SOIL LOADS AND HYDROSTATIC PRESSURE BASIC
What Are Soil Loads And Hydrostatic Pressure?
The notation H is used for lateral soil loads, loads due to hydrostatic pressure, and the pressure of bulk materials. Soil lateral loads and hydrostatic pressure are introduced in ASCE 7 Sec. 3.2 and IBC Sec. 1610.
Soil lateral loading most commonly occurs at retaining walls. It is relatively unusual for wood to be directly loaded by retained soils. One notable exception to this is permanent wood foundations, used in some regions of the United States.
While soil lateral loading will most often come from a geotechnical investigation report, ASCE 7 Table 3-1 provides design lateral soil pressures (in psf, per foot of soil depth) for a range of soil classifications.
Where retaining walls are provided, it is possible to develop hydrostatic pressure in addition.
Hydrostatic pressure is most often avoided by providing drains behind retaining walls. In cases where it is not possible to provide drains, design for combined soil and hydrostatic lateral pressures is required.
In conditions where hydrostatic lateral pressures can develop, it is possible to also have upward hydrostatic pressures on adjacent floor slabs. These upward pressures would also use the notation H in load combinations.
The notation H is also defined in ASCE 7 and the IBC to include pressure of bulk materials. Although no discussion of this use is provided, it is thought to include pressure due to storage of grain, aggregates, or other bulk solids that can exert lateral pressures.
What Are Soil Loads And Hydrostatic Pressure?
The notation H is used for lateral soil loads, loads due to hydrostatic pressure, and the pressure of bulk materials. Soil lateral loads and hydrostatic pressure are introduced in ASCE 7 Sec. 3.2 and IBC Sec. 1610.
Soil lateral loading most commonly occurs at retaining walls. It is relatively unusual for wood to be directly loaded by retained soils. One notable exception to this is permanent wood foundations, used in some regions of the United States.
While soil lateral loading will most often come from a geotechnical investigation report, ASCE 7 Table 3-1 provides design lateral soil pressures (in psf, per foot of soil depth) for a range of soil classifications.
Where retaining walls are provided, it is possible to develop hydrostatic pressure in addition.
Hydrostatic pressure is most often avoided by providing drains behind retaining walls. In cases where it is not possible to provide drains, design for combined soil and hydrostatic lateral pressures is required.
In conditions where hydrostatic lateral pressures can develop, it is possible to also have upward hydrostatic pressures on adjacent floor slabs. These upward pressures would also use the notation H in load combinations.
The notation H is also defined in ASCE 7 and the IBC to include pressure of bulk materials. Although no discussion of this use is provided, it is thought to include pressure due to storage of grain, aggregates, or other bulk solids that can exert lateral pressures.
