4719 BELVEDERE AVE 2016-01-01 MF Import

June 28,206 Uavid and Judy King L&A Job No. 6A07G Page 16 To resist against sliding, the friction force betwccn the footings nnd the subgradc scils may be calculatc� based on a coefticicnt of friction of 0.60. The nlwvc soil parametcrs are ultimate values b.ucd on a fully draincd backfill of thc wnlls, nnd proper fuctors of safety should bc applicd in the design of thc basement walls against sliding and overtuming failures. A vertical drainage blanket, nt Ieast 12-inch-thick horizontally, consisting o1'clean, Gee-draining, pca gravel or washed gnvel should be placed ngainst basement and retaining wulls to prevenl accumulation of groundwatcr behind and buildup of hydrostatic pressure ag;unst the walls. T'his drainage blanket should be compactcd to u non-yielding stute with u vibrntory cumpactor. The top 18 inches of thc backfill may consist of compacted, on-site soils. SWctutal fill should be used for the remaining backfill of basement and retaining walls. Heavy compaction equipment should not bc nllow�cd within the walls of a horizonLll distuncc equal to that of Uie wall heiE;his. A 4-inch perforatcd PVC foating drain pipe, as recommcnded in the DRAtNAGE CONTROL section of this report, should be providcd for the bascmcnt and retaining walls. The drain lines sho.ild bc hydr�ulically connected to the drainage blanket bchind the walls. SLAIT-ON-GRADE FLOORS Slab-omgrade Iloors, if used, should be placed on firm subgmde prepared as outlined in the SI'fG PRBPARATION ANU fiGN1iRAL BART7IWORK and L':^ STRUCTURAL FILL scc;tions of q�is rcport. Whcrc moisturc control is cr.'tical, thc slab-on-grade tloors should be placcd on a capillary brcak which is in tum placcd on thc compacicd subgrndr.. The cupillary brcuk should consist af a minimum four-inch-th;ck layer of fiee-draining gravel or crushed rock containing no morc thmi 5% by wcight passing the No. 4 sievc. A vnpor barrier, such ns a 6-mil plastic mcmbrune, �nay be placed ovcr the capillury brcak, as rcquired, to kcep moisture from migrating un�r,�nl�. LIU & ASSOCIATCS, INC.