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HomeMy WebLinkAboutCT 04-26; ROBERTSON RANCH PA 16, 17 & 18; PAVEMENT DESIGN REPORT;Geotechnical . Geologic . Coastal . Environmental 5741 Palmer Way • Carlsbad, California 92010 • (760) 438-3155 • FAX (760) 931-0915 . www.geosoilsinc.com March 16, 2011 W.O. 5949-E-SC Brookfield San Diego Builders, Inc. 12865 Pointe Del Mar, Suite 200 Del Mar, California 92014 Attention: Mr. Greg McDonnell Subject: Pavement Design Report, North Fork Avenue (Stations 101" to 18+00) and Cascade Street (Stations 10+00 to 12+"), Portion of Planning Area 16 of Robertson Ranch, Carlsbad, San Diego County, California Dear Mr. McDonnell: - In accordance with your request, GeoSoils, Inc. (GSI) has prepared this supplemental pavement design report for asphalt concrete (AC) pavement at the subject site. This report also includes alternative recommendations for the use of subgrade enhancement geotextiles (SEG's), if desired. The scope of services provided in preparation of this report include a review of the referenced reports and documents (see the Appendix), an evaluation of the pavement section for the subject area, and preparation of this report. PAVEMENT DESIGN Pavement section evaluation was based on traffic index (TI) values provided by O'Day Consultants (improvement plans). Pavement sections were evaluated in general accordance with the California Department of Transportation (Caltrans) Highway Design Manual of Instructions and the City of Carlsbad Standard Drawings (see the Appendix). Pavement sections presented are based on the aforementioned criteria and resistance value (R-value) data (see the attached Figures 1 through 3), evaluated from soils exposed at, or near, final subgrade elevations within the subject areas. R-value testing was performed in general accordance with the latest revisions to the Department of Transportation, State of California, Material & Research Test Method No. 301. The collection of representative subgrade samples was perforemed by a representative from this office and under the supervision of the City inspector. C3• ASPHALT CONCRETE PAVEMENT Structural Section Traffic Indices (TI) were provided by the project civil engineer (O'Day Consultants, 2006) as 5.0 for the subject traffic areas. A-values (see attached Figures 1 through 3) ranging from 13 to 17 were evaluated' for representative subgráde soils onsite and used in pavement design. In addition to a standard asphalt over aggregate base pavement section, an alternative section, using SEG's per Section 614.5 of the Highway Design Manual (State of California, 2008), and the State of California (2009). The recommended pavement sections, provided in general accordance with the City guidelines (City of Carlsbad, 1993), and the State of California (2008, 2009), are presented as follows: Standard Pavement Section: Asphalt/Aggregate Base I LW AC'? B1 I ZAPPROXIMATE TI(1) SUBGRADE THIKNE S 4J -, i TRAFFIC AREA - , R-VALUE ( / (Inches Cascade Street, Sta. 10 to 12 (Sample obtained from Sta. 10) 5.0 14 4.0 6.0 / 1 North Fork Avenue, Sta. 10 to 14+00 (Sample obtained from Sta. 13) 5.0 13 4.0 6.0 North' Fork Avenue, Sta. 14 to 18+22 (Sample obtained from Sta. 16+—n 5.0 17 4.0 6.0 Per O'Day Consultants (Improvement plans) Per Carlsbad (1993) Denotes Class 2 Aggregate Base H >78, SE >25) City Of Carlsbad SHOP DRAWING REVIEW The PPW renyshoperwotcdra1ng(erof any drawing of the Con&acto's plaid or equipment) shall not in any way be deemed to release the Contractor from M re ponsi1*lty for complete and accurate pei.anoo of the Vit In eccoidance wW the Contract Drmvtngs and Spedflcatlons. Neither shall such approval release the Contractor form any labWty placed swon 1*0 byp onofCoo" C3 it: O .NSI.AMENDANDRESUBMI1' - - ç3: .IIS.S.MAKE CORRECTIONS NOTED NO EXCEPTIONS TAKEN Brookfield San Diego Builders, Inc. W.O. 5949-E-SC Portion of Planning Area 16, Robertson Ranch March 16, 2011 File: e:\wp9\5900\5949e.pdr4 Page 2 GeoSoils, Inc. Alternative Pavement Section: Subgrade Enhancement Geotextile (SEG) :• TABLE 2 ASPHALT!C CONCRETE (A.C.)