Abstract: A reinforced retaining wall is provided comprised of precast, concrete block facing elements connected by suitable connectors to reinforcing members which extend from the facing elements into the adjacent reinforced soil to form a mechanically stabilized earthen wall construction. The connectors which affix the reinforcing members at their connecting ends to the facing elements comprise concrete poured into a part or all of certain of the void spaces within selective facing blocks, which concrete may or may not be reinforced and which concrete, when dry and cured, envelops and secures the connecting ends of the reinforcement members to their corresponding blocks and forms anchors thereat.

Abstract: A modular earth retaining wall system comprising a plurality of similarly configured wall blocks that have lock channels and lock flanges that provide a locking mechanism for resisting leaning or toppling of the blocks. A positive retaining mechanism is also provided for attaching reinforcement fabrics to the retaining wall in between mating courses of wall blocks. This mechanism secures the reinforcement fabrics in place and permits the fabrics to extend along the entire contact area between adjacent stacked wall blocks to avoid an aggregate leaning effect. The retaining mechanism includes a retaining bar that is placed on top of the reinforcement fabric within the lock channel. The retaining bar holds the fabric against a wall of the lock channel in response to tensile loads applied to the fabric to prevent it from being pulled out of the retaining wall.

Abstract: A retaining wall system and method for stabilizing earthen walls. The system comprises a wall panels assembled together to form a reinforcing wall assembly and anchor mesh connected to the wall panels and buried within the earthen wall. The wall panels engage the face of the earthen wall, and the anchor mesh inhibits lateral movement of the reinforcing wall assembly. The panels are connected to the anchor mesh by locking pins that extend through loop portions of the anchor mesh and engage a front face of the wall panels. Anchor bars are connected to the loop portions of the anchor mesh; these anchor bars engage a back face of the wall panels to control and limit the movement of the wall panels relative to the anchor mesh as earth is back-filled against the wall panels. When the wall panels are concrete, a void network is formed in the panels to receive the anchor mesh loop portions and the locking pins. Pin windows may be formed in concrete wall panels to facilitate insertion of the locking pins.

Abstract: A modular block wall includes dry cast, unreinforced modular wall blocks with anchor type, or frictional type or composite type soil stabilizing elements recessed therein and attached thereto by vertical rods which also connect the blocks together. The soil stabilizing elements are positioned in counterbores or slots in the blocks and project into the compacted soil behind the courses of modular wall blocks. Alternative stabilizing element designs may be used with the modular wall blocks and other types of facing elements in a mechanically stabilized earth structure.

Abstract: Bonded composite open mesh structural textiles are formed of woven textile. The textile is formed from at least two, and preferably three, components. The first component, or load bearing member, is a high tenacity, high modulus, low elongation mono- or multifilament yarn. The second component is a polymer in yarn or other form which will encapsulate and bond yarns at the junctions to strengthen the junctions. The third component is an optional effect or bulking yarn. In the woven textile, a plurality of warp yarns are woven with a plurality of weft (fill) yarns. The weave preferably includes a half-cross or full-cross leno weave. At least a portion of the warp and weft yarns are first component load bearing yarns. The polymer component is used as required for the bonding properties necessary for the finished product, and especially to provide improved junction or joint strength.

Abstract: A modular block wall includes dry cast, unreinforced modular wall blocks with anchor type, or frictional type or composite type soil stabilizing elements recessed therein and attached thereto by vertical rods which also connect the blocks together. The soil stabilizing elements are positioned in counterbores or slots in the blocks and project into the compacted soil behind the courses of modular wall blocks. Alternative stabilizing element designs may be used with the modular wall blocks and other types of facing elements in a mechanically stabilized earth structure.

