The project is a a row house dig-out - from about 3 feet of crawl space to an 8 foot basement. The common shared foundations are of rubble stone on this three story home.
I am looking for comments - theoretical and practical - on the attached 3 different underpinning techniques, assuming that...
I am attaching a drawing with 3 different underpinning options for a common shared rubble stone wall of a three story home
Option A is preferred by most engineers, most labor intensive
Option B was suggested by several experienced underpinning contractor and at least one engineer endorses this...
I see one slide with two images of rubble stone foundation walls. The pits are dug and the walls are being held up by what appears to be wood (plywood and/or 2''x stock). My question is what next? Does one leave this support to be cast into the concrete pier and the drypack? Thank-you.
Continuation of previous post:
I was thinking that one could use, for each pit, a horizontal metal plate with 2’’x4’’ studs wedged vertically to support the rubble foundation wall above. The plate and the studs would be left to become part of the new foundation.
If so, then one could also use a...
Hello All,
Does anybody have any practical tips and/or solutions on how to support a rubble stone foundation wall during the pit underpinning process? I am assuming that the 100 year old mortar will not (completely) keep the wall together under gravity.
I cannot see how this support can be...
Dicksewerrat,
Are you referring to the potential need for a pump, either for a french drain leading to a pit or for a potential bathroom in the new basement?
I did a preliminary check with the city and I think I will not need a pump for a bathroom and may need one for a sump pit.
I also...
This is extremely helpful.
Questions for PEinc and anybody else who wishes to reply:
1. Can you explain the use of louvers? Why not just omit spaces between rows of sheeting?
From Ratay: “It is advisable to use louvered boards at all times to in order to enable backfilling behind the boards...
Any suggestions on a structural engineer for this in Montreal Quebec Canada?
And with a good engineer on board, do you have any thoughts on me using a very good general contractor for this project, with no underpinning experience? (I have worked with him before on numerous occasions and he is...
PEinc this is extremely helpful. I checked:
• details in Temporary Structures in Construction by Ratay (although 1st edition)
• details in the free FHWA geotechnical 3-volume underpinning manual online and
• your “recipe” described in this old thread...
Thanks all.
PEinc, is was hoping for a reply from you. I watched your presentation on Recent Building Collapses in Philadelphia. I also watched the following presenation: NYC Department of Buildings - An Underpinning Symposium.
Do you know where I can see a proper set of drawings for this...
Jayrod12 no need to apologize.
I am posting here to get independent professional advice - good and bad, pro and con.
This project is not uncommon around here, just like in Brooklyn, DC, Philly, etc.
What is normally done is a ramp is dug from the back service alley down to the back of the...
We are looking into digging out a basement from about 3 feet of crawl space on our row house that dates from about 1910. Our 3 story building has a rubble stone foundation and is “attached” on both sides to other 3 story houses. Both neighbors have crawl spaces too. In parallel to coming to...
Mike,
And by minimizing the eccentricity of the angle bolts at the steel beam, I am assuming you are referring to placing the bolts in the web of the steel beam as close as possible to the new LVL?
Appreciated!
Hi,
I have an existing steel beam which currently sits on a column
I would like to demolish column and let beam into a new LVL beam.
Can I use two angles:
1. Field bolted to either side of web of existing beam and
2. Lag screwed / bolted through face of new LVL
We want avoid any filed...
