Abstract: A T-joint includes a frame extending along a longitudinal axis. A rung has at least one cavity and at least one cavity wall. The at least one cavity wall is parallel to the longitudinal axis. The rang has at least one fill opening. At least one T-joint part is fixedly connected to the frame. The at least one T-joint part extends into the at least one cavity. The at least one T-joint part is mechanically connected to the rung and is glued to the rung. The at least one T-joint part has at least one glue distribution channel that is substantially parallel to the longitudinal axis. The at least one T-joint part has at least one transverse opening which extends toward the at least one cavity wall such that the at least one fill opening, the at least one glue distribution channel and the at least one transverse opening are in fluid communication.

Abstract: To facilitate the casting of stronger and more precise steel reinforced concrete members and also to facilitate the formation and field joining of such members there is provided a bar splice which comprises a generally cylindrical sleeve open at one end to form an axially elongated chamber to receive a steel reinforcing bar telescoped therein, and provided with internal threads at the other end whereby a threaded bar end may be secured to the other end, and when secured sealing the other end of the chamber. The threads are preferably tapered and the chamber includes inwardly extending axially spaced annular ribs. Lateral ports are provided at each end of the chamber. The wall thickness of the chamber adjacent the threaded end of the sleeve may be increased to improve tensile capabilities. The length of the chamber is most of the splice sleeve since the threaded connection occupies little axial space.

Abstract: A rotor assembly for a multi-lobed trochoidal rotary engine, said assembly including a flat trochoid shape rotor which defines a bore by which the rotor is rotatably mounted on the crankpin of a crankshaft, and a steel hub, secured in the bore so as to project beyond one of the opposite side faces of the rotor, characterized in that the hub is mechanically inter-locked with the rotor in an arrangement which allows for differences in thermal expansion co-efficients of the rotor and hub, while substantially preventing relative rotation between the rotor and hub and substantially preventing radial separation of the rotor and hub.

Abstract: Instead of creating hand railings by joining together sections of rectangular hollow tubing using mitre cuts and welding of the abutting cut ends, a metal knuckle is welded to the straight ends of such tubing. The knuckle has a body with a rectangular cross-section and in profile a circular sector with an included angle less than 180.degree.. Each end of the knuckle is formed as a pyramidal frustum that is adapted to enter the straight end of the tubing. A notch of generally triangular cross-section is created to hold welding bead between an end of the tubing and a respective frustum end of the knuckle. The notch size increases with the thickness of tubing inserted over the frustum end, and filling the notch with welding bead will automatically increase the joint strength as tubing thickness increases.

Abstract: A device for connecting separate material pieces which are disposed in abutting relationship to each other and which includes a thin planar body having side portions adapted to respectively extend into open-ended slots provided on each of the abutting surfaces of the material pieces in which a pocket construction is provided for a stiffening member which is separate and apart from the device body.

Abstract: To improve a joint connection comprising a first part and a second part which are fixed relative to one another by positive connection in a direction of load such that essentially no lumped loads occur, it is proposed that the first part and the second part each have an undercut extending transversely to the direction of load, that in a joining position the undercuts stand facing one another and in spaced relation to one another in the direction of load and thereby form between them a space containing a positive connection element which is introduced in a formable state into and cured in the space and hence lies which surface-to-surface contact on the undercuts, and that the positive connection element and the undercuts exerting a pressure load on it together form the positive connection.

Abstract: A mortar grouting type connector for reinforcing bars having a grouting port and a discharging port disposed adjacent the ends thereof, a plurality of annular ridges provided on its internal surface and a stopper provided approximately at its mid-length portion, wherein a plurality of longitudinal flanges are provided which extend from around the stopper toward one end opening of the connector. The longitudinal flanges are provided to align the reinforcing bars within the connector and prevent the tip of the reinforcing bar inserted into the connector from being displaced.

Abstract: A composite fastener, preferably in the form of a rivet, which comprises a shank having a first head integrally formed on one end thereof, the shank and head formed of a high temperature thermoplastic matrix material selected from the group consisting of a polyether ether ketone resin and a polyamide imide resin, and having continuous reinforcing fibers, such as graphite fibers, axially oriented in substantially parallel relation throughout the shank, the fibers being flared and extending continuously into the head and substantially evenly flared and swaged therein, thereby forming a fastener having high shear and high tensile characteristics.

