4326 CRESCENT AVE 2025-07-14 - Laserfiche WebLink

Foundation parameter Summai Descri Lion *1)esi n value Net.Allowable Hearing Canaci T-_ 2,500 Vsf Friction Coefficient 0.35 Lateral Resistance 350 pcf •1)etnils regarding,)he use orthdse pimmetemam wovid'id in the section above. 5.5 Slain 0n-Grlide Slab-on-grade floors should be supported on stibgrades prepared as reconimetlded in the "Site Preparation and Grading!'section of this report. The existing fill observed .in the tipper 3.0 to 4.0 feet of the site is in a loose condition acid contains enough organics that it will not be suitable for support of slab-on-grade floors. Prior to coclstruetion these unsuitable soils should be removed from under now slab areas. Tininediately below the floor slab,we recommend placing a four-.inch thick,capi-Nary break layer of clean,free-draining, coarse sand or fine gravel that has less than three percent.passing the No. 200 sieve. This material will reduce the potential for upward capillary movement of water j through the underlying soil and subsequent wetting of the floor slabs. The drainage material j should be placed in one lift and compacted to a fimi and unyielding condition, The capillary break. layer will not prevent moisture intrusion throtegtl the stab.caused by tivater vapor transmission: Where moisture by vapor ttnnsmission is undesirable, such as covered floor areas,a common practice is to place a,durable plastic mcnibrane on the capillary break layer and E thon cover the membrane-with.a layer of clean sand or fine gravel to protect°it from damage during construction, slid aid in uniform curing of the concrete slab. It should be noted that if the . sand or gravel layer overlying the membrane is saturated prior to pouring the -club, it will not j assist ill uniform curing.of the slab, and.may serve its a water supply for.moisture transmission through the slab and -affcetitlg float covcrittgs. Additionally, if talc:' sand is'too dry, it can ?: effectively drain the fresh concrete, thereby lowering its strength. Therefore,; in our opinion, is covering the membrane with a layer of sand or gravel should be avoided. 5.6 Lower Level and wilding!'Falls The magnitude of earth pressure development on below-grade wails, such as basement or retaining walls,will.greatly depend on the quality of the wall.backh.11 and the wall drainage. We !. rcconttl7cnd placing and compacting will[ backfill as structural fill. Walt backfill below stnicturally loaded.areas,such its pavements or floor slabs,should be caitipacted to a mioinium of 95 percent of its maximum dry density, as determined by ASTM Test Designation 13-155? (Modified proctor). In unimproved areas,the relative compaction can be reduced to 40 percent. I. To guard against hydrostatic pressure development, drainage must be installed behind tho wall. We recoininend that wail drai.nagc consist ofalilininititll E2 inches of clean rand and/or gravel with less than three percent fines placid against the back of tiie wall. In addition,a dixiiiage collector systecla coclsistiug,-of 4-inch periorated PVC; pipe should be, placed behind the wall to provide an :ages t:aginceritsg,L Ppgc ttl 2S3-it43-7ttg0 f