Active or At-Rest soil pressure - underground concrete utility vault
Active or At-Rest soil pressure - underground concrete utility vault
(OP)
Would the soil pressure on an underground utility concrete vault be active pressure or at-rest pressure? How do you typically distinguish between the two?
(Edit: I originally stated "passive" instead of "at-rest")
(Edit: I originally stated "passive" instead of "at-rest")






RE: Active or At-Rest soil pressure - underground concrete utility vault
If you assume that the soil acts as a viscous fluid, then movement is inherent. If you consider that the soil has some cohesive capability, movement is not inherent and you have to use your engineering judgement as to when movement occurs. The easier approach is to compute active, passive and at rest conditions and take the worst case.
RE: Active or At-Rest soil pressure - underground concrete utility vault
RE: Active or At-Rest soil pressure - underground concrete utility vault
RE: Active or At-Rest soil pressure - underground concrete utility vault
gjc
RE: Active or At-Rest soil pressure - underground concrete utility vault
RE: Active or At-Rest soil pressure - underground concrete utility vault
All of this exercise is an example of using engineering judgment and meeting the established standard of care for this realm of engineering in your area. As you can see, experienced engineers can have differing, yet logically correct opinions on both sides of such a subject. For compliance with an appropriate standard of care, it is important that you go through a process of evaluation prior to making your decision. In fact, the decision you make from an engineering perspective may actually be less important than the process you used to get there!
Further.....document, document, document whatever you do!
RE: Active or At-Rest soil pressure - underground concrete utility vault
RE: Active or At-Rest soil pressure - underground concrete utility vault
Maine Professional and Structural Engineer. www.fepc.us
RE: Active or At-Rest soil pressure - underground concrete utility vault
Calculation of the actual pressure distribution requires analysis of the interaction between the structure and the soil, including the effect of soil loads being applied in layers and compaction loads. This analysis will show that parts of the structure will have active pressures and parts greater than at rest. For a flexible arch structure a soil-structure interaction analysis is required to get even reasonably close to the pressure distribution that will develop[ in the actual structure. For a rectangular buried structure it depends on the size and flexibility of the structure, but in my opinion the more detailed analysis would often be worthwhile.
Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/
RE: Active or At-Rest soil pressure - underground concrete utility vault
RE: Active or At-Rest soil pressure - underground concrete utility vault