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0 <br /> I METHOD ONE Prevent adfreezi <br /> ng by separating the roundat�on surface from frost-susceptible <br /> ( soil. Place non-frost-susceptible materiai against this surface. Granular material (sand and gravel) <br /> that is clean (less than 5 percent fines passing #200 sieve) is considered non-frost susceptibie <br /> material. Silt and silty soil is especially highly frost-susceptible. Granular material must be free-� <br /> Idraining and permanently well-drained into subsurface drain lines to prevent water from <br /> accumulating and freezing in foundation backfill. Poor-draining backfill can potentially freeze into a <br /> solid mass of ice mixed with backfill. This can cause adfreezing and heave of foundations. Drain <br /> ( lines must meet recommendations in the WATERPROOFING section of this report. <br /> I METHOD TWO Anchor foundation walls to spread footings for heave resistance. The maximum <br /> anticipated frost line depth must be above the footing top to provide resistance. A zone of <br /> urtifrozen soil must remain between the frost line and top of footing: Soil in this zone must be free � <br /> Ito compress due to downward movement of the overlying frozen soil zone. This compressed soil <br /> exerts a downward force upon the top of the footing, which counteracts the upward adf�eezing <br /> (within the frost zone) induced shear strain on the foundation wall. Foundation backfill must be <br /> ' compacted to maximum dry soil density to minimize its compressibility and therefore its heave <br /> potential. This method should be carefully reviewed and approved by a structural engineer before <br /> implementation. <br /> METHOD THREE Place polystyrene foam insulation boards horizontally over frost-susceptible <br /> foundation backfill material. Bury boards deep enough to prevent crushing by any wheel loads. <br /> Soil overlying the boards must be separated from foundation surfaces to prevent acffreezing. <br /> Board thickness must be designed using degree/day/Btu methods and its thickness should be 2 or <br /> more inches. Boards must extend horizontally outward from foundations to a distance greater than <br /> the frost penetration depth. <br /> WATERPROOFING ' <br /> As stated in the GROUND WATER section of this report, water was detected in Borings 1 and 2 <br /> near depths of 8 and 9 feet respectiveiy. The Boring Logs reveal that supraglacial till appears to <br /> have both oxidized and unoxidized soil zones. The oxidized soil zone extends down to depths <br /> near 13 feet, and it is not related to a persistent g�ound water condition. The oxidized zone <br /> overlies the unaxidized soil zone, which is associated with a persistent ground water condition. <br /> Architectural design must provide waterproofing and capillary break protection for the building. <br /> Rain and melting snow are the two main bulk water sources that can wet building interiors. A <br /> properiy sized gutter and downspout system will collect water falling on a building's roof and <br /> remove the water well away from the building to discharge points such as ground surfaces or storm <br /> water drains. Without this system, water will fall from the roof and splash against the building's <br /> exposed walls, then drain along it by gravity down to the building's foundation. This water can <br /> saturate, soften, and weaken the foundation's support soil and dampen the basement. Ground <br /> surfaces surrounding the building must be graded away from the building using 5 percent minimum <br /> slopes to direct storm water away from the building. Settlement of graded ground immediately <br /> surrounding building walls may occur well after construction by settlement of soil in trenches or <br /> Allied Project 05039 14 July 31, 2005 <br />