Abstract:
A pre-cast textured tile system and method for positioning on walkways, crosswalks and other areas of pedestrian traffic for providing direction and warning to visually handicapped persons. The tile may be made for embedding in fresh concrete on a walking surface and have a substantially planar piece with a top surface and a bottom surface, the top surface having a plurality of raised elements and the bottom surface being sterified. A number of the tiles may be aligned so as to easily adapt to a number of different shapes and purposes. The tiles are not interconnected, but rather abut one another with at least one edge being flush to the walking surface.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention generally relates pedestrian platforms, walkways and sidewalks and more particularly to pedestrian platforms, walkways and sidewalks for the blind and visually impaired.  
           [0002]    There is often the need, in public transit facilities, for pedestrians to detect the location of a platform or other potential hazards. By making the pedestrian aware of a potential hazard, they may avoid the hazard. By way of example, this may include railroad crossings, subway platforms, loading docks, stages, stairways, sidewalks, curb ramps, crosswalks, man holes, potholes, etc.  
           [0003]    Americans with Disabilities Act (ADA): “Accessibility Guidelines for Buildings and Facilities” set the requirements for the use of detectable warnings at curb ramps, walking surfaces, transit platforms and the like to warn visually impaired people of hazards. The guidelines require that detectable warnings shall consist of truncated domes with a diameter of nominal 0.9″ (23 mm), a height of nominal 0.2″ (5 mm) and a center-to-center spacing of nominal 2.35″ (60 mm) and shall contrast visually with adjoining surfaces, either light on dark or dark on light. The material used to provide contrast shall be an integral part of the walking surface. Detectable warnings use on interior surfaces are required to differ from adjoining surfaces in resiliency or sound-on-cane contact. Platform edges bordering a drop off and not protected by screens or guard rails shall have a detectable warning 24 inches wide running the full length of the platform drop off. If a walkway crosses or adjoins a vehicular way, and the walking surface is not separated by curbs, railing or other element between the pedestrian areas and the vehicular areas, the boundary between such area is to be defined by a continuous detectable warning 36 inches wide. Curb ramps are also required to have detectable warnings extending the full width and depth of the curb ramp.  
           [0004]    Known within the art are tiles designed to be glued or mechanically fastened to the existing walking surface. U.S. Pat. No. 4,715,743 issued to Schmanski discloses a uniform adhesive layer applied to a tile, which is then adhered to a surface. Tiles installed according to this method are not flush with the ground and may come undone.  
           [0005]    Also known within the art is the use of a patterned tool to produce a durable tactile warning surface for sidewalks and other walkways including pouring a concrete base, applying pigmented or colored hardener to the upper surface of the concrete base and stamping the upper surface of the converter base with a patterned tool. This can be very costly, incurring labor costs due to the waiting periods between pouring and stamping and the requirement of on-site labor to perform the stamping. Also, there is a great deal of room for imperfections and error.  
           [0006]    Adherence of the tile to a walkway surface is a critical aspect of the present invention. Prior efforts to retain the tile in an attached position have been frustrated by separation of the peripheral edge of the tile from the pavement. Prior attempts to solve this problem have included the stamping of concrete, plastic tiles with chamfered edges and the like. However, as discussed previously, stamping is costly, prone to errors, labor intensive and requires on site work. Plastic tiles are much more fragile and subject to lifting and coming undone.  
           [0007]    Accordingly, what is needed is a textured tile system and method of installation that allows for pre-cast tiles to be easily installed, that abut the edge of the walking surface, do not require labor intensive on-site stamping, provides fewer imperfections, is in compliance with the ADA and may freely move relative to one another.  
         SUMMARY OF THE INVENTION  
         [0008]    The present invention provides tiles and a method of installing textured tiles which can be embedded in freshly poured cement at a walking surface and pre-cast in concrete. The textured tiles may be installed and incorporated into a surface so as to provide visual and tactile warnings. This may be particularly useful to disabled individuals and in particular the visually impaired.  
           [0009]    According to one aspect of the present invention, a pre-cast textured tile for embedding in fresh concrete on a walking surface is disclosed comprising a substantially planar piece with a top surface and a bottom surface. The top surface having a plurality of raised elements and the bottom surface being sterified.  
