Technical handbook Panel Anchoring System

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2 Basic principles of sandwich panels 3 Design conditions 4 Basic placement of anchors and pins 9 Large elements (muliple rows) 10 Small elements (two rows) 10 Turned elements 10 Slender elements 10 Cantilevering elements 10 Load bearing anchors 10 Narrow transitions over and below openings, i.e. doors and windows 10 Extending panel around corner 10 2

3 Basic principles of sandwich panels A sandwich panel is a concrete element composed of three different layers, one load bearing wall, one layer of insulation and one suspended panel. The purpose with the Panel Anchoring system is to ensure the performance of the wall by carrying the weight of the suspended panel as by temperature movements, shrinkage, mould suction etc. The suspended panel (usually the façade panel) is exposed by larger temperature differences over time compared to the load bearing wall (usually placed internally) which have a more even temperature condition (indoor climate). This result in that the suspended panel varies in size to a greater extent compared to the load bearing panel. The anchoring system is designed to ensure that the movements due to the temperature difference do not cause problems such as cracks, curving of the wall etc. The temperature movements are taken care of by a proper placement of the load bearing anchors and the restraint ties, and by aiming for an as low friction as possible between the insulation and the concrete. 3

4 Design conditions Governing documents: EC1, EC2, EC3, CEN/TS-1992, Swedish national parameters Min. quality of concrete C30/37 Min. concrete strength when demoulding 16 MPa The anchoring system is designed for a wind load according to v b = 26 m/s, terrain type II-IV, height up to 30 m, shape factor suction 1,2 shape factor pressure 0,8 Adhesion force: Well-greased steel form 1 kn/m 2, smooth wooden form 2 kn/m 2, unplanned wooden form 3 kn/m 2, If other conditions please contact us Restraint ties are not allowed to be placed sparser than cc 1200 mm Max. element length/height 7,5 m Min. thickness of the load bearing wall 90 mm, 80 mm is acceptable if you use hard insulation Thickness of the suspended panel mm Min. reinforcement in suspended panel is grid 5150 NP500AB-W Min. reinforcement In the load bearing wall is grid 5300 NP500AB-W 4

5 Function: NEO-BA2 has the task to transfer the vertical load (Qv), which arises from to the self weight of the suspended panel, to the load bearing wall. Material: Stainless steel A2 and A4 Reinforcement: Mounting bar K500B-T, grid NP500AB-W NEO-BA2 can be found in following dimensions: NEO-BA2-6: mm, NEO-BA2-8: mm, NEO-BA2-10: mm Measurments NEO-BA2 [mm] NEO-BA2-6 NEO-BA2-8 NEO-BA2-10 Ø I a min. 50 min. 50 min. 50 c min. 55 min. 55 min. 55 H a + b + c a + b + c a + b + c U min. 60 min. 60 min. 60 B min. 90 min. 90 min. 90 h min. 25 min. 25 min. 25 Mounting bar K500B-T r 2 Ø8 x Ø8 x Ø8 x 700 s 2 Ø8 x Ø10 x Ø10 x 700 For design capacities see calculation program NeoBA. 5

6 Function: NEO-BA1 can be used as a load bearing anchor in the same way as NEO-BA2, but are more commonly used as a horizontal anchor. The anchor is placed in the CoG to fix the element horizontally. This is done to control the temperature- and shrinkage movement. In situations when it is not possible to place the vertical anchors symmetrically in relation to the center of gravity, NEO-BA1 is used to take care of the rotation that arises between the suspended panel and the load bearing wall. Further, NEO-BA1 can be used as a purely load bearing anchor. Material: Stainless steel A2 and A4 Reinforcement: Mounting bar K500B-T, grid NP500AB-W NEO-BA1 can be found in following dimensions: NEO-BA1-6: mm, NEO-BA1-8: mm, NEO-BA1-10: mm Measurments [mm] NEO-BA1 NEO-BA1-6 NEO-BA1-8 NEO-BA1-10 Ø I a min. 50 min. 50 min. 50 c min. 55 min. 55 min. 55 H a + b + c a + b + c a + b + c U min. 60 min. 60 min. 60 B min. 90 min. 90 min. 90 h min. 25 min. 25 min. 25 Mounting bar K500B-T r 1 Ø8 x Ø8 x Ø8 x 700 s 1 Ø8 x Ø10 x Ø10 x 700 For design capacities see calculation program NeoBA. 6

