ART Standards May 15 2012.pdf

City of Durango Multi-Use Trail Standards May 15, 2012

Trail Design and Layout:

1. General Design: The multi-use trail shall be minimum 10’ wide, 6” thick concrete paving with a two foot, soft-surface shoulder on each side of the trail. General design of the trail shall meet guidelines provided by Guide for the Development of Bicycle Facilities by American Association of State Highway and Transportation Officials and shall meet requirements of 2010 ADA Standards for Accessible Design. Trail and structures shall provide for an AASHTO H10 design vehicle.

2. Alignment: The trail alignment shall meet guidelines provided by Guide for the Development of

Bicycle Facilities by American Association of State Highway and Transportation Officials. A design speed of 20 miles per hour shall be utilized in design of the trail unless otherwise specified by the City. The design speed for grades over 4% shall be increased to 25 miles per hour. The alignment shall preserve stands of existing vegetation whenever possible and minimize the amount of cut, fill, and retaining walls when practical. Alignment shall provide for AASHTO H10 design vehicle.

3. Grade: Grade and running slopes shall meet guidelines provided by Guide for the Development of

Bicycle Facilities by American Association of State Highway and Transportation Officials and shall meet requirements of 2010 ADA Standards for Accessible Design. Running slopes shall be kept to a minimum; grades greater than 5 percent are undesirable.

4. Intersections and Signage: All trail intersections and trail signage shall be designed to meet guidelines provided by Guide for the Development of Bicycle Facilities by American Association of State Highway and Transportation Officials and MUTCD.

5. Drainage: Site grading shall provide for drainage away from the trail surface. The concrete trail shall have a 2% cross slope to promote drainage. The 2’ wide soft surface shoulder shall have a 2% cross slope to promote drainage away from the concrete surface. Culverts shall be installed to provide drainage under the trail as opposed to sheet flow drainage across the trail surface.

Drainage swales shall be installed with a maximum 3:1 side slope off of the soft-surface trail edge.

Sumps at drainage inlets and outlets shall be a minimum of 5 feet off edge of soft-surface trail and shall provide an adequate buffer between the trail and sump. Location and design of drain inlets shall be reviewed by City staff

Construction Standards:

FIBER REINFORCEMENT:

1. Acceptable fiber-reinforced concrete material for concrete trails shall conform to ASTM C94, ASTM C1116, ASTM C1018, ASTM E119, and the following characteristics:

A. Chemical – shall be virgin polypropylene which is inert to alkali and chemical attack;

fiberglass or polyester based fibers are unacceptable.

B. Physical – shall be fibrillated, twisted-bundle form; monofilament or untwisted fibers are unacceptable.

C. Length – minimum fibrous length shall be based on the top-size coarse aggregate –

Multi Design Gradation.

2. Fiber-reinforced concrete shall be added directly to the concrete at the time of batching in amounts in accord with approved submittals for each type of concrete required. Mix concrete in strict accord with fiber-reinforced concrete manufacturer, instructions, and recommendations. Quantity shall be used at a minimum rate of 1.5 pounds per cubic yard of concrete. Pre-project trials shall be utilized to determine acceptable finishability by the Engineer and Parks and Recreation. The manufacturer shall provide the services of a qualified technician to instruct the concrete supplier in proper batching and mixing of materials to be provided.

CONCRETE TRAIL EDGE:

1. Concrete trail forms to include ½” forty-five degree cant at upper edge of concrete surface to provide ½” forty-five degree lip/chamfer at edge of concrete trail.

PLACEMENT ADJACENT TO EXISTING CONCRETE:

1. Install smooth, steel dowels eighteen inches on center at all concrete to be installed adjacent to previous concrete flatwork. Smooth dowels to be 24” in length and ½” diameter. One end of dowel shall be coated with a nonbinding agent. Dowels to be installed, inspected, and approved by City Inspector prior to installation of concrete.

