摘要 |
<p>A method of repairing leaks in underground sewer pipe which includes the steps of closing the pipe at an upstream and a downstream position forming an enclosed section, filling the enclosed section with grout under pressure from a source and causing said grout to ooze through the leaks, replacing the grout in the enclosed section with a non-hardening liquid under pressure which prevents the grout which has oozed through the leaks from passing back into the enclosed section, and removing the non-hardening liquid from the enclosed section after the grout has hardened and sealed the leaks.</p> |