/AGGREGATE BASE(A.B.)/SEGY O)CMATE gUBGF : TI' THICKNESS THICKNESS (CalTrans Cascade Street, Sta. 10 to 12 (Sample obtained from 5.0 20 4.0 Bi, - Sta. 10) North Fork Avenue, Sta. 1O to 14 (Sample obtained 5.0 20 4.0 Bi, 1325 . i from Sta. 13) North Fork Avenue, Sta. 14 to 18 (Sample obtained from 5.0 20 4.0 5.0 Bi, B25 / Sta. 16) Per O'Day Consultants, (Improvement plans) Effective R-value when using SEG HP 570, or equivalent (State of California, 2008, 2009) Per Carlsbad (1993) Denotes Class 2 Aggregate Base R >78, SE >25) Class B1, Mirafi HP 570, or equivalent; Class B2, Mirafi FW500, or equivalent This alternative includes design pavement sections using SEG's per Section 614.5 of the Highway Design Manual (State of California, 2008), and the State of California (2009). Subgrade enhancement geotextile (SEG) used shall be either Mirafi HP 570 (Class Bi), or FW500 (Class 132), or equivalent. All SEG's shall be placed per the manufacturers guidelines. General Installation Considerations All pavement installation, including preparation and compaction of subgrade, compaction of base material, and placement and rolling of asphaltic concrete, shall be done in accordance with the City guidelines, and under the observation and testing of the project geotechnical engineer and/or the City. . The recommended pavement sections are meant as minimums. If thinner or highly variable pavement sections are constructed, increased maintenance and repair may be needed. The recommended pavement sections provided above are intended as a minimum guideline. If thinner or highly variable pavement sections are 'constructed, increased maintenance and repair could be expected. If the ADT (average daily traffic) or ADTT (average daily truck traffic) increases beyond that intended, as reflected by the TI used for design, increased maintenance and repair could be required for the pavement section. Consideration should be given to theincreased potential for distress from overuse Brookfield San Diego Builders, Inc. Portion of Planning Area 16, Robertson Ranch FiIe:e:wp9\5900\5949e.pdr4 p CeoSoiis Inc. W.O. 5949-E-SC March 16, 2011 Page 3 of paved street areas by heavy equipment and/or construction related heavy traffic (e.g., concrete trucks, loaded supply trucks, etc.), particularly when the final section is not in place (i.e., topcoat). Best management construction practices should be followed at all times, especially during inclement weather. PAVEMENT GRADING RECOMMENDATIONS General All section changes shall be properly transitioned. If adverse conditions are encountered during the preparation of subgrade materials, special construction methods may need to be employed. A GSI representative shall be present for the preparation of subgrade, base rock, and asphalt concrete. Subgrade Within street and parking areas, all surficial deposits of loose soil material shall be removed and recompacted as recommended. After the loose soils are removed, the bottom is to be scarified to a depth of at least 12 inches, moisture conditioned as necessary, and compacted to 95 percent of the maximum laboratory density, as determined by ASTM test designation D 1557. . Deleterious material, excessively wet or dry pockets,, concentrated zones of oversized rock fragments, and any other unsuitable materials encountered during grading shall be removed. The compacted fill-material shall then be brought to the elevation of the proposed subgrade for the pavement. The subgrade shall be proof-rolled in order to ensure a uniform firm and unyielding surface. All grading and fill placement shall be observed by the project soil engineer and/or his representative. Base Rock Compaction tests are required for the recommended base section. Minimum relative compaction required will be 95 percent of the laboratory maximum density as determined by ASTM test designation D 1557. Base aggregate shall be in accordance with Section 26 of Caltrans Standard specifications (California Department of Transportation, 2006), for Caltrans Class 2 aggregate base. Paving Prime coat may be omitted if all of the