Life-Cycle and Playability Analysis of Natural Turfgrass and Synthetic Infill Playing Surfaces Under Field Conditions

Graduation date: 2017The perception of a long-term cost advantage of synthetic infill turf systems relative to natural grass systems has contributed to a rise in their popularity in the USA. However, few comprehensive cost assessments of natural grass and synthetic infill systems exist. There are also no studies looking at interactions between surface quality, maintenance practices, and real foot traffic on athletic surfaces. Currently, simulated traffic is the most commonly used method for assessing wear tolerance on athletic playing surfaces. This series of case studies took five natural grass and five synthetic infill fields in the Willamette Valley, OR, and gathered information on their maintenance practices, costs of installation and maintenance, surface quality data, and player use hours from field managers, athletic directors, coaches, online schedules, and player rosters. This information was used to perform a life cycle analysis and find the maintenance cost of providing an hour of player use for both field types. A simple linear regression analysis was also performed exploring the relationships of maintenance practices and real player traffic with percent green cover and surface hardness on natural grass surfaces, and infill depth and surface hardness on synthetic infill surfaces. \ud Findings from this work determined that the average cost of installing a synthetic field was $162.66 m² and the average annual equivalent was $20.10 m². The average cost of installing a natural grass field was $45.61 m² and the average annual equivalent was $10.11 m². It was found that the average cost of providing an hour of use to a single person was $3.48 for the natural grass fields averaged and $3.25 for the synthetic fields.\ud This series of case studies suggests that mean percent green cover showed little variation across the month of July and no variation in the month of November on natural grass fields. The only statistical difference was likely associated with the lack of summer irrigation on one of the fields in the month of July. This was likely due to good growing conditions under irrigation in the summer and excess soil moisture in the rainy season. Reducing mean surface softness on natural grass fields was attributed to increased cultivation events leading to firmer fields while higher mowing heights were associated with increased surface softness in July and November.\ud With synthetic infill fields there was a correlation between surface softness and infill depth. The maintenance practices of brooming and grooming, followed by debris removal, and crumb rubber replacement were associated with improving surface softness and increasing infill depth