| S.No. | Checkpoint | IS Requirement | Status |
|---|---|---|---|
| A. TEST SETUP & EQUIPMENT DETAILS | |||
| A1 | Rebound Hammer Make & Model Acceptance: Portable rebound hammer (e.g., Proceq L or N type) | Identification of rebound hammer device used | OK NC NA HOLD |
| A2 | Hammer Type (N or L) Acceptance: Type N: standard (0.225 Nm impact energy) | Type L: light (0.075 Nm) for weak concrete | Specification of hammer energy type | OK NC NA HOLD |
| A3 | Calibration Status Acceptance: Calibration current, dated within last 6-12 months | Verification of hammer calibration validity | OK NC NA HOLD |
| A4 | Anvil Calibration Reading Acceptance: Rebound number within manufacturer's range (typically 80-100 for new anvil) | Test hammer on anvil before use | OK NC NA HOLD |
| A5 | Expected Anvil Reading Range Acceptance: Per manufacturer specification (e.g., Type N: 80-102) | Documented acceptable anvil range for this hammer | OK NC NA HOLD |
| A6 | Surface Preparation Acceptance: Ground smooth (grinding preferred), dry, free of coatings/paint/dust | Preparation of test surface | OK NC NA HOLD |
| A7 | Test Surface Condition Acceptance: Clean, flat, firm, no loose concrete or aggregate exposure | Document actual surface state before testing | OK NC NA HOLD |
| A8 | Surface Moisture Content Acceptance: Dry preferred; wet surface requires correction factor (+5-10 rebound points) | Assessment of surface moisture/saturation | OK NC NA HOLD |
| B. TEST METHODOLOGY & ORIENTATION | |||
| B1 | Test Orientation Acceptance: Horizontal | Vertical Up | Vertical Down (orientation affects reading; correction factors apply) | Direction in which hammer impacts (horizontal/vertical) | OK NC NA HOLD |
| B2 | Orientation Correction Factor Acceptance: Horizontal: 0 | Vertical Up: -3 to -4 | Vertical Down: +3 to +4 (add to reading) | Applied correction for non-horizontal orientation | OK NC NA HOLD |
| B3 | Number of Test Points Acceptance: Minimum 3 test locations recommended; typically 9 readings per location (3x3 grid) | Total locations tested on element | OK NC NA HOLD |
| B4 | Test Point Spacing Acceptance: Minimum 25 mm between impact points (avoid rebound influence) | Distance between test locations | OK NC NA HOLD |
| B5 | Distance from Element Edges Acceptance: Minimum 20 mm from edges (avoid edge effects) | Clearance from edges, corners, reinforcement | OK NC NA HOLD |
| B6 | Reinforcement Avoidance Acceptance: Rebar causes high readings; locate and mark reinforcement | Ensure test points avoid steel reinforcement | OK NC NA HOLD |
| C. TEST RESULTS TABLE (Per Location) | |||
| C1 | Location ID Acceptance: e.g., L1, L2, L3 or grid coordinates (mark on sketch) | Unique identification for each test location | OK NC NA HOLD |
| C2 | Test Surface Orientation Acceptance: Horizontal | Vertical Up | Vertical Down | Direction of hammer impact at this location | OK NC NA HOLD |
| C3 | 12 Individual Rebound Readings Acceptance: Record all 12 values; identify and note any obvious outliers | Raw rebound numbers from 12 impacts at location | OK NC NA HOLD |
| C4 | Outlier Identification & Removal Acceptance: Remove largest and smallest if >6 points from median; keep remaining 10 | Discard readings more than 6 points from median | OK NC NA HOLD |
| C5 | Average Rebound Number (Corrected) Acceptance: Final rebound number used for strength estimation | Mean of valid readings after outlier removal and orientation correction | OK NC NA HOLD |
| C6 | Estimated Compressive Strength (MPa) Acceptance: Use manufacturer's correlation curve or site-specific calibration | Convert rebound number to strength using calibration curve | OK NC NA HOLD |