Abstract: A concrete masonry unit especially suited for use in soil reinforced retaining walls is provided. The reinforced retaining wall is comprised of precast, concrete block masonry unit facing elements connected by suitable connectors to reinforcing members which extend from the facing elements into the adjacent reinforced soil to form a mechanically stabilized earthen wall construction. The connectors which affix the reinforcing members at their connecting ends to the facing elements comprise concrete poured into a part or all of certain of the void spaces within selective facing blocks, which concrete may or may not be reinforced and which concrete, when dry and cured, envelops and secures the connecting ends of the reinforcement members to their corresponding blocks and forms anchors thereat. The novel masonry unit disclosed herein effectively provides maximum facing area per unit volume (weight) of block, always exceeding 4.0 m.sup.2 /m.sup.

Abstract: A retaining wall construction includes a lower mechanically stabilized earth bulk form with tensile members projecting from the front face of the bulk forms and connected to precast wall panels that are spaced from the front face of the bulk form. The space between the front face of the bulk form and the panels is filled with concrete. Positioned on top of the reinforced concrete and the first bulk form, as well as along the sides thereof, are additional bulk forms which include tensile members connected directly to the front facing panels.

Abstract: A retaining wall system to align panels into a plurality of horizontally adjacent vertical assemblies of stacked cells to retain soil placed between the cells.

Abstract: Adjustable connections are provided to enable facing to be secured to anchor elements embedded in an earthen formation, without requiring precise alignment of the anchor elements with connectors on the facing. In one embodiment specially configured bars engage and span the connectors on the facing for rotation relative to the connectors and slotted plates are carried by the bars for connection to the anchor elements. In another embodiment a channel structure is secured to and extends across the facing and a plate assembly having a slot therein for receipt of the anchor elements is slidably received within the channel structure. The anchor elements may comprise bolts secured to a cross-member extending behind soil reinforcing mats embedded within the earthen formation being retained.

Abstract: A retaining wall for reinforced infill material of the type comprising superimposed courses of modular blocks, each block having a front face, a rear face, parallel upper and lower faces, and opposed sidewalls which extend between the upper and lower faces. Reinforcement material extends back from the wall into the infill material with an end portion of the reinforcement material interposed between two superimposed coursed of the wall and anchored to the wall by an anchor element which is retained in a retaining cavity between contiguous upper and lower faces of blocks in the superimposed courses. The anchor element has a spine which is of wedge-shaped cross-section for at least part of its length and has a plurality of spaced-apart projections extending from one side there of and engaging through apertures in the reinforcement material.

Abstract: A wall construction block for the construction of earth retaining walls includes a pair of spaced-part transverse pin receiving channels in the end walls of the block and disposed parallel to one another along respective longitudinal axis of the block which are parallel with a front face of the block. The pin receiving channels extend transverse from a top surface to a bottom surface of the block and are of substantially uniform cross-section throughout. Arresting pin elements are received in sliding fit within some of the receiving channels and are retained captive therein. Elongated parallel grooves are provided on a top surface of the block and extend across the end walls and parallel to the front wall. One of the groove is aligned between a first set of the pin receiving channels and the other of the parallel grooves is offset a predetermined distance between the other set of pin receiving channels.

Abstract: A soil reinforced structure comprised of superimposed courses of concrete blocks, at least some of which have rearward portions separable therefrom. Longitudinally extending soil reinforcing members extend around the separable rearward portions and are captured between the courses of blocks thereabove and therebelow. In one embodiment the blocks have bifurcated forward portions about which a cast in place concrete face may be formed. Another embodiment disposes courses of the blocks in opposed spaced relationship and extends the soil reinforcing members between the blocks to form a earthen fortress.

Abstract: A flexible plastic soil reinforcing element is secured to the retaining face for an earthen formation by folding an end portion of the element upon itself and then securing the end portion to the face. An anchor extends rearwardly from the face and a retaining rod is engaged with the end portion of the soil reinforcing element and the anchor to secure the reinforcing element against separation from the anchor. In one embodiment, the end portion of the reinforcing element is folded upon itself multiple times to increase the shear strength of the element to either side of the anchor. In another the end portion of the reinforcing element is folded back over the reinforcing element for embedment in the earthen formation.

