# US 8,568,840 B2 · Base for turf system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,568,840 B2 - Document ID: US8568840B2 - Status: Granted - Kind: B2 - Application number: 13/568,611 - Filed: 2012-08-07 - Published: 2012-11-29 - Granted: 2013-10-29 - Earliest claimed: 2007-01-19 - Assignees: Brock USA, LLC - Applicants: Steven Lee Sawyer; Daniel C Sawyer; Richard R Runkles - Inventors: Steven Lee Sawyer; Daniel C Sawyer; Richard R Runkles - Web page: https://patentgrep.com/patent/US8568840B2 ## CPC - E01C 13/02: Foundations, e.g. with drainage or heating arrangements {(E01C13/003, E01C13/083, E01C13/10 take precedence; drainage of soil E02B11/00)} - E01C 3/003: {characterised by material or composition used, e.g. waste or recycled material (E01C3/006, E01C3/04 and E01C3/06 take precedence)} - E01C 3/006: {made of prefabricated single units (E01C3/06 takes precedence)} - E01C 5/003: {characterised by material or composition used for beds or joints; characterised by the way of laying} - E01C 13/08: Surfaces simulating grass {; Grass-grown sports grounds (grass-like surfaces for skiing E01C13/12)} - E01C 13/083: {Construction of grass-grown sports grounds; Drainage, irrigation or heating arrangements therefor} - D10B 2505/202: Artificial grass - Y10T 428/16: Two dimensionally sectional layer - Y10T 428/169: Sections connected flexibly with external fastener - Y10T 428/17: Three or more coplanar interfitted sections with securing means - Y10T 428/192: Sheets or webs coplanar - Y10T 428/23979: Particular backing structure or composition - Y10T 428/24273: including aperture - Y10T 428/24355: Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.] - Y10T 428/24479: including variation in thickness - Y10T 428/249953: Composite having voids in a component [e.g., porous, cellular, etc.] - E01C: CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR (forming roads or like surfaces by compacting or grading snow or ice E01H) - D10B: INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract An underlayment layer is configured to support an artificial turf assembly. The underlayment layer comprises a core with a top side and a bottom side. The top side has a plurality of spaced apart, upwardly oriented projections that define channels suitable for water flow along the top side of the core when the underlayment layer is positioned beneath an overlying artificial turf assembly. ## Claims ### Claim 1 A turf underlayment layer having panels including a top side having a plurality of projections, a bottom side having a plurality of projections, and panel edges, the plurality of top side projections forming top side channels and the bottom side projections forming bottom side channels, the panel edges configured to abut edges of adjacent panels, the panels further including a plurality of drain holes dispersed over the panel surfaces for fluid communication between the top side and the bottom side of the panel, the drain holes positioned to intersect both the top side and bottom side channels to connect the top side channels to the bottom side channels, wherein the panels are made from a plurality of polyolefin beads, the plurality of polyolefin beads bonded together by at least one of pressure and heat to produce a substantially water-impervious surface. ### Claim 2 (depends on 1) The underlayment layer of claim 1 wherein the top side projections and bottom side projections terminate in generally flat support surfaces having different sized support surface areas, the top side projections and bottom side projections being spaced apart and sized such that the top side channels intersect with the bottom side channels at the drain holes. ### Claim 3 (depends on 2) The underlayment layer of claim 2 wherein the support surfaces of the top side projections are truncated cones having a friction enhancing surface configured as one of bumps, raised nibs, ribs, and dots. ### Claim 4 (depends on 3) The underlayment layer of claim 3 wherein the friction enhancing surface is a plurality of raised dots that are recessed and encircled with a rim. ### Claim 5 (depends on 2) The underlayment layer of claim 2 wherein the underlayment layer supports an artificial turf assembly that includes infill constituent particles and the top side channels impede the flow of infill constituent particles along the upper surface. ### Claim 6 (depends on 5) The underlayment layer of claim 5 wherein the top side channels include one of a dam and a roughened surface texture to impede the flow of infill constituent particles. ### Claim 7 (depends on 5) The underlayment layer of claim 5 wherein the top side projections have tapered sides that form the top side channels, the projections being arranged in a relatively spaced-apart relationship such