Abstract: An air bag device for a driver seat is formed of a retainer composed of a main plate portion having an opening for mounting an inflator and mounting pieces extending uprightly from peripheral edges of the main plate portion, an air bag having a rear end connected to the retainer, an inflator mounted on the retainer, and a module cover for covering the air bag, the retainer being made of a synthetic resin, and the rear end of the air bag being secured to the retainer by embedding the rear end in the retainer. In an air bag for a passenger seat, a container for the air bag is made of a synthetic resin to secure the rear end of the air bag to the container.

Abstract: A fastening system comprises a housing having a closed end and an open end. A first mixable fastener component is disposed within the housing at the closed end and defines a first volume, the first volume being substantially devoid of gas. A rupturable skin overlie the first component proximate the open end for maintaining the first component within the housing.

Abstract: The container (2) consists of two individual cans united by an easy separated connecting ring (4) so that the subject container (2) provide to the consumer with more functions and more flexibilities and due to this special design derive a series combination drink packing system FIG. 6.1 to FIG. 6.4 and people can enjoy more and more different kind of drinks and flavors in a very convenance way just to separate the container and to mix them making a lot of drink choice and to carry this so called container to any where and any time to meet the consumer's need at this Space Age.

Abstract: A system is provided for adhesively attaching a first member to a generally planar portion of a second member. The system includes an attachment clip having a first, generally planar portion and a second portion remote from the first portion adapted for attachment to the first member. A generally planar base is sandwiched between the planar portion of the attachment clip and the planar portion of the second member. An adhesive is located between the base and the planar portion of the second member. A weld is provided between the base and the planar portion of the attachment clip. Therefore, "peel" stresses are eliminated between the base and the planar portion of the second member, as the weld develops a tensile load between the base and the planar portion of the attachment clip.

Abstract: A connector to secure to the end of a cylindrical rod or cylindrical wire. The connector includes an elongated body having a receptacle with a cylindrical wall. A plurality of axially aligned tapered annuluses, coaxial with the receptacle, extend from the cylindrical wall into the body. Each annulus has a cross-section tangentially approaching the cylindrical wall at one end and an arcuate opposite end.

Abstract: A closed back shovel is fabricated by placing a frog within a back-side cavity of a standard open back shovel head. The frog is configured to fill the back-side cavity of the shovel blade. A tang element interconnects the frog and a forward end of a tool handle positioned within a tool receiving socket of the blade, within a handle receiving socket, to secure the tool handle to the shovel head. A process for assembling a closed back shovel includes the steps of securing the tang element to the frog, heating the tang element and placing the frog within the back-side cavity of the shovel blade so that the tang element extends into the handle receiving socket, and aligning a tool handle with the tang element by inserting the handle front end into the handle receiving socket. The tool handle includes a thermoplastic section in proximity into the front end thereof, having an elongate tang receiving channel.

Abstract: The invention relates to a joint connection (3) between two plastic parts (1 and 2), one part being at least partly rotatable in relation to the other part. According to the invention, the joint connection (3) consists of a shell-form outer element (4) on the one plastic part (1) and an inner element (5), at least partly supported in the outer element (4), on the other plastic part (2), both elements (4) and (5) being made by being injection molded one in the other, from one tool.

Abstract: An improved implement including an injection molded thermoplastic handle and an implement head adapted to be placed in the mold in which the handle is to be manufactured in the injection molding process, and in which the implement head is adapted to receive and retain heated thermoplastic material injected under pressure and which the portion for retaining heated thermoplastic material is in communication with the handle, and in which the interface formed between the portion for retaining heated thermoplastic material in the adapted implement head and the thermoplastic material retained thereby forms a bond joining the adapted implement head and the injection molded handle.

Abstract: A process for assembling a hand tool includes the steps of heating an elongated tang element fixed relative to the tool head, aligning a front end of a composite tool handle with a rearwardly extending portion of the tang element, and driving the heated tang element into the tool handle. The tool handle includes a thermoplastic section in proximity to the front end thereof, having an elongate tang receiving channel. The heated tang element is driven into the tang receiving channel such that as the tang element engages the tool handle, the thermoplastic section surrounding the tang receiving channel is softened and flows into intimate contact around the tang element and then hardens as the heat of the tang element is dissipated to hold the tang element in place. In one preferred form, the tang element forms a portion of the tool head which is heated and then positioned in a stationary jig.

