To test stone for transverse strength, specimen pieces are made in the form of blocks 200 × 50 × 50 mm.
Transverse Strength Test (IS: 1121 (Part II)):
To test stone for transverse strength, specimen pieces are made in the form of blocks 200 × 50 × 50 mm. These are tested in saturated and dry conditions similar to as explained in the compressive strength test. Test apparatus used for testing is shown in Fig. 1. Each specimen piece is supported upon two self-aligning bearers
A and B, 40 mm in diameter, the distance between centres of bearers being 150 mm. Bearer A is supported horizontally on two bearer screws C, which carry hardened steel balls D. Bearer B is supported on one such bearer screw and ball. The load is then applied centrally on the specimen piece at a uniform rate of 2 kN/min through a third bearer E, also 40 mm in diameter, placed midway between the supports upon the upper surface of the specimen S and parallel to the supports.
The average of the three results (separately for saturated and dry condition) should be taken for the purpose of determining transverse strength of sample. Any specimen giving result as much as 15 per cent below the average value should be examined for defects.
The transverse strength of the specimen is given by
R = 3WL/2bd3
where R = transverse strength in N/mm2
W = central breaking load in N
L = length of span in mm
b = average width in mm of the test piece at the mid section
d = average depth in mm of the test piece at the mid section