1601 N Bristol St - Phase 1 - Plan

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Mr. Amir Houriani Project No. 32-6235-00 1601-1607 N. Bristol Street August 29, 2022 CITY OF SANTA ANA Planning and Building Agency Ar ',v Page Approved FOR PERMIT ISSUANCE Master ID: The recommended lateral pressures above assume that the walls will be fully draine i},ea permanent drainage system to prevent build-up of hydrostatic pressures. Additional lateral pre walls subject to potential surcharge loads from sloping retained earth, traffic loading, or adjacent structures should be incorporated into the design. All retaining walls shall be provided with a drainage system in order to minimize the potential for future hydrostatic pressure buildup behind the walls. The drainage system may consist of a perforated pipe surrounded by a minimum one foot of free draining, uniformly graded, aggregate material, and wrapped in a filter fabric such as Mirafi 140N or equivalent. The filter fabric should overlap approximately 12 inches or more at the joints. The subdrain pipe should consist of a perforated, four -inch diameter, rigid Schedule 40 PVC or ABS (SDR-35) or equivalent with perforations placed down. The excavated bottom and subdrain pipe behind any retaining wall should be observed by the geotechnical engineer or his/her representative prior to the placement of aggregate or compacted backfill. Subdrain pipes at the base of the retaining wall should outlet to an acceptable location. As an alternative, the use of gravel pockets and weepholes is an acceptable drainage method. Weepholes shall be a minimum of two inches in diameter, placed eight feet on center along the base of the wall. Gravel pockets shall be a minimum of one cubic foot in dimension and may consist of three- quarter inch to one -inch crushed rocks wrapped in filter fabric. Where retaining walls are to be constructed adjacent to property lines, there may be inadequate space for placement of a standard perforated pipe and aggregate drainage system. Under these circumstances, a prefabricated drainage composite system such as a Miradrain or equivalent may be used. The composite drainage material may be connected at the bottom of the wall to gravel pockets a minimum of one cubic foot in dimension (12"L x 12"W x 127) placed eight feet on center along the base of the wall. A collector is placed in the gravel pockets which directs collected waters through the wall by way of a subdrain pipe to a sump pump underneath the slab. PAVEMENT SECTIONS New pavement sections will be constructed as part of the proposed development. Based on review of the design plans, the pavement will consist of permeable sections which may comprise pervious concrete or porous asphalt at the surface layer. Due to the liquefiable nature of the on -site soils, the use of permeable sections, which allows for stormwater infiltration, is not recommended. As an alternative, the pavement may comprise flexible (asphalt) or rigid (Portland Cement Concrete) sections. For areas where new paving is to be placed, the subgrade should be scarified to a depth of 12 inches, moistened as required to about 3% above optimum moisture content, and recompacted to 90% of the maximum dry density as determined by ASTM:D-1557. The client should be aware that removal of all existing fill in the area of new paving is not required; however, pavement constructed in this manner will most likely have a shorter design life and increased maintenance costs. The following pavement design sections are based on an assumed "R" Value of 30. Once site grading has begun, an "R" Value should be obtained by laboratory testing to confirm the properties of the subgrade soils prior to placing pavement. Traffic loading is anticipated to be primarily light vehicles. The Traffic Indices used for the pavement design sections provided below are estimates and should be verified by the project civil engineer. n �Q A.G.I. Geotechnical, Inc. • 16555 Sherman Way, Suite A • Van Nuys, CA 91406 Office: (818)785-5244 • Facsimile: (818)785-6251