Patent Publication Number: US-10781563-B2

Title: Hydrodemolition system

Description:
FIELD OF THE INVENTION 
     This invention relates to hydrodemolition. In particular, this invention relates to a method and apparatus for the hydrodemolition of inclined surfaces, such as the walls of dams and spillways. 
     BACKGROUND OF THE INVENTION 
     It is known to use hydrodemolition to scarify surfaces, such as the walls of dams and spillways. One such approach is disclosed in U.S. patent application Ser. No. 14/746,348 to MacNeil et al., commonly owned with the present application. MacNeil et al. describes a method of hydrodemolishing the surface of an inclined wall that employs a rig suspended by cables from a staging platform that also leans on and rides on the wall that is to be worked. The rig comprises various machinery, including movable hydrodemolition nozzles to hydrodemolish a portion of the wall within a footprint of the rig. Once that portion has been hydrodemolished, the rig may be moved to another position on the wall so that another portion of the wall may be hydrodemolished. 
     Upward and downward movement of the rig along the wall may be achieved through rollers located generally at the corners of the rig. The rig may be mounted on rails, or alternatively it is possible to provide wheels to roll directly over the surface of the wall. 
     One issue that may arise depending on the degree of inclination of the wall is that the rig becomes inclined with the wall. If the rig is top-heavy, there is a risk that the rig may topple over if the incline is too severe. 
     Where the rig rolls directly over the surface of the wall, the rig may also become uneven when it straddles a portion of the wall whose surface has already been hydrodemolished. As a result, the orientation of the nozzles to the surface may no longer be optimized and will be inconsistent as compared to a pass of the rig where no straddling was involved. 
     It is therefore an object of the present invention to provide an effective way of accommodating the incline of the wall during hydrodemolition and of providing stability for the rig. Those and other objects will be better understood by reference to the detailed description of the preferred embodiment which follows. Not all of the objects are necessarily met by all embodiments of the invention described below or by the invention defined by each of the claims. 
     SUMMARY OF THE INVENTION 
     According to a particular embodiment of the present invention, the rig comprises wheels or rollers that may be selectively extended. As a result, the overall inclination of the rig may be adjusted with respect to the underlying surface, or the inclination may be adjusted to compensate for one side of the rig riding on a portion of the wall that has already been hydrodemolished to a certain depth. 
     According to one embodiment of the invention, a hydrodemolition rig for an inclined surface comprises a frame, a carriage, and a plurality of wheel assemblies spaced from one another about the frame. The carriage is configured to reciprocate within the frame and to carry one or more nozzles for delivering water to hydrodemolish the surface underlying the frame. The plurality of wheel assemblies supports the frame on the surface, with at least two of the wheel assemblies comprising a wheel and a hydraulic assembly for selectively adjusting the spacing between the wheel and the frame. 
     In a further embodiment, the wheel assemblies are located on a periphery of the frame. 
     In yet a further embodiment, the frame comprises a lower frame, an upper frame, and a track assembly between the lower frame and the upper frame. 
     In still yet a further embodiment, the lower frame comprises two spaced side members, wherein each of the hydraulic assemblies is connected to one of the side members. 
     In another embodiment, the track assembly comprises at least two tracks connected to the lower frame and extending a width of the frame. 
     In yet another embodiment, the carriage is adapted to move along the tracks. 
     In still yet another embodiment, the upper frame comprises a plurality of legs extending from one of the lower frame or the track assembly and an upper platform supported by the legs. 
     In another embodiment, the upper frame comprises a plurality of upper roller and the track assembly comprises a plurality of lower rollers. 
     In yet another embodiment, the hydrodemolition rig further comprises a belt extending around the upper rollers and the lower rollers. 
     In still yet another embodiment, the belt is connected to the carriage. 
     In a further embodiment, each of the hydraulic assemblies comprises an axle, an arm, and a hydraulic cylinder. The axle is attached to the respective wheel of the respective wheel assembly. The arm comprises first and second arm ends, wherein the arm is rotationally connected to the axle proximate to the first arm end and wherein the arm is pivotably connected to the lower frame proximate to the second arm end. The hydraulic cylinder comprises first and second cylinder ends, wherein the hydraulic cylinder is pivotably connected to the arm proximate to the first cylinder end and wherein the hydraulic cylinder is pivotably connected to the lower frame proximate to the second cylinder end. 
     In yet a further embodiment, the lower frame comprises one or more brackets extending from the side members. The hydraulic cylinder is pivotably connected to the lower frame proximate to the second cylinder end at one of the brackets. 
     In still yet a further embodiment, the hydraulic cylinder is adapted to extend or contract, thereby adjusting the height of the frame proximate to the location with respect to the respective wheel. 
