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Home My WebLink AboutCT 05-14; LA COSTA OAKS NEIGHBORHOOD 3.1; FINAL REPORT OF TESTING AND OBSERVATION SERVICES PERFORMED DURING SITE IMPROVEMENTS; 2009-10-15nnI n_I .. :'. •GEOCON . 0 ' INCORPORATED S GEOTECHNICAL CONSULTANTS (410>) Project No. 06105-52-26 October 15, 2009 5 ', '0 5 S - Chad Grimm Construction •, S - •- 3248 Avenida Anacapa Carlsbad, California 92009 Attention: Mr. Chad Grimm - Subject: VILLAGES OF 1A COSTA - THE OAKS NORTH LOT 8 1 - RECREATION AREA . CARLSBAD, CALIFORNIA FINAL REPORT OF TESTING AND OBSERVATION SERVICES . PERFORMED DURING SITE -IMPROVEMENTS . Dear Mr. Grimm: . .• 5, In accordance with your request and our Proposal No. LG-09098 dated April 15, 2009, we have provided compaction testing and observation servics during the, installatiOn of site improvements for 'Lot 81 - , Recreation Area within the Villages of La Costa - The Oaks North development. We performed our services during the period of May: 5, 2009 through September 21, 2009. The scope of our 1services • included: •. Performing in-place density tests on an "on-call" basis during storm drain and sewer, main trench backfill operations;' . 0 'S .S S ...' .0 Performing in-place density tests during the minor regrading of the open space west of the recreation area. Additionally, performing in-place density ,tests during the preparation of the S . subgrade for sidewalk and the subgrade for the c0iicrete flatwork placed around the pool deck; -. Providing geotechnical consultation services during improvement operations; S • Performing laboratory tests for concrete compression testing'on two sets of concretcylinders' we fabricated during the placement of the foundation system; and - Preparing this final report of improvements. 5 , •0 0 ''' S 5 - To aid in preparing this report, we have reviewed the following, report an& plans associated with the project improvements: 0 • ' Final Report of Testing and Observation Services performed During Site Grading, Villages of 0 ' ' La Costa—The Oaks North, Lot 81—Recreation Area, Carlsbad, California"prepared by 0 Geocon Incorporated, dated May 16, 2608 (Project No. 06,105-52-20).. 0, 6960 Flanders Drive' U San Diego, Californid 92121-2974 • Telephone (858) 558-6900 U '5Fax (858) 558-6159 S 0 - :- '- 5 ,_ ,0 ' , -, . •''_ H Development Plans for La Costa Oaks North, Recreation Center, in La. Costa, California, preparedby Dahlin Group, latest revision dated October 12, 2007 (Project No. 745.008). We performed in-place density tests using a nuclear gauge in accordance with ASTM Test Procedure D 2922. The results of the in-place density tests are presented in Table I. The results of the laboratory tests are summarized on Table II. We also performed compression tests on concrete cylinders in accordance with ASTM C 39. Appendix A presents the results of the concrete compression tests. In general, the results of the in-place density tests indicate that the utility trench backfill, sidewalk subgrâcie, subgrade for the flatwork pool deck, and regrade operations possess adry density of at least 90 percent of the laboratory maximum dry density near to slightly above optimum moisture content at the locations tested. The re'sults of the in-place density tests are summarized in Table I and laboratory test results are summarized on Tables II. We corrected the laboratory maximum dry density and optimum moisture content on fill soil being tested containing rocks larger than 3/4 inch Using methods suggested by .AASHTO T224 and others. The values of maximum dry density and optimum moisture content presented on Table I reflect these corrections. .. . - I Based on observations and test results, it is the opinion of Geocon Incorporated that the construction of site improvements, which is the subject 'of this report, has been performed in substantial conformance with the