Abstract: In the formation of finished slide surfaces for slide rails on a track for an electromagnetically levitated vehicle, the track is constructed as a girder-like beam with the slide rails located on cantilevered parts of the upper surface of the beam. The beam can be formed of prestressed concrete. Initially the slide rails are provided with a height oversize. The height oversize part of the slide rails is removed and the slide surface of the rails are finished to the desired degree. The height oversize part is removed by cutting and grinding devices mounted on a machine frame movable over the upper surface of the track. The machine frame is adjustable in the vertical direction from a datum plane formed by the lower surfaces of support stators secured to the undersides of the cantilevered parts of the track. The machine frame rides on the upper surface of the beam and is in contact with the lower surfaces of the support stators.

Abstract: An anchoring device, such as a rock anchor, includes an anchor rod with force transmission ribs projecting outwardly from its outside surface. An anchor nut is in threaded engagement with the rod and has at least an axially extending portion formed of a material having lesser strength than the material of the rod. The anchor nut has at least two axially extending portions spaced apart by cuts through the nut, which cuts extend transversely of the nuts central axis. The portions follow one another in the central axis direction with at least the portion closer to the body into which the anchor rod extends having the lesser strength. The nut portions are dimensioned so that the portion closer to the body loses its force locking engagement with the ribs on the rod and its threads shear off when a predetermined load is exceeded. The nut portions are interconnected by narrow webs remaining after the cuts are made in the nut separating the portions.

Abstract: A corrosion-protected tension member, such as a tendon for prestressed concrete with post-tensioning, is made up of a bundle of individual tension elements, such as strands, arranged within a tubular envelope. The tension member extends between anchoring devices, each forming an anchor region for the tension member with a free region located between the anchor regions. In the free region, the tubular envelope is formed of a sheathing tube. Each individual element is located within a separate sheathing duct, and a corrosion-protection mass fills the space within the ducts about the elements. The open volume within the sheathing tube around the sheathed elements is filled with cement mortar. In the anchor regions, the tubular envelope includes an anchor tube enclosing an anchor pot. The anchor pot has a base with openings through which the individual elements pass in a sealed manner. The anchor pot is filled with a corrosion-protection mass.

Abstract: To produce threaded steel tension members, steel is used with a C-content of 0.50 to 0.80%, preferably 0.75%, a Si-content of 0.20 to 0.50%, preferably 0.25%, and a Mn content of 0.30 to 0.80%, preferably 0.60%. Exiting from the rolling heat at the outlet side of the finishing stand after hot rolling, the tension member or rod is subjected to surface quenching by a cooling medium, preferably water, so that the steel in a rim zone R.sub.1 is transformed immediately and completely into martensite, while the heat content remaining in the core zone K.sub.1 does not effect a tempering of the martensite rim zone during the subsequent cooling beyond the range of the intermediate stage.

Abstract: In pulling or pushing steel tendons, such as strands of steel wire through ducts positioned in a concrete structural member, the ducts are sheathing tubes encased in the concrete of the structural member. To limit the friction acting on the tendon as it is displaced through a duct, forces acting in the axial direction of the duct or vibrations acting transversely of the axial direction of the duct are applied directly to the tendon. These forces are applied at recesses in the structural member accessible at its outside surface. The friction acting on the tendon is compensated by the axially directed forces and the application of vibrations greatly reduces the coefficient of friction. These forces acting on the tendon can be combined and are particularly useful for moving tendons around small radius curves and through large redirecting angles.

Abstract: In the formation of finished slide surfaces for slide rails on a track for an electromagnetically levitated vehicle, the track is constructed as a girder-like beam with the slide rails located on cantilevered parts of the upper surface of the beam. The beam can be formed of prestressed concrete. Initially the slide rails are provided with a height oversize. The height oversize part of the slide rails is removed and the slide surface of the rails are finished to the desired degree. The height oversize part is removed by cutting and grinding devices mounted on a machine frame movable over the upper surface of the track. The machine frame is adjustable in the vertical direction from a datum plane formed by the lower surfaces of support stators secured to the undersides of the cantilevered parts of the track. The machine frame rides on the upper surface of the beam and is in contact with the lower surfaces of the support stators.