Abstract: The invention relates to a connecting assembly for use in the propeller shaft in the driveline of a motor vehicle between the end of a tubular shaft, especially made of a composite material, and a connecting piece positioned coaxially relative to the shaft end. The shaft and connecting piece have connecting structures which inter-fit in the circumferential direction. The tubular shaft is designed to sustain without damage greater impacting force in the longitudinal axial direction than is required to displace the connecting piece relative to the shaft in this direction.

Abstract: An assembly of a tubular shaft member (3) preferably of fiber-reinforced plastics material and a hub member (1), the hub member having formations (5, 6) which engage the internal surface of the shaft member, and further having a surface between the formations so as to define an annular space. Passages communicate with such space at the end thereof of greatest resistance to adhesive flow, for injection of adhesive into the space and release of air therefrom, the configuration of the space causing a flow of adhesive during injection thereof which effectively drives all air out of the space. The space is configured, e.g. by being of varying radial dimension, to provide an increasing resistance to flow of adhesive in the space from one end of the space to the other.

Abstract: A joint assembly, which is particularly useful in the formation of tubular plastic furniture, includes a hole formed in a first member and a second member having a first end which engages the hole. Reinforcing wire members are provided in the joint assembly together with a suitable adhesive and a settable material.

Abstract: A process and apparatus are provided for securing a grip element or handle, preferably of plastic, to a crockery or pottery article. An adhesive is injected under pressure into a passage in the grip element and flows to the surface to be joined to the article. The cured adhesive material holds the grip element to the article both adhesively and by means of a mechanical locking action.

Abstract: A coupling fitting for making joints in reinforcing bars or wires for structural concrete aims to provide a mechanical strength of the coupling virtually equal to the full design strength while providing the ability to increase the strength upto and beyond ultimate tensile strength of the rebar by the addition of resin. To that end the coupling comprises a sleeve for fitting in spaced relation around adjacent portions of rebars to be joined and having positively adjustable engagers threaded through the wall of the sleeve, and profiled engagers to engage said portions. The engagers serve for centering the rebars and the profiling serves to provide a key preferably with both the sleeve and the rebar. It is also preferred to have the positively adjustable engagers configured to bite into the rebars. The spaced relation affords provision for introducing settable resin.

Abstract: A dowel system for securing in a generally abutting relationship two parts or pieces of material having facing surfaces and preformed, aligned annular recesses. The dowel system includes a tubular body having sidewalls which are thinner near the middle of the body than at the ends thereof. The tubular body is dimensioned so that opposite ends thereof may be inserted into respective annular recesses of the two pieces of material, with enough room being left around the sides of the tubular body to allow adhesive to be put in place in the annular recesses to join the tubular body to the sidewalls of the annular recesses.

Abstract: A combination mechanically retained and adhesively bonded attachment structure and method for a guy wire, cable, rod, tube or like member is described which comprises an elongate fitting of preselected external shape having a plurality of axially spaced coaxial bores of respective preselected diameters, the smallest selected to loosely receive the member to be attached, the annular spaces defined between the fitting and member being packed with a finely divided particulate abrasive material and filled with a curable resin to form an adhesive bond between the abrasive material, fitting and member and to define abrasive interfaces between the abrasive material and fitting and between the abrasive material and member.

Abstract: The invention is a close out fitting for installing in a structural element, the structural element having a port extending from a first surface to a second surface thereof, the port countersunk at both ends, and a method of installing the closeout fitting. In detail, the fitting comprises a hollow, tubular sleeve having a flared first end, a flarable second end and internal threads therebetween. The fitting further comprises a plug having a head portion and a shank portion attached to the head portion with the shank portion having external threads.

Abstract: A rod-shaped tension member formed of fiber reinforced composite material is utilized as an anchoring rod in foundation and mining construction, or as a reinforcing member in concrete and prestressed concrete construction. At least, in an axially extending region where it is to receive an anchoring member, such as a rod, the tension member has a continuous helical thread formed of alternating ribs and recesses. The anchoring member has a corresponding thread so that it can be screwed onto the tension member thread. An intermediate layer is provided between the threaded regions of the tension member and the anchoring nut, and is formed of a material affording large plastic deformation relative to the tension member when slight stress increases occur at overload conditions.

