Anchor Screws

Recommended Loads for a Single Anchor Installation

    All data in this section applies to:

  • Correct setting (see setting instructions)
  • Minimum base material thickness
  • No edge distance and spacing influence
  • Concrete C32/40, fck, cube = 32N/mm2
Anchor Type M12
Un-cracked concrete
1st embedment depth
Recommended shear load (imfluence of concrete) VRec [kN] 15
Recommended shear load (pure shear load) Vrec,s [kN] 23,8
2nd embedment depth
Recommended shear load (imfluence of concrete) VRec [kN] 23,8
Recommended shear load (pure shear load) Vrec,s [kN] 23,8
3rd embedment depth
Recommended shear load (imfluence of concrete) VRec [kN] 23,8
Recommended shear load (pure shear load) Vrec,s [kN] 23,8
Anchor Type M12
Cracked concrete
1st embedment depth
Recommended shear load (imfluence of concrete) VRec [kN] 10,7
Recommended shear load (pure shear load) Vrec,s [kN] 23,8
2nd embedment depth
Recommended shear load (imfluence of concrete) VRec [kN] 17,1
Recommended shear load (pure shear load) Vrec,s [kN] 23,8
3rd embedment depth
Recommended shear load (imfluence of concrete) VRec [kN] 23,8
Recommended shear load (pure shear load) Vrec,s [kN] 23,8

Tension Example Installation

Tension Example Installation
Tension Example Installation

Shear Example Installation

Shear Example Installation
Shear Example Installation

Installation Data

scaffSAFE M12
Drill hole diameter d0 [mm] Ø12
Nominal embedment depth hnom [mm] 60 80 100
Min hole depth h0 [mm] 70 90 110
Max installation torque Tinst [Nm] 1000*
Min thickness of concrete member hmin [mm] 110 130 155
Min spacing Smin [mm] 80 80 80
Min edge distance Cmin [mm] 80 80 80
Effective embedment depth hef [mm] 46 63 80
Threaded outer diameter dth [mm] 14,90
Characteristic resistance under tension load (steel failure) NRk,s [kN] 83.1
Characteristic tension - steel failure V0Rk,s [kN] 41.6
Characteristic resistance (pull-out failure) cracked concrete NRk,p [kN] 15,40 24,60 35,20
Characteristic resistance (pull-out failure) uncracked concrete NRk,p [kN] 15,40 24,60 35,20
Installation Data

* The screw tightening torque depends on the type of concrete, depending on whether it is C20/25-C50/60 class concrete, the type of aggregate, the type of drilling, and the drill used. The tightening torque of 1000Nm cannot be exceeded.

Tie Pattern Recommendation

The below data details the maximum distance between ties for each region.

Region A Region B Region C Region D
Wind Speed (km/hr) 148 173 212 263
Wind Preassure (kPa) 1.12 1.52 2.32 3.53
Sheeted area between ties [Ta] (m2) 11.5 8.5 5.5 3.6
Sheeted vertical distance between ties [y] (m) 3.0 3.0 3.0 3.0
Sheeted horizontal distance between ties [x] (m) 4.8 2.4 1.8 1.2
Unsheeted area between ties [Ta] (m2) 32.1 23.7 15.5 10.2
Unsheeted vertical distance between ties [y] (m) 3 3 3 3
Unsheeted horizontal distance between ties [x] (m) 7.2 7.2 4.8 2.4

NOTE:

  • Wind loads based on 15m scaffold height, TC2, temporary works recurrence interval 1/100. Design wind pressure varies between 0.92kPa to 2.64kPa. (Design wind speeds 134km/hr to 213km/hr). Drag= 1.2 (cladded). Solidity Ratio = 30%.
  • Horizontal single leg ties are rated to 9kN ULT (conventional couplers) or 12kN ULT (Layher couplers). Note that check couplers must be used inside and out of coupling to the standard. Consider the applied be load to the building structure is 12.0kN
  • All information if given is indicative and for information only. Please refer to AS1170.2:2011 Structural design actions - Wind actions or consult with a temporary works engineer if you are in doubt of any information relating to the tie details above.
Tie pattern recommendation
  • Region A Normal
  • Region B Intermediate
  • Region C Tropical Cyclones
  • Region D Severe Tropical Cyclones

DistanceThe distance between ties (X) assumes a vertical tie spacing of 3m (Y). Please consider this value and change as required.

