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HomeMy WebLinkAboutCT 03-13; BLACK RAIL RIDGE; PAVEMENT DESIGN REPORT TRITON STREET; 2005-07-26I LIE, LOY Geotechnical Geologic Environmental 5741 Palmer Way. Carlsbad, California 92008 • (760) 438-3155 • FAX (760) 931-0915 July 26, 2005 W.O. 4760-E-SC Mayfair Homes, Inc. . 3443 Camino Del Rio South, Suite 312 San Diego, California 92108 Attention: Mr. Brian Sorokin . Subject: Pavement Design Report, Triton Street and Blackrail Road Frontage Adjacent to the Blackrâil Ridge Subdivision, CT.03-13, Carlsbad, San Diego County, California :. Dear Mr. Sorokin:. . .. In accordance with your request, GeoSoils, Inc. (GSI) has prepared preliminary design and construction récom men dations.foràsphalt concrete (AC) pavementatthe subject site. The scope of services provided in preparation of this report included sampling of soils in the street right-of-way, R-value,testing, and engineering analysis of pavement design..r This report is subject to the review Of the controlling authorities. . . PAVEMENT DESIGN . Pavement section design was performed in accordance with the California Department of Transportation (Caltrans) Highway Design Manual of instructions, and the City of Carlsbad Criter(see the Appendix). Pavement sections for AC are based on the aforementioned criteria-and resistance value (R-value) data (see the attached Figures 1 and 2), determined from soils exposed at, or near, final subgrade elevations within thesubject areas. R-value testing was performed in accordance with the latest revisions to the Department of Transportation, State of California, Material & Research Test Method No. 301. Pavement design was aided with the computer software programs PAVE and NEWCON9O. Traffic indices were provided by the Client and/or their representatives. . . ASPHALT CONCRETE PAVEMENT Structural Section R-values of 19 and 43 were determined for subgrade soils onsite and used in pavement design. The recommended pavement sections are presented in the following table: • A.c AGGREGATE TRAFFIC RA DE, THICKNESS BASE THICKNESS'21 • TRAFFIC AREA . INDEX R-VALUE (INCHES)" (INCHES) Triton Street 5.0 19 4.0 5.0 Blackrail Road 6.0 43 4.0 6.0 (1) City of Carlsbad minimum• ()'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 City. 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 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 should be properly transition ed. If adverse conditions are encountered during the preparation of subgrade materials, special construction methods may need to be employed. A GSI representative should be present for the preparation of subgrade, base rock, and asphalt concrete. Mayfair Homes W.O. 4760-E-SC Blackrail Ridge, Carlsbad July 26, 2005 Fi1e:e:\wp9\4700\4760e.pdr1 Page 2 GeoSoils, Inc. Subgrade Within street arid parking areas, all surficial deposits of loose soil material should 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-1 557. 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 should 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 to the "Standard Specifications for Public Works Construction" (green book) 1997 edition or standard Caltrans Class 2 base rock (minimum fl-value = 78) 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 2 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 wetseason 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. Mayfair Homes W.O. 4760-E-SC Biackraii Ridge, Carlsbad July 26, 2005 Fi1e:e:\wp94700\4760e.pdr1 : Page 3 GeoSoils, Inc. Drainage Positive drainage shall be provided fOr all surface water to drain towards 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. If planters or landscaping are adjacent to paved areas, measures shall be taken to minimize the potential for water to enter the pavement section, such as thickened edges, enclosed planters, etc. LIMITATIONS The materials encountered on the project site and utilized in our laboratory study are believed to be representative of the total area. However, variations from the anticipated conditions and actual field conditions should be expected Test excavations are reflective of the soil and rock materials only at the specific location explored. Site conditions may vary due to seasonal changes or other