Abstract: A retained earth structure includes an upright soil retaining wall of interlocking facing panels and a plurality of horizontal elongated wire mesh reinforcement panels extending outwardly from the back surface of the modules into the backfill material. The wire mesh panels are connected in tiers to the retaining wall while embedded in the backfill material soil behind the wall by use of a three-way adjustable, turnbuckle-type connector assembly. The three-way adjustable turnbuckle-type connector assembly ensures verticality of the finished precast wall panels.

Abstract: An earthen work bulk form construction has a wire mesh facing and granular compactable fill with stabilizing members projecting horizontally into the fill from the front facing. The front facing is comprised of modular shaped panels which form a mosaic pattern that enables construction of the wall with non-adjacent panels serving to facilitate and support adjacent panels. Connection of the stabilizing members to the front panels is effected through a quick engagement and locking handle bar connector.

Abstract: An earthen work bulk form construction has a wire mesh facing and granular compactable fill with stabilizing members projecting horizontally into the fill from the front facing. The front facing is comprised of modular shaped panels which form a mosaic pattern that enables construction of the wall with non-adjacent panels serving to facilitate and support adjacent panels. Connection of the stabilizing members to the front panels is effected through a quick engagement and locking handle bar connector. A handle bar connector is used for connecting a cast in place front wall to the front panels and bulk form.

Abstract: Precast modular concrete wall blocks are assembled to form a retaining wall in front of a limited depth cut wall face. Arched confinement cells are formed behind the courses of blocks by sections of vertically oriented sheet material for reception and retention of a particulate fill material. Each wall block is provided with a channel or slot for attaching opposed edge portions of the cell-forming sheets of material to the rear surfaces by an interference fit or by comb-like grid connecting devices to define generally semi-circular confinement cells to reinforce the retaining wall. The fill material uniformly flexes the cell-forming sheet material and also surrounds the space between the confinement cells and cut wall face.

Abstract: A method for and inserting a ground anchor into the ground, comprising the step of screwing an elongated anchor body into the ground by means of an extension tube that is to be connected to the proximal end of the anchor body. The distal end of a tension line is connected to the anchor body above the screw blade turns. A pipe sleeve is slid onto the extension tube, while guiding the tension line via an eyelet at the pipe sleeve adjacent to the distal end of the pipe sleeve, from the anchor body along the pipe sleeve. The anchor body is then screwed downwardly by turning the extension tube and the pipe sleeve jointly to a predetermined depth. Finally, the pipe sleeve together with the line extending there along are rotated around the stationary anchor body/extension tube assembly.

Abstract: A retaining wall secured to a portion of earth, comprising a plurality of blocks stacked in longitudinally extending, vertically spaced tiers to define a retaining wall, each of the blocks defining a laterally oriented passageway extending between a pair of opposing sides thereof and having an exterior face orientated outwardly of the portion of the earth, the passageways being substantially aligned in each tier to define a channel within the tier of the retaining wall at least one tieback rod for being embedded at one end in a portion of earth to be covered by the retaining wall and having a protruding end extending therefrom towards the retaining wall at least one elongate member disposed within a portion of one of the channels in the tiers of blocks, the elongate member defining a slot through which the protruding end of the tieback rod extends and a mechanism for connecting the tieback rod to the elongate member to secure the retaining wall to the portion of earth.

Abstract: A strip for use in a stabilized earth structure has a tensile portion in the form of an elongate core which supports lateral friction wings and optional ribs. The elongate core may be steel or a polymer material and the wings are fabricated from a plastic material. Alternatively, the strip may be made from a single material (e.g., plastic) with a thickened region defining the core and thinner regions providing the friction wings.

Abstract: For coupling anchor bars (2) of injection anchors, the anchor bars are screwed with their outer threads (4) into a coupling sleeve (1) provided with a corresponding inner thread (5). One of the two anchor bars (2) screwed into the coupling sleeve (1) has a chamfered surface (8) formed by an end chamfer and lies on a break (6) of the inner thread (5) of the coupling sleeve (1). The second anchor bar (2) is screwed into the coupling sleeve (1) until its end face (9) lies completely on the end face (9) of the other anchor bar (2). This ensures an advantageous transmission of forces during drilling and prevents the coupling sleeve (1) from turning during drilling.