EXPANSION JOINTS:

1. Expansion joint material shall be of ¼ to ½ inch thick non-extruding preformed joint filler material cut to the configuration of the full depth and width of the concrete section. Expansion joint material shall conform to AASHTO M33. Joint filler shall be left ¼" below the surface and joints are to be sealed.

2. Expansion joint material (filler) shall be placed prior to placing of concrete and shall be provided at the following locations:

A. every 80 linear feet of concrete trail B. at all tie-ins to adjacent to walks, drives, and concrete paving C. between the concrete trail and any fixed structure such as a building or bridge D. around fire hydrants, poles or manholes E. as directed by the Engineer

3. Joint filler shall be secured and held in place during placing and consolidation of concrete.

4. All expansion joints to be sealed with Sikaflex 1CSL joint sealer or approved equivalent per manufacturer’s instructions. All joints shall be cleaned of debris and dust prior to installation of sealer.

CONTRACTION JOINTS:

1. All concrete trails shall be divided by transverse contraction joints at right angles to the curb line and at intervals not to exceed ten (10) feet. Joints shall be one-eighth (1/8) inch wide and shall extend to one-fourth of the concrete depth.

2. Contraction joints shall be saw-cut. Sawing shall be done within twenty-four (24) hours after the concrete has set to prevent the formation of uncontrolled cracks.

3. All contraction joints to be sealed with Sikaflex 1CSL joint sealer or approved equivalent per manufacturer’s instructions. All joints shall be cleaned of dust and debris prior to installation of sealer. Install to provide a clean and smooth seal.

FINISHING:

1. After the concrete has been leveled and the initial set has taken place, all exposed surfaces shall be carefully finished with wood or magnesium floats and steel trowels to a smooth but not slippery finish. Exposed faces of concrete trail shall be finished to true line and grade as shown on the approved plans. The final texture shall be a light broom finish of 1/16” to 1/32”.

2. A ½”, 45 degree chamfered edge shall be formed into all trail edges. Special care shall be taken to insure a straight, neat appearance along edges or sidewalks, slabs and joints.

3. Forms shall not be disturbed until the concrete has hardened sufficiently to hold its shape but forms shall be removed promptly thereafter to allow completion of curing operations. After removal of forms, all bulges, fins, form marks or other irregularities that may adversely affect the appearance or function of the concrete shall be removed. Also, honeycombed places and other minor defects shall be filled with mortar composed of one part Portland cement and two parts of fine aggregate, which shall be applied with a float. This plastering treatment is not allowed on the exposed face of trail.

RAILING STANDARDS:

1. Railing to be fabricated and installed per attached detail. Railing to be installed at all locations where trail abuts a vertical drop of 30” or greater and any location where there is fall-off slope of 3:1 or greater within 5’ of the trail edge. Railing to be located adjacent to steep slopes or at other locations as required by the City of Durango.

2. All tube material for railing shall conform to A.S.T.M. A-500, Grade B. Painting of Railing shall conform to CDOT Specification Section 509.

3. Paint to be Shermin Williams DTM-Alkyd color 6258, Tricorn Black, semi-gloss.

4. Expansion joints in railing shall be spaced no greater than 60 feet apart.

5. All railing material is required to be certified by the contractor as “American Source” material.

6. Field verify all measurements prior to construction of railing. All rail posts and pickets shall be set in a plumb position.

LIGHT STANDARDS:

1. Lights along the Animas River Trail shall be HADCO light fixture C3325. Light fixture to provide full-cutoff shield and house side shield. 70W lamp to be installed. Lamp post and base to be 12SEAF-5.0/14S-20”W-TT/3x3-20”Wash with “Animas River Trail” cast into top, black 12 feet tall pole with decorative base as provided by Mountain States Lighting, 1-303-838-4430. Lighting shall meet City of Durango standards and specifications.

2. Any lighting other than the standard Animas River Trail lighting shall be approved by the City of

Durango.

3. Provide two feet minimum of clearance between concrete trail edge and edge of light foundation.

4. Light spacing and location shall be field reviewed and approved by City of Durango Parks and Recreation.

5. All electrical conduits to be trenched and installed per City of Durango standards.