Abstract: Interlocking blocks for the stabilization of stream and river banks and ct lines, road bed embankments, and boat ramps, are made of concrete, and have a high proportion of open area. Interlocking connections between adjacent blocks are made by radial projecting members and recesses on the periphery of each block, the projecting members of one block fitting into the recesses on adjacent blocks. Projections and recesses are alternately provided at regular angular intervals such that blocks can be assembled in either square or an equilateral triangular patterns. A layer of filter cloth material is laid on the sloping surface and upon which the blocks are then placed; this filter cloth slows down the leaching of water through the open areas between the interlocking blocks and prevents the washing away of sand and silt by stream or river water or rainwater runoff.

Abstract: In an apparatus for forming concrete pathways, a mold includes a plurality of openings for receiving concrete therein. The mold openings define separate and distinct concrete cavities. Concrete pathways, are formed by placing the mold of the invention on a surface for receiving the concrete in the concrete cavities. Upon removal of the mold, the concrete segments retain the shape of the mold cavities and are slightly separated from each other. The procedure is repeated to form a pathway of a desired length and configuration.

Abstract: A unitary paving block having an exposed surface in use having a multitude of markings to simulate individual, random paving elements has a periphery with a shape which enables the block to be laid with other similar blocks in an irregular, substantially unrepeated paving array. The shape of the periphery of the blocks is such that the blocks can be laid with each block angularly moved with respect to each other and/or laid in staggered relationship with respect to each other.

Abstract: A modular platform suitable for use as a portable roll-out walkway or floor comprising a plurality of interconnected treads of a lightweight molded or formed thermoplastic material, each of the treads comprising a top surface for supporting loads thereon, a ground-engaging bottom surface, and four side portions comprising two adjacent male side portions and two adjacent female side portions disposed between the bottom and top surfaces, the side portions comprising interconnecting member integral with the tread for selectively disengageable interconnection with adjacent treads to configure the platform in variable sizes as desired. The top surface comprises drainage apparatus to allow passage therethrough of air and water. The bottom surface comprises a plurality of ribs spaced so as to form cavities in cooperative relation with the drainage apparatus so as to disperse weight loads, allow passage thereto of water drained through the drainage apparatus, and maintain a moisture canopy underneath the treads.

Abstract: A method and apparatus for the construction of a two-layer flooring system for use at a construction site such as an oil well drilling site. The flooring system is particularly well suited for use in areas with dry, sandy soil. The flooring system is formed by interlocking both the ends and sides of a plurality of mat units. Each of the mat units includes two layers of boards. The first layer has end locking tabs extending beyond the edge of the first layer and corresponding end locking slots, formed by offsetting selected boards. The second layer similarly includes side locking tabs and corresponding side locking slots, also formed by offsetting selected boards. The arrangements of these tabs and slots is such that half-size units and inverted units may be utilized, allowing a wide variety of patterns of interlocking units to be utilized for the flooring system.

Abstract: Floor coverings of composite tiles having a polygonal ground plan and having elastic properties. A recess which is formed of a hollow space in the composite tiles can include a cylindrical support molded on the underside of the tiles. The walls of each composite tile can be stabilized by a supporting component which is connected to the vertical edges of the composite tiles and preferably extends to the lower edge of the tiles. Laying plates which include an arrangement designed to co-operate with the supports of the composite tiles can be used. The laying plates form a laying system which permits the laying of the composite tiles even on difficult substrates and provide for the laid composite tiles to be easily be lifted.

Abstract: A concrete construction system enabling the construction of multi-storey buildings using single storey wall panels and elevated flat slabs is provided. The invention provides a plurality of concrete panels of a uniform thickness, the plurality of concrete panels including wall and floor panels, wherein the floor panels are interconnected with abutting floor panels with a tongue and channel system so as to properly support the floor panels on the supporting wall.

Abstract: A revetment block for use in a revetment system, the block having top and bottom surfaces and pairs of opposed and substantially parallel side surfaces. One of the side surfaces in each of the opposed pairs has first and second projections and the other of the side surfaces in each of the opposed pairs has first and second recesses. The projections and recesses are sized and configured so that they mate with projections and recesses on the side surfaces of adjacent blocks. The bottom surface of the block may be provided with projections to enhance the frictional stability of the blocks. The blocks are connected together by cables which pass through tunnels between the side surfaces of the blocks. A sleeve fitted into each opening of the tunnel in the side surface is provided to protect the cables from breakage.

