| S.No. | Checkpoint | IS Requirement | Status |
|---|---|---|---|
| A. SAMPLE PREPARATION | |||
| A1 | Representative bricks selected; minimum 5 bricks tested per batch Acceptance: Random selection; quality range verified; measurements taken | Cl. 3 — Sampling | OK NC NA HOLD |
| A2 | Brick surfaces prepared: bedded in 10-12 mm cement mortar on compression plates Acceptance: Mortar 1:3 cement:sand; surfaces level; cured 24 hours before testing | Cl. 4.1 — Specimen preparation | OK NC NA HOLD |
| B. COMPRESSION TESTING | |||
| B1 | Testing machine calibrated per ASTM/ISO standards; accuracy ±1% Acceptance: Machine certified; load rate 14±2 N/mm²/min; centered loading | Cl. 5 — Equipment | OK NC NA HOLD |
| B2 | Load applied uniformly until brick fails; failure load recorded in kN Acceptance: Constant rate; no shock; failure point noted; load measured to 0.1 kN | Cl. 5.1 — Loading procedure | OK NC NA HOLD |
| C. STRENGTH CALCULATION & RESULTS | |||
| C1 | Compressive strength calculated: Strength (N/mm²) = Ultimate Load (N) / Bearing Area (mm²) Acceptance: Strength in MPa; average of 5 bricks; standard deviation calculated | Cl. 6 — Calculation | OK NC NA HOLD |
| C2 | Results compared with IS 1077 classification (Class A: min 15 MPa, Class B: min 10 MPa) Acceptance: Class A: ≥15 MPa; Class B: ≥10 MPa; results meet specification | Cl. 6.1 — Classification | OK NC NA HOLD |