Loading...
HomeMy WebLinkAboutBUCKING HORSE FILING ONE - Filed GC-GENERAL CORRESPONDENCE - 2014-07-17August 2, 2013 4 Bellisimo, Inc. EARTH ENGINEERING 3702 Manhattan Ave Suite 201 CONSULTANTS, LLC Fort Collins, Colorado 80526 Attn: Mr. Gino Campana (gcampana(&,bellisimoinc.com) Re: Pavement Thickness Design Report Bucking Horse Pavements — Balance of Filing 1 (Phase III) and Drake Road Widening City of Fort Collins, Colorado EEC Project No. 1124098P Mr. Campana: Earth Engineering Consultants, LLC (EEC) personnel submitted a subgrade evaluation report to you for selected interior roadways within the Bucking Horse Phase Filing No. 1 — Phase III portion of the residential development, along with the widening/Right turn lane portion of Drake Road east of Timberline Road, in east Fort Collins, Colorado on July 31, 2013 and August 1, 2013 respectively. Based on those two (2) separate reports, (i.e., the interior roadways within the balance of Filing No. 1 and Drake Road widening), the City of Fort Collins' Engineering Department has provided estimated traffic loading criteria, expressed as 18-kip equivalent daily load axles (EDLA), for the development roadways/streets, which have been prepared to date. Pavement section recommendations are provided in this report based on the traffic information provided by the City of Fort Collins Engineering Department and the subgrade field and laboratory test results previously completed by EEC. The evaluated roadways herein include the widening/right turn lane improvements along Drake Road, all or portions of Blue Yonder Way, Yearling Drive, Cutting Horse Drive, and Gooseberry Road, along with the continuation of Sandbur Lane and Bucking Horse Lane from the previous Side Hill Development phase. A Hveem Stabilometer/R-value of 12 was determined for the rough -graded pavement subgrades completed for this portion of the Bucking Horse development. Using the Colorado Department of Transportation (CDOT) and the current Larimer County Urban Area Street Standards (LCUASS) Pavement Design Criteria, an R-value of 12 corresponds to a resilient modulus value of 3803 psi, which was used in the pavement evaluation for the roadways included herein. The American Association of State Highway and Transportation Officials (AASHTO) design guidelines for pavement thicknesses were used to evaluate recommended pavement sections for this 4396 GREENFIELD DRIVE WINDSOR, COLORADO 80550 (970) 545-3908 FAX (970) 663-0282 I , , Page 2 of 2 In addition to the horizontal information, we have also considered the vertical profile of Timberline. There is a decent slope dropping down from the Jessup Farm to the railroad crossing. Locating this private right-in/right-out driveway as far north as possible is intended to avoid any safety concerns. I look forward to getting your feedback. Perhaps this is something that could be discussed at TransCord this week. Please let me know if you have any questions or require additional information. Thanks, Nick Haws, PE, LEED AP NORTHERN ENGINEERING 11 /4/2011 Earth Engineering Consultants, LLC EEC Project No. 1124098P August 2, 2013 Page 2 project along with the current LCUASS Pavement Design Criteria. Recommended pavement sections based on those evaluations are provided on the attached summary tables included with this report. PAVEMENT SUBGRADE PREPARATION The subgrade soils are generally low to moderate strength sandy lean clays to gravelly lean clays exhibiting generally low swell potential characteristics and cleaner sands and/or gravels with increased depths that essentially exhibited no swell. As outlined in our subgrade report dated August 1, 2013 we recommended the exposed subgrades within the interior roadway alignments as well as those along the Drake Road widening section be proof -rolled and recompacted to confirm the stability of the subgrade and the subgrade preparation should be completed in general accordance with the recommendations presented in