The Model 4911 Rebar Strainmeter is designed for measuring strains in foundations, slurry walls, precast piles, caissons, bridge abutments, tunnel liners, etc. The standard Model 4911 (#4 rebar), known as the “Sister Bar,” is installed alongside structural rebar. Larger models (4911A) are available for welding directly into structural rebar. Where short-term dynamic measurements are to be made, bonded resistance (Model 3911/3911A) strain gages can be substituted, or added.
Specifications
| Standard Range | 3000 µε |
| Resolution | 0.4 µε |
| Accuracy¹ | ±0.25% F.S. |
| Nonlinearity | <0.5% F.S. |
| Temperature Range² | −20°C to +80°C |
| Rebar Sizes | 4911 | 4 (Sister Bar) 4911A | 6, 7, 8, 9, 10, 11, 12 |
| Active Gage Length | 914 mm |
¹Accuracy established under laboratory conditions.
²Other ranges available on request.




