Track & Field Facilities

• Design
• Construction
• Renovation
• Maintenance
• Rules & Regulations

Track & Field Facilities Designs

Survey and Layout
The largest and most expensive sports field discussed in this book is a field with a surrounding 400-meter track. With a length of nearly 600 feet (between the outside edges of the track arcs) and a width of almost 270 feet (between the outside edges of the track straightaways), the total size of the playing surface is 162,000 square feet. (The next biggest field is a major league baseball field, which has approximately 120,000 square feet inside the fences.) Adding enough space around the track to provide for cuts and fills, catch basins and swales (typically at least 40 feet in each direction) increases the space requirement to 238,000 square feet or approximately 5.5. Acres. Of course, the 40 foot minimum space around the outside of the track is not even enough room for grandstands. With spectator seating, the total space requirement could easily approach 7 acres.
 
The design process begins with laying out the outer boundaries of the track to determine whether there is sufficient space to build the facility. After verifying the space requirements, determine the exact location of the track by setting the center line and the two radius points 328.08 feet (100 meters) apart. A standard 400-meter track is divided into 4 segments--two straightaways and two radiuses--with each segment being 100 meters. (For more information on track dimensions, see Figure 16.6 in this chapter.)
 
The next step is to perform a topographic survey. Survey enough land outside the track to get a clear understanding of the contour of the surrounding terrain. That will help determine the need for cuts and fills, catch basins, and swales, and will also help in determining a finish grade of the track. (Like any other sports field, a track and field facility must be isolated from its surroundings, and expected to drain away only the water that falls on the facility itself.)
 
The most common way to perform a topographic survey is to lay out a 50-foot grid pattern and use those points to take elevation readings. When using a grid pattern, the planner uses those elevations to develop a contour plan that includes both existing and proposed contour lines. Spot elevations must also be included in the proposed grading plan, because a 50-foot grid will miss the most important elevations, such as the middle of the field and the edges of the track.
 
Another way to perform a topographic survey is to lay out the entire track and field and take predetermined spot elevations of the long axis of the field, the inside and outside edges of the track, and the area 40 to 50 feet outside the track. These readings will provide an immediate understanding of the existing topography as it relates to the facility to be constructed.
 
16.2b Design Criteria for New Construction
 
The highest point of the field is the center line between the two radius points of the track. The field is crowned and sloped away from the center line in all directions at a consistent 1% to 1½% grade.
 
The maximum percentage of slope for tracks and runways in the lateral (side-to-side) direction for high school is 2%, for college it is 1%. It's wise to use a percentage of slope of 1%, even for high school tracks and runways, since that is sufficient for surface runoff. Both high school and college rules allow a maximum of .1% slope in the running directions except the high jump event. For high jump, the percentage of slope in the approach run is 1% for high school competition, .4% for college.
 
Plan to have a smooth transition between the track and field so athletes running off the field of play will not be disturbed by an uneven surface or by hazards like protruding or sunken catch basins.
 
Since the construction of a field is much different than the construction of a track, make sure all contractors understand that there are important differences in the methods to be employed. A track is constructed much like a road and needs to be compacted to 98%, but a field needs to be constantly scarified (the soil needs to be loosened) to prevent excessive compaction.
 
A common mistake, and one that is found in many specifications for building sports fields, is to include instructions to compact the field to 98%. This much compaction will stop internal drainage and inhibit root growth. The result will be thin turf and muddy conditions in rainy weather. The solution to this problem is very simple; just add the instructions, "Avoid overcompaction of the sub-base" and "scarify sub-base before installing topsoil" to the specifications to alert the excavator to the drainage dynamics at work in the field system.
 
16.2c Facility Designs with Preferred Contours
 
As we have observed above, a track and the field it surrounds have something in common with a baseball diamond, because each is made up of separate structures that must work together as one functional unit. The main difference between the two facilities is that a baseball field has many possible combinations of contours that can work well together, while a track and the enclosed field can practically be designed in just one way, making the job easier for the designer.
 
From a practical standpoint, the only way to grade a track is with the entire inside edge level and 1% lower than the outside edge, so that water runs off toward the infield. Since the inside of the track is level, the field enclosed by the track has to be crowned. (The only other possibility would be to slope the entire field inward toward catch basins at the center, and this would make the field useless for most sports.)
 