Abstract: A method of manufacturing a ball joint serves to reduce the cost for producing the joint. In the method, while a ball portion of a ball stud of the ball joint is being placed in a mold, a socket is cast-molded in such a manner that the socket will form an integral structure surrounding the ball portion. Thereafter, force is applied to the outer wall of the socket by means of a plurality of mill rolls in such a manner that the force causes deformation of the socket so as to allow the ball portion of the ball stud to be slidably rotated relative to the socket.

Abstract: A modular power drive assembly includes a plain carbon driving shaft having an externally splined connection end, and a cast iron yoke having a hub thereon in fixed engagement with said connected end of the shaft. In a preferred form, the hub includes an internally splined mating portion for fixed torsional securement to the externally splined connection end of the shaft. The splined portions are sized to be press-fitted together to provide an interference fit between the splined members. A bonding adhesive is applied between the mating splined portions, and the yoke and shaft members are thereby fixedly secured against axial and rotational movement with respect to one another.

Abstract: In a bicycle frame comprising a plurality of frame members which are selectively joined together at the ends thereof, each of the joints which support the head tube, the seat and the crank housing is a lug joint comprising a plurality of organic fiber layers partially wrapping the joined end portions of the frame members, the fibers composing each layer being oriented at different angles from the fibers in the adjacent layers, and all of these sheets being impregnated with resin which hardens to secure the sheets to the frame members. Web portions of these fiber layers also enclose a portion of the space between wrapped portions of the frame members, and each of these spaces is filled with a suspension of microballoons in hardended resin which cooperates with the web portions of the fibers layers to brace the joined frame members against movement toward each other during use of the bicycle.

Abstract: A bicycle frame having an improved lug design is disclosed. The inner lug has a first external diameter and a second external diameter with the first external diameter being longer than the second external diameter the circumference of the second external diameter has at least two flanges which are shorter than the length of the second external diameter. The circumference about these flanges is equal to the circumference about the first external diameter of the lug. The tube to which the inner lug is joined has a first internal diameter and second internal diameter, the first internal diameter being at the free end of the tube and larger than the other external diameter. The length of the first internal diameter is at least equal to the sum of the length of the first external diameter and the flanges of the inner lug. The second internal diameter of the outer lug is larger than the second external diameter of the inner lug.

Abstract: Method of constructing an assembly having as one element a right circular cylinder with center bore and accurately machined and lapped circular surfaces and perpendicular end faces, and as another element a hollow shaft fitted and joined within said center bore in a manner unable to transmit distorting strain to said cylinder when said shaft has a coefficient of expansion greater than that of said cylinder. The shaft either has an interrupted exterior with severely limited contact areas for joining adhesively to the bore surface or is of other structure that is incapable of straining the cylinder.

Abstract: Method for mounting a plastic armature, particularly in the shape of a handle or an adapter designed to connect other structural parts, to a jar of frangible material like grass, ceramic, glass-ceramic, or the like by adhesively connecting the armature to the outer side of the jar, the armature comprising a shaped part which forms a positive interlock with a rim portion of the jar and the inner side thereof and thus secures the jar against dropping out from the armature upon a possible loosening of the adhesive connection, characterized in that an armature is used which comprises an extension of thermoplastic material which with projects inwardly over the rim of the jar when the armature is put into place, and in that during or after the making of the adhesive connection of the armature, the extension is softened by heating, deformed into the interlocking shaped part, and re-hardened by cooling.

Abstract: A camshaft for an internal combustion engine comprising a metal cam, a shaft inserted into a through hole formed in the cam and resin poured between the cam and the shaft to join them. The cam is formed with plural grooves which are formed in the inner periphery of the hole in parallel with the shaft and into which the resin is poured. The groove is formed fanwise so that a sectional shape of the groove is wider as it approaches the outer periphery of the cam. Thus, when the resin which is filled into the grooves at high temperature is cooled naturally and contracts, since the resin bites the cam, gap and failure of contact are not produced between the cam receiving rotational force and the resin when the camshaft is operated for the internal combustion engine.

Abstract: A piston and cylinder assembly for the annular type in which the cylinder defines an annular housing chamber slidably receiving an annular piston. The inboard end of the annular piston is enlarged to define an enlarged annular inboard end edge and an annular seal is positively secured to the enlarged inboard end edge of the piston and sealingly engages the associated cylindrical surfaces of the housing member. The enlarged annular inboards end edge of the piston is convoluted to maximize the area of the bonding interface between the piston and the seal so as to preclude extrusion of the seal and twisting of the seal during operation of the piston and cylinder assembly.

