GB2035420A - Road breaking - Google Patents

Abstract

Tarmacadam or concrete road surfaces are broken by means of a horizontally acting ram driving a plough blade under the road surface. Alternatively the ram drives a claw grab to excavate a horizontal shaft under the road surface after which the concrete is snapped off by a road breaking portcullis. In a further embodiment the ram drives a multipoint road drill which is hammered home using pneumatic loading on the free end of the ram. <IMAGE>

Description

SPECIFICATION Hydraulic and/or pneumatic road breaking & trench cutting equipment for tarmacadam & concrete roads This equipment is based on the comparatively negligible tensile strength of tarmacadam hardcore and concrete compared to their compressive and shear strength.

Current practice is to compress and/or shear the surface from on top. This approach is to penetrate the subsoil below the hardcore bed, in a horizontal direction, and then to break the surface from below.

Embodiment no. 1 for tarmacadam This would entail a horizontally acting hydraulic ram with a "Plough Share" or "Shovel/Wedge" shaped nose. An initial hole cut by conventional methods to enable the ram nose to attack the vertical face as in Drawing No. 1 would be required.

Swivelied splay feet would lock into the side walls as the ram was moved forward.

Embodiment no.2 for concrete A horizontally acting hydraulic ram with claw grab (as in a "Back Acter" Tractor), see Drawing No. 2, which would excavate a horizontal shaft prior to the use of a road breaking "Portcullis", the concrete, being unsupported, would snap due to tensile failure rather than being compressed against the hardcore and subsoil.

Embodiment no. 3 for concrete Using the shaft cut in Embodiment No. 2, insert a multipoint road drill (see Drawing No. 3) which would be held in position hydraulically and hammered home using pneumatic loading on the free end of the ram. This would have the advantage of the drills reacting against the total weight of the road surface rather than against their own limited weight of 70 or 80 Ibs.

1. This invention is designed to break road surfaces by the use of lateral pressure on a ploughshare in the layer immediately below the surface of the road, acting against the tensile strength of the road surface.

2. As in Claim 1 this invention is designed to break road surfaces by attacking their weakest tensile strength area, by tunnelling below the surface and then cutting or snapping the surface with a "Pile Driver Portcullis".

3. This road breaking device is based on the principle that road drills acting from below would be: (a) Self clearing.

(b) More effective in action in working against the weight of the road slab rather than the drill itself.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (3)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Hydraulic and/or pneumatic road breaking & trench cutting equipment for tarmacadam & concrete roads This equipment is based on the comparatively negligible tensile strength of tarmacadam hardcore and concrete compared to their compressive and shear strength. Current practice is to compress and/or shear the surface from on top. This approach is to penetrate the subsoil below the hardcore bed, in a horizontal direction, and then to break the surface from below. Embodiment no. 1 for tarmacadam This would entail a horizontally acting hydraulic ram with a "Plough Share" or "Shovel/Wedge" shaped nose. An initial hole cut by conventional methods to enable the ram nose to attack the vertical face as in Drawing No. 1 would be required. Swivelied splay feet would lock into the side walls as the ram was moved forward. Embodiment no.2 for concrete A horizontally acting hydraulic ram with claw grab (as in a "Back Acter" Tractor), see Drawing No. 2, which would excavate a horizontal shaft prior to the use of a road breaking "Portcullis", the concrete, being unsupported, would snap due to tensile failure rather than being compressed against the hardcore and subsoil. Embodiment no. 3 for concrete Using the shaft cut in Embodiment No. 2, insert a multipoint road drill (see Drawing No. 3) which would be held in position hydraulically and hammered home using pneumatic loading on the free end of the ram. This would have the advantage of the drills reacting against the total weight of the road surface rather than against their own limited weight of 70 or 80 Ibs. CLAIMS

1. This invention is designed to break road surfaces by the use of lateral pressure on a ploughshare in the layer immediately below the surface of the road, acting against the tensile strength of the road surface.

2. As in Claim 1 this invention is designed to break road surfaces by attacking their weakest tensile strength area, by tunnelling below the surface and then cutting or snapping the surface with a "Pile Driver Portcullis".

3. This road breaking device is based on the principle that road drills acting from below would be: (a) Self clearing.

(b) More effective in action in working against the weight of the road slab rather than the drill itself.