factors. Since our study is based on the earth materials obtained, in the field onsite, selective laboratory testing and engineering analyses, the conclusions and recommendations are professional opinions based upon those parameters. These opinions have been derived in accordance with the current standards of practice and no warranty is expressed or implied Standards of practice are subject to change in time Overall, the enclosed results represent our professional opinions and evaluations which were performed within the constraints of a budget GSI assumes no responsibility or, liability for work or testing performed by others Mayfair Homes Biackrail Ridge, Carlsbad FiIe:e:\wp9\47004760e.pdr1 W.O. 4760-E-SC July 26, 2005 Page 4 GeoSoils, Inc. , , The opportunity to be of service is sincerely áppreciatéd. If you should have any questions, please do not hesitate to contact our office. 0.1934 V dertifled ring cc RCE 478z;)7' SO p Geologist _ Robert G. Crisman OF cM David W. Skelly 4 CivtS.. Engineering Geologist, CEG 1934 Civil Engineer, RCE 4 0.CM- RGC/DWS/JPF/jk Attachments:. Figures 1 and 2 - R-value Test Results Appendix - References • Distribution: (4) Addressee I • • :. Mayfair Homes W.O. 4760-E-SC Blackrail Ridge, Carlsbad • . July 26, 2005 Fie:e:\wp947004760e.pdr1 Page 5 GeoSosis, Inc. TEST SPECIMAN A B C D Compactor air pressure PSI 320 260 160 Water added % 2.8 3.5 4.1 Moisture at compaction % 10.2 11.0 11.7 Height of sample IN 2.46 2.48 2.49 Dry density PCF 124.2 123.1 122.7 R-Value by exudation 33 21 16 R-Value by exudation, corrected 33 21 16 Exudation pressure PSI 569 348 257 Stability thickness FT 0.86 1.01 1.08 Expansion pressure thickness FT 0.83 0.401 0.13 DESIGN CALCULATION DATA Traffic index, assumed 5.0 Gravel equivalent factor, assumed 1.25 Expansion, stability equilibrium 0.85 R-Value by expansion 34 R-Value by exudation 19 R-Value at equilibrium 19 Expansion, Stability Equilibrium 2.00 SAMPLE INFORMATION Sample Location: Triton Street Sample Description: Red Brown Clayey Sand Notes: 0% Retained on 3/4 inch sieve Test Method: Cal-Trans Test 301 R-Value By Exudation 80 70 60 U, (01.00 0.50 0.00 1,III I II 11 1 11 Ii 0.00 0.50 1.00 1.50 2.00 Cover Thickness by Expansion Pressure (ft) 50 C) 40 CC > ck: 30 20 10 0 800 700 600 500 400 300 200 100 . 0 Exudation Pressure (psi) GeoSoils, Inc. 5741 Palmer Way GI$J. Carlsbad, CA 92008 Telephone: (760) 438-3155 Fax: (7 60) 931-0915 R - VALUE TEST RESULTS Project: MAYFAIR HOMES Number: 4760-E-SC Date: May-05 Figure: 1 TEST SPECIMAN A B C D Compactor air pressure PSI 350 350 170 Water added % 2.2 2.2 3.3 Moisture at compaction % 10.5 10.5 11.7 Height of sample IN 2.48 2.48 2.5 Dry density PCF 123.3 124.9 123.4 R-Value by exudation 68 53 21 R-Value by exudation, corrected 68 53 21 Exudation pressure PSI 468 349 198 Stability thickness FT 0.41 0.601 1.01 Expansion pressure thickness FT 0.83 0.331 0.10 DESIGN CALCULATION DATA Traffic index, assumed 5.0 Gravel equivalent factor; assumed 1.25 Expansion, stability equilibrium 0.52 R-Value by expansion 59 R-Value by exudation 43 R-Value at equilibrium 43 SAMPLE INFORMATION Sample Location: Black Rail Road Sample Description: Yellow Brown Silty Sand Notes: 0% Retained on 3/4 inch sieve Test Method: Cal-Trans Test 301 R-Value By Exudation 2.00 .'150 .0 to Expansion, Stability Equilibrium 80 70 60 50 40 > 30 20 10 I I liii! liii 0 -! I I 0.00 0.50 1.00 1.50 2.00 800 700 600 500 400 300 200 100 0 Cover Thickness by Expansion Pressure (ft) Exudation Pressure (psi) GeoSoils; Inc. 5741 Palmer Way 4qSJ I4J . Carlsbad CA 92008 . Telephone: (760) 438-3155 Fax: (760) 931-0915 - VALUE TEST RESULTS Project: MAYFAIR HOMES Number: 4760-E-SC Date: Jul-05 Figure: 2 APPENDIX REFERENCES California Department of Transportation, 1995, Caltrans, standard specifications, July printing Carlsbad, City of, 1993, Standards for design and construction of public works improvements in the City of Carlsbad. NEWCON90, 1991 Computer program forthe determination df asphalt pavement sections, version: April 30. -. PAVE, Computer program for the determination of asphalt concrete pavement sections State of California, Department of Transportation, 1987,1 Highway design manual of instructions, fourth edition I GeoSoils, Inc.