AsphaltTrails
There are more than 70 miles of trails in the Johnson County Parks and Recreational District.
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ohnson County Parks and Recreational District has created a successful network of recreational asphalt trails and park facilities along eight major streamways in Johnson County, Kansas. The trails system was envisioned as a way to preserve the county's limited land and water resources and to provide an alternative,traffic-free transportation corridor to and from parks, schools and business. The system was also designed to minimize flooding by preserving natural vegetation and natural ponding areas. Since 1987,an average of 100 acres has been added to the park facilities each year. Partnerships with local municipalities have allowed additional acquisition and trail construction along the stream channels. There are now approximately 70 miles of trails within the country park system.
a sheepsfoot roller. Then,approximately 6 to 8 inches of crusher fines and dust are placed on the subgrade as a base course and compacted using three to four passes of a small vibratory steelwheeled roller. Paving of the surface begins at the bridge crossing of major stream channels. Bridges at these crossings have a design-load capacity of 20,000 pounds— enough to carry emergency vehicles but not construction equipment. Consequently,a small,light-duty paving machine is used to place the asphalt mix. The mix is placed in a single 3-to-4 -inch thick lift about 8-feet wide.
base material. County construction personnel do not use a tack coat. At trail intersections,the HMA mix is distributed across the surface by rakes and lutes. The mix is supplied to the paver by 6 to 8 dump trucks. The trucks enter the trails at special access points. Then they back down the meandering trail to the paver. The HMA is compacted using a small vibratory roller. Compaction density is achieved by making three or four passes over the HMA mat. The County does not require density control tests. A local contractor applies a seal coat to the trail surfaces after the first year. Most trail surfaces have been sealed only once in nine years. The oldest trails were sealed again in the summer of 1998.

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