The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 18, 1987
Filed:
Mar. 13, 1986
Hochtief Aktiengesellschaft Vorm. Gebr. Helfmann, Essen, DE;
Abstract
An apparatus for making a tunnel lining from concrete in a single operation with a tunnel excavator comprises a tunnel lining form consisting of a plurality of tunnel lining form segments and a form front adjacent the tunnel excavator and a tunnel lining circular space between the form and the ground. In order to heat the concrete as it is pumped into the tunnel lining circular space to accelerate hardening, transmitting antennae for electromagnetic radiation are mounted in the tunnel lining form segments and/or the feed pipes for the concrete. Similarly a process for making a tunnel lining from concrete comprises pumping concrete into the tunnel lining circular space and accelerating the hardening of the concrete by heating it with electromagnetic radiation. The tunnel form is rapidly repositioned after the concrete being hardened reaches a sufficient strength.