Abstract: A retaining wall block and wall construction are disclosed. The retaining wall block is characterized in that it includes a removable flange having pin apertures which pass through the flange and into the body of the block. Such blocks allow the construction of walls having flange connections between adjacent courses of blocks or, when the flange is removed, pin connections between adjacent courses of blocks. The latter connection system is particularly well-suited for constructing walls that require soil reinforcement systems such as geogrids.

Abstract: A retaining wall assembly having a plurality of face plates, which interlock with tie-backs. The face blocks in one embodiment have a substantially cross-shaped front face and recesses along top, bottom, left and right-hand sides, which interlock with tie-back flanges. Each tie-back, through its interlocking flange, interlocks with four adjacent face plates. The tie-backs have anchors which provide stability and anti torsion, and comprise elongated rods joined to a key block at a forward end, which is further provided with a stiffener plate. The back feet, which are preferably rebars, are welded to the key block and extend rearwardly therefrom. A plurality of anchor plates are arranged at spaced (preferably equi-spaced) intervals therealong and are joined thereto preferably by welding. Tie-backs of a plurality of lengths N.times.K are provided where N is a real integer and K is a given length. In addition, tie-back extensions may be joined to a tie-back or another tie-back extension in the field.

Abstract: A modular plastic wall block to be used for forming a retaining wall including a plurality of vertically superimposed courses, each course including a plurality of laterally juxtaposed wall blocks. Each wall block is formed of a wall block frame and an easily replaceable facing panel interconnected by a tongue and groove connection. By rotating the facing panel by 90.degree., it can be used to overly and conceal at least a portion of the top of an uppermost course of wall blocks in the retaining wall. The wall blocks include elements for side-to-side connection enabling juxtaposed wall blocks in each course to be laterally aligned to form a straight portion of a face of a retaining wall, or to be angularly positioned to form concave or convex portions of the face of the retaining wall without the formation of gaps between adjacent wall blocks.

Abstract: This invention relates to a geogrid structure which is comprised of two or more layers of rigidly bonded flexible mesh structures. The mesh openings of each layer, without superimposing, overlay mesh openings of other layers, resulting in a geogrid structure which consists of small and large sized mesh openings. The smaller sized mesh openings are designed to reduce vertical migration of the smaller aggregate particles into the subgrade and to reduce pumping of the subgrade material into the aggregate layer. The rigid bonding of multiple layers of mesh structure provides a mechanism for transmission of tensile stress which is less dependent upon interlocking of aggregate particles. Furthermore, by bonding multiple layers of mesh structure, the number of tensile elements per unit area is increased, and as a result, the interaction of the geogrid with the fill material is enhanced.

Abstract: A facing element 20 is formed from cast concrete and provided with a connecting member 23 located in a recess 22. The element is particularly appropriate for use in combination with flexible reinforcing strips. The connecting member may be a simple molded cylinder of plastics or alternatively it may be partly or wholly formed of concrete and be cast integrally with the rest of the facing element. The casting may be facilitated by means of a plastic shell which is set into the concrete and defines the connecting member and recess. To strengthen the connecting member, a reinforcing bar passes through its center.

Abstract: A facing panel (1) is provided for assembly with like facing panels to form a facing of a stabilized earth structure. The facing panel has two opposed side edges (2) for arrangement edge-to-edge with the side edges of laterally adjacent facing panels, each side edge having a front portion (5) which is straight over substantially the full height of the facing panel, and a rear portion comprising a lateral projection (8) over part of its length and an abutment (6, 7) over another part of its length, the lateral projection being provided for engagement behind a respective abutment on the side edge of a laterally adjacent facing panel to restrain forward movement of the facing panel, and the abutment being provided for engagement in front of a respective lateral projection of said laterally adjacent facing panel or of another laterally adjacent facing panel to restrain rearward movement of the facing panel.