that the channels form a narrowed part between adjacent projections, with the narrowed part functioning to impede the flow of infill constituent particles. ### Claim 8 (depends on 1) The underlayment layer of claim 1 wherein the bottom side projections have a larger surface area and a shorter projection height than the top side projections such that the top side projections deform more under load and return to a substantially similar condition at a slower rate than the bottom side projections. ### Claim 9 (depends on 1) The underlayment layer of claim 1 wherein the top side channels and bottom side channels accommodate up to 70 mm/hr rainfall on slope of about 0.5%. ### Claim 10 (depends on 9) The underlayment layer of claim 9 wherein the top and bottom side channels cooperate to provide about a 35 meter horizontal drainage distance and at least about a 175 millimeter perimeter head pressure. ### Claim 11 (depends on 8) The underlayment layer of claim 8 wherein the panels support an artificial turf assembly and the panel includes a core section between the top side projections and the bottom side projections, the top side projections defining a first deformation characteristic associated with an athletic response characteristic and the core defining a second deformation characteristic associated with a bodily impact characteristic, the first and second deformation characteristics being complimentary to provide a turf system bodily impact characteristic and a turf system athletic response characteristic. ### Claim 12 (depends on 11) The underlayment layer of claim 11 wherein the turf system athletic response characteristic provides a turf system shock attenuation of between 60% and 70% of the artificial turf system during running heel and running forefoot loads. ### Claim 13 (depends on 12) The underlayment layer of claim 12 wherein the second deformation characteristic provides an impact energy absorption sufficient to establish a head injury criteria of less than 1000. ### Claim 14 (depends on 11) The underlayment layer of claim 11 where the first deformation characteristic is responsive to a panel thickness and a molded material density. ### Claim 15 (depends on 14) The underlayment layer of claim 14 where the panel thickness is in a range of 20-30 millimeters and the molded material density is in a range of 50-70 grams per liter. ### Claim 16 (depends on 15) The underlayment layer of claim 15 wherein the top side channels and bottom side channels accommodate up to 70 mm/hr rainfall on a slope of about 0.5%. ### Claim 17 (depends on 15) The underlayment layer of claim 15 wherein the top and bottom side channels cooperate to provide about a 35 meter horizontal drainage distance and at least about a 175 millimeter perimeter head pressure. ### Claim 18 A turf underlayment layer having panels including a top side having a plurality of projections, a bottom side having a plurality of projections, the top side projections and bottom side projections terminating in generally flat support surfaces having different sized support surface areas, and panel edges, the plurality of top side projections forming top side channels and the bottom side projections forming bottom side channels, the panel edges abutting edges of adjacent panels, the panels further including a plurality of drain holes dispersed over the panel surfaces for fluid communication between the top side and the bottom side of the panel, the top side projections and bottom side projections being spaced apart and sized such that the top side channels intersect with the bottom side channels at the drain holes, the drain holes positioned to intersect both the top side and bottom side channels to connect the top side channels to the bottom side channels, the top side channels including a roughened surface texture. ### Claim 19 (depends on 18) The turf underlayment layer of claim 18 wherein the roughened surface texture is formed from a plurality of raised dots positioned on the top side channel. ### Claim 20 (depends on 19) The turf underlayment layer of claim 19 wherein the panels are formed from a molded, expanded bead polyolefin material. ### Claim 21 (depends on 20) The turf underlayment layer of claim 20 wherein the panels have a thickness in a range of 20-30 millimeters. ### Claim 22 (depends on 20) The turf underlayment layer of claim 20 wherein the panels have a molded material density in a range of 50-70 grams per liter. ### Claim 23 (depends on 22) The turf underlayment layer of claim 22 wherein the polyolefin material is one of a polyethylene material and a polypropylene material. ### Claim 24 (depends on 18) The turf underlayment layer of claim 18 wherein the top side projections have a smaller surface area than the bottom side projections.