ARCHIVED REPORTS_2019 SOIL MGMT PLAN (JULY-REVISED)

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Murphy Parkway Warehouse December 19, 2016 Job No. 146-618 Page 8 pressures in backfilling of walls. The above loading is based on the assumption that hydrostatic pressures will not develop behind the walls. Walls should be drained as needed to relieve potential hydrostatic pressure. Where floor slabs or pavements adjoin the tops of walls, this should suffice to exclude significant water and further drainage measures would not be required. Only nonexpansive silts, sands or gravels should be used to backfill dock area walls. Clays should not be used in wall backfill. Use of 3/8-inch pea gravel or clean ¾-inch crushed rock for wall backfill is acceptable and can facilitate placement and compaction procedures. Backfill should be placed in level lifts not exceeding 12 inches in compacted thickness. Each lift should be compacted at a uniform near optimum moisture content to at least 90 percent of the ASTM D1557-02 maximum dry density. SLAB-ON-GRADE Thickness Requirements Because of stresses induced by truck cranes during panel erection a minimum six-inch thick floor slab is suggested for all floor areas. Our calculations indicate a six-inch thick slab would be capable of supporting typical 3000- to 5000-pound capacity forklifts carrying loads of less than 3000 pounds. If the floor will support more heavily loaded forklifts, or if high racks are used, then a six-inch slab may not be sufficient and our firm should be contacted for further recommendations. A modulus of subgrade reaction of 150 pounds per cubic inch may be used for the treated building pad in determining slab thickness for forklift loads. Due to the industrial use, we suggest the floor slab be reinforced with No. 4 bars spaced on 24-inch centers in each direction as a minimum. The reinforcement should be chaired at the middepth of the slab. The above discussion of slab thickness is based on use of quality strength concrete (4000 pounds per square inch minimum 28-day compressive strength). We suggest slab concrete be placed at a slump of three to four inches. Fibermesh® may be used in concrete to increase toughness, if desired. The floor slab should be thickened by at least 20 percent of the above recommended thickness at any drive-through doors. In addition, edges should be thickened wherever heavy materials will be stored within five feet of a free slab edge. A free slab edge is defined as any joint or edge where load transfer to adjacent areas is not provided, such as at building wall lines or undoweled expansion joints. The transition to the thickened edge may be achieved by tapering the slab thickness over a distance of five feet. Tapering may be accomplished by reducing the underlying aggregate base thickness at the edges. Joints Shrinkage crack control joints should consist of sawcut grooves penetrating at least one-fourth of the slab thickness. Control joints should not be spaced farther apart than about 30 times the slab thickness. Construction cold joints and expansion joints in the warehouse slab should include dowels to provide load transfer. Dowels should be three-quarters inch in diameter, 14 inches long, and spaced on 12 inch centers for six inch thick slabs. One end of dowels at expansion and crack control joints should be