Abstract: A reusable mat system for constructing roadways and equipment support surfaces comprising a plurality of uniform individual mats which are constructed of lightweight composite materials and which include strengthening agents. The individual mats partially overlap and interlock to form a continuous and substantially smooth surface, to prevent undesired movement of the mats on location, and to permit quick installation of the mats by simple placement methods.

Abstract: A modular platform floor system for advantageous use at trade shows and conventions includes a plurality of interconnectable floor modules, wherein each module includes a supporting rectangular frame and a panel supported thereon, the platform having cutout, notched corners defining openings between two or more adjacently located floor modules, and plastic plugs which seat within these openings to interconnect the adjacently located modular units via downwardly depending prongs which engage the supporting frames of the modular units. Carpet pieces are secured separately to the top surfaces of the panels and to the plugs, to provide an aesthetic and comfortable surface for the floor. The plug is integrally formed, preferably of injection molded thermoplastic, to provide a unitary one piece plug for interconnecting the adjacently located floor modules.

Abstract: A four sided tile, particularly for paving, flooring or cladding includes a first side edge, a second slide edge parallel with shorter than the first side edge, and third and fourth side edges which are not parallel. The length of the shorter side edges is the same and the sum of their length is equal to the length of the larger side. The side edges are preferable curved with radii of equal length.

Abstract: All elements are designed in a modular manner on the base of a unitary length. They include elements comprising more than one square having side lengths a and a camfered edge b at an angle of 45.degree.. The elements, which can be produced in the form of paving stones, or thin ceramics tiles, or trough stones and can be laid out to create floor or wall coverings, allow to lay out all letters, numbers or common symbols, as well as a great variety of other figures, and to provide them with straight-lined borderings without the need of breaking, grinding or otherwise altering a single element. It is understood that said elements can be differently colored in order to emphasize them.

Abstract: A ground covering is provided by linking together individual elements; the elements each comprise a first portion and a second portion linked by a hinge allowing the connected elements to be rolled up in the form of a carpet for easy storage and transport.

Abstract: A paving stone configured to be arranged in a paving stone bond in an area-covering grid-shaped lattice of paving stones comprised of lattice elements. The paving stone has side walls and includes a plurality of spacers disposed on the side walls thereof. Each of the spacers has an abutting surface adapted to be positively joined to a respective abutting surface of a spacer on an adjacent paving stone in the lattice of paving stones. In this manner, a crossing joint is formed between the paving stones. The abutting surface of each of the spacers includes a stepped contour for positively meshing with a corresponding stepped contour on the respective abutting surface of the spacer on the adjacent paving stone, the plurality of spacers being disposed on the side walls of the paving stone such that the stepped contours of their respective abutting surfaces are identically oriented in either of two rotational directions defined around the side walls of the paving stone.

Abstract: A system of concrete blocks is provided for use as a revetment for preventing soil erosion in which individual blocks are sized and shaped to be cable interconnected to form a matrix or mats. The matrix or mat or blocks overlies and holds in place a layer of porous and permeable geo-textile overlying the protected soil area. The shape of the individual blocks is such as to permit growth of vegetation therethrough and to channel water flowing over the surface of the blocks to increase the downward pressure on the geo-textile layer.

Abstract: A railroad grade crossing system comprises a plurality of plates that rest on selected ties. The plates have two or more upstanding projections with threaded openings extending through them. The plates are positioned at the intersections of adjacent elastomeric grade crossing panels that have recesses defined in their lower surfaces that receive the projections. Bores extending through the panels coaxially with the recesses permit bolts to be installed through the panels into threaded engagement with the projections. Since adjacent panels are attached to a common plate, they become interconnected so that the weight of an entire crossing element will resist movement of the panels. In a typical application there are three crossing elements; a gauge element between the rails, and a field crossing element between each rail and the adjacent roadway. Typically, the gauge panels only extend half-way between the rails so that each gauge plate is coupled to the inner corner of four adjacent gauge panels.

Abstract: A paving block for covering the ground, floor and like surfaces. The paving block is generally planar with a vertical dimension. The upper and lower planar surfaces and the vertical sides define a pentagon. the pentagon has three longer sides and two shorter sides. Two of the longer sides are equal. The third longer side is at least as long as the two equal longer sides. The two equal longer sides are joined at one end at a 90.degree. internal angle. Each is joined at its opposite end to one of the shorter sides at a 90.degree. internal angle and each shorter side is then joined at a 135.degree. internal angle to the third longer side. The third longer side opposes the right angle between the two equal longer sides and is bisected by a line bisecting the 90.degree. angle between the two equal longer sides.