the LCUASS Pavement Design Manual — Chapter 22. The proof -rolls should be observed and approved by the geotechnical engineer prior to placing the approved aggregate base course (ABC) material. Soft or weak areas delineated by the proofrolling operations should be undercut or stabilized in -place to achieve the appropriate subgrade support. If the subgrade becomes unstable or exhibits pumping, due to wet weather, we recommend the implementation of a subgrade stabilization process, such as a fly ash treatment. Cohesive subsoils, when moisture mitigated, (i.e., overexcavated and moisture conditioned to near optimum moisture content and recompacted to at least 95% of the material's standard Proctor density to reduce swell potential characteristics), have a tendency to pump and become unstable. Fly ash treatment, if required at time of proof roll, would consist of blending 12% by dry weight of Class C fly ash in the top 12 inches of the subgrades. The blended materials should be adjusted in moisture content to slightly dry of standard Proctor optimum moisture content and compacted to at least 95 % of the materials maximum dry density as determined in accordance to the standard Proctor procedure. Based on our ~ understanding, and as recommended in our geotechnical exploration study dated July 31, 2013, which provided the field and laboratory test results for this portion of the interior roadways within the Bucking Development, Class "C" fly ash should be incorporated into the upper 12-inches of the prepared subgrade section as a stabilization and swell mitigation approach. Compaction of the subgrade should be completed within two hours after initial blending of the Class C fly ash. A swell mitigation approach would not be necessary for the Drake Road widening improvements. In lieu of moisture conditioning the on -site cohesive subsoils to mitigate for swell, consideration could also be given to replacing the cohesive materials with an approved, non -expansive granular fill material such as a CDOT Class 7 ABC or equivalent. Placement and compaction of an approved granular fill material should conform to those recommendations as previously provided. Earth Engineering Consultants, LLC EEC Project No. 1124098P August 2, 2013 Page 3 Care will be needed after preparation of the subgrades to avoid disturbing the subgrade materials. Positive drainage should be developed away from the structures to avoid wetting of subgrade materials. Subgrade materials becoming wet subsequent to construction of the site improvements can result in unacceptable performance. The recommended pavement sections provided herein are minimums and periodic maintenance should be expected. Since the cohesive soils on the site have some shrink/swell potential, pavements could crack in the future primarily because of the volume change of the soils when subjected to an increase in moisture content to the subgrade. The cracking, while not desirable, does not necessarily constitute structural failure of the pavement. Stabilization of the subgrades as provided herein will reduce the potential for cracking of the pavements. Long-term pavement performance will be dependent upon several factors, including maintaining subgrade moisture levels and providing for preventive maintenance. The following recommendations should be considered the minimum: • The subgrade and the pavement surface should be adequately sloped to promote proper surface drainage. • Install pavement drainage surrounding areas anticipated for frequent wetting (e.g. landscaped and irrigated islands, etc.), Install joint sealant and seal cracks immediately, • Seal all landscaped areas in, or adjacent to pavements to minimize or prevent moisture migration'to subgrade soils; • Placing compacted, low permeability backfill against the exterior side of curb and gutter; and, • Placing curb, gutter, and/or sidewalk directly on approved proof rolled subgrade soils without the use of base