Exterior Large Equipment Pad with deep frost depths | Eng-Tips Frost heave isn't really caused by just the moisture in the soil freezing (and the subsequent small volume increase) It becomes an issue when ice lensing happens This is when a horizontal layer of ice forms and continues to grow in thickness as water is drawn into the freezing layer through capillary action in the soil If you have non-frost susceptible soil (large granular fill), capillary
Is Frost Depth Always Required? | Eng-Tips No, frost depth is not always required if what you are supporting can withstand the movement However, for most pipe racks we have designed we have gone to frost depth
Which soils are most susceptible to frost heaving? | Eng-Tips However there is still some potential for frost heave, especially of there are variations in the soil As mentioned in the other thread, would be best to insulate footings having inadequate cover (side of wall below grade and laterally over footing) to maintain soils thawed under footing
Frost Heave Calculation | Eng-Tips Frost heave can easily be several inches in northern states with frost-susceptible (silty) soils and a shallow water table or just poor drainage On the other hand, dry, clean, sand or gravel may freeze without heaving Heave can vary a lot from year to year depending on moisture conditions and weather
Top or Bottom of Footing? | Eng-Tips Frost depth always has been and should be to the bottom of the footing You are trying to avoid a condition where frost occurs in the soil directly under a footing and in which case the soil expands (or rather the moisture freezes and expands within the soil matrix) and dislocates the footing
How is frost depth determined calculated? | Eng-Tips If frost depth is determined for a county, how many tests do they perform before the county is satisfied with their estimate of frost depth? Is climate change taken into account in frost depth calculations? It seems to me that there are a ton of variables that could affect frost depth, so am just curious how these numbers are typically determined
Flowable Fill and Frost Heave | Eng-Tips Frost heave can only occur when all of the following three conditions are present: 1) the soil is frost susceptible (large silt fraction), 2) sufficient moisture is available (soil is above approximately 80 percent saturation), and 3) sub-freezing temperatures are penetrating the soil
Neglecting Passive Pressure in Frost Depth | Eng-Tips When calculating the passive resistance of the soil below the frost depth is it proper to consider the passive pressure based on the actual depth or should the passive pressure be calculated on the actual depth minus the frost depth? For example if the frost depth is 2' and my passive pressure
Floating slab on grade detail at exterior door | Eng-Tips For a floating slab on grade, what is best practice at an exterior door? I assume the slab edge should get extended to the outside face of the wall Does the slab edge need to be thickened? If so, how much, or should it be turned down onto the strip footing grade beam? It seems to me that if