     In still a further embodiment, the hydrodemolition rig comprises one or more ballast tanks attached to the frame. 
     In another embodiment, a hydrodemolition rig for an inclined surface comprises one or more nozzle assemblies for delivering water for hydrodemolishing the surface and a plurality of wheel assemblies. The wheel assemblies are at various locations on a periphery of the hydrodemolition rig, and each of the wheel assemblies comprises a wheel for travel along the surface and a hydraulic assembly connected to the wheel. The hydraulic assembly is adapted to adjust a height of the hydrodemolition rig proximate to the respective location with respect to the wheel. The hydraulic assemblies are configured to increase or decrease the height proximate to their respective locations. 
     In still another embodiment, the one or more nozzle assemblies comprise one or more nozzles. 
     In yet another embodiment, a method of hydrodemolishing a surface of a wall comprises the steps of providing a hydrodemolition rig comprising a frame and a plurality of wheel assemblies, each of the wheel assemblies comprising a wheel and a hydraulic assembly connected to the wheel and to a location on the frame, the hydraulic assembly adapted to adjust a height of the frame proximate to the location with respect to the wheel; adjusting a tilt of the frame by adjusting the heights at the respective locations through the respective hydraulic assemblies; and delivering water from one or more nozzle assemblies on the hydrodemolition rig to the surface for hydrodemolition. 
     In still yet another embodiment, the step of adjusting, for each of the one or more of the hydraulic assemblies, the heights at those respective locations comprises extending or contracting a hydraulic cylinder connected to the wheel and to the frame. 
     The foregoing may cover only some of the aspects of the invention. Other and sometimes more particular aspects of the invention will be appreciated by reference to the following description of at least one preferred mode for carrying out the invention in terms of one or more examples. The following mode(s) for carrying out the invention are not a definition of the invention itself, but are only example(s) that embody the inventive features of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described by reference to the detailed description of the preferred embodiment and to the drawings thereof in which: 
         FIG. 1  is a perspective view of the system according to the preferred embodiment of the invention, mounted on the wall to be hydrodemolished, showing a conceptualized version of the hydrodemolition rig; 
         FIG. 2  is a top view of the system of  FIG. 1 ; 
         FIG. 3  is a front perspective view of the hydrodemolition rig of the preferred embodiment; 
         FIG. 4  is a rear perspective view of the hydrodemolition rig; 
         FIG. 5  is a rear view of the hydrodemolition rig; 
         FIG. 6  is a side view of the hydrodemolition rig; 
         FIG. 7  is a partial exploded view of the hydrodemolition rig; 
         FIG. 8  is a partial view showing the wheel assembly of the hydrodemolition rig; 
         FIG. 9  is a side view of the wheel assembly of  FIG. 8 ; and 
         FIGS. 10 a , 10 b , and 10 c    show the levelling of the hydrodemolition rig. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 1 and 2 , a surface  10  to be hydrodemolished may comprise a wall  12  extending hundreds of feet in width and/or height. A suspension staging platform  14  may be provided to extend transversely along the width of the wall  12 , above the region of the wall  12  that is to be hydrodemolished. A hydrodemolition rig  100  may be suspended from the staging platform  14  to overlie an area of the wall  12  by means of a cable winch system  16  that is mounted on the staging platform  14  and that is transversely movable along the staging platform  14  by a trolley  20 . The rig  100  is suspended by cables  18 . 
     According to this embodiment, the trolley  20  will preferably be initially located proximate to one end of the staging platform  14 . Using the cable winch system  16 , the rig  100  may be moved up and/or down along the incline direction of the wall  12  (along direction A in  FIG. 2 ) below the staging platform  14 . As the rig  100  travels along the wall  12 , a portion of the wall  12  under the rig  100  is simultaneously hydrodemolished. In this manner, a vertical portion  22   a  of the wall  12  may be hydrodemolished as the rig  100  travels up and/or down the wall  12 . The hydrodemolition removes the top layer of the surface of the wall to a certain depth, for example several inches. 
     After the rig  100  has completely hydrodemolishing the vertical section  22 , the rig  100  may be moved transversely along the staging platform  14  (along direction B in  FIG. 2 ) by the trolley  20  for further hydrodemolition of the wall  12 . The rig  100  may again be moved up and/or down along the incline direction of the wall  12  below the staging platform in order to hydrodemolish another vertical portion  22   b  of the wall  12 . Preferably, the transverse displacement of the rig  100  is such that vertical portions  22   a ,  22   b  overlap (as shown in  FIG. 2 ), thereby forming a continuous hydrodemolished portion of the wall  12 . As a result, the rig  100  will straddle a portion of the wall that has already been hydrodemolished and a portion that has not. After vertical portion  22   b  has been hydrodemolished, the rig  100  may be further moved transversely along the staging platform  14  to continue hydrodemolition of the wall  12 . In this manner, a large continuous portion of the wall  12  may be hydrodemolished in a systematic approach. 
