Slightly off topic, but concerning design column and middle strips, what would be the consequences of a middle strip which did not have sufficient reinforcement? Say the reinforcement was not installed correctly on site in the middle strip location.
Thanks, my thoughts exactly.
Attached link for those of you who are interested.
https://www.hilti.co.uk/medias/sys_master/documents/h18/9107965476894/Post_installed_shear_Reinforcement_HZA-P_Technical_information_ASSET_DOC_LOC_2521845.pdf
Torqued bolts anchored top and bottom set in an epoxy resin. Recessesed if necessary for durability or fire considerations.
The inclined methodology is based on a Hilti design which i am struggling to justify.
Thanks, yes enhance two-way punching shear in an existing slab.
In my opinion enhancing punching shear on an existing slab requires anchorage on both faces. Good to see agreement.
Hi People,
Wondering what your thoughts are on post fixing punching shear reinforcement with an anchorage only on one surface.
Typically we would post install a bolt with washers top and bottom mimicking the reinforced bar equivalent to enhance punching shear on an existing slab.
Recently a...
Update - I've thickened the slab at basement to counter the uplift in the area noted. The weight of the podium slab is also included, together they provide the FOS. Additional concrete but a foolproof solution. They can go with tension piles or ground anchors depending on the economics.
Thanks...
Thanks for the quick reply.
In general it does have a FOS.
The building over is a U shape, the basement is rectangular, so there is a podium area in the middle of the U where the dead load does not balance the uplift, although it is close. My thoughts are to span the slab at basement from...
Hi, I'm looking at designing a RC raft slab in a basement with thickenings under the columns. The basement slab is below the water table.
I'm thinking of designing the raft as two separate models. One as a suspended slab subjected to the uplift pressure in the negative gravity direction and one...
The development length calculation for prestressed strand / wire on this side of the water is similar, independent of concrete cover, section depth and provided reinforcement.
The EC2 code does give guidance on the spacing of pretensioned tendons / wires within the section, see attached. It...
Yes, working to EC2. There was a clause in the previous British Standard which had a similar requirement to check the stress at a bend in a reinforcing bar.
I'm open to correction but I think the check is generally not necessary because the minimum bend is sized not to crush the concrete when...
Thanks KootK,
There is space so I will be suggesting the beam is extended past the column.
I have looked at S&T but was coming up with a similar issue / non-issue in anchoring the tie.
There is a bar diameter gap between the bars so the stresses would reduce remote from the bend. There are...
Thanks for the quick replies.
Generally you would not need to anchor them all. However in this case the max BM moment is closer to the support than the required anchorage length, so they do end up being anchored into the support.
Sketch should be attached...
In designing a simply supported beam a scenario has arisen where there is a requirement to anchor 2 layers of bottom reinforcement at a column support with L bars, see attached sketch. It is probably similar to a situation which would arise on a deep beam close to a support, anchoring the...
If the cut on the limestone is vertical, then the assumption would be that there is no load from the limestone on the retaining wall. So the retaining wall is retaining the fill that you are adding. I must be missing something but why is the retaining wall required in the first place? Could a...
You could jack the slab upwards, install the beams and pack, release the jacks, slab will bear on the beams.
Alternatively fit some flat jacks between the beam and the underside of the slab. Both options will have the benefit of attracting both the self weight and the imposed live load from...