recommendations of the project gebtechnical report. Additional grading and/or improvement installation performed at the site should be accomplished in conjunction with our observation and testing services. Grading plans for future grading should be reviewed by Geocon Incorporated prior to finalizing. Trench and wall backfill and sidewalk subgrade should be compacted to a dry density of at least 90 percent of thelaboratory maximum dry density near, to slightly above-optimum moisture content. This office should be notified at least 48 hours prior to commencing additional grading or backfill operations. . • Adequate drainage provisions are imperative. Under no circumstances should water be allowed to pond. adjacent to improvements. Finish grades should be established so that drainage water is directed away from foundations, pavements, curb and gutters, and sidewalks to controlled drainage devices; Irrigation of landscape areas adjacent to pavements should be monitored to 'provide just enough water to support plant life. • . . 11 t : Should you have any questions regarding this report, or if we may be of further service, please contact r iheundersignedat your convenience -. - Very truly yours, GEOCON INCORPORATED . Michael C.Eitwine i adr • Shawn r Senior Staff Geologist CEG1778 - GE 2714 i - r / - MCEAS:SW:dmc - 11. ; (4/del) Addressee : OFEWSS/O cc CEii~FIED Co No. 2h4 ENGINEERING U-1 Exp.o~/30/11 M 'GEOLOGI Cr OF OFC • T-.- • '- 1 - 7 - t_. - I -' ,- - --. - I S - 0 0 I - •1 I - ' •-I. :- Sow ( -• •- - - -. - - 0 •0 - - Project No 061055226 3 October 15 2009 I - TABLE - . SUMMARY OF FIELD DENSITY TEST RESULTS Elev. Plus Field Field Field Reqd. - or ' 3/4" Adj. Adj. Dry Moist. Rel. Rel. Depth Curve Rock MDD OMC Dens. Cont. Comp. Comp. Test No. Date Location (ft) No. (%) (pCf) (%) Rib 1 07/15/09 Lot 81; W ofRec. Area - 463 - 1 20 136.6 7.5 125.3 7.3 92 90 RG ,2 07/15/09 Lot 81; WofRecArëa 462 . 1 40 1428 5.8 133.8 5.4 94 . 90 -f t • : - . • S S. - .: - - -' . - -- - , •• + ,•, - , Project No. 06105-52-26 S •,.• • / •- + S • S. - • , - • ..• October 15, 2009 • ,• , • . , . / S • • • S +5+ 'S +5 5 55-S. 5 _y S + TABLE 1, - SUMMARY OF FIELD DENSITY TEST RESULTS Elev. Plus Field Field Field Req'd. or 3/4 Adj. Adj. Dry Moist. Rel. Re!. Depth Curve Rock MDD OMC Dens. Cont. Comp. Comp. Test No. Date Location No. (°) (pef) (%) (pcf) SD 1 ' 05/05/09 'Lot 81; SE Corner of Site --- -4 1 30 139.6 6.7 128.0 7.6 92 . 90. SD 2 05/05/09 Lot 81; SE Corner of Site -2 1 30 139.6 6.7 125.3 - 9.1 90 90 SD 3 05/05/09 • Lot 81; SE Corner of Site - -5 1 30 139.6 6.7 126.1 7.8 90 90 SD 4 05/07/09 Lot 81; SE Comer OfSite • -3 :1 40 142.8 5.8 \ 131.7 6.1 92 - 90 SD 5 05/07/09 Lot 81; SE Corner of Site -1 1 20 136.6 7.5 122.8 7.3 90 90 SD. 6 Manhole 05/07/09Lot81;SDMan Riser -2 1 30 139.6 • 6.7 127.9 6.2 • 92. 90 • - -- 'S Project No. O6105-52-26 October 15, 2009 - • ...........e..........,...................... TABLE I . . .. SUMMARY OF FIELD DENSITY TEST RESULTS Elev. - Plus Field Field Field Reqd or 3/4" Adj. Adj. Dry,Moist. Rel. Rel. Depth Curve Rock MDD oc Dens. Cont. Comp. Comp. Test No. . Date Location (ft) No. (°"°) (Pcf) (%) (pcf) SO 1' 08/20/09 Lot 81; Pool Deck-East . 0 . 1 30 139.6 - 6.7 128.7 6.2 92 90 SG 2 08/20/09 Lot 81; Pool Deck - South 0 1 30 139.6 6.7 127.9 6.7 92 90 SG 3 08/20/09 Lot 81; Pool Deck - West 0 1 30 139.6 6.7 128.8 . 6.4 92 90 SO 4. 08/20/09 Lot 81; Pool Deck-North 0 1 30 139.6 . 6.7 129.1 6.4 92 90 2 Project No. 06105-52-26 October 15, 2009 - .. . . . . . . - ...................i..s..i.....i........... S .5 S S S S S TABLE S S - SUMMARY OF FIELD, DENSITY TEST RESULTS S .Elev. Plus Field Field Field Reqd. - - or 3/4" Adj. Adj. Dry Moist. .. Rel. Rel. S Depth Curve Rock 'MDD OMC Dens. Cont. -, Comp. Comp. Test No. Date Location No. (°"0) (pcf) (%) (pCf) M. SM 1 05/22/09 Lot 81; Plumbing/Sewer Tie-In - -3 1 20 136.6 7.5 123.2 7.7 90 90 SM 2 05/28/09 Lot 81; SE of Building . -2 18 20 143.5 6.2 130.4 7.2 91 90 SM 3 05/28/09 Lot 81; SE of Building S -. -2 g 30 145.91 5.5 131.6 5.6 90 90 .5..- . .. - . .5 .5 5- - Proje6tNo. 06105-52-26 . S.. 5 October 15, 2009 010-0 0 00 .6 TABLE I' • : SUMMARY OF FIELD DENSITY TEST RESULTS N . . Elev. Plus . Field Field Field Reqd. or 3/4" Adj. Adj. Dry Moist. Rel. Rel. Depth Curve Rock MDD OMC Dens. Cont. Comp. Comp. Test No. Date Location (ft) No. (%) (pcf (%) • (pcf) . SW 1 09/16/09 Sitio Corozon 38+80 - 0 1 30 139.6'.6.7 132.1 7.1 95 90 : SW 2 09/16/09 Sitio Corozon 39+20 0 1 30 139.6 6.7 134.2 6.9 i96 , 90 • S - . . . . ) N - • S / . - - - S . S S - -. • - • S S N • • .5 5 5 .S • -'55 - 5 5 . S • S S S S S - • . . . - • S 5, S Project No. 06105-52-26 ,- October 15, 2009 S • • S S — s N S - •••S•••I•••S•S•f•••I•S••SS••Ô•S••••••OI•SS• TABLE EXPLANATION OF CODED TERMS -TEST SUFFIX A, B, C.... : Retest of previous density test failure, following moisture conditioning and/or recompaction. - STRIKE-OUT • S Fill in area of density test failure was removed and replaced with properly compacted fill soil. - PREFIX CODE DESIGNATION FOR TEST NUMBERS S.. RG REGE SD - STORM DIN - SG - SGE SM - SEWER MAIN SW SIDEWALK -CURVE NO. - = Corresponds to curve numbers listed in the summary of laboratory maximum dry density and optimum moisture content test results table for selected fill soil samples encountered during testing and observation. - ROCK CORRECTION For density tests with rock percentage greater than zero, laboratory maximum dry density and optimum moisture content were adjusted for rock content. For tests with rock content equal to zero, laboratory maximum dry density and optimum moisture content values -are unadjusted. -TYPE OF TEST • - • S . SC: Sand Cone Test (ASTM D 1556) • S - NU: Nuclear Density Test (ASTM P 693 8) 5 . • - • - OT: Other S S S - ELEVATION/DEPTH ( S Test elevations/depths have been rounded to the nearest whole foot. S S S S S • 55 • - Project No. 06105-52-26 • • : - October'15, 2009 - Sample No 6Description Maximum Dry Density (pci) Optimum Moisture Content (% dry weight) 1 Olive brown Silty SAND 430.0 9.3 18 Light reddish brown, Silty SAND 13&9 7.6 APPENDIX A SUMMARY OF CONCRETE COMPRESSIVE STRENGTH TEST RESULTS Location: THE OAKS NORTH LOT 81— RECREATION AREA Test: COMPRESSION TESTING Material Supplier: HANSON I Date Made: 6/4/2009 Mix Number: 3032500-300-5.77 SACK Age (minutes): 65 Concrete Temperature, °F: 60 Unit Weight, pci: N/A Slump, inches: 5 Air Content ,_%: -- Laboratory Number 275-1 275-2 275-3 275-4 Date Tested 6/11/09 7/2109 7/2/09 HOLD Diameter (in) 4 4 4 4 Cross-sectional Area (in) 12.57 12.57 12.57 12.57 'Maximum Load (lbs.) 24,030 45,900 47,400 -- Compressive Strength (psi) 1,910 3,650 3,770 Age Tested (days) 7 28 28 ' HOLD Required 28-Day Strength (psi) 2,500 2,500 2,500 2,500 Defects (specimen or cap), -- -- -- -- Break Type * Type 5 Type 5 Type 2 -- *Break Type: I = Cone; 2 = Cone and Split; 3 = Columnar; 4= Shear; 5 = Side Fracture; 6 = End Fracture (Pointed) Location: THE OAKS NORTH LOT 81— RECREATION AREA Test: COMPRESSION TESTING Material Supplier: HANSON I Date Made: 06/04/09 Mix Number: 3032500-300-5.77 SACK S Age (minutes): 90 Concrete Temperature, °F: 71 ' Unit Weight, pci: Slump, inches: 4 3/4 Air Content, Laboratory Number 276-1 2762 276-3 276-4 Date Tested 6/11/09 7/2/09 7/2/09 ' HOLD Diameter (in) . 4 4 4 - Cross-sectional Area (in2) 12.57 12.57 12.57 '12.57 ,Maximum Load (lbs.) 29,370 52,700 52,505 -- Compressive Strength (psi) 2,340 4,190 4,180 -- Age Tested (days) 7 28 28 HOLD Required 28-Day Strength (psi). 2,500 2,500 2,500 HOLD Defects (specimen or cap) -- -- -- . -- Break Type * Type 5 Type 2 Type 5 -- *Break Type: I = Cone; 2 = Cone and Split; 3 = Columnar; 4 = Shear; 5 = Side Fracture; 6 = End Fracture (Pointed) Project No. 06105-52-26 " ' October 15, 2009