     Referring to  FIGS. 3 to 7 , the rig  100  comprises a frame  102  supported by a plurality of wheel assemblies  104 . Preferably, the wheel assemblies  104  are located on a periphery of the frame  102 , such as at the corners of the frame  102 , as shown in  FIGS. 3 and 4 . However, the wheel assemblies  104  may also be located at other positions along the frame  102 . The wheel assemblies  104  allow the rig  100  to travel along the wall  12 . 
     Referring to  FIG. 7 , the frame  102  comprises a lower frame  106 , an upper frame  108 , and a track assembly  110 . The lower frame  106  comprises spaced side members  112 ,  114 , with front and rear cross members  116 ,  118  extending between the side members  112 ,  114 . The wheel assemblies  104  may be secured to the side members  112 ,  114  in a manner as discussed below. 
     The track assembly  110  comprises a pair of tracks  120 ,  122  that preferably extend for the width of the frame  102 . The tracks  120 ,  122  are attached to the lower frame  106 , with the track  120  preferably attached to the front cross member  116  and the track  122  preferably attached to a lower support member  128  on the lower frame  106 . The tracks  120 ,  122  support a carriage  146  (see  FIG. 2 ) comprising one or more nozzle assemblies  124  for discharging water towards the bottom of the rig  100  in order to hydrodemolish the underlying surface of the wall  12 . 
     The upper frame  108  comprises legs  130  extending from either the track assembly  110  or the lower frame  106 . The legs  130  support an upper platform  132  that is spaced above the track assembly  110 . The upper platform  132  preferably comprises upper cross members  134  extending across a width of the rig  100  and upper support members  136  extending between the upper cross members  134 . 
     The carriage  146  is able to move along the tracks  120 ,  122  through carriage wheels  182 . In doing so, the nozzle assemblies  124  can be moved along a width of the rig  100  to hydrodemolish the surface of the wall  12  underlying the rig  100 . Preferably, each of the nozzle assemblies  124  comprises one or more nozzles  174  for directing water from the rig  100  towards the wall  12  for hydrodemolition. All of the nozzle assemblies  124  are connected to a hose  176  that delivers water from a water source to the nozzle assemblies  124 . Once the water reaches the nozzle assemblies  124 , the water is released from the nozzle assemblies  124  through the nozzles  174 . 
     The water from the nozzles  174  is released for hydrodemolition under pressure. As such, when the water impacts the surface of the wall  12 , some of the water may splash back against the underside of the rig  100 . In order to shield the interior of the rig  100  from any such splashes, a belt mechanism is preferably provided. Upper rollers  138  are provided on the upper platform  132 , proximate to the ends of the upper cross members  134 . Lower rollers  140  are similarly provided on the track assembly  110 , proximate to the ends of the tracks  120 ,  122 . The locations of the upper and lower rollers  138 ,  140  generally form the corners of a polygon, when viewed from the front of the rig  100 . A belt  142  extends around the upper and lower rollers  138 ,  140 , forming the perimeter of the polygon. 
     The carriage  146  is preferably attached to the belt  142 , such that movement of the carriage  146  along the tracks  120 ,  122  will cause movement of the belt  142 . The belt  142  is able to shield at least a portion of the underside of the rig  100  from any water splashing back from the surface of the wall  12 . 
     Referring again to  FIGS. 3 to 6 , one or more of the wheel assemblies  104  are connected to the lower frame  106  as described below. Each of the wheel assemblies  104  comprises a wheel  105  and a hydraulic assembly  148 . Referring to  FIGS. 8 and 9 , the hydraulic assembly  148  comprises an axle  150  for attachment to the wheel  105 , an arm  152 , and a hydraulic cylinder  160 . The axle  150  is rotationally attached to the arm  152 , which is pivotably attached to the side members  112 ,  114  of the lower frame  106 . The attachment of the arm  152  to the side members  112 ,  114  may be through a pin  166  that is rigidly connected to the side members  112 ,  114  but still allows for pivotable movement of the arm  152  with respect to the side members  112 ,  114 . A bracket  154  is preferably provided on the lower frame  106  that is rigidly connected to the side members  112 ,  114 . Preferably, the arm  152  comprises first and second arm ends  156 ,  158 . The axle  150  may be connected to the arm  152  proximate to the first arm end  156 , while the side members  112 ,  114  may be connected to the arm  152  proximate to the second arm end  158 . The hydraulic cylinder  160 , comprising first and second cylinder ends  162 ,  164 , extends between the arm  152  and the bracket  154 . Preferably, the arm  152  is pivotably attached to the hydraulic cylinder  160  proximate to the first cylinder end  162 , while the hydraulic cylinder  160  is pivotably attached to the bracket  154  proximate to the second cylinder end  164 . 