If a track is being constructed around an existing field that slopes from end to end, it may be desirable to have one end of the track lower than the other. The rule book allows a maximum of .1% slope in the running direction, so one end of the track can be as much as eight inches lower than the other. Since this grade change is allowed by the rule book, the "sloped" track may fit into an existing site much better than a "level" track would.
 
In designing the field contours, a consistent percentage of slope is the best way to avoid wet spots. If the percentage of slope is inconsistent, the designer will be faced with one of two problems: either there will be large wet areas where the slope is less than a 1% slope, or there will be unsightly hills and valleys (with a percentage of slope much higher than 1%) to prevent swampy conditions. In most cases, these problem areas occur at the circular ends of the field and at the straightaways next to the track.
 
The only way to achieve a consistent percentage of slope and avoid these problems is shown in figure 16.1. In this illustration, both the track and the enclosed field have a consistent 1% slope. No other contour plan will provide this consistency.
 
16.2d Track Surfacing Materials
 
The selection of materials for the track begins with the choice of the sub-base material, or aggregates. In order to maintain a firm base of support for the track itself, and make the surface stand up to competitive stress and weather conditions, the sub-base must be the type of aggregates that are commonly used for construction of roads or walks in a particular area. For all-weather tracks (the most common type for new construction today), the type of sub-base aggregate depends on whether asphalt or concrete will be used as the paving material beneath the all-weather surface. In the South, concrete is most often used, because asphalt melts in the heat of the summer. In the North, asphalt is usually the material of choice.
 
Figure 16.1
 
Contour plan for a field with a surrounding 400-meter track--elevations noted in feet.
 
All-Weather Tracks
An all-weather track is one that is topped with a coating of rubber chips that are bonded together with a cementing agent. These rubber coatings are installed to a depth of 3/8" to ½" over an asphalt or concrete base to provide a soft running surface.
 
The preferred method of installing a rubber track is to spread the bonding agent over the track surface, and then spread the rubber chips. This method places a thick layer of rubber between the runner's foot and the paving material below the track, and results in a strong but resilient surface. A less expensive rubber coating is one that is sprayed on with multiple coats of tar. This system does not provide the same depth and softness as poured surfaces.
 
The most popular choices of rubberized coatings are latex or polyurethane, and generally latex is the less expensive of the two. On the other hand, the most expensive rubber coating is one that is orange in color. The reason for the added expense is transportation cost and not superior performance qualities; most orange rubber comes from Europe.
 
Another type of track surface, which is not actually considered a coating or even an all-weather surface, is rubberized asphalt. The rubber is mixed into the asphalt at the plant and installed in a one-step paving process. Some experimental roads are being paved with rubberized asphalt, but for running tracks it is considered the hardest surface in use. Since the rubber is mixed into the asphalt, only a small portion is near the surface to cushion the impact of the runners' feet.
 
Cinder Tracks
All-weather tracks got their name in order to distinguish them from traditional cinder tracks, because the cinder facilities are usually degraded by adverse weather conditions. Despite the fact that cinder tracks can be very soft and comfortable to use, few new cinder tracks are being built today because of the additional maintenance and weather headaches that go with them. It's probably also true that many cinder tracks are being converted to all-weather because boosters and athletic directors see all-weather tracks at neighboring schools, and want to "keep up with the Joneses."
 
Where budgets do not allow the construction of all-weather tracks, many schools have been choosing to install a granular material (instead of cinders) that can be used to support concrete or asphalt at a later date. (If cinders are chosen, they will need to be removed and replaced with a granular material.) The granular materials will support competition until, for instance, local boosters can raise funds to finance the new track.
 
16.2e Enclosed Field Turfgrass Selection
 
Turfgrass selection depends on the type of sports that will be played on the field. For school applications, most tracks surround football/soccer fields, which may also be used for some field events. (See chapters on different sports for the best turfgrass choices for each.) If the field will be used for throwing events such as discus and shot put, a heavy thatch layer is desirable. The thatch layer helps to protect the turf from divoting when a discus or shot put hits the ground.
 