Abstract: A portable track device for a wheelchair includes at least two track sections which can be coupled removably to each other, and each track section has a bottom channel between a right sidewall and a left sidewall, with a reinforcement rod in each sidewall and with transverse supports located in the bottom channel. Each track section is equal to, or greater than, the length of the wheelchair. The occupant of the wheelchair can travel safely across difficult terrain, such as a sandy beach.

Abstract: A paving block (10) has substantially parallel top and bottom surfaces, is based upon hexagonal geometry and has a central portion (10a) which is a substantially equilateral triangle and three portions (10b) (herein called apex portions) Each apex portion is located in the region which would otherwise be the location of a respective apex of the triangle. Each apex portion has a first pair of walls (17) each of which in part defines a boundary of one of three recesses in the block and a third wall (17c) which defines an outer boundary of the respective apex portion. The third wall is shaped to secure an interfit between a recess of one block and an apex portion of an adjacent similar block, the interfit being incomplete and arranged to define one of a plurality of water run-away holes (20) in an array of laid blocks.

Abstract: A surface covering slab element with a unique shape which has a combination of straight edges and complementary concave and convex edges. Numerous slab elements of this shape can be assembled in a variety of different ways for generating circular, straight and curved patterns with interfacing edges for connecting curved patterns to straight patterns.

Abstract: An interlocking grid matrix system is adapted for placement over terrain for use as a revetment. The grid matrix system includes a plurality of substantially identical revetment blocks which are interconnected to allow for omnidirectional movements relative to each other. Each revetment block includes a precast grid body having a first major surface, a second major surface, and an edge extending between the major surfaces to define a periphery for the grid body. The grid body further includes a plurality of spaced ears which are joined to and extend from the edge and a plurality of locking channels disposed inwardly of the edge between the ears. Each channel opens to each major surface and the edge and is specifically configured to releasably interlock with an ear of an adjacent grid body such that movement in any direction is permitted between adjacent revetment blocks while maintaining an interlocking relationship therebetween.

Abstract: A molded plastic landscape edging module is adapted to be joined with other modules to form a landscape border. The landscape edging module consists of an elongated, hollow body having two opposed ends. A female connector is formed in one end of the hollow body. A male connector is formed in an opposing end for interlocking with the female connector in another module to join the modules in end-to-end relationship. A pair of longitudinal stabilizing flanges extending outwardly from the sides of the hollow body and extend generally parallel to the ground. The stabilizing flanges are covered by soil when the module is inserted into the ground to stabilize the module.

Abstract: A vinyl walkway paver, particularly the one used as a paving stone with grass contained therein. The paver can be integrally formed to have a surface with a plurality of ridged bodies which are different in sizes. The center of the paver is a recessed portion, the four sides of the recessed portion form a hollow frame, the corners joining the diagonals of the frame are provided with corner holes and corner blocks. By such configuration, a plurality of pavers can be laid on the walkway, the central recessed portion thereof can be filled up with soil for planting grass. Moreover, the interior wall of the hollow frame can be provided with a plurality of ribs to form a suitable rough surface for strengthening the structure of the paver. Expansible materials such as polystyrene can also be filled inside the frame to give a better bonding structure.

Abstract: A honeycomb grass planting unit includes a hexagonal body with six peripheral walls extending vertically and including a plurality of soilpots and a central fence therein. The soilpots are interconnected by plates to reinforce the structure. Holes are formed in the soilpots and the fence through which hoses pass. Two receiving sockets are disposed on diagonal apexes of the hexagonal body and are releasably engaged with four snapping fasteners disposed on the remaining apexes of another hexagonal body to provide a releasable interconnection between two honeycomb grassplanting units.

Abstract: Glazed masonry building unit is provided for constructing a stanchion or turning a corner. The front face of each such masonry building unit is glazed with a resinous composition and is intended to be exposed. the front face comprises a planar portion, a first angled segment that intersects the planar portion at one end thereof to thereby form an obtuse angle, and a second angled segment that intersects the planar portion at the other end thereof to thereby form an obtuse angle. Also provided is a stanchion constructed of a plurality of the glazed masonry building units. Moreover, there is provided a mold for producing the glazed masonry building units.

