Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
(OP)
I have a retaining wall that is ~2ft from the property line and approximately 7ft high. The contractor had gone ahead and installed piles prior to our involvement. The retaining wall is holding back about 6.5ft of sandy till.
We would typically use buttresses with piles set back from the retaining wall 4-5ft for overturning and span the retaining wall horizontally. However, because of the site limitations(and that the neighbour won't allow for us to tamper with his property or use steel tiebacks) does anyone have any other suggestions?
I thought about using a quasi-footing that cantilevered at the base out 2ft in order to allow for passive overturning resistance due to the weight of the backfill resting on the footing. We will include a few butresses but centerline offset will only be 1'10" which won't allow for much overturning resistance. Does anyone know of any good literature for determining that capacity of each piles resistance to overturning? or have any other ideas.
Thanks,
JrEng
We would typically use buttresses with piles set back from the retaining wall 4-5ft for overturning and span the retaining wall horizontally. However, because of the site limitations(and that the neighbour won't allow for us to tamper with his property or use steel tiebacks) does anyone have any other suggestions?
I thought about using a quasi-footing that cantilevered at the base out 2ft in order to allow for passive overturning resistance due to the weight of the backfill resting on the footing. We will include a few butresses but centerline offset will only be 1'10" which won't allow for much overturning resistance. Does anyone know of any good literature for determining that capacity of each piles resistance to overturning? or have any other ideas.
Thanks,
JrEng





RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
Any other ideas, i will check peck,hansen, thornburn. THanks pslem
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
Redi-Rock makes massive block retaining walls.
This one can be constructed to 10 feet without reinforcement.
http://w
If they use it, be sure to post some pictures... : ]
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
I am looking at getting some lateral resistance from the drilled piles but I don't have any good literature on lateral resistance of piles. To date I have only used coupled piles for overturning.
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
to support your design. We've run them using a crane or
large truck winch, steel cable, load cell, and a transit.
You can test multiple piles...
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
Why expect the certified work of a PE to be less expensive than a simple field test?
I strongly suspect that any reputable geo signing on
for this work will insist on at least two SPT/CPT borings,
possibly supporting lab test, and an LPILE analysis.
And the owner should expect a signed sealed report transmitting the recommendations.
And the geo engineer might STILL recommend a lateral load test for piles,
the installation of which he did not observe.
Consider that by accepting this work,
the PE is taking significant responsibility for the wall design and performance.
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
I still say this is something that should easily be computed by hand or with software like Civiltech.
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
A 'civil engineer' might be able to stamp someone else's drawings based on his own review,
but work in the subsurface is a different animal. Geo engineers are (with good reason!) very reluctant to provide
any recommendtions (especially for design) based on someone else's data. No thanks.
For my part, I would insist on generating my own field and laboratory data.
In my own practice I've run lateral tests on piles supporting floating piers (for example),
a dozen piles at a time, for a total cost of $3,000 to $5,000 with the analysis and report,
and made money doing so. The lateral load test is relatively simple,
beacuse the loads are much lower than foe an axial compression test, a single load cell is required,
and deflections are measured directly. I just charge crew time...
As for the means of analysis, there are many. However, I believe that an engineer's time and advice
are his stock and trade.
Clients sometimes forget that the value of an expert's involvement is not measured in hours or minutes.
That can lead to situations like the one under discussion.
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
PSslem quote: "Try Peck, Hansen and Thornburn for pile supported cantilever wall design. I have designed some with very little heel and a row of helical tension piles.
"
Thanks
Boyd
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations
RE: Cast-in-Place Concrete Pile Retaining Wall - Site Limitations