Abstract: A switch cross tie is made in a mold having a base plate formed with a plurality of holes in a predetermined pattern corresponding to a particular type of concrete switch cross tie by first overlying the entire base plate of a mold with a covering sheet provided with markings in a pattern corresponding to that of the holes needed for another particular type of concrete cross ties. This covering sheet overlies and blocks all the holes formed in the base plate and it is fixed in place atop the base plate. Then the operator or a computer-guided drill press cuts through the covering sheet and into the base plate at each of the markings to form thereat a respective new hole. Each such new hole is fitted with an anchor, and the mold is filled with concrete over and around the anchors with the covering sheet blocking all the holes other than the new holes. It is important that the covering sheet be sufficiently strong to inhibit entry of concrete through it into any of the holes other than the new holes.

Abstract: A switch cross tie is made in a mold having a base plate formed with a plurality of holes in a predetermined pattern corresponding to a particular type of concrete switch cross tie by first overlying the entire base plate of a mold with a covering sheet provided with markings in a pattern corresponding to that of the holes needed for another particular type of concrete cross ties. This covering sheet overlies and blocks all the holes formed in the base plate and it is fixed in place atop the base plate. Then the operator or a computer-guided drill press cuts through the covering sheet and into the base plate at each of the markings to form thereat a respective new hole. Each such new hole is fitted with an anchor, and the mold is filled with concrete over and around the anchors with the covering sheet blocking all the holes other than the new holes. It is important that the covering sheet be sufficiently strong to inhibit entry of concrete through it into any of the holes other than the new holes.

Abstract: In the case of certain series-produced finished parts, such as switch cross ties, the precision of the assembly of components is of decisive importance. The components should neither be damaged nor should their position be changed during assembly. During the assembly process, they have to be nonslidably fastened in the casing, at the same time the fastening should not damage the finished part or the component during the movements occurring in the hardening process or during the removal of the casing from the finished part. The temporary connection uses a blind rivet which can be introduced and driven in from above with its stem through the bore of the bottom plate carrying the component, as well as through the bore determining the position of the component in the casing plate, and is solidly anchored on the outside of the casing plate by rivet-head-like enlargement.

Abstract: In the case of certain series-produced finished parts, such as switch cross ties, the precision of the assembly of components is of decisive importance. The components should neither be damaged nor should their position be changed during assembly. During the assembly process, they have to be non-slidably fastened in the casing, at the same time the fastening is not allowed to damage finished part, respectively the component, neither during the movements occuring in the hardening process, nor during the removal of the casing from the finished part, i.e. a fastening device has also to be easily detachable.

Abstract: In casings for switch cross ties, the bottom plate 3 serves at the same time as a pattern for the position of the construction components. As a rule, a new casing is prepared for each series of cross-ties type. In small series with various positions of the construction components it is economical to use the bottom plate repeatedly. This is done by providing the bottom plate, prior to its insertion in the casing, with holes (A,B,C) for several types of finished parts, by provisionally closing the unnecessary holes by suitable means and by finding the combination of holes required for the production of a certain type of finished part through a certain searching procedure and freeing them of their provisional closing means.

Abstract: For the production of cross ties for switches, made of concrete in a prestressing fixture, a recoverable device for the emplacement of tubular components is built into the bottom of the concrete form for the tie, which comprises a pin and a nipple inserted detachably into its bottom. The nipple can be inserted into a corresponding bore of a base plate. The bore determines the position of a tube in the cross tie, has an upper and a lower stop with which it is anchored in the pin or the base plate, respectively, and can be firmly tensioned upon the base plate.

Abstract: A tunnel construction made of tubbings forming a lining or casing for a tunnel includes a plurality of contact points between adjacent tubbings. These contact points comprise adhesive material acting to connect adjacent tubbings to each other at predetermined points. The contact points are distributed around the circumference of the tubbing rings at predetermined locations which depend on the type of the tubbing used and also on the points of pressure application by the driving shield of a tunneling or heading machine. The present tubbings have recesses in their surface facing into the tunnel whereby the recesses have a substantially trapezoidal shape to form three ribs extending substantially in the direction of the longitudinal tunnel axes.