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HomeMy WebLinkAboutCT 04-26; ROBERTSON RANCH EAST VILLAGE PA 16, 17, & 18; PAVEMENT DESIGN REPORT WIND TRAIL WAY; 2009-12-02-" Geotechnical S Geologic •Coástal • Environmental 5741 Palmer Way : Carlsbad, California 92010 • (760) 4383155 FAX (760) 931-0915 December 2, 2009 ____..W.o. 5949-E-SC rwE:vET Brookfield San Diego Builders, Inc. I 12865 Pointe Del Mar Suite 200 Del Mar, California 92014 DEC 11 2009 Attention: Mr' McDonnell Subject Pavement Design Report, Wind Trail Way (Stations 16 161 to 18 116 ), Alander Court (Stations 12to 19), and Cascade Street (Stations 12to 15), Portion .ófPlanning Area 16 of Robertson Ranch, Carlsbad, San Diego County, California Dear'Mr. McDonnell: In accordance with yourrequest, GeoSoils, Inc; (GSl) has prepared preliminary design and construction recommendations forasphaltáoncretë (AC) pavement at the subject site. The scope of services provided in preparation of this report include aréview of the referenced reports and documents (see the Appéndix),anevaluation of the pavement section for the subject area,-and preparation of this report. Pavement section evaluation was based on traffic index (TI) values provided by (O'Day Consultants, personal communications). 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 table)i 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. ASPHALT CONCRETE PAVEMENT Structural Section Traffic Indices (TI) were provided by the project civil engineer (O'Day Consultants, personal communication) as 5.0 for the subject traffic areas. R-values (see attached Figures 1 through 4) ranging from 5 to 16 wee obtained for representative subgrade soils onsite and used in pavement design. The recommended pavement sections are provided in general accordance with the City guidelines (City of Carlsbad, 1993) are presented in the following table: APPROXIMATE TRAFFIC AREA TRAFFlC.: INDEX' SLJBGRADE A.C. THICKNESS AGGREGATE BASETHICKNESS13 ER-VALUE (lnches)2 (unhes) 'Wind Trail Way, Stations 16 to ' 5.0 ' (<5 ' 4.0 8.5(2) 18 (Sample obtained from Station 1 Alander Court, Stations 12 to 5.0 4.0 7.0 19 (Samples obtained from Stations 14 and 17) Cascade Street, Stations 12 to 5.0 16 4.0 6.0 15 (Sample obtained from Station 13 Per O'Day Consultants, (Improvement plans) Exceeds City minimum, design per State of California (2006) Denotes Class 2 Aggregate Base R >78, SE >25) 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. It should be noted that subgrade lime treatment was previously waived by the City for the Construction of pavement in the Calavera Hills/Robertson Ranch area (GSI; 2007a, 2007b, 2007c, 2004a, 2004b, and 2004c). It is therefore anticipated that lime stabilization will not be performed for the current road construction. However, due to the low R-values (5 to 16), wet subgrade conditions could significantly reduce the life of the placement. It is imperative that subgrade materials are not allowed to become wet or saturated. 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, Brookfield San Diego Builders, Inc. W.O. 5949-E-SC Portion of Planning Area 16, Robertson Ranch December 2, 2009 File:e:\wp9\5900\5949e.pdr Page 2 GeoSoils, Inc. 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 the increased potential for distress from overuse 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. AGSI 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. Brookfield San Diego Builders, Inc. W.O. 5949-E-SC Portion of Planning Area 16, Robertson Ranch December 2, 2009 Fi1e:e:\wp9\5900\5949e.pdr Page 3 GeoSoils, Inc. Paving Prime coat may be omitted if all of the following conditions are met: The asphalt pavement layer is placed within two weeks of completion of base and/or subbase course. 