In breve
Post-installed rebar and large anchors are pull tested with a hydraulic hollow cylinder kit, not a 25 or 60 kN tester. The designer gives the test load; a hand pump drives a hollow ram around the bar, and a gauge reads the pressure, which is converted to load for that ram. A site test shows the bar held that load on the day; it doesn't check the design.
Questa guida spiega come vengono pianificate ed eseguite le prove in sito secondo la BS 8539:2012+A1:2021. Non sostituisce la norma, i dati del produttore dell'ancorante né le istruzioni del progettista o dell'ingegnere responsabile dell'intervento, che stabilisce il piano di prova, i carichi e i coefficienti. Una prova documenta quanto avvenuto in quel giorno; non approva un fissaggio per l'uso.
Key figures
| 18 t kit | 176 kN, 51 mm stroke, 25.1 cm² piston area |
|---|---|
| 36 t kit | 358 kN, 51 mm stroke, 51.2 cm² piston area |
| Rated pressure | 700 bar |
| Rebar adaptors | R6, R8, R10, R12, R14, R16, R20, R22, R25 and R32 |
| Gauge | Staht G1 Pro, to 1000 bar, UKAS traceable, 0.25% of full scale |
What is post-installed rebar?
A straight deformed reinforcing bar set in mortar in a hole drilled in hardened concrete, to connect new concrete to old. EOTA's assessment document for these systems is EAD 330087-01-0601, which covers connections designed to EN 1992-1-1 and EN 1992-1-2 and also post-installed rebar used as tension anchors. A system's European Technical Assessment gives its performance and how it's installed.
What can a site pull test show?
- It checks tension only. Where a connection also carries shear, the engineer decides whether the test load needs raising.
- A proof test checks the installation, not whether the design is right.
- Site tests show performance only in uncracked concrete.
- Bonded bars and anchors are tested only after at least the maker's recommended curing time.
The designer or engineer responsible sets the load and the number to test.
What about holding-down bolts?
Cast-in bolts are among the anchors not usually site tested. A holding-down bolt that is post-installed is a large anchor, tested as the designer specifies. Staht's heavy duty kits are for testing larger fixings and rebar; tell us the bolt's thread and test load and we'll say how it connects to the cylinder.
Which heavy duty kit?
| Kit | Capacity | Cylinder | Kit weight |
|---|---|---|---|
| [18 t kit, 800-000](/products/hd-tester-kit-18t-in-case) | 176 kN | 51 mm stroke; 25.1 cm² piston; 26 mm bore; 171 mm tall | 17.9 kg |
| [36 t kit, 800-001](/products/hd-tester-kit-36t-in-case) | 358 kN | 51 mm stroke; 51.2 cm² piston; 39 mm bore; 261 mm tall | 26.7 kg |
| [18 and 36 t kit, 800-004](/products/hd-tester-kit-18t-36t-in-case) | Both cylinders | As above | 29.7 kg |
What else is in each kit?
A two-stage aluminium hand pump rated to 700 bar, a 3 m high-pressure hose with quick connectors, the G1 Pro digital Bluetooth gauge and a wheeled Peli case with a foam insert. Rebar adaptors grip the bar and are bought separately.
How is pressure turned into load?
Load is pressure times the piston area. At its rated 700 bar (70 N/mm²) the 18 t cylinder's 25.1 cm² (2,510 mm²) gives 175.7 kN, and the 36 t cylinder's 51.2 cm² (5,120 mm²) gives 358.4 kN. The G1 Pro links to the Staht app, where cylinder sizes can be programmed and saved.
Worked example: a 100 kN test
The designer asks for 100 kN on a post-installed bar.
- 18 t cylinder: 100,000 N ÷ 2,510 mm² = 39.8 N/mm², about 398 bar.
- 36 t cylinder: 100,000 N ÷ 5,120 mm² = 19.5 N/mm², about 195 bar.
Both are within the 700 bar rating. Pick the cylinder whose bore the bar or its adaptor fits, and whose stroke is longer than the movement you expect.
Staying safe at high loads
- The cylinder's stroke, 51 mm, must be longer than the movement expected.
- Every part that carries load must be strong enough with a margin: high-strength rods, nuts of a suitable grade, and rods checked before each test.
- Secure the rig on walls and soffits.
- Our advice: keep everyone out of line with the bar while it's loaded.
What should the record show?
Everything an anchor test report records, plus the cylinder used and its piston area, and the pressure read as well as the load. See what a test report should record, or use our anchor test report template.
Related pages
More questions
Not with the rebar adaptors, which are for the heavy duty kits. A t60 reaches 60 kN on threaded anchors and eyebolts.
Only if the designer asks for it. A proof test stops at the test load and the bar stays in use; tests to failure are done on bars installed for the test.
The 36 t kit: it reaches 358 kN, where the 18 t kit stops at 176 kN.
The designer or the engineer responsible for the connection.
Fonti
- EAD 330087-01-0601 Systems for post-installed rebar connections with mortar, EOTA
- BS 8539:2012+A1:2021 Code of practice for the selection and installation of post-installed anchors in concrete and masonry, BSI
- Staht Heavy Duty Test Kit brochure, Staht
- Staht Heavy Duty Test Kits, Technical Datasheets No 170, 171 and 172, Staht
- Staht 18 t and 36 t cylinders, Technical Datasheets No 186 and 187, Staht
- Staht Rebar Adaptors R6 to R32, Technical Datasheets No 173 to 182 (R32 also in the Heavy Duty Test Kit brochure), Staht
- Anchor Pull Test Report: What It Should Record, Staht
Test rebar and large anchors
Heavy duty kits to 176 kN and 358 kN, with the G1 Pro gauge.