Pressure Under a Mat Foundation 1

[ocgeo]

It seems that for a large mat foundation say 100ft x 100ft, Westergaard and Boussinesq theories may be very conservative, as the soil pressures will tend to 'travel' more laterally with great depths, creating a bridging effect.

There must be research on pressure cells at various depths, say at 50 and 100 feet under a 100 x 100 foot mat that would disprove (or prove) Westergaard and Boussinesq theories?

Is anyone aware of such research?