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 soil engineer. Drainage Positive drainage shall be provided for 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. 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. Brookfield San Diego Builders, Inc. W.O. 5949-E-SC Portion of Planning Area 16, Robertson Ranch December 2, 2009 Fi1e:e:\wp9\5900\5949e.pdr Page 4 GeoSoils,' Inc. 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 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. No. 1934 Certified ) Tiieering I Gjeoiogis Robert G. Crisman Engineering Geologist, 4X ndrew T Geotechni RGC/ATG/J PF/j h Attachments: Figures 1 through 4 - R-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 December 2, 2009 File:e:\wp9\5900\5949e.pdr Page 5 GeoSoils, Inc. TT QD('IMPd A R C D Compactor air pressure PSI 170 50 Water added % 3.8 8.1 Moisture at compaction % 18.1 23.0 Height of sample IN 2.52 2.65 Dry density PCF 109.2 99.5 R-Value by exudation 10 4 R-Value by exudation, corrected 10 4 Exudation pressure PSI 784 424 Stability thickness FT 1.151 1.23 Expansion pressure thickness I FT 1 1.401 0.10 DESIGN CALCULATION DATA Traffic index, assumed 5.0 Gravel equivalent factor, assumed 1.25 Expansion, stability equilibrium 1.18 R-Value by expansion 8 R-Value by exudation <5 R-Value at equilibrium <5* * Soil pressed out of bottom of mold, stopped test. Expansion, Stability Equilibrium I I I I I I I I I I I I 1,1 '1.50 .0 19 cn -o (4, 01.00 0.5O 0.00 K i I I I I I 0.00 0.50 1.00 1.50 2.00 Cover Thickness by Expansion Pressure (ft) SAMPLE INFORMATION Sample Location: Wind Trail 16+60-18+70 Sample Description: Gray Brown Clay Notes: FROM 18+00 0% Retained on 3/4 inch sieve Test Method: Cal-Trans Test 301 R-Value By Exudation 80 - 70 60 50 - CD 40 EZ 30 -- 20 - 10 -z 800 700 600 500 400 300 200 100 0 Exudation Pressure (psi) GeoSoils, Inc. ,s 5741 Palmer Way Carlsbad, CA 92008 '• ----' Telephone: (760) 438-3155 Fax: (760) 931-0915 R - VALUE TEST RESULTS Number: 5949-E-SC Date: Dec-09 Figure 1 TEST SPECIMEN A B C D Compactor air pressure PSI 330 230 170 Water added % 2.7 3.6 4.7 Moisture at compaction % 12.3 13.2 14.5 Height of sample IN 2.4 2.48 2.54 Dry density PCF 122.6 119.7 116.4 R-Value by exudation 26 15 11 R-Value by exudation, corrected 24 15 11 Exudation pressure PSI 559 393 283 Stability thickness FT 0.95 1.09 1.14 Expansion pressure thickness I FT 1 1.87 1.201 0.37 DESIGN CALCULATION DATA Traffic index, assumed 5.0 Gravel equivalent factor, assumed 1.25 Expansion, stability equilibrium 1.1 R-Value by expansion 14 R-Value by exudation 11 1 111-Value at equilibrium 11 Expansion, Stability Equilibrium (0 (01.00 0.50 0.00 l' 1 1 1 1 1 1 1 I 1 1 I 1 I 1 1I I 0.00 0.50 1.00 1.50 2.00 Cover Thickness by Expansion Pressure (It) SAMPLE INFORMATION Sample Location: Alander 12+00-15+60 Sample Description: Gray Brown Sandy Clay Notes: FROM 14+36 0% Retained on 3/4 inch sieve Test Method: Cal-Trans Test 301 R-Value By Exudation 80 - 70 60 50 a) 30 IIIII-III 800 700 600 500 400 300 200 100 0 Exudation Pressure (psi) 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: Dec-09 Figure: 2 TEST SPECIMEN A B C D Compactor air pressure PSI 350 150 80 Water added % 0.0 3.4 4.7 Moisture at compaction % 13.3 17.0 18.5 Height of sample IN 2.37 2.5 2.58 Dry density PCF 120.2 112.5 109.1 R-Value by exudation 22 11 7 R-Value by exudation, corrected 21 11 7 Exudation pressure PSI 669 3031 204 Stability thickness FT 1.00 1.14 1.19 Expansion pressure thickness FT 3.67 0.531 0.30 DESIGN CALCULATION DATA Traffic index, assumed 5.0 Gravel equivalent factor, assumed 1.25 Expansion, stability equilibrium 11 R-Value by expansion 14 R-Value by exudation 11 R-Value at equilibrium Ii Expansion, Stability Equilibrium 4.00 . 