Thread holes in concrete

[thinfourth]

Shield bolts = Oh god NO NO and NO again i've used them before and are an utter pain in the hoop

Thunderbolts = I have concerns about them going in and out of what is probably **** poor concrete

Rim inserts = maybe

resin in sockets = I think that is the way togo i just to get a really big drill

 

[thinfourth]

How about using a steel plate with captive nuts set into the concrete using countersunk fittings? A bit more work initially but anything fitted would be easily removed and refitted

That would be the best way togo but i can't be hooped to dig out the concrete to get the plate flush with the floor

As even a wee bit of sticky up will result in me tripping over it and swearing alot

 

[Agrismith]

Shield bolts = Oh god NO NO and NO again i've used them before and are an utter pain in the hoop

Thunderbolts = I have concerns about them going in and out of what is probably **** poor concrete

Rim inserts = maybe

resin in sockets = I think that is the way togo i just to get a really big drill

Tbf if you aren't in a hurry a normal sds will stick some big holes in concrete providing you use a new sharp bit
Installed a large processing plant on a farm and everything was bolted down with hundreds of m24 expanding bolts all installed with a small sds drill

 

[Pete.]

We drill a lot of 32mm with SDS max. Lead with a 16mm bit and follow with a 32 and they go very fast, plus the expensive 32mm bit lasts a lot longer.

 

[mtt.tr]

M12 thunderbolts very good I have them holding up some 6 ton concrete panels whilst I demolish them. The M16 ones are standard scaffolding tie fare. They hold a lot.

The stated shear capacity is huge, would be interesting to know the pull out force In different materials

 

[Agroshield]

As even a wee bit of sticky up will result in me tripping over it and swearing a lot

With the internally threaded sockets, you can set the top of them below the concrete surface and, as stated, a button head screw will keep the dirt out. Then they would be totally flush. When installing them, put a greased bolt or stud into them so you do not block the threads as the glue you use squidges out of the hole. You do not need to buy too exotic a glue: cheap epoxy resin would do, even Isopon (or any polyester filler). The secret is to clean the hole very well. Hoover all the dust out (sellotape a small tube to the hoover so it goes right to the botttom). Give the hole a light scrub with a round wire brush. Hoover again.

 

[willie.macleod]

Be careful with Thunderbolts, the size of the hole is critical as is the quality of the concrete. There were failures of these also in the rock climbing world which got publicity a few years ago. Personally I would be going down the resin fixed socket route.

 

[500e]

Some TB come with a drill if you buy a box
We use resin the quality of the concrete will not be so important as load is spread & resin seeps into it
See #3 #17 #26

 

[Revs1972]

We use the thunderbolt types ( M16 x 150 ) on the majority of our structures. That way we can zip them back out and fill the holes with non shrink grout to reinstate the studio floor. Whilst I would use the bolts a second time, I wouldn’t want to reuse a hole as per your case ( gut feeling rather than anything scientific),
I’d go with the resin in sockets . Remember at school they had them in the sports hall floor in the basketball / football courts. You used them to fix the posts for tennis / badminton so they got used a couple of of times a day / 5 days a week so they are pretty reliable