course materials. Preventive maintenance should be planned and provided for through an on -going pavement management program. Preventive maintenance activities are intended to slow the rate of pavement deterioration, and to preserve the pavement investment. Preventive maintenance consists of both localized maintenance (e.g. crack and joint sealing and patching) and global maintenance (e.g. surface sealing). Preventive maintenance is usually the first priority when implementing a planned pavement maintenance program and provides the highest return on investment for pavements. Prior to implementing any maintenance, additional engineering observation is recommended to determine the type and extent of preventive maintenance. Earth Engineering Consultants, LLC EEC Project No. U 24098P August 2, 2013 Page 4 Site grading is generally accomplished early in the construction phase. However as construction proceeds, the subgrade may be disturbed due to utility excavations, construction traffic, desiccation, or rainfall. As a result, the pavement subgrade may not be suitable for pavement construction and corrective action will be required. The subgrade should be carefully evaluated at the time of pavement construction for signs of disturbance, rutting, or excessive drying. If disturbance has occurred, pavement subgrade areas should be reworked, moisture conditioned, and properly compacted to the recommendations in this report immediately prior to paving. Please note that if during or after placement of the stabilization or initial lift of pavement, the area is observed to be yielding under vehicle traffic or construction equipment, it is recommended that EEC be contacted for additional alternative methods of stabilization, or a change in the pavement section. We appreciate the opportunity to be of service to you on this project. If you have any questions concerning this report, or if we can be of further service to you in any other way, please do not hesitate to contact us. Very truly yours, Earth Enfineering Consultant, LLC David A. Richer, P.E. Senior Geotechnical Engineer Reviewed by: Lester L. Litton, P.E. Principal Engineer cc: Bellisimo, Inc. — Mr. Nico Campana: ncampana wbellisimoinc.coin Bellisimo, Inc. — Ms. Elissa Palmer: epalmer(dlbellisimoinc.coni, and Mr. Tony Campana: tonv(ktheI00octane.com Gerrard Excavating, Inc. - Mr. Bill Nicholl: bnicholl(d, eerrardinc.com City of Fort Collins — Mr. Rick Richter: rrichter(i:fcgov.com Mr. Wayne Lenard: wlenard(u;fca v.com C m A .o 0 fti 1 o -♦ ou•,+ I ' O i I-. tt.zl I 1 ` LM ML L•LL Y S, 3 •t•s�TI , _ I \ U So wg 1 i� el 8 s l iKW f fit 1i '� tA s i t2.01 _ ten, - ` - - -- OVC)b 3NI-IU39W(1 -7 A r! 2 9 13 \ ti -14 r t, Legend $ Approximate Boring Locations ' A Site Photos /Photos taken in approximate location, in direction ofarrow/ Figure 1: Boring Location Diagram Bucking Horse Pavements - Filing 1, Phase III Fort Collins, Colorado North EEC Project #: 1 124098P Date: July 2013 Not to scale Earth Engineering Consultants, LLC Z U) Cd C lQ O m (O O {�pp O c'M Mcc ` m O (M U Cf H m O O Cl) r ~ c;C O CN N N co � ,Cd N A O O O F O c n 8 N O y �- o ri o d W 0 = y O 0 MO O C m U C1 ..r C =) LO N 0 M N N i C oN0 O N y C V C y p O O 7 'O m Y 4 (6 C,4 L) N to IE U)wU) Z d n _Im ` p > �0 � :3 - O O M `m �C c a E ci 0 V M LO ~ GOO N 7 E W C N M ui Z c t O Q O rO CCC Q V a LU Z U) Z C v N �- N OI1 O ' N M U c E $ Mo n U N T O O M N f'li «. p Cr1 N LV Y 0 ui L cl - W 0 Q d N O a £� o 0 0 0- > LU >N a Z x N a y. vi V 2 N C Z N F m — CD a M .a E z ° ae N m g « 2 2 W N Q N y DI ° N m e g z a to � 2 o ' �i��� J N C °O LL N U y N N , to 'Np d d m >' G N G1 K w '0 ` 41 C1 t m fi E 3 m m a E N U N c 7 0 Q = m IL E p T c O m (7 H E N LL N A i Z 2 a > > a m u = p .. ° c 2 a y U) ° ° a p v •p '�° w tll W w 16 lG c p1 C) y d aEi > v > Y v a m c w °c m in a C m } C O 2 m `- m U m m N m N g a v , C y 0 o � C 0 C N M d � l9 � L d a 0_ zCL o ° w O p J ' v ° m 0 0 o v C.1 c 0 t G°) m 0: T