3.50 .4- '3.00 .0 u,2.50 >. .0 U, n2.00 0 C CS —1.50 1.00 SAMPLE INFORMATION Sample Location: Alander 15+60-19+20 Sample Description: Gray Brown Sandy Clay Notes: FROM 17+60 0% Retained on 3/4 inch sieve Test Method: Cal-Trans Test 301 R-Value By Exudation 80 I I 70 WE 50 a) 40 'I II HEN • 0 I .Ti. i• 800 700 600 500 400 300 200 100 0 Exudation Pressure (psi) GeoSoils, Inc. . 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: Dec-09 Figure: 3 TFST PF(IMFN A B C D Compactor air pressure PSI 350 280 230 Water added 4.8 5.3 5.8 Moisture at compaction % 13.0 13.6 14.2 Height of sample IN 2.5 2.53 2.55 Dry density PCF 121.3 119.3 117.7 R-Value by exudation 22 18 15 R-Value by exudation, corrected 22 18 15 Exudation pressure PSI 448 365 281 Stability thickness I FT 1 1.001 1.051 1.09 Expansion pressure thickness I FT 1 1.401 0.731 0.10 DESIGN CALCULATION DATA Traffic index, assumed 5.0 Gravel equivalent factor, assumed 1.25 Expansion, stability equilibrium 1.03 R-Value by expansion 20 R-Value by exudation 16 R-Value at equilibrium 16 Expansion, Stability Equilibrium 2.00 SAMPLE INFORMATION Sample Location: Cascade 12+25-15+40 Sample Description: Gray Brown Sandy Clay Notes: FROM 13+90 0% Retained on 3/4 inch sieve Test Method: Cal-Trans Test 301 R-Value By Exudation 80- 7.____ .'1.50 .0 C') .0 Cl) U) 1.00 60 50 a) 40 70 30 20 10 CD 0.50 0.00.1/ I I I I I 0.00 0.50 1.00 1.50 2.00 Cover Thickness by Expansion Pressure (ft) o - I 800 700 600 500 400 300 200 100 0 Exudation Pressure (psi) GeoSoils, Inc. ,.. 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: Dec-09 Figure: 4 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., 2008, Memo, Clarification of pavement design report, Glen Avenue, Station 26 to the GuI Du Sac, Robertson Ranch East Village, City of Carlsbad, San Diego County, California, W.O. 5353-B-SC, dated October 31. 2007a, Pavement design report, Improvement of "loop" roads, Wind Trail Way, Glen Avenue, and Hilltop Street, Robertson Ranch East Village, City of Carlsbad, San Diego County, California, W.O. 5384-E-SC, dated October 31. 2007b, Pavement design report, Improvement (widening) of College Boulevard (Stations 103 to 118), and Cannon Road (Stations 127 to 159), City of Carlsbad, San Diego County, California, W.O. 5354-E-SC, dated September 18. 2007c, Review ofR-value data, Improvement (widening) of College Boulevard (Stations 103 to 118+1),and Cannon.Road (Stations 127 to 159), City of Carlsbad, San Diego County, California, W.O. 5354-E-SC, dated September 4. 2004a, Revised pavement design. report, College Boulevard Stations 78 to Reach C, Calavera Hills II, Carlsbad, San Diego County, California, W.O. 4028-E-SC, dated April 19. 2004b, Revised pavement design report, College Boulevard Stations 101 to 1180, Reach B, Calavera Hills II, Carlsbad, San Diego County, California, W.O. 4029-E-SC, dated April 23. 2004c, Third revision of pavement design report, Calavera Hills II, Cannon Road +50 Stations 125 to 164, City of Carlsbad, San Diego County, California, W.O. 4030-E-SC, dated May 14. N EWCON9O, 1991 Computer program for the determination of asphalt pavement sections, version: April 30. State of. California, Department of Transportation, 2006, Highway design manual of instructions, sixth edition, September printing. GeoSolls, Inc.