Abstract: A cover unit 12 adapted to interlock with other such units having a top surface 14 capable of supporting persons. The unit 12 is formed of semi-opaque plastics material thereby providing for a required reduced amount of light to reach any plants located beneath the unit 12. A grid is provided by a plurality of recesses 18, 20 on the surface 14, the recesses 18, 20 accepting liquids thereby permitting evaporation and run-off of the liquids from the unit 12. A framework of ribs 22 is provided on the underside of each unit 12. Locating means may be provided on the ribs 22 in the form of spikes 24 or alternatively feet 224. The locating means are shaped to engage the ground beneath the unit 12 substantially without causing damage thereto. A plurality of ports 28 extend through the unit 12 enabling plants beneath the unit 12 to breathe. The ports 28 and recesses 18, 20 are of a size to be bridged by footwear.

Abstract: The side surfaces of compound stones are provided with relatively flat elements which interlock with little play when said stones are laid out, while adjoining side surfaces of neighboring stones are in contact along two lines only. A compromise between a sufficient mutual securement of the stones and a certain mutual mobility thereof is thus obtained. In particular, a certain tilting of neighboring stones with respect to each other is possible, whereby it is possible to produce pavements in uneven places.

Abstract: An angular paving stone (2) for paving areas, comprising two outer sides (16), two inner sides (18) and two face sides (20). At the five outer corners (4) of the angular paving stone (2) there are provided quarter recesses (22). At the center of the outer sides (16) of the angular paving stone (2) there are provided half recesses (24). At the inner corner (6) of the angular paving stone (2) there is provided a three-quarter recess (26). The partial recesses (22, 24, 26) supplement each other in the paved area so as to form full recesses (38) for water discharge.

Abstract: A flooring system having a base member having a top side, an underside, and four circumferentially spaced outer edges, a tongue connector secured to one outer edge by an interlocking rib and groove, a groove connector secured to another outer edge by an interlocking rib and groove, the tongue connector having forwardly converging compressible sidewalls terminating in rear transverse locking surfaces, the groove connector having an enlarged inner opening and a smaller outer opening, the tongue sidewalls in a compressed position being smaller than said groove outer opening to pass through the outer opening but elastically expandable to be larger than said outer opening to lock a tongue in a groove.

Abstract: A paving stone is provided that can be laid in a plurality of open patterns, each presenting a different amount of drainage area, while retaining an interlocking relationship between adjacent stones of the pattern. In the preferred embodiment, the stone can also be laid in a closed pattern, with no drainage areas provided other than the drainage at the boundaries of the stones. Each side surface of the stone has an odd number of faces, arranged in a stair-step shape. Preferably, each of the side surfaces is symmetrical about the center face, and all sides, or at least opposite sides, are identical.

Abstract: A paving block is made up, as seen in plan, of two connected portions (10, 12) one portion (10) comprising four connected substantially identical quadrants (14-17) and the other portion (12) having an inside-out pillow shape defined substantially by four arcuate surfaces. The curvature of each surface is substantially the same as that of the curved boundary of any one of the quadrants (14-17). Such a block may have various proportions, and may be made to various dimensions. However it is preferred for the blocks to be of such a size and weight that one can readily be held in one hand. This simplifies and makes less expensive the process of laying the blocks. Such blocks when laid have improved structural stability.

Abstract: A unique shaped paving block having a top face, bottom face and 18 flat sides that permits its ready placement by being rotated 60 degrees or less to orient with blocks already in position. The six groups of three exterior and interior sides or faces with an intermediate joining side face provides lock points so that the block is especially usable in high loading areas such as industrial applications and applications at airports.

Abstract: A mat for stabilizing particulate materials includes a planar quadrilateral grid formed by a plurality of intersecting struts. A reinforcement zone strengthens each of the strut intersections. Upstanding cylindrical tubular members are disposed on the grid in a rectangular array such that the central longitudinal axis of each of the tubular members extends through a strut intersection. Longitudinal ribs are formed on an interior cylindrical sidewall of each of the tubular members and are disposed such that each of the ribs perpendicularly intersects a strut adjacent a bottom end of the tubular member. Sockets are spaced uniformly along two adjacent sides of the mat, with each socket secured between two of the tubular members by a pair of struts. Pins are spaced along the other two adjacent sides of the mat, opposite the sockets, with each pin also secured between two of the tubular members by a pair of struts.

