Water Pressure in 'Rock'
Water Pressure in 'Rock'
(OP)
We are looking at a 40ft braced cut. Water is about 10ft down, and claystone bedrock ranging 25-30 ft down. The bedrock is relatively impervious. In the overburden there is clearly a head of water that the wall must resist. Once you get into the claystone, do you think you continue to gain water head with respect to the wall or does the increase in head stop because the claystone is impervious?
As always, thanks
As always, thanks





RE: Water Pressure in 'Rock'
You are talking about a very complicated situation.
Mike Lambert
RE: Water Pressure in 'Rock'
RE: Water Pressure in 'Rock'
RE: Water Pressure in 'Rock'
Water in the joints of rock can transmit pressure a long way and the resulting pressure can be much higher than measured in the soil above.
Mike Lambert
RE: Water Pressure in 'Rock'
rock fractures can also convey water, as already stated.
f-d
¡papá gordo ain’t no madre flaca!
RE: Water Pressure in 'Rock'
Water pressure is controlled by the height of water. Why does being in rock make a difference?
RE: Water Pressure in 'Rock'
RE: Water Pressure in 'Rock'
cvg - if it is a true claystone and massive, I agree completely. However, most of the claystones that I've worked in have limestone or sandstone strata at varing intervals. Limestone in particular often has very complex hydrology.
Mike Lambert
RE: Water Pressure in 'Rock'
I understand that water can move a long way laterally, so in design of basement walls, we normally make conservative assumptions about the water level, rather than just use the level at the moment.