Concrete screw stair bolt W-BS/A4 with connecting thread
Concrete screw W-BS A4 type ST, stainless steel A4
ANC-(W-BS/ST)-A4-WS7-M10X30-40-8X105
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- Extremely flexible to use due to three anchoring depths
- Very high loads
- Smallest axial and edge clearance due to very low expansion effect
- Very fast and simple assembly, immediately load-bearing and easy to dismantle
- Pre-positioned, push-through or stand-off installation possible
- Attachment can be adjusted up to two times after assembly
European Technical Assessment ETA-16/0043 for fixing point, option 1, cracked and non-cracked concrete:
- Static and quasi-static effects (∅8 - ∅10)
- Seismic effect, performance category C1 (∅8 - ∅10)
- Fire resistance R30, R60, R90, R120
DIBt National technical approval/general type approval Z-21.1-2075 as bonded screw anchor for anchoring in concrete (∅10, type ST stair bolt)
- Use in combination with injectable mortar WIT-BS as bonded screw anchor WIT-BS
- In reinforced and non-reinforced and cracked and non-cracked concrete C20/25 to C50/60
Tensile capacity in concrete hollow body ceilings, (∅8 - ∅10) - expert report no. 21641 - 2016
From size 8, we recommend the use of a suitable tangential impact screwdriver for installation. The recommended nominal torque must be observed. When used outdoors, the drill hole can be sealed with WIT-BS injectable mortar.
Adjustment - subsequent aligning possible
Create the drill hole
Clean the drill hole
Place screw
Screw in the screw
Considered installed when the head is close fitting
Screw out the screw max. 2x each by max. 10 mm. Underlay. Screw in
Considered installed when the head is close fitting. Lining max. 10 mm. The required embedment depth must be maintained as a minimum
Locate the tensioning strand
Mark the tensioning strand and locate the next one
Mark the tensioning strands. Specify the drilling range
Create the drill hole. Observe spacing
Clean the drill hole
Screw in the screw
Considered installed when the head is close fitting. Observe the embedment depth/mirror thickness
European Technical Assessment ETA-16/0043 for fixing point, option 1, cracked and non-cracked concrete:
- Static and quasi-static effects (∅8 - ∅10)
- Seismic effect, performance category C1 (∅8 - ∅10)
- Fire resistance R30, R60, R90, R120
DIBt National technical approval/general type approval Z-21.1-2075 as bonded screw anchor for anchoring in concrete (∅10, type ST stair bolt)
- Use in combination with injectable mortar WIT-BS as bonded screw anchor WIT-BS
- In reinforced and non-reinforced and cracked and non-cracked concrete C20/25 to C50/60
Tensile capacity in concrete hollow body ceilings, (∅8 - ∅10) - expert report no. 21641 - 2016
Datasheets(X)
CAD data (available after login)
Fixing point:
Normal weight concrete C20/25 to C50/60 (cracked and non-cracked concrete)
Ideal for securing medium to heavy loads in concrete where disassembly of the attachment part is required:
- Securing e.g. stadium seats, barriers, railings, steel structures, supports and carriers, fence systems etc. in pre-positioned and push-through installation
- Fastenings under seismic conditions in earthquake areas
- Fastenings under exposure to fire
W-BS/A4 (A4 stainless steel) can be used in dry indoor conditions, outdoors (including in industrial atmospheres and coastal areas) or in wet rooms, provided that no particularly aggressive conditions are present.
For use in concrete < C20/25 and pressure-resistant natural stone (without approval)
Anchor size | 8 mm |
Anchor length (l) | 105 mm |
Connection thread | M10 |
Attachment height (t fix 1) | 40 mm |
Attachment height (t fix 2) | 30 mm |
Attachment height (t fix 3) | 20 mm |
Thread diameter | 10 mm |
Nominal drill-bit diameter (d 0) | 8.0 mm |
Drill hole depth (h 1.1) | 55 mm |
Drill hole depth (h 1.2) | 65 mm |
Drill hole depth (h 1.3) | 75 mm |
Embedding depth (h nom1) | 45 mm |
Embedding depth (h nom2) | 55 mm |
Embedding depth (h nom3) | 65 mm |
External drive | WS7 |
Material | Stainless steel A4 |
Surface | 0 - not applicable |
Through-hole in the component to be connected (d f) | 12.0 mm |
Head type | With connection thread (metric) |
Type description | W-BS A4 type ST |
| Anchor size [mm] | 8 | 10 | ||||||
| Nominal length of thread engagement | hnom [mm] | 45 | 55 | 65 | 55 | 75 | 85 | |
| Admissible centric tension load1) on an individual anchor without the influence of the edge distance | Tensile zone (cracked concrete C20/252), s ≥ 3 hef c ≥ 1.5 hef) | Nperm. [kN] = C20/252) | 2,4 | 4,3 | 5,7 | 4,3 | 8,0 | 9,6 |
| Compressive zone (non-cracked concrete C20/252), s ≥ 3 hef c ≥ 1.5 hef) | 3,6 | 5,7 | 7,6 | 5,7 | 9,5 | 11,9 | ||
| Admissible shear load1) on an individual anchor without the influence of the edge distance | Tensile zone (cracked concrete C20/252), c ≥ 10 hef) | Vperm. [kN] = C20/252) | 3,6 | 4,8 | 6,4 | 4,8 | 15,9 | 16,2 |
| Compressive zone (non-cracked concrete C20/252), c ≥ 10 hef) | 5,0 | 6,8 | 8,1 | 6,8 | 16,2 | 16,2 | ||
| 1) The partial safety factors of the resistances yM regulated in the approval/evaluation and a partial safety factor of the effects of γF = 1.4 have been taken into account. For a combination of tensile and shear loads, for the influence of the edge distance and anchor groups please see the appropriate guidelines e.g. DIN EN 1992-4. 2) The concrete has normal reinforcement. Higher values are possible for higher concrete strengths. | ||||||||
| Anchor size [mm] | 8 | 10 | |||||
| Nominal length of thread engagement | hnom [mm] | 45 | 55 | 65 | 55 | 75 | 85 |
| Minimum axis distance | smin [mm] | 40 | 50 | 50 | |||
| Axis distance | scr,N [mm] | 105 | 129 | 156 | 129 | 180 | 204 |
| Minimum edge distance | cmin [mm] | 40 | 50 | 50 | |||
| Edge distance | ccr,N [mm] | 52,5 | 64,5 | 78 | 64,5 | 90 | 102 |
| Minimum member thickness | hmin [mm] | 80 | 80 | 90 | 102 | ||
| Nominal drill diameter | d0 [mm] | 8 | 10 | ||||
| Diameter of cutting edges | dcut ≤ [mm] | 8,45 | 10,45 | ||||
| Drill hole depth | h1 ≥ [mm] | 55 | 65 | 75 | 65 | 85 | 95 |
| Through hole in the component being connected | df ≤ [mm] | 12 | 14 | ||||
| Width across flats | [mm] | WAF7 | WAF9 | ||||
| Connecting thread | [mm] | M10 x 30 | ∅10x140: M12 x 35 ∅10x160: M12 x 55 | ||||
| Max. rated torque of tangential impact screwdriver | Timp,max [Nm] | 300 | 400 | ||||
| Installation torque | Tinst ≤ [Nm] | 20 | 40 | ||||
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