Design Process for Single Anchors in Non Cracked Concrete

STEP 1:TENSION LOADING

The design tensile resistance is the lower of: Concrete cone or concrete splitting resistance. whichever governing NRd = fB • N*Rd.c

tension1
tension2
tension3
tension4
Anchor Type M12
Un-cracked concrete
1st embedment depth
Design tension load NRd NRd 8,8
2nd embedment depth
Design tension load NRd [kN] 16,8
3rd embedment depth
Design tension load NRd [kN] 24,1
Anchor Type M12
Cracked concrete
1st embedment depth
Design tension load NRd [kN] 6,2
2nd embedment depth
Design tension load NRd [kN] 12
3rd embedment depth
Design tension load NRd [kN] 17,2

N*Rd.c is obtained from the relevant design tables

fB influence of concrete strength

Concrete Strengths f'c,cyl (MPa) 20 25 32 40 50
fB 0.79 0.87 1 1.11 1.22

Design steel resistance (tension) NRd.s

Anchor Type M12 M16
NRd,s [kN] 30.3 56.5

STEP 2:SHEAR LOADING

The design shear resistance VRd is the lower of: Design concrete edge resistance VRd,c = fB • V*Rd,c

Share1
Share2
Share3

fB influence of concrete strength

Concrete Strengths f'c,cyl (MPa) 20 25 32 40 50
fB 0.79 0.87 1 1.11 1.22

Design steel resistance (shear) VRd,s

Anchor Type M12
Un-cracked concrete
1st embedment depth
Design shear load (Influence of concrete) VRd [kN] 21
Design shear load (pure shear load) VRd,s [kN] 33,2
2nd embedment depth
Design shear load (Influence of concrete) VRd [kN] 33,3
Design shear load (pure shear load) VRd,s [kN] 33,3
3rd embedment depth
Design shear load (Influence of concrete) VRd [kN] 33,3
Design shear load (pure shear load) VRd,s [kN] 33,3
Anchor Type M12
Cracked concrete
1st embedment depth
Design shear load (Influence of concrete) VRd [kN] 10,7
Design shear load (pure shear load) VRd,s [kN] 23,8
2nd embedment depth
Design shear load (Influence of concrete) VRd [kN] 17,1
Design shear load (pure shear load) VRd,s [kN] 23,8
3rd embedment depth
Design shear load (Influence of concrete) VRd [kN] 33,3
Design shear load (pure shear load) VRd,s [kN] 33,3

V*Rd,c is obtained from the relevant design tables

STEP 3:COMBINE TENSION AND SHEAR LOADING

Calculation

The following equations must be satisfied: NSd/NRd + VSd/VRd ≤ 1.2 and NSd/NRd ≤ 1, VSd/VRd ≤ 1

Static and Quasi-Static Resistance (For a Single Anchor)

    All data in this section applies to:

  • Correct setting (see setting instructions)
  • Minimum base material thickness
  • No edge distance and spacing influence
  • Concrete C20/25, fck, cube = 25N/mm2