For field events for warm season fields, bermudagrass is the best choice. For cool season fields, a combination of Kentucky bluegrass and perennial ryegrass is a serviceable choice, but a 100% bluegrass field provides the best thatch layer.
 
16.2f Installed Irrigation Systems
 
Figure 16.2 shows an installed irrigation system for a field that is surrounded by a 400-meter track. This system is designed to irrigate the entire area inside the track. (It may be necessary to make adjustments to this plan, depending on the layout of field event structures such as the high jump and the long jump areas.)
 
This design requires water pressure of 75 PSI at field edge and yields a pressure of 60 PSI at the base of the sprinkler heads. Average precipitation rate for this system will be .45 inches/hour for full circle heads and .9 inches/hour for half-circle heads. Running time for 1" watering will be 2 hours 15 minutes for full circle heads, one hour 8 minutes for half-circle heads.
 
16.2g Installed Drain Systems and Catch Basins
 
To complete a successful integration of the track and field, installed drain systems and catch basins are just as important as proper surface grading. Typically, the biggest problem for track drainage is the removal of surface water at the inside edge of the track. Since the outside edge of the track is higher than the inside edge, surface water collects at the lowest point (the inside edge), and may wind up standing on the inner lane itself. Of course, the field contributes to the problem; since the field is higher in the center, surface water flows off the field and toward the inside edge of the track. Installed drain systems and catch basins used in combination are probably the best way to remove surface water from both track and field.
 
Sometimes catch basins are used as the only structures to intercept surface water at the inside edge of the track. In this scheme, as many as 12 catch basins 5 feet from the track and 115 feet apart with 6" deep swales from catch basin to catch basin are necessary. In designing such a system, it's important to avoid installing catch basins with the tops so low that they create an unsafe condition for players or an unsightly appearance of hills and valleys (Figure 16.3). (Fewer catch basins require deeper swales in order to provide adequate surface runoff. This type of drainage plan can lead to some extreme solutions; we've seen catch basins 5 feet away from the track as deep as 24".)
 
The catch basins must have a network of solid pipes (typically 8" to 10" in diameter) that connect them all together, and at least one main outlet pipe is required to service all the catch basins inside the track. The main outlet pipe, which carries the water away from the facility, is usually a large pipe (typically 12" diameter) that connects to an approved (by local code) storm sewer drainage system.
 
Figure 16.2.
 
Track and field irrigation system design.
 
In some parts of the country, it is necessary to install perforated pipe drains beside the track to remove water from the base of the track and prevent surface cracking caused by freezing and thawing. In this case, the catch basins are used as junction boxes for the drain pipes, to collect the water that is removed from the subsurface of the track.
 
Trackside Sand Drains
Another way to solve the problem of standing water at the inside edge of the track is to install a system of sand drains tied together by catch basins. Only four catch basins are required for this kind of system, since their purpose is not to collect surface runoff but to serve as junction boxes. The main advantages of using this system are improved drainage of the inner lane and the elimination of the annoying hills and valleys required by swale-and-catch-basin systems. The field can then be graded at an even percentage of slope all the way to the inside edge of the track.
 
These sand drains begin with the placement of perforated pipe in a cloth-lined trench, followed by pea gravel to within 4" - 6" of the surface. The pea gravel is then topped with coarse sand and seeded or sodded with a washed sod. Once these sand drains are in place, surface water in intercepted (at the low point of the facility) by the coarse sand and allowed to filter down through the sand and pea gravel into the pipe drains below. Figure 16.4 shows a design for a trackside sand drain system.
 
If the perforated pipe is installed so that its highest point is below the subsurface of the track, this installed drain system can serve two purposes: removing subsurface water as well as surface runoff from the track.)
 
If an installed drain system is required for the field, consider a strip drain system that helps to collect some of the surface water as well as subsurface water. The collector pipe for this system can be the same pipe that is used for the trackside sand drain system described above. Under these circumstances, the trackside drain system serves a third purpose, as a collector drain for the field's strip drain system. (Figure 16.5 shows a design for a strip drain system.)
 
Figure 16.4 Trackside Sand Drain System
 
Figure 16.5 Strip drain system.