Fiber reinforced raised pavement marker and method of making
AssigneeMinnesota Mining and Manufacturing Commpany
InventorsSithya S. Khieu, David C. May
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Abstract
A fiber-reinforced raised pavement marker made of a composite material comprising an isotropic mixture of a polymeric material, reinforcing fibers and a filler material. The results of finite element analysis and composite technology have been combined to produce a pavement marker having high flexural strength and impact resistance without the need for an impact-resistant shell. Durable, high strength composite pavement markers are made by casting a homogenous mixture of chopped glass fibers and a filler material in a polymeric matrix. Placement of a retroreflective lens within the mold followed by pouring and curing the composite material results in a finished product upon release from the mold.
Claims28
A fiber-reinforced pavement marker comprising a freestanding composite material that is configured in the form of a pavement marker and that comprises an isotropic mixture of a polymeric material, reinforcing fibers and a filler material, the fiber reinforced pavement marker having an apparent flexural modulus of at least 80,000 psi.
A pavement marker comprising a freestanding composite structure having first and second opposed end faces, first and second opposed side faces, an upper face, and a bottom surface;
- and having mounted on said freestanding composite structure a plastic crossmember extending from said first to said second opposed end faces, said plastic crossmember having a retroreflective lens disposed therein.
A fiber-reinforced pavement marker comprising a composite material, said composite material comprising an isotropic mixture of 30% to 76% polymeric material, 4% to 6% glass fibers, and 20% to 66% filler material, wherein percentages are weight percent of the total composite material.
A method of making a fiber-reinforced pavement marker comprising the steps:
- casting a homogeneous mixture comprising polymeric material reinforcing fibers and filler material in a mold to form a cast composite material hardened in the shape of a raised pavement marker;
- and then removing the resulting cast, raised pavement marker from the mold.
Dependencies are inferred from the claim text.