Abstract: On a track for electromagnetically levitated vehicles, side guide rails are positioned on and secured to a beam-like support member forming the track by an apparatus made up of a transportation frame extending in the long direction of the support member and by installation truss frames located on and extending transversely of the transportation frame. Side guide rail installation arms are pivotally mounted on the installation truss frames. With the arms in an outward position the guide rails can be placed on and held by the arms. By pivoting the arms inwardly the side guide rails can be located along the outer sides of the support member. By raising the installation truss frame, the guide rails can be located relative to stators mounted on the underside of the support member. In addition, the final position of the guide rails can be established by moving the installation truss frames transversely of the transportation frame and relative to a plate strip on the upper surface of the support members.

Abstract: To secure roadways and wall surfaces of open cuts and tunnels, a rock anchor assembly is inserted into and secured within a borehole in a receiving material. The rock anchor assembly is made up of an axially elongated tension member laterally enclosed in part by an axially elongated sheathing tube so that the tension member projects outwardly from the opposite ends of the sheathing tube. In the insertion direction, the leading end of the sheathing tube is secured in tension-resistant locked engagement with the tension member. Initially, a hardenable adhesive material is injected into a borehole and then the assembled tension member and sheathing tube are inserted into the adhesive material so that the unsheathed end of the tension member is anchored in the base of the borehole. The trailing end of the sheathing tube has a flange which bears against a anchor plate in contact with the surface of the receiving material in which the borehole is formed.

Abstract: A tendon for use in prestressed concrete is made up of a plurality of individual elements such as strands of steel wire arranged in a uniform array around and spaced radially outwardly from a center point. A spacer for the tendon includes a star-shaped base formed by arms extending radially outwardly from a central part. The central part and the arms define triangularly shaped openings for receiving one or a number of the tension elements. An intermediate part is positionable within the triangularly shaped openings for separating the elements located within the opening. The intermediate parts have a radially extending web and a flange extending transversely of the web for dividing the opening into separate spaces for each tension element. During assembly, the base is inserted into the tension member for separating the tension element and then the intermediate parts are inserted for spacing the elements from one another.

Abstract: A steel pipeline to be driven through an earth section without disturbing the overlying earth is made up of a plurality of serially arranged axially extending pipe sections each having a leading end and a trailing end. The leading end of each pipe section abuts the trailing end of the pipe section previously driven into the earth section. A pressure-tight pipe connection between the abutting ends of the pipe sections is formed by a steel ring secured within the trailing end of the pipe section and projecting axially out of the trailing end. The steel ring has an outside diameter smaller than the inside diameter of the section. The leading end of the next pipe section has an elastic material sealing ring secured to its inside surface with the sealing ring projecting radially inwardly beyond the outside surface of the steel ring.

Abstract: An apparatus for forming a radially outwardly directed bulge in an axially extending stranded steel wire cable for use as an anchor in a concrete structural component includes a frame with a pair of side walls. A clamping device is mounted on one end of the frame for gripping the stranded cable. The clamping device has two displaceable clamping jaws connected to counter jaws by articulated levers for moving the clamping jaws into the closed or clamped position. The clamping jaws are closed by a piston-cylinder unit mounted in the frame. Spaced from the clamping device on the frame is a sliding carriage with a thrust member into which one end of the stranded cable is inserted. The sliding carriage is connected to the piston-cylinder unit.

Abstract: A wedge anchorage for an axially elongated tension member, encased in and arranged to prestress a concrete structure, includes an anchor member with a conically widening surface where a wedge seats for securing the tension member in the tensioned state with a cap arranged to fit in locked engagement with the end of the anchor member through which the tension member extends out of the concrete structure. The cap has a cover wall extending transversely of the axial direction and spaced from the anchor member. An opening is provided in the cover wall through which the tension member extends out of the concrete structure. A spring or other biasing member is located within the cap for limiting axial displacement of the wedge when the tension member is stressed in tension. This arrangement avoids the formation of a recess in the surface of the concrete structure from which the tension member extends and the need for a filler member for sealing off the recess when the prestressing operation is completed.

Abstract: For the installation of an anchor member at a location below a water level through a retaining wall into a soil formation for supporting the wall, a drill mount is pivotally mounted about a horizontal axis on a retaining member secured to the wall. The drill mount can be pivoted between a drilling position inclined downwardly toward the wall and an upwardly extending loading position where the drill mount is accessible above the water level. A cable line secured to the drill mount pivots it between the drilling and loading positions. A drilling machine is displaceable on a sliding carriage along the drill mount. A drilling tool inserted into the drilling machine is used to drill an opening through the wall. Subsequently the drilling tool is replaced by a borehole pipe and the pipe is driven through the wall opening into the soil formation.

