STANDARD
- MS-4 1989
OBJECTIVE
- To determine the swelling of the compacted specimen under specified conditions of the test.
APPARATUS
- Mould of height 127mm and inside diameter 101.6mm tripod of height 170mm suitable to fix for the mould of 101.6mm diameter.
- Dial gauge sensitivity to 0.025mm.
- Deep aluminum pan of size 194mmx 64mm
- Perforated bronze plate with an adjustable stem.
- Graduated scale capable of reading up to 1mm.
PROCEDURE
- Compact the asphalt mix into the mould as specified in MS-4 1989
- Allow the mould to cool at room temperature for at least one hour (This is done to permit rebound after compaction).
- Place the mould and the specimen in the aluminum pan.
- Place a perforated bronze disc on the top of the specimen.
- Position tripod on the mould with dial gauge reading 2.54mm.
- Introduce 500 ml of water into the mould and measure the distance (H) from top of the mould to the top of the water with a graduated scale and keep the set up undisturbed for 24 hours.
- After 24 hours again read dial gauge (R1) and record the change.
- Also, measure the distance (H1) from top of the mould to the top of the water with graduated scale and record the change as permeability or the amount of water in millimeters that percolate in to and / or through the test specimen.
CALCULATIONS
- Swelling, (%) = R1-R/ R
R = Initial dial gauge reading
R1 = Final dial gauge reading - Permeability = H- – H1
H = Initial height of the water from the top of the mould
H1 = Final height of the water from the top of the mould
REPORT
- Report the amount of swelling to the nearest second decimal and permeability to the nearest 1mm.
PRECAUTION
- Do not disturb the specimen during the period of swelling.