are generally thought of as inert filler within a concrete mix. Its properties such as strength, maximum size, shape, and water absorption influence water demand, the quantity of cement and fine aggregate in concrete mixture. to coat particles and maintain cohesiveness of concrete mix. to lower the cement consumption.Maximum To produce good quality, durable concrete containing a portion of recycled concrete aggregate often requires trial concrete mixes and close monitoring of the properties of the old recycled concrete, with mix adjustments made, as needed.Both gravel and crushed stone produce quality concrete. Some chert particles are more absorptive than higher-quality aggregates. 1:4-1:6 for plastering and brick work. The allowable percentage of deleterious substances for both fine and coarse aggregate are listed in ASTM C 33 Tables 1 and 3, respectively. The FM for fine aggregate should fall within the range of 2.3 to 3.1.

This provides an estimate of how the blend will perform in concrete. grading of coarse aggregate is important to get cohesive and dense concrete. 0000001429 00000 n Fine Aggregate vs Coarse Aggregate . These properties make rounded aggregate to yield the most economical mixes for concrete grades up to M35. water requirements, workability, pumpability, and durability of concrete.