           [0010]    According to yet another aspect of the present invention, a pre-cast tile system is disclosed for use on a walking surface for providing direction and warning to visually handicapped persons. The pre-cast tile system may be comprised of a multitude of substantially rectangular planar pieces with a top surface and a bottom surface. The top surface having a plurality of raised elements projecting upward therefrom and being configured as a truncated dome structure and the bottom surface being sterified. There may also be a multitude of substantially angled planar cut pieces with a top surface and a bottom surface, the top surface having a plurality of raised element projecting upward therefrom and being configured as a truncated dome structure and the bottom surface being sterified. The substantially angled planar cut pieces and the substantially rectangular planar pieces may be placed together so as to form a walking surface which is flush to the edge of a walking surface.  
           [0011]    According to yet another aspect of the present invention, a method of producing a textured warning surface of a sidewalk is disclosed comprising the steps of preparing a concrete mix suitable for pouring the concrete mix into a receiving form, wherein the receiving form has a raised pattern embedded therein; adding coloring agent to form a concrete mix; pouring the concrete mix into the form; scarifying the bottom surface of the concrete mix; allowing the concrete mix to cure forming a textured warning surface, wherein the textured warning surface has a plurality of raised elements formed on a top surface and the textured warning surface is scarified on a bottom surface; and sealing the top surface.  
           [0012]    These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 depicts an elevational view according to the present invention;  
         [0014]    [0014]FIG. 2 depicts a system according to the present invention;  
         [0015]    [0015]FIG. 3 depicts a system according to the present invention;  
         [0016]    [0016]FIG. 4 depicts a method according to the present invention;  
         [0017]    [0017]FIG. 5 depicts a method according to the present invention;  
         [0018]    [0018]FIG. 6 depicts form according to the present invention;  
         [0019]    [0019]FIG. 7 is a side view according to the present invention; and  
         [0020]    [0020]FIG. 8 is a view top view of the bottom side of a textured tile according to the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]    The present invention may be used as a detectable warning to individuals, and in particular visually impaired individuals against potential hazards. Also, the present invention is intended to provide a highly efficient method of bringing present sidewalks and walking surfaces to compliance with the requirements of the ADA Accessibility Guidelines. It is envisioned that the tiles may be applied to any area where a detectable warning is desired including loading docks, stages, subway platforms, speaking platforms, stairway tops, landings, docks, pools, piers, steep slopes, curbs, potholes, restricted areas, manholes and the like. Also, as the language of detectable warnings progresses, it is intended that the top surface of the present invention may be patterned accordingly. For instance, the top portion of the concrete may have raised bars or other patterns known within the art to serve the purpose of directing or informing those with disabilities.  
         [0022]    As shown in FIG. 1, a pre-cast textured tile  10  made for embedding in fresh concrete on a walking surface comprising a substantially planar piece with a top surface and a bottom surface, the top surface having a plurality of raised elements and the bottom surface being sterified. The raised element may be a truncated dome, and be between 0.2 and 1 inches above the surface of the tile.  
         [0023]    A pre-cast tile system is shown in FIG. 2, for use on a walking surface for providing direction and warning to visually handicapped persons. The pre-cast tile system comprising a multitude of substantially rectangular planar pieces  20  with a top surface  22  and a bottom surface (not shown), the top surface  22  having a plurality of raised elements  14  projecting upward therefrom and being configured as a truncated dome structure. The bottom surface (not shown) is sterified. There may also be a multitude of substantially angled planar cut pieces  24  with a top surface  26  and a bottom surface (not shown). The top surface  26  having a plurality of raised elements  14  projecting upward therefrom and being configured as a truncated dome structure and the bottom surface (not shown) being sterified. The substantially angled planar cut pieces  24  and the substantially rectangular planar pieces  22  are placed together so as to form a walking surface which is flush to the edge  30  of a surface. At least one edge of the substantially angled planar cut pieces  24  abuts at least one edge of the substantially rectangular planar pieces  20 . According to the embodiment depicted in FIG. 2, the surface is a curb.  
         [0024]    At least one edge of the substantially angled planar cut pieces  24  may be flush with a walking surface. According to another embodiment, at least one edge of the substantially rectangular planar pieces  22  may be flush with a walking surface.  
         [0025]    According to the embodiment depicted in FIG. 2, a multitude of substantially rectangular planar  22  pieces each have two opposite side edges (by way of example,  50  and  52 ) intended for alignment with corresponding side edges of other tiles, and front edge  58  and rear edges  56  at least one of which is a traffic facing edge  58 , in which raised elements  14  adjacent the traffic facing edge are lower in height than raised element  14  elsewhere on the tile. The tile thus having raised elements of a gradual height increase. It should be understood that the raised elements may be of uniform height or vary, without departing from the present invention.  