Abstract: The invention comprises a set of two composite masonry blocks, a wall block and an anchor block to construct retaining walls. The wall block is generally trapezoidal in shape and has: a decorative front face opposite and generally parallel to a rear face which defines a key way. The wall block has a top surface which is opposite and generally parallel to a bottom surface. The wall block has side faces which are not parallel so that the width of the rear face is shorter than the width of the front face. An alignment and locking ledge projects downward from the bottom surface and extends across the rear face. The anchor block comprises a first end plate which is opposite and generally parallel to a second end plate. Two parallel side plates extend between and are perpendicular to the first and second end plates. The side plates and the first and second end plates define a central passage.

Abstract: A precast concrete block having a first single thickness generally planar face section and a second single thickness generally planar backing section integrally formed with and extending from the first section to form a structure of a T-shaped configuration. A groove extends across and opens through an upper edge of the second planar section for the receipt of a rebar. The blocks are assembled into stacked side-by-side relationship and a panel is formed by casting concrete against the side of the generally planar face sections from which the backing sections extend. Rebar extends across and through the grooves of at least certain of the blocks to maintain the blocks in aligned side-by-side relationship and reinforce the concrete cast against the blocks. The panels are used in the construction of retaining walls for earthen formations and may be precast or formed in place at the situs of the formations.

Abstract: A modular block wall includes dry cast, unreinforced modular wall blocks with anchor type, or frictional type or composite type soil stabilizing elements recessed therein and attached thereto by vertical rods which also connect the blocks together. The soil stabilizing elements are positioned in counterbores or slots in the blocks and project into the compacted soil behind the courses of modular wall blocks. Alternative stabilizing element designs may be used with the modular wall blocks and other types of facing elements in a mechanically stabilized earth structure.

Abstract: The present invention provides a retaining wall block adapted to receive and retain a geogrid reintorcing material. In one aspect the receiving and retaining structure comprises one or more projections (13,33) provided on a first face of the block and an aperture or recess (14,34) provided on the opposite face of the block. In a further aspect of the inventions the receiving and retaining structure comprises a transverse groove (53) formed in an upper surface of the block. In a yet further aspect, the receiving and retaining structure comprises a transverse slot provided in the rear wall of a block, the slot comprising a groove (62,72) terminating in the body of the block in a cavity (63,73,83) of greater lateral dimension than the groove.

Abstract: A retaining wall having a height of greater than ten feet which includes a lower section of inextensible reinforcements and an upper section of extensible reinforcements. By the use of inextensible reinforcements in place of extensible reinforcements in a lower portion of a wall having a height greater than ten feet, the lower portion of the wall will tend to distribute the stresses of soil compaction and require less quality control/assurance during construction. Further, by the use of extensible reinforcements in the upper section of a retaining having a height greater than ten feet, the extensible reinforcements will maintain the retaining wall in place and have significantly improved corrosion resistance over inextensible metal reinforcements.

Abstract: An earth structure includes a plurality of elongated stabilizing elements in an earth mass behind a facing made up of facing panels. A plurality of connectors behind the facing connects the facing to the stabilizing elements. Each connector has a rear attachment portion attached to a respective stabilizing element, and each connector also has at least two spaced apart front attachment portions attached to a facing panel. The earth mass includes a first region of soil suitable for plant growth which also defines the region in which the connectors are located. A second region of structural back fill is provided which includes the stabilizing elements.

Abstract: An earth retaining wall having at least a pair of tiers of side-by-side blocks which define a receiving channel for a connector bar with spaced-apart keys that engage apertures in a lattice-like grid extending laterally from the tiers, the grid being covered by backfill for interlocking the backfill with the retaining wall, the keys distributing the load of the backfill evenly across the wall.

Abstract: A retaining wall unit and retaining wall made from the retaining wall units wherein the retaining wall unit includes a support structure such as a meshlike enclosure for holding an anchoring medium such as rocks therein, a slab having a stone face and a rearward face for attachment to the support structure and an optional securing device such as a snap-lock device which enables the slab to be releasably secured to the support structure.

