1000 INDUSTRY ST 2018-01-02 MF Import

� January 23, ?005 Project No. T-56>9 � I Thc majority of the esisting fill soils at the site contain a sufficient amount of fines (silt and clay size particles), { which will make them difficult to rc-compact as structural fill �i�hen too wet. The ability to use the soil from site I excavations as structural fill will depend on the soil's moisture content and the prevailing weather conditions at the time of construction. If grading activitics will take place during thc winter season, the owner should be iprepared to import free-draining granular material for use as ,tructural fill and backfill. Dctailed recommendations regarding these issues and other geotechnical desien considerations are pro��ided in the follo�ving sections of this report. Our recommendations should be incorporatcd into the final design drawings and Iconstn�ction specifications. I41 Site Preparation and Gradin� To prepare the site for construction, thc thin surface !ayer of grass and roots should be stripped and removed Gom � the site. Organic material �vill not bc suitable for use as structural fill, but may be used for limited depths i:: nnn- structural areas. SurCacing stripping deptl�s of one to t�vo inches should be expected to remoee the grass and root layer. IOnce stripping operations are complete, cut and fill operations to cstablish desired building grades can be initiated. Prior to placing fill, wc recommend all csposed surfaces bc obsen�ed by a qualified geoteclmical Icngincer to d�termine if any isolated soft and yielding areas are presenL The contractor should be prepared to � rroofroll subgrade areas �vith heavy construction equipment, as directed by the geotechnical cnoineer. Cut areas that will provide direct support for new construction should also be observed to verify the soil subgrade is suitable � for support of the planned construction. If excessively yielding areas are obsen�ed and cannot be stabilizcd in place by compaction, the affected soils i should be excavated and removed to finn bearing ai�d grade restored with new structural fill. If the depth of excavalion to remove unstable soils is excessive, use of a F;eotextile reinforcing/separation fabric, such as Lnyfield Plastics LP180 or equivalent, can be considered in conjunction ��ith swctural fill. Our e�perience has shown i that, in general, a minimum of lS inches of a clean, granular structural fill over the geotextile fabric should establish a stable Uearing surface. ( Our study indicates the majority of the soils at the site contain � sufficient enough percentage of fines �silt and � day size particles), which will make them difficult to re•comparr as swctural fill if they are roo wet or too dq�. Acco:dingly, the ability to use the suils from site excavations as structural fill will depend on their mois[nrc icontent and the prevailing �veather conditions wL-en sitc-crading activitics take place. Soils that aze roo �vet to propedy compact can be dried by acration duriug dp�weather conditions. � If grading activities are platmed during thc wet winter months, or if they are initiated during the summer and extend into fall and winter, thc o�vner should be prepare�9 to import wet weather structural fill. For this purpose, we recommend importing a granular soil that mcets the following grading requirements. fU.S.Sicre Size Percen[Passin 6 inches 100 I No.4 75 maximmn No.200 5 maximum' *13a�ed on thc 3/4-inch fraction. ! Pagc No. d i � ��