The URL can be used to link to this page

Home My WebLink AboutCT 10-01; SEA BREEZE VILLAS; ROUGH GRADE COMPACTION REPORT & REVISION; 2012-05-07RCM ; STRATA—TECH FAX NO. : 714 5212552 May. 09 2012 12: 14Ptl P1 crit'-Q( H,l N. 714-521-5611 (EOCQNSULTANTB FAX 714-521-2552 7372 Walnut Avenues Unit F Buena Park, California 90620 May 7, 2012 W.O. 262310 Tony Sfrecldo 19196 Sierra Isabela Irvine, CA 92603 Subject: Revision to Rough Grade Compaction Report for Proposed Multi Family Residential Development, 391 Tamarack Avenue, Carlsbad, California Reference: Rough Grade Compaction Report for Proposed Multi Family Residential Development, 391 Tamarack Avenue, Carlsbad, California., by Strazatech, Inc. Dated February 7, 2012 Pursuant to your request, STRATA-TECH, Inc. has observed the re-graded slab sub grades for the proposed development. PLACEMENT OF PERIMETER FILL Compacted fill was placed outside the building pads adjacent to the existing property line walls in order to provide vehicular access that was necessary to construct the new property line walls. The graded pad sub grade was disturbed during the course of perimeter grading. The disturbed slab sub grades were re graded and recompacted in order to rehabilitate the slab sub grade. Only ten pads were refurbished, the two isolated pads at northwest ( BLDG C)were left for a later day. OBSERVATIONS DURING GRADING The slab sub grade for the buildings was visually observed, probed and tested to confirm compliance. STRATA TECH GEO 1145212552 Page 1 Roland Acufia Principal ROM STRATA—TECH FAX NO. : 714 5212552 May. 09 2012 12 16PP1 P1 5TRATATE13H,INCI OEOCDNSULTANTS TunySfrcdo 2 W.O.262310 Slab Sub gmdg Obscrvation Reppft May 7.2OJ2 REGULATORY COMPLIANCE All cuts, fills and processing of original slab sub grades under the purview of this report have been completed under the observation of and with selective testing by STRATA-TECH. Inc., and found to be in compliance with the Grading Code of the City of Carlsbad. The completed work has been observed by STRATA-TECH, Inc., and is considered adequate for the development. Our findings were made and recommendations prepared in accordance with generally accepted professional engineering practices, and no further warranty is implied nor made. C; This report is subject to review by the controlling authorities for this project We appreciate thifl opportunity to be of service to you. Respectfully submitted: STRATA-TECH, Inc. I 2012-05-08 23:34 STRATATECHGEO - 7145212552 RUM : STRATA—TECH FAX NO. : 714 5212552 May. 09 2012 12:16PM P2 ;STRATATECH,INC. auuNuLTNTs Tony Sfredo W.O. 26230 Slab Subrade Obscrvation Report May 7.2012 COMPACTION TEST RESULTS pg 11.3 112.9 1 91% 5/7112 I Building Pad 2 Building Pad pg 10.9 111.7 I 90% 5/7/12 3 Building Pad pg 11.8 111.9 I 909/0 5/7/12 - 4 Building Pad pg 12.1 112.3 I 91% 5/7/12 2012-05-08 23:34 STRATA TECH GEO 7145212552 ROM STRATA-TECH FAX NO. : 714 5212552 Mae. 09 2012 12:17PM P3 2012-05-08 2335 STRATA TECH GEO 7145212552 a ______ _____ 714-521-5611 I / / S T R A T A - T E C H 7 1 NO. 562-427-8099 L/ / GEDCN6ULTANTS FAX 714-521-2552 7372 Walnut Avenue, Unit F,Buena Park, California 90620 February 7, 2012 Tony. Sfredo 21 Woodcrest Irvine, California,92603 L W.O. 263210 Subject: Rough Grade Compaction Report for Proposed Multi Family Residential Development, 391 Tamarack Avenue, Carlsbad, California Reference: Geotechnical Engineering Investigation of Proposed Multi Family Residential Development, 391 Tamarack Avenue, Carlsbad, California., by Stratatech, Inc. Dated August 3, 2010 Gentlemen: Submitted herewith is the Rough Grade Compaction Report for the subject site. The grading operation was cqnducted between January 26, 2012 and February 7, 2012, utilizing the recommendations of the referenced report. Observations of the