Abstract: A hollow in the ground is filled in by positioning a base facing unit (10) adjacent a side of the hollow (29), positioning a plurality of further facing units (1) extending upwardly from the first facing unit (1), filling in the gap between the facing (20) and the side of the hollow (29), and filling in the remainder of the hollow in the ground. The facing (20) has a smooth face to prevent damage to a liner (26) of impervious material that is laid over the facing (20) to prevent transfer of pollutants from the material in the hollow. Adjacent facing units (1) are held in interlocking engagement by tongues (21) which are anchored by tethers (30) to the material in the gap between the facing (20) and the side of the hollow (29).

Abstract: A soil reinforced retaining wall includes a soil reinforcing mat connected to a face panel. The face panel is vertically disposed with a back facing the earthen formation and is preformed to include an anchor embedded in the face panel and extending from the back in at least one predetermined location. The soil reinforcing mats are horizontally disposed within the earthen formation in general correspondence with the predetermined location. The mats have an end adjacent the face panel folded to form substantially a right angle portion of the mat including a vertical face and a horizontal face. A right angle member having a vertical face and a horizontal face is disposed in contact with the corresponding vertical face and horizontal face of the right angle portion of the mat. The right angle member is then secured to the anchor such that the right angle portion of the mat is rigidly held therebetween.

Abstract: A wire mat for a retaining wall structure has a unique prong portion extending upwardly from a vertical face. The prong portion has a series of bends in its middle that extend over a lower portion of a similar wire mat located immediately above such that the series of bends interleaves with longitudinal members of the wire mat above. In a preferred embodiment one or more connecting pins are inserted between the prong portion and the longitudinal members of the mat above.

Abstract: A ground anchor assembly comprises a looped cable 3 passing around a saddle 4 with one or more optional recesses 8 in its outer surface 7, all this being held in place by solidified grout or the like in an elongate bore 1. Extension 5 gives good transfer of forces when both cable ends are stressed outwards, and tubes 6 prevent internal cracking of the grout. After a period of use the cable 3 can be removed by pulling one cable end only.More than one such cable 3 can pass round saddle 4, and more than one such assembly can locate in the bore 1.

Abstract: A retaining wall for an earthen formation uses welded wire face mats having upright portions secured to one another and spanning the distance between successive lifts of the wall at the face of the formation. Elongate welded wire soil reinforcing mats with bent-up ends of a height less than the distance between successive lifts are secured to the face mats so as to extend partially over the upright portions and into the earthen formation. The bent-up ends of the soil reinforcing mats are formed with kinks which extend through the upright portions of the face mats. Rods extend through these kinks to secure the upright portions of the face mats against separation from the bent-up ends of the soil reinforcing mats. In a preferred embodiment, the face mats have a width greater than the width of the soil reinforcing mats and the soil reinforcing mats at each lift of the wall are spaced from one another and span adjacent face mats.

Abstract: A retaining wall construction comprises modular facing blocks connected by fasteners to anchoring blocks positioned behind the facing blocks. The facing blocks are arranged in courses which overlap one another. The facing blocks, as well as the anchor blocks, have hollow, vertical throughbores. This enables interconnection of the back wall of the facing block with the anchor block by means of various types of fasteners. The retaining wall construction is especially useful in the construction of low height, gravity type walls.

Abstract: A method of producing an intended breaking point at a predetermined location of a tension member for a soil anchor of a strain-hardened steel or a steel which is not which is not in a thermodynamic equilibrium, for example, a wire or a steel wire strand, to enable removal of the free steel length after use by applying a tensile force which exceeds the working load. The predetermined breaking point is obtained by heating the tension member at a predetermined location in a controlled manner to a temperature at which the state of strain-hardening or the state of being not in a thermodynamic equilibrium is at least partially cancelled, wherein the predetermined breaking point has a breaking load which is equal to or smaller than the breaking load of the untreated tension member, but greater than the yield point of the untreated tension member.