DESIGN RESISTANCE

Anchor Type M12
Un-cracked concrete
1st embedment depth
Design tension load NRd [kN] 8,8
Design shear load (Influence of concrete) VRd [kN] 21
Design shear load (pure shear load) VRd,s [kN] 33,2
2nd embedment depth
Design tension load NRec [kN] 16,8
Design shear load (Influence of concrete) VRd [kN] 33,3
Design shear load (pure shear load) VRd,s [kN] 33,3
3rd embedment depth
Design tension load NRec [kN] 24,1
Design shear load (Influence of concrete) VRd [kN] 33,3
Design shear load (pure shear load) VRd,s [kN] 33,3
Anchor Type M12
Cracked concrete
1st embedment depth
Design tension load NRd [kN] 6,2
Design shear load (Influence of concrete) VRd [kN] 10,7
Design shear load (pure shear load) VRd,s [kN] 23,8
2nd embedment depth
Design tension load NRec [kN] 12
Design shear load (Influence of concrete) VRd [kN] 24
Design shear load (pure shear load) VRd,s [kN] 33,3
3rd embedment depth
Design tension load NRec [kN] 17,2
Design shear load (Influence of concrete) VRd [kN] 33,3
Design shear load (pure shear load) VRd,s [kN] 33,3

RECOMMENDED RESISTANCE

Anchor Type M12
Un-cracked concrete
1st embedment depth
Recommended tension load NRec [kN] 6,3
Recommended shear load (imfluence of concrete) VRec [kN] 15
Recommended shear load (pure shear load) Vrec,s [kN] 23,8
2nd embedment depth
Recommended tension load NRec [kN] 12
Recommended shear load (imfluence of concrete) VRec [kN] 23,8
Recommended shear load (pure shear load) Vrec,s [kN] 23,8
3rd embedment depth
Recommended tension load NRec [kN] 17,2
Recommended shear load (imfluence of concrete) VRec [kN] 23,8
Recommended shear load (pure shear load) Vrec,s [kN] 23,8
Anchor Type M12
Cracked concrete
1st embedment depth
Recommended tension load NRec [kN] 4,5
Recommended shear load (imfluence of concrete) VRec [kN] 10,7
Recommended shear load (pure shear load) Vrec,s [kN] 23,8
2nd embedment depth
Recommended tension load NRec [kN] 8,3
Recommended shear load (imfluence of concrete) VRec [kN] 17,1
Recommended shear load (pure shear load) Vrec,s [kN] 23,8
3rd embedment depth
Recommended tension load NRec [kN] 12,3
Recommended shear load (imfluence of concrete) VRec [kN] 23,8
Recommended shear load (pure shear load) Vrec,s [kN] 23,8

CHARACTERISTIC LOADS

Anchor Type M12
Un-cracked concrete
1st embedment depth
Characteristic tension load NRk [kN] 15,8
Characteristic shear load (Influence of concrete) VRk [kN] 31,5
Characteristic shear load (pure shear load) VRk,s [kN] 41,6
2nd embedment depth
Characteristic tension load NRec [kN] 25,3
Characteristic shear load VRec [kN] 41,6
Characteristic shear load (pure sher load) VRk,s [kN] 41,6
3rd embedment depth
Characteristic tension load NRec [kN] 36,1
Characteristic shear load VRec [kN] 41,6
Characteristic shear load (pure sher load) VRk,s [kN] 41,6
Anchor Type M12
Cracked concrete
1st embedment depth
Characteristic tension load NRec [kN] 11,2
Characteristic shear load (Influence of concrete) VRec [kN] 22,5
Characteristic shear load (pure shear load) VRk,s [kN] 41,6
2nd embedment depth
Characteristic tension load NRec [kN] 18
Characteristic shear load VRec [kN] 36
Characteristic shear load (pure sher load) VRk,s [kN] 41,6
3rd embedment depth
Characteristic tension load NRec [kN] 25,8
Characteristic shear load VRec [kN] 41,6
Characteristic shear load (pure sher load) VRk,s [kN] 41,6

scaffSAFE Products

Learn More

Let's Talk

Send Enquiry For scaffSAFE

Call Us
0418 484 443
Write an email to us
Email Us
Note: Fields marked with (*) are mandatory.