Abstract: A closed ring-shaped reinforcing member for use in a concrete structure and which is stressed by annular tensile forces, such as a bell-shaped anchoring body for a prestressing member used in a prestressing concrete structure, is provided around the radially outer surface with a coating of a material which is elastically or plastically deformable under compression. The reinforcing member can deform under the action of annular tensile forces which cause it to stretch, but the presence of the deformable coating on its outside surface prevents the transfer of such deforming forces to the concrete structure, since otherwise such forces could result in the formation of cracks in the structure.

Abstract: A support system for a multiple-span bridge constructed of reinforced concrete or prestressed concrete includes a primary structure and a secondary structure. The primary structure bridges the spans between intermediate supports or between an abutment and an adjacent intermediate support and includes serially arranged support members elongated in the long direction of the bridge. The width of the support members is a fraction of the full useful width of the bridge. The secondary structure forms the roadway slab and is supported on the primary structure. The secondary structure is made up of serially arranged individual roadway sections extending in the long direction of the bridge. The roadway sections are supported by bearing members resting directly on the support members of the primary structure with the roadway sections being closely spaced in the elongated direction of the bridge as compared to the spans between the intermediate members and the abutments.

Abstract: A tension member for use as a rock anchor or the like has a plurality of steel wires embedded in a tubular member with a central bore and formed of a hardenable plastics material, such as a synthetic resin. The outer surface of the tubular member is profiled such as in the manner of a screw thread so that an anchor member can be threaded on to the tubular member. The steel wires are arranged symmetrically around the axis of the tubular member for carrying the load transmitted by the tension member. If there is a displacement of the rock anchored by the tension member then both the tension and shearing stresses acting on the wires can cause individual wires to be displaced from the tubular member into its central bore. As a result, the flexibility of the tension member is increased and the most highly stressed wires can move out of the tubular member into its central bore.

Abstract: A prestressed grouted anchor has a portion of an axially extending prestressed tension member grouted in a receiving material while the remaining portion of the tension member extends from the grouted portion. The remaining portion is separated from the grouted portion at a selected breaking point by reducing the tensile strength of the tension member as the result of exposing it to the action of heat, such as developed in an exothermic chemical reaction. If the tension member is prestressed and the resulting elastic elongation is maintained during the heating action with the elongation being greater than the elongation required under the heating action for effecting the severing of the tension member, then with progressive heat the tensile strength of the tension member is reduced and the elastic elongation progressively changes to plastic elongation with the tension member finally severing automatically at the selected breaking point.

Abstract: In the assembly of a tension tie member between spaced anchors when the tie member is made up of a number of individual tension elements, such as steel wires, steel strands or the like, enclosed within a tubular sheathing, the tension elements are inserted individually and successively between the anchors and it is necessary to insert the annular wedges which anchor each element before the tension elements are released from a threading device. To prevent the annular wedges from prematurely entering into the boreholes in the anchor plate, an auxiliary plate is positioned spaced from the anchor plate. The auxiliary plate has at least one through borehole axially alignable with the boreholes in the anchor plate. A tubular section is secured to the auxiliary plate and forms an extension of the borehole therein. An annular wedge to be inserted into one of the boreholes and the anchor plate can be held on the tubular section by resiliently expanding the wedge about the outer surface of the tubular section.

Abstract: A tie member includes at least one tension element, such as a steel wire or strand, enclosed within a tubular sheathing. An anchoring unit is located at each end of the tie member for transmitting the tension force to a part of a structure. Each anchoring unit includes an anchor plate with at least one conically shaped bore so that a tension element can be secured in the borehole by a multi-part annular wedge. To provide additional corrosion protection and improve fatigue strength in the anchorage, the tension element is enclosed within a coating of a synthetic resin for its entire length. The inside surface of the wedge is shaped between the ends with a series of coarse or rough teeth with the tips rounded off.

Abstract: An anchoring apparatus for insertion into a borehole in a rock stratum for supporting the rock surface or wall, such as in a rock tunnel or rock excavation, includes a tension member in the form of an axially elongated steel rod with force transmission ribs on its outer surface and an anchoring element, such an anchoring nut, engageable with the rod. The anchoring element has an inside surface with inwardly extending projections and the adjacent flanks on the projections form grooves within which the force transmission ribs engage. The anchoring element is formed of a higher strength material than the rod. When a predetermined axially extending tension force acting on the rod is exceeded, relative movement takes place between the anchoring element and the rod. The flanks on the projections on the anchoring element in contact with the ribs on the rod shear off a portion of the ribs contacted.