Abstract: A root zone warming system (10) for an athletic field of natural turf (11) supplies positive pressurization to the root zone via a piping network (12) with openings. The system (10) enables control of the temperature of the supplied air by varying the flow resistance at an output end of a constant air supply source (27), such as a positive displacement blower. By increasing the flow resistance at the output end of the blower (27), with a variably controllable valve (29), the operating temperature of the blower (27) increases and thereby causes a corresponding increase in the temperature of the air supplied therefrom. By varying the flow resistance a user can vary the temperature of the air supplied to the piping network (12) and to the root zone, thereby to control the amount of warming of the root zone so as to reduce the onset, degree, or duration of turf dormancy during the winter season.

Abstract: A subsurface warming system for an athletic field supplies positive pressurization to a particulate subsurface via a piping network with pipes that have openings. The system enables control of the temperature of the supplied air by varying the flow resistance at an output end of a constant air supply source, such as a positive displacement blower. By increasing the flow resistance at the output end of the blower, with a variably controllable valve equipped with a modulating actuator, the operating temperature of the blower increases and thereby causes a corresponding increase in the temperature of the air supplied therefrom. By varying the flow resistance, as needed, a user can vary the temperature of the air supplied to the piping network and eventually to the subsurface, to allow the problem associated with freezing of the subsurface during the winter season, for an athletic field that may be an artificial turf.

Abstract: A subsurface warming system for an athletic field supplies positive pressurization to a particulate subsurface via a piping network with pipes that have openings. The system enables control of the temperature of the supplied air by varying the flow resistance at an output end of a constant air supply source, such as a positive displacement blower. By increasing the flow resistance at the output end of the blower, with a variably controllable valve equipped with a modulating actuator, the operating temperature of the blower increases and thereby causes a corresponding increase in the temperature of the air supplied therefrom. By varying the flow resistance, as needed, a user can vary the temperature of the air supplied to the piping network and eventually to the subsurface, to allow the problem associated with freezing of the subsurface during the winter season, for an athletic field that may be an artificial turf.

Abstract: A method of constructing a multi-layered athletic field includes installing surface and subsurface layers over a foundation. The subsurface layer comprises a backing with a plurality of pile filaments secured thereto and extending upwardly to a desired level. A subsurface particulate fill material resides on the subsurface backing, to surround and support the subsurface pile filaments at the desired level, so that the filaments and the particulate are about the same height. This height, and the composition of the subsurface particulate fill material, are selected to achieve a desired degree of shock absorption for the athletic field. The subsurface particles may be retained, as by a hardened liquid binder sprayed thereon. Thereafter, the surface layer is installed on top of the subsurface layer.