Abstract: An interlocking paving stone which has in certain embodiments a twelve-sided main section and an eight-sided tail section, and in certain other embodiments, has a twenty-sided main section and a sixteen-sided tail section, which main and tail sections are integral with each other, coplanar, and symmetrical about a longitudinal plane perpendicular to the paving stone which bisects it into two equal longitudinally extending sections. The relationship of the lengths of the sides to each other and angles they define are such that a large number of different interlocking patterns are possible which exhibit a high degree of interlock along both opposite edges and both opposite ends of the stones.

Abstract: Two forms of paving block are disclosed each having a hexagonal body portion capable of being divided along a central score line into two mirror image portions and one of the forms of block further containing a square stem portion also separable from its associated body portion along a further score line. A ground covering structure is formed by laying the blocks laterally side by side to form a substantially continuous paving employing both forms of blocks and selectively breaking the hexagonal portion of such blocks and fitting the severed mirror image portions into voids whereby the perimeter of the structure can be defined by straight lines without further breaking or cutting of any of the block forms.

Abstract: Shaped slabs (10) made of concrete for forming groundcoverings have spacers (15 to 20) on their edges with which the shaped slabs are braced against one another when the groundcovering is completed. This bracing of the shaped slabs (10) on their spacers (15 to 20) determines the permissible traffic weights such a groundcovering may carry. This means that different shaped slabs have to be provided for groundcoverings which are suitable for heavier traffic weights. The invention is concerned with creating a universal shaped slab (10) which can be used for different traffic weights and therefore suggests shaped slabs (10) the spacers (15 to 20) of which being arranged on the side faces (11 to 14) of said shaped slabs (10) such that depending on the relative positioning of the side faces (11 to 14) when laying the shaped slabs (10), said spacers (15 to 20) are either interlocking or abutting. This way, wide or narrow joints can alternatively be formed between adjacent shaped slabs (10).

Abstract: A composite structure finding principal utility in the formation of walls, floors, patios and the like, for example. The structure is made up of a coplanar assembly of slab-like flat-faced elements provided with knobs and sockets that are congruent with each other as well as being congruent throughout the total structure so as to provide positive interlocks among the elements and thus eliminating the need for adhesive and like binders. The elements may be of molded concrete and relatively light weight so as to facilitate handling on the job by the ordinary artisan in the building of a patio, for example, in the elements are coplanar on a bed of sand, etc. The elements are furnished in several groups in which each group contains several identical elements. In addition to the knob-socket feature, the elements have perimetrical outlines or configurations such that side-by-side elements abuttingly match each other as to contour.

Abstract: A paving block assembly and first and second paving blocks therefor. The first and second paving blocks are combined to form a continuous paving surface. Spacers are provided on the blocks for assuring, among other things, correct positioning of the blocks in a continuous paving surface. The paving blocks have concave and convex curved side surfaces, which increase the durability of the paving blocks. The paving blocks in the paving block assembly form an arch shaped pattern, which increases the stability of the paving block assembly.

Abstract: A paving stone that can be laid in one or more open patterns, permitting water to drain through areas in the formed ground cover, is provided. The stone has six interlocking multifaced side surfaces, three on a concave part of the stone and three on a convex part of the stone, that interlock with complimentary side surfaces of adjacent stones, and has eight corner side surfaces that bound and define the shape of drainage areas. Each of the drainage areas is surrounded by identical interlocking stones. In the preferred embodiment, the multifaced surfaces of each of the parts are identical so that the stones can be laid interchangeably at any place in a runner bond or herringbone pattern. The faces of the multifaced side surfaces of the stones are preferably planar and form V-shaped interlocking surfaces.

Abstract: A roadway/platform mat construction is provided for disposition over soft ground. The mat construction includes a rectangular, panel-like mat structure including opposite transverse end margins and opposite side longitudinal margins. The mat construction defines a first rectangular surface and a second rectangular surface facing opposite and paralleling the first surface and including elongated transverse log structures carried by the opposite ends of the mat structure and projecting outwardly of the second surface thereof. The transverse logs are of a width measured longitudinally of the mat construction equal to substantially one-quarter the length of the mat construction and the spacing between opposite end logs of each mat construction measured longitudinally thereof is equal to substantially one-half the length of the mat construction.

Abstract: A slab element for covering a ground surface and the like, the linear, curvilinear, and circular-design surfaces produced by the slab elements, and a method of forming the design surfaces. The slab element comprises a rectangular slab element having a convex and a concave end adapted to interlock and be rotatable, with grout material therebetween, and the peripheral sides of the slab element entirely curvilinear.

