I try to use the Hilti Profits to design the masonry fixing. Could you answer the following inquiries?
- The Hilti design report (page 3) is showing that the tension load (Brick breakout) is 4.15KN. It seems Profits use the tension of two bolt rather than one bolt. Do you know why?
- The Hilti design report (page 3) is showing that the capacity of tension (Brick breakout) is 3.6KN. The brick type in design report is solid clay brick Mz, NF. I believe the 3.6KN tension is for 2 anchors. When I look at the datasheet of HY270 (page 10), I can not find either 1.3kN or 3.6kN on the SC2 brick table. Could you tell me how Profits get 3.6kN?
- Could Profits check masonry breakout of double brick cavity wall? If the brick width 115mm, could I input the wall thickness 230mm to simulate double brick wall?
- If there are double brick wall, can I double up the tension resistance when using HY270 with Hilti anchor embedment into the second brickwork? Such as HY270 with M12 HAS-U + HIT-SC, 80mm embedment into second course brickwork corresponding to 1.4kN tension capacity and 3.6kN shear that I highlight in the attachment. Could I double up the 1.4kN tension capacity and 3.6kN shear capacity to be 2.4kN tension capacity and 7.2kN capacity if there are double brick?
Hi Steven,
Thank you for your answer.
Please find our answers to your questions below. We recommend that you reach out to our Anchor Design Services Team via https://www.hilti.com.au/content/hilti/A2/AU/en/engineering/engineering-services/anchor-design.html so we can perform a more detailed assessment.
1.Due to the moment My, the anchors no1,3 is in tension while no2,4 is in compression zone. Hence the tension load acting on the anchor group is 2.075+2.075 = 4.15kN
2.According to ETAG 029 C.5.2.1.4, 
From the ETA 19/0160 table C9 for solid clay brick Mz, NF the NRk,b = 4.5 kN
NgRk = αg,NII x αg,N┴ x NRk = 1.0 x 2.0 x 4.5 = 9.0kN
NRd,b = NRk,b / ƔM,m = 9.0 / 2.5 = 3.6kN
3. and 4.
If it is double layer of wall, as long as there is no gap between the first and second skin/leaf/layer the there is no any changes in the data, the only changes will be the base material thickness which means it is treated as 1 thicker wall, but it will not double up the capacity of the anchor. If there is a gap/cavity between it, then it must be assumed as a single layer/skin. HIT-SC is only approved to be used in hollow brick. We do not have any tested data to evaluate if there is cavity between the first and second layer of brick wall.
In order to take the loading, base plate could be increased and increased the anchor spacing to as model below.
We hope the above is enough to answer your questions, but please reach out to us here or though our Anchor Design Services Team if you need further clarifications.
Regards,
Ask Hilti Team
Australia