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9.C.1. PRSR 01-10-2001 ek? c Item # 9.C.1. • City of MEMORANDUM Elk ,. River TO: Park and Recreatio Commission FROM: Michele McPherso"r'irector of Planning DATE: January 10, 2001 SUBJECT: Review and Approve Trail Construction Standards Request The Commission is asked to review and approve a proposed trail construction standard for the construction of bituminous off-street trails. Attachments • • Bituminous Trail Typical Section • Pedestrian Curb Ramps for Trails • Aggregate Mixture • Thickness and Surface Smoothness Requirements • Longitudinal Deviation Analysis Staff has prepared the attached trail cross section and pedestrian curb ramp details for inclusion in the City's construction standards manual. These standards would be presented to developers for inclusion in their construction documents for the construction of off-street bituminous trails. These drawings and information reflect discussions conducted with staff and Commission Dave Anderson. We believe that these are manageable and cost-effective standards for trail construction. In order to maintain these standards and to insure proper installation, trail construction will be discussed as part of all pre-construction meetings and with all developers. Contractors will also be required to arrange inspection of the sub grade, aggregate base, and wear-course installation as well as restoration with superintendent Phil Hals. The typical trail section drawing will be revised to eliminate the point in the transition area between the trail and the side slopes. 13065 Orono Parkway • P.O. Box 490 • Elk River, MN 55330 • TDD & Phone (763) 441-7420 • Fax(763) 441-7425 Memo to Park&Recreation January 10,2001 Page 2 • Recommendation Staff recommends that the Commission review the attached construction standards, provide changes or amendments, and, if appropriate, approve the trail standard. • • S:\PLANNING\M I C H MC\PARKN RE C\tra i lstd.d oc RESTORE DISTURBED AREA WITH 2" TOPSOIL (MINIMUM), SEEDING, FERTILIZING, AND PLACEMENT OF EROSION CONTROL BLANKET. SEED MIX TO BE TYPE 50A 10' WITH APPLICATION RATE OF 50 LBS/ACRE PLUS 10 LBS/ACRE OF RYE SEED. 1 — 2" BITUMINOUS (2350 WEARING COURSE MIXTURE) 4" CLASS 5 AGGREGATE BASE APPROVED, COMPACTED SUBGRADE TRAIL TYPICAL CROSS SECTION PROPOSED GRADE 10' h- 2' 0.6% TO 5.0% ALLOWABLE 2.00% LONGITUDINAL GRADE IF WHEELCHAIR 2. ACCESSIBLE. 8% ABSOULUTE MAXIMUM • M 7 ALLOWABLE LOGITUDINAL GRADE. 7 44. TRAIL 4 RFC TRAIL TYPICAL SECTION ERSTD–trail wr '1 1 STANDARD PLATE BITUMINOUS TRAIL NO. TYPICAL SECTION City of Haivad R C ,Ccrn Elk 'ever 2010 CONSI.TNG ENGINEERS 6' S 10' WIDE TRAIL 10.00' RP�\vs EXPOSED AGGREGATE o\ :° CONCRETE RAMP 0 10 PLAN VIEW I I 19' 6' ►x 7' ►x 6' ROUND ALL 410 SLOPED INTERSECTIONS 1 DEPRESSED CURB DETAIL CURB HEIGHT CUT OUT . BACK OF CURB = p.6� MIN. SLOPE o 1/4" RISE MAX. SLOPE = .u' 1/2" EXPANSION JOINT CURB AND GUTTER SECTION 10 SURFACE TREATMENT — AFTER NORMAL CONCRETE FINISHING, THE CONCRETE SHALL BE LIGHTLY RINSED TO EXPOSE AGGREGATE. THE EXPOSED AGGREGATE SHALL PROTRUDE AT LEAST 3/16" ABOVE THE ERSTD—trail CONCRETE SURFACE. r '� r � STANDARD PLATE . `� PEDESTRIAN CURB RAMPS City f ,�a NO. FOR TRAILS Y ►`� Elk 2004 Hamad R.Green Company •ive r CONSULTING ENGINEERS 2350 • Plant Mixed Asphalt Pavement Sections 2331 and 2340 of the Standard Specifications are deleted and replaced with the following; 2350.1 DESCRIPTION This work consists of the construction of one or more pavement courses of hot plant mixed asphalt-aggregate mixture on the approved prepared foundation, base course or existing surface in accordance with the specifications and in conformity with the lines, grades, thicknesses and typical cross sections shown on the plans or established by the Engineer. 2350.2 MATERIALS A-Aggregate Al General Requirements The aggregate blend used in the work shall conform to the requirements of Section 3139, as revised following this provision, for the particular material specified, except as hereinafter otherwise or additionally stipulated. Class B aggregate will not be allowed in the final lift of roadways with traffic levels over 10 million, 20 year design ESAL's. A2 Aggregate Gradation for Asphalt Mixtures • The combined aggregates, including mineral filler when required, shall conform to the following gradation requirements. Table 2350-1 Broad Band Aggregate Gradation for Asphalt Mixtures ( % passing of total washed gradation) Sieve Size mm (in) 1 2 3 37.5 (1 1/2") 100 - - - 25.0 (1") 90-100 100 - - 19.0 (3/4") 55-90 90-100 100 - 12.5 (1/2") - 45-90 90-100 100 9.5 (3/8") - - 35-90 90-100 4.75 (#4) 15-70 20-75 20-80 25-85 2.36 (#8) 10-55 15-60 15-65 20-70 0.075 (#200) 2-7 2-7 2-7 2-7 B Additives An additive is any material added to a asphalt mixture or material, such as mineral filler, hydrated lime, asphalt additives, antistrip, and similar products that do not have a specific pay item. When a Contract requires additives, compensation is included with the pay items for the appropriate mixture. If the Engineer directs the Contractor to incorporate additives, the • Trench rollers shall be self propelled and have a mass of not less than 4400 kg per meter (2960 III lb per ft) of width. C5 Mixture Temperature Controls If compaction is obtained by the ordinary compaction method, the minimum laydown temperature in all courses (as measured behind the paver or spreading machine) of the asphalt mixture shall be in accordance with the temperature requirements of Table 2350 - 11. Table 2350 -11 Mixture Temperature Control Air Temperature Compacted Mat Thickness, mm(A) °C (°F) 25 mm (1 in) 40 mm (1-1/2 in) 50 mm (2 in) 75 mm (3 in) or greater +0-5 (32-40) -- 129 (B) (265) 124 (255) 121 (250) + 6-10 (41-50) 130 (B) (270) 127 (260) 121 (250) 118 (245) + 11-15 (51-60) 127 (B) (260) 124 (255) 118 (245) 115 (240) + 16-21 (61-70) 121(B)(250) 118 (245) 115 (240) 113 (235) + 22-27 (71-80) 118 (245) 115 (240) 113 (235) 113 (235) + 28-32 (81-90) 113 (235) 110 (230) 110 (230) 110 (230) + 33 (91+) 110 (230) 110 (230) 110 (230) 107 (225) - (A) Based on approved or specified compacted lift thickness. (B) A minimum of one pneumatic-tire roller shall be used for intermediate rolling unless otherwise directed by the Engineer. The Engineer may specify or modify in writing (with concurrence from the Bituminous Engineer) • a minimum laydown temperature. 2350.7 Thickness and Surface Smoothness Requirements A Thickness After compaction the thickness of each course shall be within a tolerance of 6 mm (1/4 in) of the thickness shown in the Plans, except that, if automatic grade controls are used, this thickness requirement will not apply to the first course placed. This thickness requirement will not apply to a leveling course whether or not automatic grade controls are required. Any part of any course that is constructed to less than the minimum required thickness may be removed and replaced at the discretion of the Engineer. On that portion of any course constructed to more than the maximum permissible thickness, the materials used in the excess mixture above that required to construct that portion of the course to the Plan thickness plus 6 mm (1/4 in) will be excluded from the pay quantities and may require removal and replacement at the discretion of the Engineer. Cores taken for density determination shall be measured for thickness also. Each core shall be measured 3 times for thickness prior to sawing. Report the average of these three measurements. Each lot's average core thickness shall be documented and submitted to the Engineer. If the average of the two Contractor cores exceed the specified tolerance, an additional two cores may be taken in the lot in question. The average of all core thickness • measurements per course will be used to determine compliance with thickness specifications. A profilogram will be made for each segment of 15.24 m (50 ft) or more. The profilogram will 0 include the 4.57 m (15 ft) at the ends of the section only when the Contractor is responsible for the adjoining surface. End of run areas not included in the profilograph trace and any sections of pavement less than 15.24 m (50 ft) in length shall be checked longitudinally with a 3.028 m (10 ft) straight edge and the surface shall not deviate from a straight line by more than 3 mm in 3.028 m (1/8 inch in 10 ft). The profile trace and index for each segment of pavement must be furnished to the Engineer within 48 hours after each days run. Identification of all bumps and dips, with signature of the Operator shall be included with the submitted trace. For each day's run, an evaluation will be submitted to the Engineer within five days after pavement placement. The evaluation submitted shall include identification of segments which may qualify for less than 100 percent payment, segments that qualify for incentive payment and segments to be corrected. The Contractor will be responsible for all traffic control associated with the smoothness testing. Any portion of the project may be tested if the Engineer determines that the Contractor's test results are in question. If results are found to be inaccurate, the Contractor will be charged at a rate of $155.34 per lane km ($250 per lane mile) that is retested, with a minimum charge of $500.00. If the results are found to be accurate, the Department will be pay the Contractor at a rate of$155.34 per lane km ($250 per lane mile) that is retested, with a minimum charge of • $500.00. C4 Profile Index The profilograph trace will be evaluated by the Contractor for the profile index (PI) in accordance with California Method 526 on file with the Bituminous Engineer. The original trace shall be provided to the Engineer for verification of the Contractor's evaluation. A profile index shall be calculated for each segment. The index will be determined by summing the vertical deviations outside a 5 mm (0.2 in) blanking band. The units of this index are mm per km (inch per mile). When there is a segment of 76.2 m (250 ft) or less in length, the profilograph measurements for that segment shall be added to and included in the evaluation of the adjacent section to that segment. Bumps and dips exceeding 10.2 mm in a 7.62 m (0.4 inch in a 25 ft) span shall be identified separately. C5 Surface Correction All areas represented by deviations of 28 mm (1.1 in) or more, as measured by the 7.62 m (25 ft) profilograph, will be corrected by the Contractor. The Contractor may elect to correct dips or bumps of 10.2 to 25 mm (0.4 to 1.0 in) in a 7.62 m (25 ft) span. The Contractor will be assessed a penalty for dips or bumps of 10.2 to 25 mm (0.4 • to 1.0 in) that are not corrected. Bumps and dips not corrected will also be included in the