following conditions are met: 1. The asphalt pavement layer is placed within two weeks of completion of base and/or subbase course. Brookfield San Diego Builders, Inc. . W.O. 5949-E-SC Portion of Planning Area 16, Robertson Ranch March 16, 2011 File:e:\wp9\5900\5949e.pdr4 Page 4 GeoSoils, Inc. Traffic is not routed over completed base before paving. Construction is completed during the dry season of May through October. The base is kept free of debris prior to placement of asphaltic concrete. If construction is performed during the wet season of November through April, prime coat may be omitted if no rain occurs between completion of base course and paving and the time between completion of base and paving is reduced to three days, provided the base is free of loose soil or debris. Where prime coat has been omitted and rain occurs, traffic is routed over base course, or paving is delayed, measures shall be taken to restore base course and subgrade to conditions that will meet specifications as directed by the geotechnical consultant. Drainage Positive drainage shall be providedfor all surface water to drain toward the curb and gutter, or to an approved drainage channel. Positive site drainage shall be maintained at all times. Water shall not be allowed to pond or seep into the ground. Over-watering of landscape areas should be avoided. Due to the low R-values, wet subgrade conditions could significantly reduce the life of the pavement. Therefore, it is imperative that sübgrade materials are not allowed to become wet or saturated or allow water to flow into trenches or behind curbs. OTHER DESIGN PROFESSIONALS/CONSULTANTS The design civil engineer shall review the recommendations provided herein, incorporate those recommendations into their plans, and by explicit reference, make this report part of their project plans. LIMITATIONS The materials encountered on the project site and utilized for our analysis are believed representative of the area; however, soil and bedrock materials vary in character between excavations and natural outcrops or conditions exposed during mass grading. Site conditions may vary due to seasonal changes or other factors. Inasmuch as our study is based upon our review and engineering analyses and laboratory data, the conclusions and recommendations are professional opinions. These opinions have been derived in accordance with current standards of practice, and no warranty is express or implied. Standards of practice are subject to change with time. GSI assumes no responsibility or liability for work or testing performed by others, or their inaction, or Brookfield San Diego Builders, Inc. W.O. 5949-E-SC Portion of Planning Area 16, Robertson Ranch March 16, 2011 FiIe:e:\wp9\59005949e.pdr4 Page 5 GeoSoils, Inc. work performed when GSI is not requested to be onsite, to evaluate if our recommendations have been properly implemented. Use of this report constitutes an agreement and consent by the user to all the limitations outlined above, notwithstanding any other agreements that may be in place. In addition, this report may be subject to review by the controlling authorities. The opportunity to be of service is greatly appreciated. If you have any questions, please do not hesitate to call our office. Respectfully submitted GeoSoils, Inc. i3c -4 Certfd ) \ 's, E n g In. a cr i 'lei ?o~bert G. Crisman \'\G ''OFCp / Engineering Geologist, EG-493( Exp. bli ,4ndrew T. Guatelli Geotechnical Engineer, GE 2320 RGC/ATG/JPF/jh Attachments: Figures 1 through 3 - A-value Test Results Appendix - References Distribution: (4) Addressee Brookfield San Diego Builders, Inc. W.O. 5949-E-SC Portion of Planning Area 16, Robertson Ranch March 16, 2011 Fi1e:e:\wp9\5900\5949e.pdr4 Page 6 CeoSoils, Inc. Traffic index, assumed 5.0 Gravel equivalent factor, assumed 1.25 Expansion, stability equilibrium 0.93 R-Value by expansion 27 R-Value by exudation 13 R-Value at equilibrium 13 Expansion, Stability Equilibrium 2.00 1.50 .0 Ca U) .0 (0 1.00 0.50 0.001/1111 I 1 11 I'll I I 1 1-4 0.00 0.50 1.00 1.50 2.00 Cover Thickness by Expansion