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:
May. 14, 1985
Filed:
Sep. 28, 1982
Dieter Rebhan, Gelting, DE;
Linde Aktiengesellschaft, Wiesbaden, DE;
Abstract
Tunnels are constructed by freezing soil and removing frozen soil between starting and end shafts of the tunnels. Tunnels are driven in an uncomplicated manner in rapidly changing soils without auxiliary construction means. A hole is bored in or near the planned axis of the intended tunnel between starting and end shafts. A soil freezing work pipe is inserted into the hole. The pipe is cooled by a cooling agent. The soil freezing work pipe continues to be cooled until an ice and frozen soil mass has formed around the work pipe, which frozen mass has a diameter which is larger than that of the planned tunnel. Frozen soil is subsequently excavated, leaving a frozen soil lining, which is immediately supported by a primary support lining or a permanent lining.