7 Function: NEO-UB takes care of the adhesion forces during demoulding. NEO-UB is most suitable to use when the sandwich element is casted with its suspended panel facing down in the form. If the suspended panel is working as a façade it will be exposed to suction and pressure loads due to the wind, NEO-UB will transfer these loads to the load bearing wall. NEO-UB is fixed to the lower reinforcement grid before placement of the insulation. This ensures that the pin is fixed to the concrete before it starts hardening. Material: Stainless steel A2 NEO-UB can be found in following dimensions: NEO-UB-4: mm Measurements [mm] NEO-UB NEO-UB-4 Ø 4 U min. 60 I B min. 90 a U/2 + 5 c min. 55 7

8 Function: NEO-ÖB takes care of the adhesion forces during demoulding. NEO-ÖB is most suitable to use when the sandwich element is casted with its suspended panel facing up in the form. If the suspended panel is working as a façade it will be exposed to suction and pressure loads due to the wind, NEO-ÖB will transfer these loads to the load bearing wall. NEO-ÖB is inserted through the insulation, over an intersection in the reinforcement grid, and further in to the concrete. It important to do this as quickly as possible to ensure that the pin is fixed to the concrete before it starts hardening. Material: Stainless steel A2 NEO-ÖB can be found in following dimensions: NEO-ÖB-4: mm, NEO-ÖB-5: mm Mått [mm] NEO-ÖB NEO-ÖB-4 NEO-ÖB-5 Ø 4 5 U min. 60 min. 60 I B min. 90 min. 90 a min. 55 min. 55 c min. 50 min. 50 8

9 Basic placement of anchors and pins The arrangement to strive for is to have a horizontally placed NEO-BA-1 in the CoG of the element, with two NEO-BA-2 symmetrically placed on each side of the horizontal gravity line. NEO-UB and NEO-ÖB is placed in a square pattern, with a cc distance not more than 1200 mm, based on both the horizontal and vertical gravity lines. Anchors that are placed should also be aligned with one other both horizontal and vertical. Important is to keep in mind that the distances A max and B max are not exceeded. A max is the maximum distance for which the outer most anchor is placed in relation to the fixing point (F), and B max is the distance to the outer most placed pin from the fixing point (F). Alternative placement of anchors: 9

10 Large elements (multiple rows) In large elements it is important to think about which A max and B max that applies. If it is not possible to place the vertical anchors in the horizontal gravity line they should be placed underneath it instead. Small elements (two rows) The vertical anchors should be placed in the lower row. It can be necessary to place them a bit further up to be able to fit the mounting bars. Distance A is to place the centre of the anchor at a distance of A = L/ mm from the edge. Turned elements If an element needs to be turned for example during transportation, the load from the suspended panel needs to be taken care of in both directions. Therefore it needs to have anchors placed in both directions to withstand the loads. Slender elements As long as the centre distance between the pins is larger than 200 mm, they should be placed in pairs. Otherwise they should be displaced according to the picture. Min. width of the wall is L + 2 x 50 mm. 10

11 Cantilevering elements When the suspended panel cantilevers above the load bearing wall, it results in an area in which no pins can be placed to take care of wind loads or adhesion forces. This mean that amount of pins in the upper row should be increased. B = max. cc distance, Ö = distance from top edge cantilever part to the outer most pin. When Ö exceeds B/2, the distance A should be reduced to half in the upper row. The distance Ö is not allowed to exceed 900 mm. 11

12 Load bearing anchors When an opening gives the element a geometry with a separated part and forms a column like part of the element, the bearing anchor should be placed in this part. The anchor should be designed to withstand the load from the separated part. It should also be placed at the same height as the other vertical anchors. Narrow transitions over and below openings, i.e. doors and windows When the element and the opening do not admit a proper placing of pins, the pin should be placed anyway. Better one pin than nothing at all. 12

13 Thickenings (around door and windows) It is important to ensure that there is a space between the bearing wall and the supended panel. This is to allow movements between the layers. It is important not to forget the extra weight when designing the anchors. Extending panel around corner I the extending part of the element no anchors or pins should be placed. Behind this part of the element there should be a soft insulation. If the thickness of the element exceeds 400 mm a hard insulation should be used. When the thickness is larger than 400 mm a pin is placed in the CoG of the part that extends around the corner. In this case it is the pin that is regarded as the fixing point (F), and A max is measured from this pin. 13