The use of synthetic turf (ST) has become a popular option for many athletic fields. Little is known about how surface hardness and infill depth spatial variability changes over time on third generation (3G) ST athletic fields. A research study was conducted to investigate the impact of field age on surface hardness and infill depth spatial variability from 12 3G ST athletic fields in Tennessee and Georgia (USA) between March 5, 2014 and April 8, 2014. The 3G ST athletic fields tested varied in fiber type including monofilament, slit film, and a combination of monofilament with slit film fibers. All 3G ST athletic fields were directly over gravel with no shockpad present. Surface hardness and infill depth were collected in the same location on all fields. Surface hardness was collected with the Toro Mobile Tester (400–450 samples/field) and infill depth was collected manually with a three-prong infill depth gauge (200–225 samples/field). As field age increased, surface hardness and spatial variability of the surface hardness increased significantly. Surface hardness and infill depth also had a significant negative relationship with one another. The increase in mean surface hardness and variability is partially attributed to infill depth loss and compaction of the remaining infill. Infill depth did not have a significant relationship with age, unless plots were outside the manufacturer’s recommendation for infill depth. Considering the nearly 3000 samples collected in this study, maintaining a minimum infill depth between 30 and 35 mm kept 90% of surface hardness data points below the National Football League limit of 100 Gmax. Results from this study highlight how 3G ST athletic fields can change with age, which may indicate the need for targeted infill applications and decompaction to improve field uniformity over time.

在许多运动场上，合成草皮（ST）的使用已成为一种流行的选择。在第三代（3G）ST运动场上，表面硬度和填充深度空间变异性如何随时间变化知之甚少。在2014年3月5日至2014年4月8日期间，田纳西州和佐治亚州（美国）的12个3G ST运动场进行了田野年龄对表面硬度和填充深度空间变异性的影响的研究。测试了3G ST运动场纤维类型各不相同，包括单丝，切膜以及单丝与切膜纤维的组合。所有3G ST运动场都直接位于砾石之上，没有防震垫。在所有区域的相同位置收集表面硬度和填充深度。用Toro移动测试仪收集表面硬度（400-450个样本/场），并使用三叉式填充深度计（200-225个样本/场）手动收集填充深度。随着场龄的增加，表面硬度和表面硬度的空间变异性显着增加。表面硬度和填充深度之间也具有显着的负相关关系。平均表面硬度和可变性的增加部分归因于填充深度的损失和剩余填充物的压实。除非深度超出制造商建议的填充深度，否则填充深度与年龄没有显着关系。考虑到这项研究收集了将近3000个样本，保持最小填充深度在30到35毫米之间，将90％的表面硬度数据点保持在国家橄榄球联盟规定的100 Gmax以下。这项研究的结果突显了3G ST运动场如何随着年龄而变化，这可能表明需要针对性的填充应用和拆卸，以随着时间的推移提高场的均匀性。