Abstract: A clean room ceiling grid system having a detent means for loading filter panels into ceiling grids from a clean room. The system is operable to permit removal of the filter panels by use of a filter panel removing tool. More particularly, this clean room ceiling grid system requires no plenum space use above the grid members for either installation or removal of filter panels. The system also includes means for hermetically sealing the interface of connected ceiling grid members and means for substantially laminar flow of filtered air in clean rooms.

Abstract: A method of arranging a splice sleeve to receive a reinforcing bar in a mold for use in manufacturing a precast concrete member by providing an elastic body having a through opening hole generally extending through the longitudinal center of the body, in the interior hollow of the sleeve by inserting an extending bar with a pull-out preventing portion at the end of the bar, into the through hole of the elastic body so as to form the bar projecting from the inside of the mold to the outside of the mold, and by drag pulling the projecting extending bar toward the outside of the mold so as to press the elastic body, thereby to fix the elastic body to the interior wall of the sleeve, and the elastic body being compressed so as to get in close contact with the interior surface of the sleeve, thereby to fix the splice sleeve to the mold.

Abstract: An end connection for a shaft made of composite material, which accommodates for differences in stiffness, thermal expansion, chemical resistance between the shaft and the member connected thereto and operates under oscillating torque, thrust, and bending loads, and also provides for manufacturing flexibility in enabling the shaft and connection to be produced as separate parts which are formed when final assembly is to occur. The connection has a male insert which is inserted into the end of the composite shaft. Axial and circumferential grooves in the surfaces of the male insert and the shaft. These grooves are aligned to form circumferential and axial keyways which intersect each other. Material is injected into the keyway and polymerizes to form structural keys which transmit the thrust and torque, while locking the insert member and the shaft permanently together. The bending loads are transmitted through the tight fit extending axially between the shaft, insert member and keys.

Abstract: A method for the production of frames from rigid plastic profiles for use on refrigerator cabinets and in particular on chest freezers, which comprises forming the plastic profiles, mitering and welding the edges of the plastic profiles to form a frame having sharp-edged corners, and rounding at least one of the sharp-edged corners by means of thermo-forming.The invention also comprises the finished frame thereby obtained and its application in the field of refrigerator cabinets and in particular, chest freezers.

Abstract: A windshield wiper shaft is mounted in a bearing bushing, wherein the bearing bushing and the wiper shaft rest against each other with conical bearing surface portions to compensate for possible radial play. This is important in constructions in which the bearing bushing and the wiper shaft are injection-molded from plastics material.

Abstract: A splice sleeve for connecting overlapping reinforcing bars utilized in various types of structures in which steel reinforcing bars are utilized and it is desired to connect the overlapping end portions of the reinforcing bars. The splice sleeve includes a rigid tubular sleeve receiving the overlaped ends of the reinforcing bars with the tubular sleeve being filled with hardable material to resist axial tension exerted on the reinforcing bars. In one embodiment, one end of the sleeve is closed by a rubber grommet having an opening receiving one of the reinforcing bars and the other end of the sleeve may be outwardly flared or trumpeted and provided with a ring welded thereto for receiving an end of one of the reinforcing bars with the sleeve confining the hardenable material and resisting radial outward forces imparted to the hardenable material when axial tension is exerted on the reinforcing bars.

Abstract: An invisible connection for faced parts, in particular for furniture. The adhesive for the connection is hermetically enclosed in a sheath consisting of flexible or easily breakable material. The sheath of adhesive is introduced as an independent component into the borehole of the connection, the sheath being destructible on driving-in or pressing-in the connecting member.

Abstract: A method and an apparatus are described for anchoring cables, bundles of parallel or standard wire, or the like, of preferably high-tensile steel wire. At least one end of the cable or the like is introduced into a fixed anchoring socket and sealed with a pourable material. In order for the anchoring apparatus to have improved properties under static stress, and in particular under great dynamic stress, without requiring additional structural safety features, while enabling lower-cost manufacture, it is provided that the bundle be twisted and the bundle or cable opened for some distance from the associated end in such a manner that the wires or strands extend uniformly all the way through the conical inner region of the anchoring socket. Further, a metallic casting material is poured into the anchoring socket between the opened wires or strands, and a direct metal-to-metal joint is established between the metallic casting material and the wires or strands of the cable or bundle.