         [0026]    [0026]FIG. 3 depicts a manner in which the shaped may be properly fitted to any area. As shown, the pre-cast tiles  70  may be cut along a line  72  which corresponds in shape to the curb  74 . The cut portion  76  may then be removed and placed into the area  78 . In this way, the exact shape may be tailored on site.  
         [0027]    According to another embodiment, a method of producing a textured warning surface of a sidewalk is disclosed the method comprising: preparing a concrete mix suitable for pouring into a receiving form  100 , wherein the receiving form has a raised pattern embedded therein; optionally, coating said form with a release agent  101 ; adding coloring agent  102  to form a concrete mix; optionally adding a hardener  103 ; optionally adding a pouring the concrete mix into the form  104 ; scarifying the bottom surface of the concrete mix  106 ; allowing the concrete mix to cure forming the textured tile  108 , wherein the textured tile has a plurality of raised elements formed on a top surface and the textured tile is scarified on a bottom surface; optionally, the process (steps  104 - 108 ) may be repeated  110  to produce a multitude of tiles; and sealing the top surface ( 112 ). Optionally, a hardener may be applied to the concrete mix. The form may be a urethane pad and the raised pattern embedded therein may be a truncated dome.  
         [0028]    According to the embodiment, wherein a multitude of textured tiles are form by repeating  110  steps  104  to  112 , the step  114  of aligning the textured tiles so that at least one edge of the multitude of textured tiles is flush to a surface. At least one tile may be a substantially rectangular planar piece with a top surface, bottom surface, and at least three edges. The top surface having a plurality of raised elements projecting upward therefrom and being configured as a truncated dome structure. The bottom surface being sterified. At least one tile may be a substantially angled planar cut piece with a top surface, a bottom surface, and at least three edges. The top surface of the substantially angled planar cut piece having a plurality of raised elements projecting upward therefrom and being configured as a truncated dome structure and the bottom surface being sterified. At least one of the at least three edges of the substantially rectangular planar piece may be aligned with at least one of the at least three edges of the substantially angled planar cut piece.  
         [0029]    The concrete mix according to a preferred embodiment is a non-shrink grout blend of portland cements, admixtures, and aggregates. By way of example, this may be SIKA 212 or SYMONS NYSDOT non-shrink grout. This material is designed to provide high flexural, and compressive strength performance from damp pack to fluid consistencies. All surfaces in contact with the non-shrink grout should be free of dirt, oil, grease, laitance, and other contaminants. The temperature of contact areas should be maintained between 45° F.(7° C.) and 90° F. (32° C.) prior to grouting and during initial curing period.  
         [0030]    As shown in FIG. 5, a method of producing a textured tile system for use as a warning surface is disclosed, the method comprising: preparing a concrete mix suitable into a receiving form  150 , wherein the receiving form has a raised pattern embedded therein; optionally coating the form with a release agent  152 ; adding coloring agent to form a concrete mix  154 ; optionally adding a hardener  156 ; pouring the concrete mix into the form  158 ; scarifying the bottom surface of the concrete mix  160 ; allowing the concrete mix to cure forming the textured tile  162 , wherein the textured tile has a plurality of raised elements formed on a top surface and the textured tile is scarified on a bottom surface; sealing the top surface of the textured tile  164 ; pouring fresh concrete onto a surface  166 ; priming the bottom surface of the textured tiles with a binding agent  168 ; and placing the bottom surface of the textured tiles on fresh concrete  170 ; optionally, aligning a multitude of textured tiles in the fresh concrete  172 ; and aligning at least one edge so as to be flush with a surface  174 .  
         [0031]    As in the previous embodiments, the at least one tile may be a substantially rectangular planar piece with a top surface, bottom surface, and at least three edges, and at least one tile is a substantially angled planar cut pieces with a top surface, a bottom surface, and at least three edges. At least one of the at least three edges of the substantially rectangular planar piece may be aligned with at least one of the at least three edges of the substantially angled planar cut piece. At least one edge of at least one tile may be aligned so as to be flush with a surface. The surface may be any area where a detectable warning is desired including loading docks, stages, subway platforms, speaking platforms, stairway tops, landings, docks, pools, piers, steep slopes, curbs, potholes, restricted areas, manholes and the like.  