Abstract: The individual structural member of the invention includes a pair of parallel panels which are spaced from each other to define a cavity therebetween. The panels are staggered in the longitudinal direction so that an end section of one panel extends beyond an end of the other panel and vice versa to form a front extension section and a rear extension section of the structural member. The non-extension end edge of each panel is connected to the opposing panel by flat walls. Each extension section is provided with a flange. The front section flange of one structural member is adapted to interlock with the rear section flange of another structural member so that the structural members can be assembled in end to end fashion with the panels of one structural member being coplanar with the panels of adjoining structural members to form a double wall of, for example, a container .

Abstract: A revetment unit for protecting shoreline or waterway embankments from eron comprising a generally L-shaped web having first and second arm portions converging at an apex and forming a 90.degree. right angle. Each of the first and second arm portions terminate at end portions. Identical cylinder members are associated with the web and extend above and below the plane of the web. The cylinder members have a height substantially less than their width and a single cylinder member is positioned at each of the end portions and at the apex. The web has a width slightly less than the diameter of the cylinder members yet greater than the radius of the cylinder members. The end portion cylinders are equally spaced from the apex cylinder a distance between about 0.10 to about 0.25 of the diameter of the cylinders.

Abstract: A integrally molded paving stone or slab element of ceramic material, and a ground cover made up of repeatable patterns of such elements wherein the slab elements include a hexagonal section having two 90.degree. and four 135.degree. angles and lateral and longitudinal sides and a square section with a side adjoining a side of the hexagon which is adjacent one of the 90.degree. angles. The lateral sides of the hexagon adjacent the 90.degree. angles and the sides of the square are from 3.5" to 5", approximately and the longitudinal sides of the hexagon section are such that there are approximately 9" to 11" from one 90.degree. angle to the other. Such a paving stone provides superior support for standard dual wheel truck loads when assembled in a ground cover.

Abstract: A kit of cobble stone elements of varied shapes which when fitted together into a close-fitting fan-shaped composite of which a plurality of the fan shaped composites symbolic of a fish scale form a close-fitting integrated repetitive design of unique and novel appearance.

Abstract: The interconnecting paving stones are provided on at least two opposing sides with outwardly tapering teeth. On one side of said stones, the front sides of said teeth are provided with indentation keys, and on the other side, with indentation grooves. Moreover, the flanks of one row of teeth comprise spacing bosses. An interconnecting paving stone can have the configuration of a rectangular stone and can comprise three teeth on each of its longitudinal sides and either a projection or a recess on the narrow sides.The interconnecting paving stones can be used either for the construction of bicycle lanes with increased smoothness, in which case said teeth engage with each other, or as interconnecting lawn stones, where respective teeth adjoin and interlock by means of said indentation keys and grooves.

Abstract: Disclosed is a structure of square floor tile, which is made of glass fiber mixed with heat setting resin, calcium carbonate and hardener through casting process, and comprises two pair of parallel ribs on the bottom and vertically intersected with each other. The parallel ribs have each two notches thereon, a dovetail mortise at one end and a dovetail tenon at an opposite end. By means of the engagement of the dovetail mortises of one floor tile with the dovetail tenons of another floor tile, floor tiles are automatically aligned with one another after they are connected together longitudinally and transversely.

Abstract: An interlocking paving stone which has a twelve-sided main section and an eight-sided tail section which are integral with each other, coplanar, and symmetrical about a longitudinal plane perpendicular to the paving stone which bisects it into two equal longitudinally extending sections. The relationship of the lengths of the sides to each other and angles they define are such that a large number of different interlocking patterns are possible which exhibit a high degree of interlock along both opposite edges and both opposite ends of the stones.

Abstract: Removable sidewalk and a method of installation involves preformed sidewalk slabs provided with interlocking means at two opposite ends. The slabs include attachment means for lifting the slabs into place. The slabs may be installed over utility services to form a sidewalk and removed and replaced as necessary to provide access to the underground utilities.

Abstract: Construction elements each consist of a central section and two external sections, with the central section having, in addition to flat top and bottom surfaces, two parallel side walls and four, shorter side walls arranged at angles relative to the longer side walls. Pairs of the angled side walls would intersect at right angles were they to extend to the two external sections. The two external sections are cylindrical in shape and of a height less than the height of the central section, with the remaining portion of the central section having a cylindrical wall that may be thought of as a continuation of the external section. By providing the external sections with a height less than the central section, it is possible to line up the elements adjacent to each other with the external sections of adjacent construction elements overlapping in order to form a temporary curbstone or traffic control structure.