temp. retaining wall using a beam in concrete and 1" 'street plate'
temp. retaining wall using a beam in concrete and 1" 'street plate'
(OP)
I need advice on designing a temporary retaining wall on a construction site. I want to utilize the H-beams (W27x102)that extend out of 48" diameter concrete shafts (secant wall) approximately 3' to prop up a 'street plate' 8'x20'x1".
So the retaining wall will be 8' high with the bottom 3' supported by the H-beams that are spaced 3' on center. Behind the wall, engineered fill will be placed to the top of the wall then sloped another 2' for a total height of 10'. Once up to grade, a delmag RH32 drill rig (143 kips/track) will crawl out and drill a wall of sand shafts that is 10' offset of the secant wall. The edge of the track of the drill rig will sit within 1' of the top of the slope and be approximatly 3' away from the wall.
I attached a sketch of the design but the 1" plate is only 8' high so the top 2' will have to be sloped from the top of the wall to get the full height and the rig will have to be moved over 2 more feet.
So the retaining wall will be 8' high with the bottom 3' supported by the H-beams that are spaced 3' on center. Behind the wall, engineered fill will be placed to the top of the wall then sloped another 2' for a total height of 10'. Once up to grade, a delmag RH32 drill rig (143 kips/track) will crawl out and drill a wall of sand shafts that is 10' offset of the secant wall. The edge of the track of the drill rig will sit within 1' of the top of the slope and be approximatly 3' away from the wall.
I attached a sketch of the design but the 1" plate is only 8' high so the top 2' will have to be sloped from the top of the wall to get the full height and the rig will have to be moved over 2 more feet.





RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
You also need to check the high weld stresses at the weld between the Hpile and the plate.
Have you checked the weight of this thing?it sounds very very heavy and may require special lifting equipment (crane e.t.c.)
For the cantilever bending you will have an effective width which will be much less than the width of the plate.
You have not shown the extra 2' of soil and this needs to be allowed for as a surcharge.
How are the sand columns compacted? If it is by any dynamic means then you may get additional loading from the rig when the weight is dropped e.t.c.
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
Have you considered some added bracing, say a 3" dia. pipe from the outboard flange of the H pile up to say 2/3 up the side of the plate, as a strut to take away the bending problem at the connection of plate to pile. This would permit the plate to sit higher in elevation also.
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
I suggest you hire someone with experience in designing shoring walls.
www.PeirceEngineering.com
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
I guess your question is the one I am trying to answer...Will the wall overturn?
I attached a better sketch that is closer to something feasible.
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
Can you weld some extensions onto the top of the W27's?
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
I will probably design something at a 45d angle off the back of the beam to about the midpoint of the street plate.
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
www.PeirceEngineering.com
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
Use a Boussinesq distribution to determine the loading on the plate from the crane. It is conservative, but with a heavy piece of equipment that probably costs a fair amount of money, conservative is good.
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
I'd secure that rig to some anchor off to the right of your drawing. No point in having it side off the bank.
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
The secant piles are being drilled right now. The beams are placed inside the shaft and then it is filled with concrete. Once the secant wall is complete (2 weeks), the plates will be placed against the beams and braced (somehow) so the fill can be brought up to elevation so the sand shafts can be drilled and finished at the proper elevation.
Stay posted, I have a dwg that I am working on that will detail the wall and I will post it tonight or tomorrow.
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
Consider, much wider mats to distribute that crane load, maybe even using those steel plates for that purpose, and driving in some stiffer deeper structural elements. If you do this without calc's those bigger mats (ones that bridge between both tracks) may be all that save you from disaster.
You also need to be darn sure that that secant wall was designed for the crane being that close to it.
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
- I can't see that the #11 bar contributes anything. I think it actually hurts things.
- You do not show any welds, but I assume there are some (there need to be)
-weld the diagonal C6 to the W27 web, not the flange
-The horizontal C6 'waler' isn't going to do much bent about
its weak axis, if you need a waler, provide a real
serviceable waler
- Get somebody involved who knows shoring work to help you out.
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
www.PeirceEngineering.com
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
I am not saying you don't have a good concept. What I am saying is that I have done shoring for over 20 years, and you need to take your concepts to an experienced shoring engineer who can design the system to do what you want to do. The members of this forum have great ideas based on a lot of experience and can give you good suggestions, but not a complete design, which what you need.
I offer this post with great respect to everyone in this forum, including ewhpeps, and hope I have offended no one. My fear is that with out a proper design someone could get hurt.
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
www.PeirceEngineering.com
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
Basically you got the 3' of W27 to work with. The 2-TS4's welded to each flange are 6'tall and tied together at the top by a 3/8" plate. The 8' tall street plates will bear on TS4's. On each W27 will be an angled TS5 that helps support the TS4's.
The secant wall is completely done. The sole purpose of this retention system is for temporary support to drill the sand shafts from a higher elevation. Due to space restrictions we cannot move forward on the permanent concrete wall right now.
RE: temp. retaining wall using a beam in concrete and 1" 'street plate'
www.PeirceEngineering.com