grading were provided by STRATA-TECH, Inc. PLACEMENT OF STRUCTURAL FILL Compacted fill was placed on the subject site to provide adequate support for the proposed 2 story Multi Family Residential Development OBSERVATIONS DURING GRADING Preparation for pl,acement of a compacted fill included overexcavation to approximately 3 feet• below pad grade, and 5-feet beyond the building foundation to provide a minimum of 1-foot of compacted fill unIer the footings of the proposed building. Prior to placement of fill, the bottom was made level, scarified, watered and tamped smooth. Subsequent fills were placed in 6 to 8 inch loose lifts and compacted to a minimum of 90 percent. The pads were raised approximately 3 feet in the back to allow for drainage toward Tamarack Street. - The driveway portion of the site was left low to allow for placement of footing excavation soil. / STRATA-TECH,INC. ra ED CON S LI L.TANTS Tony Sfredo 2 W.O.262310 Rough Grade Compaction Report February 7. 2012 Final rough finish grade is approximately 6 inches below the finish floor grade in order to allow placement of sand and concrete for the slab-on-grade building. Approximate limits of grading for the pad area is -shown on Plate A. TESTING Maximum density optimum moisture relationship determinations were performed for each soil type encountered during grading operations. Test results were as follows: Laboratory Standard: (ASTM: D-1557-91) 4 inch dia. mold; 1/30 cu.fi.vol.; 5 layers-25 blows per layer; 10 lb. hammer dropped 18 inches Soil Type Classification Optimum Ikfoistui c % Hax. Diy Density lbs/ft3 I Light Brown Fine Sand 12 124.0 I Import, Brown Sand 10 126.0 Compaction tests were performed a minimum of every 2 feet and/or 500 cubic yards of compacted fill soils placed. These tests were performed in accordance with ASTM: D-2922-91 (nuclear gauge) or ASTM: D- 1557-04 (sand cone) test methods. The test results are summarized in Table I. The approximate test locations are shown on Plate A. Areas not tested Were probed to show adequate compaction. FOUNDATIONS ON COMPACTED FILL The proposed building may be supported by continuous spread footings placed a minimum depth of 18 inches below lowest adjacent finish grade utilizing an allowable bearing value of 1,500 pounds per square foot. This value is for dead plus live load and may be increased 1/3 for total including seismic and wind loads where allowed by code. Type Minimum Depth (inches) Minimum Width (inches) Bearing Value (psI) Increase Maximum Width Depth (psf/ft) (psf/ft) Continuous 18 12 2000 180 440 3500 It is recommended that all footings be reinforced with a minimum of four No. 4 bars (2 top and 2 bottom). The structural engineer's reinforcing requirements supersede if more stringent. STRATA-TECH,INC. 13 E CI C 0 N S U LT A N T S -g Tony Sfredo 3 W.O.262310 Rough Grade Comnaction Renort February 7. 2012 Footing excavations shall be observed by a representative of STRATA-TECH, Inc. prior to placement of steel or concrete to verify competent soil conditions. If unacceptable soil conditions are exposed mitigation will be recommended. LATERAL DESIGN An allowable lateral bearing value against the sides of footings of 250 pounds per square foot, per foot of depth; to a maximum of 2,000 pounds per square foot may be used, provided there is positive contact between the vertical bearing surface and compacted fill. Friction between the base of the footings and/or floor slabs and the underlying material may be assumed as 0.35 times the dead load. Friction and lateral pressure may be combined, provided either value is limited to two-thirds of the allowable. The above values may be increased by one-third for short durations of seismic and wind loads. FLOOR SLABS The surface soils have a medium expansive potential. Slabs on grade