     Through this arrangement, any extension or retraction of the hydraulic cylinder  160  will cause the arm  152  to pivot with respect to the side members  112 ,  114 , which will in turn result in a general overall upward or downward displacement of the axle  150  and the wheel  105 . This results in a tilting of the rig  100  in relation to the underlying surface of the wall  12 . 
     Referring again to  FIGS. 1 and 2 , when the rig  100  has completed hydrodemolition of the vertical portion  22   a , the rig  100  is preferably moved transversely along the staging platform  14  to begin hydrodemolition of the vertical portion  22   b . In the case where vertical portions  22   a ,  22   b  overlap, after the rig  100  has been moved transversely along the staging platform  14 , all of the wheels  105  may not be level with one another because of the fact that the rig straddles portions of the wall of different depths (the hydrodemolished surface being deeper than the surface yet to be treated). For example, referring to  FIGS. 10 a , 10 b , and 10 c   , if vertical portion  22   a  has been hydrodemolished (but vertical portion  22   b  has not yet been hydrodemolished), then after rig  100  has been moved transversely, the wheels  105  on side member  112  may sit within the (hydrodemolished) vertical portion  22   a , while the wheels  105  on side member  114  may sit within the (non-hydrodemolished) vertical portion  22   b . Therefore, the rig  100  will be tilted or inclined towards side member  112 , resulting in the rig  100  no longer being generally parallel to the overall incline of the wall  12 . 
     If the rig  100  is not generally parallel to the overall incline of the wall  12 , then the water discharged from the nozzles  174  may not impact the surface of the wall  12  at an optimal angle. This can be mitigated by adjusting the tilt of the rig  100  so that its frame remains substantially parallel to the surface of the wall  12  that has not yet been hydrodemolished. This can be achieved by selectively actuating the hydraulic cylinders  160  of the hydraulic assemblies  148  for the appropriate wheels. 
     For example, in the arrangement shown in  FIGS. 8 and 9 , when the hydraulic cylinder  160  is extended, this will result in the arm  152  pivoting in a generally downward direction (with respect to the side members  112 ,  114 ). This downward movement of the arm  152  will have the effect of raising the portion of the side members  112 ,  114  generally proximate to the bracket  154  (which in turn will result in that region of the rig  100  being raised). Conversely, when the hydraulic cylinder  160  is retracted, the arm  152  will pivot in a generally upward direction. This upward movement of the arm  52  will have the effect of lowering the portion of the side members  112 ,  114  generally proximate to the bracket  154 , relative to the rest of the frame  102 . 
     Referring to  FIG. 10 a   , when the rig  100  has completed hydrodemolition of a portion of the wall  12  (e.g. vertical section  22   a ), that portion is generally depressed with respect to the rest of the wall  12 . When the rig  100  is moved transversely to hydrodemolish another portion of the wall  12  (e.g. vertical section  22   b ), the rig  100  may no longer be sitting on a section of the wall  12  that is generally flat (e.g. the wheels  105  on side member  112  sit within a hydrodemolished section while the wheels  105  on side member  114  sit within a non-hydrodemolished section). The rig  100 , including the frame  102 , would generally not be parallel to the overall incline of the wall  12 , as shown in  FIG. 10 b   . However, by coordinating the movement of the various axles  150  and wheels  105 , it is possible to adjust the posture of the rig  100  so that the incline of the rig  100  matches, or at least approaches, the overall incline of the wall  12 . 
     In the example above, this may require, for example, that the hydraulic cylinders  160  of the hydraulic assemblies  148  located on side member  112  be extended, thereby raising side member  112 . Depending on the degree of tilt of the rig  100 , this may also require that the hydraulic cylinders  160  of the hydraulic assemblies  148  located side member  114  be retracted, thereby lowering side member  114 , as shown in  FIG. 10 c   . By coordinating the extension of the hydraulic cylinders  160 , it is possible to adjust the relative heights of side members  112 ,  114  and in doing so, adjust the tilt of the frame  102  and the rig  100 . 
     The rig  100  may also comprise one or more ballast tanks  172  positioned at locations on the lower frame  106  in order to improve the overall stability of the rig  100  and to prevent the rig  100  from accidentally tipping over. 
     It will be appreciated that other constructional details may also be varied as required to achieve the objects of the invention.