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HomeMy WebLinkAboutCT 00-02; CALAVERA HILLS PHASE 2; SECOND REVISED PAVEMENT DESIGN REPORT; 2004-05-14- c-roOO2- 5:55 Geotechnicàl • Geologic. Environmental 5741 Palmer Way • Carlsbad, California 92008 • (760) 438-3155. • FAX (760) 931-0915 May 14, 2004 5. 5 W.O. 4124-E-SC. . S Calavera Hills II, LLC . S 2727 Hoover Avenue' . National City, California 91950 • . . . Attention Mr. Don Mitchell Subject: Second Revised Pavement Design Report, Calavera Hills II, Carlsbad Village Drive, Stations 472 to City of Carlsbad, San Diego County, California Dear Mr. Mitchell:. In accordance with your request; GeoSoils, Inc. (GSI), has prepared preliminary design - and construction recommendations for asphalt concrete (AC) pavement at the subject site. The scope of services provided in preparation of this report included representative 0 sampling of the street subgrade, A-value testing, and engineering analysis of pavement design 5 . S PAVEMENT DESIGN . .. Pavement section design' was performed in accordance with the California Departmentof 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) determined from soils exposed at, or near, final subgrade elevations within the subject areas. A-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 .5 •' . ASPHALT CONCRETE PAVEMENT .• . . 5 5,. 0 Structural Section An A-value of 25 was determined for subgrade soils onsite and used in pavement design. The recommended pavement sections are presented in the following table S .,. ASPHALT AGGREGATE TRAFFIC ' TRAFFIC SUBGRADE CONCRETE BASE AREA INDEX R-VALUE THICKNESS THICKNESS (2) * S - (Inches) . (Inches) arlsbad Village Drive E 8.5 25 5.0(1) 13.0(1) tations 47 to 54 City minimum Denotes Class 2 Aggregate Base R ?78, SE >25) All pavement installation, including preparation and compactioh 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. 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. If the ADT (average daily traffic) or ADTT (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. • . Subcirade 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 exposed . subgrade shall 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. Calavera Hills II, LLC W.O. 41 24-E-SC' Carlsbad Village Drive, Calavera Hills Il May 14, 2004' FiIe:e:\wp9\4100\4124e.rrpdr Page 2 GeoSoils, 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 .1. 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 hot 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, thickened edges, etc. .. . •. . . . Caiavera Hills ii, LLC . . . .. • . W.O. 4124-E-SC Carlsbad Village Drive, CaiaveraHilis ii . . . May 14, 2004 Ffle:e:\wp9\4100\4124e.rrpdr. . . . • . • Page 3 GeoSoils, Inc. . . 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 cónditionsexposed during mass grading. Site conditions may vary due to seasonal changes or other factors. Inasmuch as our study is based upon our reviewand 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 expressed 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 maybe in place. In addition, this report may be subject to review by the controlling authorities. Calavera Hills II, LLC W.O. 4124-E-SC Carlsbad Village Drive, Calavera Hills II May 14, 2004 FiIe:e:\wp9\4100\4124e.rrpdr - • •. • Page 4 GeoSoils, Inc. . S The opportunity to be of service is sincerely appreciated. If you should have any questions, . please do not hesitate to contact our office. ED Gpo Respectfully G. GeoSoils, Inc 1934 % \ Reviewed by:ACE 4737 1-40, 00 C \AIL Robert G. Crisman. David W. Skelly OF C Engineering Geologist, . . . . . Civil Engineer, R 47857 RGC/JPF/DWS/Jk Attachment Appendix - References Distribution: (1) Addressee (2) Jobsite, Attention: Mr. Tom LaMarcà (2) City of Carlsbad, Attention Mr. Joe McMahon (1 wet signed) Caiavera Hills Ii, LLC . . . . . . W.O. 4124-E-SC Carlsbad Village Drive, Calavera Hills ii . May. 14, 2004 FiIe:e:\wp9\4100\4124e.rrpdr . . . .. . . . . .. Page 5 GeoSoiIs Inc. . . APPENDIX REFERENCES American Public Works Association, 2000, "Greenbook" standard specification for public works construction; California Department of Transportation, 1995, Caltrans, Standard specifications, July printing. .1 Carlsbad, City of, 1993, Standards for design, and construction of public works improvements in the City of Carlsbad. NEWCON90,.1991 Computer program for the determination of asphalt pavement sections, version: April 30. • • 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 I T7 -- GeotechnicaI 'Geologic. Environmental 5741 Palmer Way • Carlsbad, California 92008 • (760) 438-3155 • FAX (760) 931-0915 May 14, 2004 W.O. 4125-E-SC Calavera Hills II, LLC 2727 Hoover Avenue National City, California 91950 Attention: Mr. Don Mitchell Subject: Second Revised Pavement Design Report, Calavera Hills ll,.Harwich Drive (Stations 25 to 28 2), and Glasgow Drive (Stations 53t58), City of Carlsbad, San Diego County, California Dear Mr. Mitchell: In accordance with your request, GeoSoils, Inc. (GSI), has prepared preliminary design and construction recommendations for asphalt concrete (AC) pavement at the subject site. The scope 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) determined from soils exposed at, or near, final subgrade 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 withthe computer software programs PAVE and NEWCON90. ASPHALT CONCRETE PAVEMENT Structural Section R-values of 9 and 10 were determined for subgrade soils onsite and used in pavement design. The recommended pavement sections are presented in the following table: ASPHALT AGGREGATE TRAFFIC TRAFFIC SUBGRAD.E CONCRETE BASE. AREA . INpEX R-VALUE.. THICKNESS THICKNESS('-2)- (inches)(') (Inches;)* Harwich Drive 5.0 9 5.0 11.0 Stations 25+37 to 28+18 Glasgow Drive 5.0 10 5.0 11.0 Stations 53 6- to 58+2 City minimum, per City of Carlsbad Engineering Department 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 the City. It shall be noted that the City engineering department has waived subgrade testing for lime treatment in lieu of the recommended sections presented above. 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. If the ADT. (average daily traffic) or ADTT (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 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 Calavera Hills II, LLC . . W.O. 4125-E-SC Harwich Dr. and Glasgow Dr., Calavera Hills II . May 14, 2004 FiIe:e:\wp9\4100\4125e.rrpdr Page 2 In 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 OCk 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: 1: 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 Calavera Hills II, LLC W.O. 4125-E-SC Harwich Dr. and Glasgow Dr., Calavera Hills II May 14, 2004 FiIe:e:\wp9\4100\4125e.rrpdr. Page 3 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.. 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 expressed 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. Calavera Hills II, LLC W.O. 41 25-E-SC Harwich Dr. and Glasgow Dr., Calavera Hills II May 14, 2004 FiIe:e:\wp9\4100\4125e.rrpdr Page 4 Gaimsells. Enc. The opportunity to be of service is greatly appreciated. If you have any questions, please do not hesitate to call our e. IE o r Respectfully su bm GeoSoils, Inc. I (1,I C Robert G. Crisman -...-..- Engineering Geologist, CEG 1934 RGC/JPF/DWS/jk Reviewed by: David W. Skelly Civil Engineer, RCE 4 /.\..) c,,\ J r'L A77 i4Cr.v,J, l-J Oj C Attachment: Appendix - References Distribution: (1) Addressee (2) Jobsite, Attention: Mr. Tom LaMarca (2) City of Carlsbad, Attention: Mr. Joe McMahon (1 wet signed) Calavera Hills II, LLC Harwich Dr. and Glasgow Dr., Calavera Hills II File:e:\wp9\4100\4125e.rrpdr W.O. 4125-E-SC May 14, 2004 Page 5 APPENDIX 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. NEWCON90, 1991, Computer program for the determination of asphalt pavement • sections, version: April 30. 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. • irE; S Geotechnucal • Geologic • Environmental 5741 Palmer Way • Carlsbad California 92008 • (760) 43&-3155 • FAX (760) 931-0915 May 14, 2004 W.O.4126-E-SC Calavera Hills II, LLC .. - 2727 Hoover Avenue 77 National City, California 91950 Attention Mr. Don Mitchell Subject: Second Revised Pavement Design Report, Calavera Hills II, Tamarack : Avenue, Stations 67 to 74i, City of Carlsbad, San Diego County, California Dear Mr. Mitchell In accordance with your request, GeoSoils, Inc. (GSI), has prepared preliminary design and construction recommendations for asphalt concrete (AC) pavement at the subject site. The scope 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), determined from soils exposed at, - or near, final subgrade 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-vàlues of 17 and 19 were determined for subgrade soils onsite and used in pavement design. Based on a curb to curb distance of 40 feet, and a right of way width of 60 feet, '; -'• : I , ASPHALT' 'AGGREGATE, 4 "-'TRAFFIC TRAFFIC 3SUBGRADE CONCRETE BASE f AREA I INDEX ?'R-VALUE :THICKNESS ? THICKNESS2 4. I 1 Vig Tamarack Avenue, 5.0 19 4.0 5.0 Stations 67 to 71 +00 Tamarack Avenue 5.0 17 4.0 6.0' Stations 71 22 to74 1 City minimum " Denotes Class 2 Aggregate Base ® >78, SE >25) . S the traffic index to be used in pavement design is 5.0 (local street) per the city. The actual traffic index shall be verified by theproject civil engineer and the appropriate section constructed. The recommended pavement sections for the traffic index is presented in the following table: . . ". 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. 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. If the ADT (average daily traffic) or ADTT (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 changestshall be properly transitioned. If adverse conditions are encountered during the preparation of subgradé materials, special construction methods may need to be employed. A GSl representative shall be present for the preparation of subgrade, base rock' and asphalt concrete. • ' Calavera Hills II, LLC - • W.O. 41 26-E-SC Tamarack Avenue, Calavera Hills II -' - • May 14, 2004 Fi1e:e:\wp9\4100\4126e2,rrpdr - - Page - . GeoSoils, Inc. 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 dèterminéd 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 RvaluO = 78). Pavinci , 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. 3.' Construction is completed during the dry season of May through October. 4 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, Js 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. • • : 5. '- • Calavera Hills ii, LLC W.O. 4126-E-SC Tamarack Avenue, Calavira Hills II May 14, 2004 File:e:\wp9\4100\4126e2.rrpdr • Page GeoSoils, Inc. . Drainage S - 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. 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. expressed or implied. Standards of practice are subject to change with.timë'. 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 maybe in place. In addition, this report may be subject to. review by the controlling authorities. . . Calavera Hills II, LLC . . . W.O: 41 26-E-SC Tamarack Avenue, Calavera Hills II • . May 14, 2004 File: e:\wp9\4100\4126e2.rrpdr Page 4 S. GeoSoils, Inc. . . . . . The opportunity to be of service is greatly appreciated.. If you have any questions, please do not hesitate to call our.office. Respectfully submi GeoSotis, Inc ' Reviewed by ... r Eyp Robert David W. S ell Engineering Geologist, 4 Civil Engineer, RCE 857 c:. RGC/JPF/DWS/jk • •• Attachment: Appendix - References •. • Distribution: (1) Addressee S . • (2) Jobsite, Attention: Mr. Tom LaMarca S • (2) City of Carlsbad, Attention Mr. Joe McMahon (1 wet signed) / Calavera Hills ii, LLC • S • W.O. 4126ES0 Tamarack Avenue, Calavera Hills II • • May 14, 2004 FUe:e:\wp9\4100\4126e2.rrpdr S : S Page 5 GeoSoits, Inc. S APPENDIX. 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. . . . . . NEWCON90, 1991 Computer program forthe determination of asphalt pavement sections, version: April 30. . . . . . . . . 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. . GeoSoils, Inc. Th . Geoteáhnical • Geologic. Environmental 5741 Palmer Way • 'Carlsbad, California 92008 •. (760) 438-3155 • FAX (760) 931-0915 May 14, 2004 W.O.4126-E-SC Calavera Hills II, LLC , 2727 Hoover Avenue / National City, California 91950 1- Attention Mr. Don Mitchell - 2 Subject: Second Revised Pavement Design Report, Calavera Hills ll,'Glasgow Street, -:. Stations 40Z to 46i, City of Carlsbad, San Diego County, California Dear Mr.'Mitchell: In accordance with your request, GeoSoils, Inc. (GSl), has prepared preliminary design And construction recommendations for asphalt concrete (AC) pavement atthe subject site. The scope of services provided in preparation of this report included representative sampling of the street subgrade, A-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) determined from soils exposed at, or near, final subgrade elevations within the subject areas. A-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 - ' • • An R-valueof 17 was determined for subgrade soils onsite and used in pavement design. The recommended pavement sections are presented in the following table: • ' S • ASPHALT AGGREGATE' TRAFFIC TRAFFIC SUBGRADE CONCRETE' BASE , AREA, INDEX ,R-VALUE ' THICKNESS' THICKNESS(2) (inches)(1) ". (inches) Glasgow Drive 5.0 ' .17 ' 4.0 ' 6.0' Stations 40 to 46 City 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 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. 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. If the ADI (average daily traffic) or ADTT (average daily truck traffic) increases beyond that intended, as reflected by the traffic index(s) used for design, increased mainteñan'ce 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 isto 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 0 • '0 Calavera Hills ii, LLC ' ' ' ' W.O. 4126-E-SC Glasgow Drive, Caiavera Hills ii ' • ' ' ' ' ' ' May 14, 2004 Fi1e:e:\wp9\4100\4126e.rrpdr 0 ' ' ' 0 • , ' Page 2 GeoSoils, Inc. ' ' Deleterious material, excessively wet or dry pockets, concentrated zones of oversized rock fragments, and any other unsuitable materials encountered during grading shall be V 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 V observed by the project soil engineer and/or his representative. V V Base Rock V V V V V 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). V V Paving Prime coat may be omitted if all of the following conditions are met: V 1. The asphalt pavement layer is' placed within two weeks of completion of base and/or subbase course. V V 2. Traffic is not routed over completed base before paving. 3. 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. Drainaáe 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 beV taken to Vminimize the potential for water to enter the pavement section, such as cut-off walls. V Calavera Hills II, LLC • V • W.O. 4126-E-SC Glasgow Drive, Calavera Hills II May 14, 2004 FiIe:e:\wp9\4100\4126e.rrpdr Page .3 V V V V GeoSoils, me. V • 1 S . 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 . H 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 expressed or implied. Standards of p.ractice 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 GSl 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. Calavera Hills II, LLC . . .. S . S W.O. 4126-E-SC Glasgow Drive, Cal avera Hills II - . 5 .. . , May 14, 2004 Fi1e:e:\wp9\4100\4126e.rrpdr- . . . ... - Page 4 GeoSoils, Inc . . 5. . The opportunity to be of service is sincerely appreciated. If you should have any questions, please do not hesitate to contact our office. Respectfullysubied vi. -' GeoSoils, In Reviewed by '• ____ OF GAO~ Robert G. David W Skelly Engineering Geolo _ 934 Civil Engineer, RCE 47857 RGC/J PF/D WS/j k Attachment: Appendix - References Distribution: (1) Addressee (2) Jobsite, Attention: Mr. Tom LaMarca (2) City of Carlsbad, Attention: Mr. Joe McMahon (1 wet signed) Calavera Hills II, LLC W.O. 4126-E-SC Glasgow Drive, Calavera Hills II M 14 2004 May FiIe:e:\wp9\4100\4126e.rrpdr e 5 Page GeoSoils, Inc. S . APPENDIX : REFERENCES - American Public Works Association; 2000', "Gréenbook" 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. - • ' • . NEWCON90, 1991 Computer program for the determination of asphalt pavement sections, ' version: April30. . • S S S. • PAVE, Computer program for the determination of asphalt concrete pavementsections. S State of California., Department of Transportation, 1987, Highway design manual of S • • instructions, fourth edition. S , S I c-roo--o'2. FIELD TESTING REPORT W.O. '-j/ Lj - S DATE 9-i 3 3 NAME 4J f HOURS( CLIENT fl'\L4i I I! I VN TRACT LOCATION_(2rS 6A SUPT. -co&'t L CONTRACTOR EQUIPMENT _2,c;a — C tc(Ar \JL D( TEST NO. LOCATION ELEV. OR DEPTH MOISTURE CONTENT % DRY DENSITY P.C.F. % RELATIVE COMPACTION TEST TYPE SOIL TYPE 1/ LI It ci_ j7 1/ 4Y1 52. L7 It-I S'/• u - A -,tt 1',L'_C 1iZc) AZ COMMENTS: RQ i ) fOQ iw) V\(4t' \LI() / cCJL kC r3A- OLALV) - -•' ±_ /c _/4tt GeoSoils, Inc. A&I _A-iitL qç '7L_2(I BY: PAGE ) OF ) E:/wp/forms/fieldtst.wpd