shall be supported on engineered fill compacted to a minimum of 90 percent relative compaction. Slabs should be reinforced with at, least No. 4 bars 18 indhes on center both ways. The soil should be kept moist prior to casting the slab. However, if the soils at grade become disturbed during construction, they should be brought to approximately optimum moisture content and rolledto a firm, unyieldingcondition prior to placing concrete. In areas where a moisture sensitive floor covering will be used, a vapor barrier consisting of a plastic film (6 m11 polyvinyl chloride or equivalent) should be used. The vapor barrier should be properly lapped and sealed. Since the vapor barrier will prevent moisture from draining from fresh concrete, a better concrete finish can usually be obtained if at least 2 inches of wet sand is spread over the vapor barrier prior to placement of concrete. HARDSCAPE AND SLABS Hardscape and sltb subgrade areas shall exhibit a minimum of 90 percent relative compaction to a depth of at least 1 foot. Deeper removal and recompaction may be required if unacceptable conditions are encountered. These areas require testing just prior to placing concrete. POST-GRADING SERVICES During constructin of the residence, it is recommended, and at times required by the regulatory agency that the following be observed and/or tested by the geotecimical engineer: S T R AT A - T E C H , IN C. GEOCONSULTANTS 19 Tony Sfredo 4 W.O.262310 Rough Grade Compation Report February 7, 2012 Excavations of footings Backfill of interior slab areas Backfill of interior trenches Backfill of exterior utility trenches Hardscape, and pavement subgrade It is the responsibility of the deve ero schedule the required observations and testing. REGULATORY COMPLIANCE All cuts, fills or' processing of original ground under the purview of this report have been completed under the observation of and with selective testing by STRATA-TECH, Inc., and found to be in compliance with the Grading Code of the City of Carlsbad. The completed work has been observed by STRATA-TECH, Inc., and is considered adequate for the development. Our findings were made and recommendations prepared in accordance with generally accepted professional engineering practices, and no further warranty is implied nor made. This report is subject to review by the controlling authorities for this project. We appreciate this opportunity to be of service to you. Respectfully subthitted: STRATA-TECH, Inc. U-i No. C 46606 1j . 06-30-13 *Ij OF Roland Acuña Larry Finley Principal RCE 46606 Enclosures: Cotnpaction Test Results Ple A - Compaction Test Map 714-521-5611 S T R A T A - T E C H , I N C 562-427-8099 G E 0 C C N S,U L T AN T s FAX 714-521-2552 7372 Walnut Avenue, Unit F,Buena Park, California 90620 COMPACTION TEST RESULTS Test No Location Below Proposed Giade Ut) Moisture Content Ay Unit Weight (Lbs/ft) Soil Tipe %Relative Compaction l)ate 1 Building Pad 5 12.3 112.9 I 91% 1/27/12 2 Building Pad 4 11.8 111.7 I 90% 1/27/12 3 Building Pad 3 12.8 111.9 I - 90% 1/27/12 4 Building Pad i -12.1 112.3 I- 91% 1/27/12 5 Building Pad. 4 13.2 112.6 I 91% 1/27/12 6 Building Pad, 4 .12 112.1 I 90% 1/27/12 7 Building Pacf 4 12.1 111.9 I 90% 1/30/12 8 Building Pad 3 11.5 112.3 I 91% 1/30/12 g Building Pad 2 . 11.6 . 112.5 I 91% 1/30/12 10 Building Pad PG .., 0.2 112.8 1 91% 1/30/12 11 Building Pad PG 10.3 112.6 I 91% 1/30/12 12 Building Pad..1 i2.1 113.2 Il 93% 2/01/12 13 Building Pad. P.G 12.1 112.3 11 92% 2/01/12 14 Building Pad 3 .. -13.5 113.2 Il 2/02/12 15 Building Pad 3.5 9.9 113.7 II 93%2/03/12 16 Building Pad,2 . 10.1 113.5 II 2/03/12 17 Building Pad 4 -10.2 - 112.2 II 92% 2/06/12 18 Building Pad: 1 i.97 112.8 1 92% 2/06/12 19 Building Pad: P.G 8.2 111.9 11 92% 2/07/12 20 Building Pad P.G . 8.5 112.5 Il 92% 2/07/12