Abstract: A shaft assembly comprises a shaft having at least one small diameter portion located on the way in the axial direction thereof, and at least one member mounted to the outer periphery of the small diameter portion of the shaft rotatably and/or movably in the axial direction. The shaft assembly is produced by first forming the member on a large diameter portion of the shaft and then moving the member from the large diameter portion to the small diameter portion. The member moved to the small diameter portion is mounted to the small diameter portion rotatably and/or movably in the axial direction by the shrinkage thereof.

Abstract: This invention relates to a tool with at least one wear-resistant hard metal part which serves to process production pieces, stones, or the like, wherein the hard metal part is firmly connected with a metallic carrier by solder located in at least one solder aperture. In order to reduce the danger of formation of tension cracks in the hard metal part, the invention provides that at least one predetermined weak point is created in the solder aperture.

Abstract: The disclosure relates to a reinforcing bar coupling system wherein reinforcing bars or wire are coupled for structural concrete by applying to adjacent rod or wire portions a material, e.g. epoxy resin settable to form a structurally sound joint. The material is applied by injection into a sleeve surrounding the adjacent wire portions.

Abstract: In the present invention a suitable end fitting is provided for fiberglass or plastic rods wherein the interior of the end fitting is defined by a chamber having an opening in an end and a side wall defined by a plurality of parabolic curved compression grooves and alternate spaced neck members wherein the angle between each of such parabolic curve compression grooves and the neck members increases in said chamber from the opening to the end of said chamber.

Abstract: A sucker rod construction including a connector member being formed to define a rod receptacle having a closed axially inner end and an open axially outer end. The rod receptacle has a plurality of axially spaced, tapered annular surfaces. The end of a cylindrical fiberglass rod is received within said rod receptacle through the outer end and cooperates therewith to define an annular chamber between the outer surface of the end of the rod and the tapered annular surfaces. A bonding material is positioned in the annular chamber and bonds the outer surface of the end of the rod and the tapered annular surfaces. Each of the annular surfaces has an angle of taper with respect to the outer surface of the fiberglass rod, and each angle of taper is progressively less toward the open end by at least one and one-half degrees.

Abstract: An improved welded structural joint in the form of a fabricate tee and method for making same is described which comprises a transverse member and a strut member abutting at one end to the transverse member intermediate its ends, and one or a pair of U members disposed around and welded to the transverse and strut members, each U member having an arcuate portion intermediate its ends conforming to the outer surface contour of the transverse member and a pair of straight portions near its ends defining a pair of parallel legs having predetermined length and spacing and being welded lengthwise to the strut member. The transverse and strut members may be solid or tubular and of circular, rectangular or other suitable cross section, and of substantially any respective size. The longitudinal axes of the transverse and strut members may intersect at substantially any angle, or the members may be joined tangentially.

Abstract: A frame joint for bicycles and the like includes a stub insert consisting of a base, a stub protruding from the base, and an annular shoulder at the junction between the base and the stub; a connecting member having a tubular end with an annular end face telescoping over the stub in a press fit; adhesive bonding the tubular end to the stub; and an annular collet positioned on the stub between the end face and the shoulder. The collet includes an inner end having a first lip portion which extends about and overlaps a periphery of the base adjacent to the shoulder and an outer end having a second lip portion which is beveled in a concave fashion to overlap and receive the end face of the connecting member. The first and second lip portions are joined by a continuous outer wall having a diameter greater than that of the tube end and the base, and an interior wall extending between the first and second lip portions having a diameter less than that of the tube end and base.

Abstract: A concrete structure including a rigid three-dimensional lattice of concrete bars which are interconnected at nodes. The lattice is constituted by an assembly of prefabricated cast blocks, in which each block comprises a node and a plurality of arms (14) radiating from the node. Each arm has at least one longitudinal socket with an opening in the free end of the arm, and the arms of two blocks are assembled in aligned end-to-end pairs to constitute the bars of the lattice. The sockets of assembled arms are in alignment and contain a common metal reinforcing member, and the junction zone of the arms is surrounded by a clamping sleeve, with said sockets being filled with hardened mortar. The said lattice is prestressed by prestress cables passing outside the bars of the lattice and fixed to some nodes of the lattice.