Pressure (ft) TEST SPECIMEN A B C D Compactor air pressure PSI 350 250 150 Water added % 3.7 5.2 6.2 Moisture at compaction 13.0 14.5 15.5 Height of sample IN 2.48 2.53 2.57 Dry density PCF 121.2 117.7 .114.1 R-Value by exudation 28 18 11 R-Value by exudation, corrected 28 18 11 Exudation pressure PSI 595 4261 256 Stability thickness FT 0.92 1.051 1.14 Expansion pressure thickness FT 1.00 0.55 0.10 DESIGN CALCULATION DATA SAMPLE INFORMATION GeoSoils, Inc. ç 5741 Palmer Way @40 $i. Carlsbad, CA 92008 Telephone: (760) 438-3155 Fax: (760) 931-0915 'R -VALUE TEST RESULTS Project: BROOKFIELD Number 5949-E-SC Date: Feb-il Figure: 1 TEST SPECIMEN A Compactor air pressure PSI 350 300 240 Water added % 2.7 3.7 4.7 Moisture at compaction 12.0 13.0 14.0 Height of sample IN 2.43 2.43 2.49 Dry density PCF 122.3 119.6 116.0 R-Value by exudation 27 16 13 R-Value by exudation, corrected 25 15 13 Exudation pressure Psi 466 336 256 Stability thickness I FT 1 0.931 1.0131 1.11 Expansion pressure thickness I FT 1 0.331 0.201 0.07 DESIGN CALCULATION DATA Traffic index, assumed 5.0 Gravel equivalent factor, assumed 1.25 Expansion, stability equilibrium 0 R-Value by expansion NA R-Value by exudation 14 1 111-Value at equilibrium 14 Expansion, Stability Equilibrium 2.00 '1.50 m (I) >' U) W1.00 0.50 0.00-V ' I I 1 I 1 1 I I I I 0.00 0.50 1.00 1.50 2.00 Cover Thickness by Expansion Pressure (ft) SAMPLE INFORMATION Sample Location: Cascade St 10+75 Sample Description: Yellow Brown Clayey Sand Notes: 0% Retained on 3/4 inch sieve In GeoSoils, Inc. (-'••c? 5741 Palmer Way Carlsbad, CA 92008 "-• '-". Telephone: (760) 438-3155 Fax: (760) 931-0915 R - VALUE TEST RESULTS Project: BROOKFIELD Number: 5949-E-SC Date: Mar-li Figure: 2 TEST SPECIMEN A B C D Compactor air pressure PSI 350 290 230 Water added 3.2 3.7 4.2 Moisture at compaction % 12.0 12.5 13.0 Height of sample IN 2.44 2.52 2.59 Dry density PCF 121.8 117.2 114.1 R-Value by exudation 28 18 10 R-Value by exudation, corrected 26 18 10 Exudation pressure PSI 415 320 225 Stability thickness I FT 1 0.921 1.051 1.15 Expansion pressure thickness I FT 1 0.001 0.001 0.00 DESIGN CALCULATION DATA. Traffic index, assumed 5.0 Gravel equivalent factor, assumed 1.25 Expansion, stability equilibrium 0 R.-Value by expansion NA R-Value by exudation 17 R-Value at equilibrium 17 Expansion, Stability Equilibrium 2.00 1.50 U, (1)1.00 I II illII II I I I III 0.00 0.50 1.00 1.50 2.00 Cover Thickness by Expansion Pressure (ft) SAMPLE INFORMATION Sample Location: Northfork Av. 16+50 Sample Description: Yellow Brown Clayey Sand Notes: 0% Retained on 3/4 inch sieve Test Method: -- Cal-Trans Test 301 GeoSoils, Inc. R - VALUE TEST RESULTS 5741 Palmer Way Project: BROOKFIELD Carlsbad, CA 92008 Telephone: (760) 438-3155 Number: 5949-E-SC Fax: (760) 931-0915 Date: Mar-Il Figure: 3 APPENDIX REFERENCES California Department of Transportation, 2006, Caltrans, Standard specifications, May printing. Carlsbad, City of, 1993, Standards for design and construction of public works improvements in the City of Carlsbad. GeoSoils, Inc., 2010, Supplemental. pavement design report, Wind Trail Way (Stations 1 6 to 1 8) ,Alander Court (Stations 1 2 to 1 9+21 and Cascade Street (Stations 12 +25 to 15), Portion of Planning Area 16 of Robertson Ranch, Carlsbad, San Diego County, California, W.O. 5949-E-SC, dated January 13. 2009, Pavement design report, Wind Trail Way (Stations 16 to 18 +76 ), Alander Court (Stations 12+00 to 19+20 and Cascade Street (Stations 12 +25 to 15 +40 ), portion of Planning Area 16 of Robertson Ranch, Carlsbad, San Diego County, California, W.O. 5949-E-SC, dated December 2. NEWCON90, 1991 Computer program for the determination of asphalt pavement sections, dated April 30. O'Day Consultants, 2006, Improvement plans for: Robertson Ranch East Village, City of Carlsbad, Project no: C.T. 02-16, Drawing no. 433-6, dated December 29. State of California, Department of Transportation, 2009, Guide for designing subgrade enhancement geotextiles, dated April 28. 2008, Highway design manual of instructions, dated July 1. GeoSoils, Inc.