PROPERTIES OF AGGREGATES USED IN CONCRETE

14 IMPORTANT ENGINEERING PROPERTIES OF AGGREGATES USED IN CONCRETE

ENGINEERING PROPERTIES OF AGGREGATES

Aggregates are used in concrete to provide economy in the cost of concrete. Aggregates act as filler only. These do not react with cement and water.

SURFACE INDEX OF AGGREGATE

HOW TO BLEND AGGREGATE USING SURFACE INDEX VALUE?

Surface index of aggregates is another way to represent the specific surface of aggregate. This method was suggested by Murdock.  Murdock provided some empirical numbers to represent the specific surface of different aggregates grading (as shown in the table below).

HOW TO IDENTIFY & CLASSIFY SOIL ON SITE? [STEP-BY-STEP GUIDE]

ON-SITE IDENTIFICATION & CLASSIFICATION OF SOIL

The principle terms used by civil engineers to describe soils are

• Gravel (particle size larger than 4.75 mm)
• Sand (particle size within 4.75 mm to 0.075mm)
• Silt & Clay (particle size less than 0.075mm)

5 COMMON FIELD TESTS ON AGGREGATE TO CHECK ITS QUALITY

Aggregates influence the properties of concrete/mortar such as water requirement, cohesiveness and workability of the concrete in plastic stage, while they influence strength, density, durability, permeability, surface finish and colour in hardened stage.

FIELD TESTS FOR AGGREGATE

1. SURFACE MOISTURE CONTENT & ABSORPTION

The surface moisture in the aggregate, influences the water cement ratio, strength and durability of the mix. To determine the surface moisture of moist or wet aggregate, method is as follows-

Ductility Test of Bitumen