Abstract: Concrete blocks are formed with intersecting grooves in the underside thereof which assume aligned condition when the blocks are assembled into side by side relationship to form panels. Polymer or welded wire grids are received within the aligned grooves to hold the blocks in the panel configuration. The grids are held in elevated seated condition within the grooves during assembly of the blocks into the panel configuration. Stands or wire connectors may be provided for the latter purpose. In the preferred embodiment the blocks are L-shaped and formed with passages extending therethrough and the grooves intersect these passages. Grout or fill may be placed within the passages of the assembled panels. In certain embodiments, the blocks may be disposed in side-by-side relationship and stacked to form retaining walls for earthen formations, with rods received within the grooves of the blocks to hold the blocks in alignment and the grids extending from the blocks to serve as soil reinforcements.

Abstract: Precast concrete wall panels are assembled to form a retaining wall in front of a cut wall face. Arched confinement cells are formed behind the wall panels by sections of vertically oriented sheet material for reception and retention of a particulate fill material. Preferably, flat, precast concrete wall panels provided with vertically oriented tabs of integral geogrid projecting rearwardly from opposite sides of a rear face thereof which are connected to opposite end portions of a length of vertically oriented geogrid by a Bodkin joint. The thus formed confinement cells are generally semi-circular. The fill material initially used fills the confinement cells and then the space around the confinement cells and in front of the cut wall face. The wall panels are vertically staggered and successive courses of confinement cells are filled until reaching a desired height for the retaining wall.

Abstract: A retaining wall system is constructed in several distinct layers. Each layer is formed of a side-by-side arrangement of I-shaped subassemblies with backfill cheers defined between each pair of subassemblies. Each subassembly is constructed of generally planar elongated concrete blocks which interconnect to laterally secure the blocks to one another. Interconnections are provided by dovetail joints in which a tongue is vertically slid into a groove to prevent lateral separation. The dovetail elements extend only partially across the face of each block so that the block defining the groove is not excessively weakened by the groove.

Abstract: The construction block has a projection approximately centered on its top surface. The construction block also has a groove at each of the opposite ends on its bottom surface, each groove being approximately centered about the longitudinal axis. The construction block further has at least one slot defining an end piece, transverse to the longitudinal axis, on the top surface or the bottom surface, located approximately halfway between the center point and one of the opposite ends. The block may be stacked on two identical blocks having their opposite ends facing each other, with the block resting on half of each of the two identical blocks, so that the groove at one of the opposite ends of the block is located above half of the projection of one of the identical blocks and the groove at the other opposite end is located above half of the projection of the other identical block, thus staggering the blocks.

Abstract: A method for underground excavation below an area, without opening the area above the excavation, the method comprising constructing at least a pair of diaphragm walls, the walls being at two opposite sides of the area and extend substantially from the surface area to beneath the lowest level of the excavation. Either prior or after constructing the walls, a plurality of tunnels are bored under the surface area, with the tunnels extending from one diaphragm wall of a pair to another and having a diameter allowing them to accommodate one or more cables. Then, the one or more cables are inserted through the tunnels, and tensioned with their ends anchored to two diaphragm walls of a pair and excavating is performed between said diaphragm walls and beneath the cables.

Abstract: A wall retention system for abutting against and retaining a mass of earth, comprising in combination: (a) a set of flat facing slabs, each facing slab having an outer flat surface and an inner, reinforced surface. The facing slabs are edgewisely interlocked to form a single continuous wall structure. Foundation slabs abut on the ground, and support the lower portions of the facing slabs wherein the facing slabs are supported in generally upright condition. A number of elongated brace bars are provided, integrally carried at their inner ends by the facing slabs reinforced surface and transversely projecting therefrom at vertically spaced intervals. These tension members embeddingly anchor into the mass of earth to be retained. Hence, large horizontal loadings from the mass of earth can be sustained by the wall retention system, without compromising the angularity of the facing slabs relative to ground level.

Abstract: A member (1) for insertion into a borehole (9) in a receiving material (10) has an axially extending generally cylindrical hollow body (2) closed at its leading end (4) and open at its trailing end (5) and into which a mortar mass and anchor member can be inserted. The hollow body (2) has a sieve-like mesh wall. At least one circumferentially extending strip (8) of a compressible elastic open pore material is secured on the outside surface of the hollow body (2) for cleaning the surface of the borehole while the member is inserted into the borehole.