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HomeMy WebLinkAboutCT 01-04; CALAVERA HILLS VILLAGE U; PAVEMENT DESIGN REPORT; 2004-12-16c_ro.oL - * - Geotechnical • Geologic• Environmental 5741 Palmer Way • Carlsbad California 92008. (760) 438-3155, • FAX (760) 931-0915 Revised December 16, - .. Brookfield Homes V. 12865 Pointe Del Mar, Suite 200 Del Mar, California 92014 -.. . Attention Mr. John Moore Subject Pavement Design Report, Calavera Hills Il, Village U, Carlsbad, San Diego County, California Dear Mr. Moore In accordance with your request, GeoSoils, Inc. (GSI) has prepared design and construction recommendations for asphalt concrete (AC) pavement at the subject site. The. sèope of services provided in preparation of this report included representative sampling of the street subgrade, R-value testing, and engineering analysis of pavement design . . . . 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 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), determined from soils exposed at, or rear, final subgade elevations within the subject 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 NEWCON90 ASPHALT CONCRETE PAVEMENT .... Structural Section .. R-values ranging from 16 to 23 were determined for subgrade soils 6nsite and used in pavement design The recommended pavement sections are presented in the following table tt . . - - . a,' " • • - t AC AGGREGATE BASE TRAFFIC SUBGRADE THICKNESS THICKNESS'2 TRAFFIC AREA INDEX R-VALUE (lnches)(1) (inches) Peninsula Dr. (Sta.10to20 22 5.0 17 4.0 6.0 Peninsula Dr. (Sta. 20 to 5.0 29 4.0 5.0 26-) Inlet Drive (All Stations) 5.0 16 4.0 6.0 FKarst Drive (All Stations) 5.0 16 4.0 6.0 City of Carlsbad minimum Denotes Class 2 Aggregate Base ® >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 are meant as minimums. If thinner or highly variable pavement sections are constructed, increased maintenance and repair may be needed. 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 enclosing planters, sidewalks with thickened edges, etc. If the ADT (average daily traffic) orADTT (average daily truck traffic) increases beyond that intended, as reflected by the traffic index(s) used for design, increased maintenance and repair could be required for the pavement section. 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 surlicial 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 approximately 6 inches, moisture conditioned as necessary, and compacted to 95 percent of the maximum laboratory density, as determined by ASTM Test Designation D-1557. Brookfield Homes W.O. 4067-E-SC Calavera Hills, Village U, Carlsbad Revised December 16, 2004 Fi1e:e:\wp9\4000\4067e.pdr Page 2 GeoSosis, Inc. 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 the "Standard Specifications for Public Works Construction" (green book), 1997 edition, or standard Caltrans Class 2 base rock (minimum R-value = 78). 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. 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 cut-off walls, etc. Brookfield Homes W.O. 4067-E-SC Calavera Hills, Village U, Carlsbad Revised December 16, 2004 Fi1e:e:\wp9\4000\4067e.pdr Page 3 GeoSoils, Inc. David W. Sb Civil Engineer, HUE 47857 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, either express or implied, is given. 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 thi.s 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. Thus, this report brings to completion our scope of services for this portion of the project. - The opportunity to be of service is greatly appreciated. If you have any questions, please do not hesitate to call our office. Respectfully G. GeoSo No. 193 ilsjnc. / I Exp.O(17,j Robert G. Crisman . Engineering Geolog RGC/JPF/DWS/jh Attachments: Figures 1 through 3 - R-value Test Results Appendix - References Distribution: (3) Addressee (1) Jobsite Trailer, Attention: Mr. Adam Vandervort Brookfield Homes W.O. 4067-E-SC Calavera Hills, Village U, Carlsbad Revised December 16, 2004 Fi1e:e:\wp9\4000\4067e.pdr Page 4 GeoSoils, Inc. it APPENDIX S REFERENCES American Public Works Association, 2000, "Greenbook" standard specification for public works construction. 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. S S NEWCON90, 1991 Computer program for the determination of asphalt pavement sections, version: April 30. 5 PAVE, Computer program for the determination of asphalt concrete pavement sections. State of California, Department of Transportation, 1987, Highway design manual of instructions, fourth edition. S S GeoSoils, Inc.