8310 RIM DR Geotech Report 2018-01-02 MF Import

Gcotechnicni k:ngincering B`'u�uation 8310 Rim Drive- R��mi Novc^ibcr R, 2004 RMI Pilc No. �IGO•l 1'ngc 9 SI»bs-On-Gr:idc Slnh-on-grade nrens should be preparcd as recommendcd in thc Site Preparntion and Grading subscction of this report. ARcr rcmoval of loosc soil, thc subgrade should be compactcd to a dcnsc, non- yiclding conditiun. Prior to structurol fili placcmcnt, thc subgrndc should bc proofrollc� with a heavy. rubbcr-tircd picce of equipmcnt, tu idcntif}• sofi or yicldii�g arcas thst requirc rcpair. Arcas obsen�cd to pump or wcave should bc re�vorked to structural fill speci�cations or be c�cnv�tcd and replaced �eith pmperly cumpacicd s�nic�ural fill. \Ve rca�mmcnd tl�at all tloor slahs bc underlain hy at least 6 inches of Gec-drnining snnd rn� era��cl lor use :is a capillury break. A suitnble vapor barricr. such as heavy plastic sheeting (10-mil minimum), should be placed ovcr the sand or gravel. A 4-inch-thick crushcd rock blanket may bu uscd to co��er the vnnor barricr to protect it, to :iid in curing Ihe concrete, and to prevent conerete paste from Icaking do�cn into thc capillary brcak matcrial through joinis or Icars in ihc vapor barricr. 1'hc capillary break should bc dcsiencd to drain into thc fnunda�iun dcain s�stcm. Subsurfacc �Valis and Rctaining Wulls l he lateral pressurc uc�ing on substu'face and retaining ��alls i; dependent on the naturc and density uf the soil bchind the walf, ihe amount of later.il ��all movement which can occur as backfill is pinced, wall drainage conditions, t.nd the inclin�tion of Qic hackfill. I'vr walls th�t arc frce to yield at ihe top at least imc thnusandth of thc height of the wall (active condition), soil pressurcs ��ill bc less than if movement is iimited bv such t;�ctors ns ��:ill stitliiess or bracing (nt-resl condition). 1L'e recommend tha� walls supporting horizon�nl b+�ckfill and not subjcctcd �o hydros�ntic forces be designed using a Irinngular earth pressurc distribution eyui��alent to that escrted b� a Iluid �vith a density of 3$ pcf for yiclding (F+ctive condition)walls, and 60 pcf for nun-yiclding(nt-rest condition)��'nlls. I�hesc recommcndcd lutcral enrth pressum; nrc bascd un the assumption of a horizont. . gmunJ surfncc actjaccnt to �hc ��nll liir a distancc of at Icast thc subsurfnce hcight of thc ��II, and do not accouni for ,urcharges. Additional latcrnl carth pressures should bc considcred for surchargc loads acting adjacent to the subsurface walls and within a dist�nce equal to ihe subsurface height of the wall. This would include the cf7ccts of surcharges such ns tralYic loads, floor slab loads, slopes, or olhcr surfacc loads. The lateral pmssurcs on ��'alis may he ;esisted hy t�iction hchvicen �he tiwndation and subgrade soil, and by passive RMI Associates, Ltd.