r� o V M N M w> U 04 E > 0 a a) N w� w o 0 w� d N vOi E N U a � N N 0 o Z; N Y U Co 0 N C 0 c w Cc M 3 o c N }0CM Cc Y -o v N (0 N� m 0 L c ° O f0 rn a M 5 J a c� 2 o U 0 •: c o n a c N c c 0 0 m o > a E jY L U CDw W -a0 y0 Y O a cc c 'c 0)i v E .3 c a� L 0 d O d (A c O � E f0 as � N m 0 c Andrew S. Gingerich From: Nick Haws <nick@northernengineering.com> Sent: Friday, August 31, 2012 8:37 AM To: Andrew S. Gingerich Subject: RE: Bucking Horse - rain garden detail Regarding the distance between the curb opening and the flare... I am going to revise the opening to a 1.0' bottom width and a 2.0' top width. This will provide 2.0' of full height curb before the flare, and then a 3.5' transition 7om6" to 0" across the -flare � tself. This is with the 20.0' curb cut as currently drawn (projected to back -of -concrete to back -of -concrete). Nick Haws, PE, LEED AP NORTHERN ENGINEERING From: Nick Haws Sent: Thursday, August 30, 2012 9:58 AM To: 'Andrew S. Gingerich' Subject: RE: Bucking Horse - rain garden detail Andrew, Have you gotten any feedback from Sheri on this? Nick Haws, PE, LEED AP NORTHERN ENGINEERING From: Nick Haws Sent: Friday, August 24, 2012 4:59 PM To: 'Andrew S. Gingerich' Subject: Bucking Horse - rain garden detail Andrew, Attached is the PDF you requested. If you, Sheri, or anyone else would like to see something different, we certainly can do so prior to printing mylars. Nick Haws, PE, LEED AP NORTHERN ENGINEERING 200 South College Avenue, Suite 10 1 Fort Collins, Colorado 80524 0: 970.221.4158 ext. 5414 1 D: 970.568.5414 I M: 970.690.0927 F: 970.221.4159 � niekicr)northerneneineeringcom I www.northernengineering coin Page 1 of 2 Sheri Langenberger From: Sheri Langenberger Sent: Friday, November 04, 2011 8:23 AM To: 'Nick Haws'; Ward Stanford; Aaron Iverson Cc: Marc Virata Subject: RE: Proposed curb cut on Timberline Road Nick Here are our thoughts on this item after discussing this at Transportation Coordination yesterday. An access at the north end of Outlot C of Sidehill 2"d Filing maybe possible, but before any decision on this could be made we need to see/understand what the proposal for the site is and if the access can work. If an access is agreed to the ODP would need to be amended to show the additional access off of Timberline. Concerns and Items that will need addressed regarding the review of an access point at this location are: o Volume and type of vehicles using this. If a decel lane is needed this will be hard to implement. A lot of work went into preserving the trees that are along the frontage of the property. o Location — we don't see it being able to be located as far north as you have indicated, due to the existing inlets, turning radii requirements, and the need for the driveway to intersect at close to 90 degrees. o Sight Distance — does the hill pose a sight distance problem? Will an access even r-in r-out meet sight distance requirements? o This stretch of roadway is currently on the list for completion of the west side of the road and the median. It is tentatively scheduled for 2014. o To control an access at that location would require the Timberline median to be extended south of the access. From: Nick Haws [mailto:nick@northernengineering.com] Sent: Friday, November 04, 2011 7:38 AM To: Sheri Langenberger; Ward Stanford; Aaron Iverson Subject: RE: Proposed curb cut on Timberline Road What was the general consensus on this? Thanks, Nick Haws, PE, LEED AP NORTHERN ENGINEERING From: Nick Haws Sent: Tuesday, November 01, 2011 12:19 PM To: Ward Stanford Cc: Marc Virata Subject: Proposed curb cut on Timberline Road Ward and Marc, I was wondering how receptive the City would be to another access point to Timberline Road with the Sidehill development. The location being considered is located in Outlot C of Sidehill Filing Two (Jessup Farm parcel). The attached PDF shows the approximate spacing and relationship to other access points along Timberline Road. 11/4/2011