         [0032]    [0032]FIGS. 6 and 7 depict a form  300  according to the present invention. As shown, the form may have an inner height  310  of 1½″ and an outer height  304  of 2¼″. The form has inverted holes  308  which form the raised elements of the textured tiles. The height  310  may be between 0.05 and 5 inches, preferably one inch. It should be understood any dimensions would not depart from the present invention, these are merely preferred dimensions. According to a preferred embodiment, the forms are made using 2¼″×1½″ wood, screwed together with 2½″ sheetrock screws to form rectangles. The size and spacing of the truncated domes may not allow 12″×12″ sections. Therefore, sizes of sections range from 10⅞″×11⅝″ to 12⅜″×14⅝″. A set of 10 sections may complete a pattern that measures 5′×2′×1½″.  
         [0033]    A concrete mix is poured into the form  300  in the space  320  according to previously discussed methods. Although the terms cement and concrete often are used interchangeably, cement is actually an ingredient of concrete. Concrete is basically a mixture of aggregates and paste. The aggregates are sand and gravel or crushed stone; the paste is water and Portland cement. Concrete gets stronger as it gets older. According to a preferred embodiment of the present invention, non-shrink grout is used. However, any other cement or concrete known within the art, including portland cement may be utilized. Portland cement is not a brand name, but the generic term for the type of cement used in virtually all concrete. Cement comprises from 10 to 15 percent of the concrete mix, by volume. Through a process called hydration, the cement and water harden and bind the aggregates into a rocklike mass. This hardening process continues for years meaning that concrete gets stronger as it gets older. Because of this, it is desirable to use concrete rather than plastics or polymers. According to a preferred embodiment non-shrink grout is mixed with coloring agent and water and blended in a container using a mortar mixing blade attached to an electric drill until the desirable consistency is achieved. Typically, the color of the composition will be yellow and will conform to Federal Color No. 33538 of standard 595A. This particular yellow color is close to that final color detectable by visually handicapped persons prior to going totally blind.  
         [0034]    [0034]FIG. 8 depicts scarification. Once the concrete mix is poured, the bottom portion  350  may be scarified. This may be automated, or accomplished through the use of a scarifying tool  352 . Also, numbers  354  may be scarified into the bottom portion  350  of the concrete, so as to identify the proper tile for future reference to form a system of well aligned tiles. For example, where a multitude of tiles of different sizes need to be pre-cast for future use, such symbols may be utilized to identify the order in which this tile should be placed, or to depict standard sizes.  
         [0035]    Curing is one of the most important steps in concrete construction, because proper curing greatly increases concrete strength and durability. Concrete hardens as a result of hydration: the chemical reaction between cement and water. However, hydration occurs only if water is available and if the concrete&#39;s temperature stays within a suitable range. During the curing period-from five to seven days after placement for conventional concrete-the concrete surface needs to be kept moist to permit the hydration process. New concrete can be wet with soaking hoses, sprinklers or covered with wet burlap, or can be coated with commercially available curing compounds, which seal in moisture.  
         [0036]    Temperature extremes make it difficult to properly cure concrete. On hot days, too much water is lost by evaporation from newly placed concrete. If the temperature drops too close to freezing, hydration slows to nearly a standstill. Under these conditions, concrete ceases to gain strength and other desirable properties. In general, the temperature of new concrete should not be allowed to fall below 50 Fahrenheit (10 Celsius) during the curing period.  
         [0037]    After the mix has hardened, the section are removed and placed raised element side up or top side up, and each is sealed with a clear liquid sealer. The pieces may then be brought to a jobsite, or an area to be installed. They may be prefabricated or cut at the site to any shape. Concrete may be poured into to sidewalk and made to the proper grade. According to a preferred embodiment, the sidewalk concrete may be 606 lbs/cy, with 36.2 sand % solid volume, a water/cement weight of 0.46, a 6.5% air content, a slump range between 2.5 and 3.5 and a type CA 2 coarse aggregate gradation. The underside of each textured tile may be primed with a bonding agent, and the sections placed into fresh concrete. This may be according to numbers on the bottom side or according to professional installation. It is desirable that the pieces be individually places, rather than interlocked as they withstand temperature changes and not succumb to cracking, chipping or damage. Also, the individual placement accommodates the transition of the normal pitch of the sidewalk to the pitch of the curb.  
         [0038]    The following detailed description is of the best currently contemplated modes of carrying out the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.  
         [0039]    It should be understood, of course, that the foregoing relates to preferred embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims.