Upcon Corporation

Nobukazu Matsudo

Koji Kawaguchi

An object of the present invention is to provide a method for accurately modifying a concrete slab on subsided ground by injecting an expandable resin below the concrete slab more than once, which also allows for easy control of the work process. The method of the present invention as a means for resolution includes performing the following steps: on a concrete slab in an area including a region where ground subsidence has occurred, determining points to drill injection holes for injecting an expandable resin at a pitch of 0.5 to 2.0 m in a grid pattern or a staggered pattern; injecting an expandable resin below a point where the subsidence of the concrete slab is severest and expanding the expandable resin to push up the concrete slab at most 30 mm more than once.

Method for modifying concrete slab on subsided ground

A method for correcting the tilt of adjacent concrete slabs on subsided ground and connected at a joint part by tie bars or dowel bars caused by the subsidence of the joint part. The method comprises pushing up a tilted concrete slab by: drilling an injection hole for injecting an expandable resin in one concrete slab at a point 10 to 200 cm away from the joint part and also in the other concrete slab at a point 10 to 200 cm away from the joint part, the point in the other concrete slab being on a line that is orthogonal to the joint part and has the point in the one concrete slab thereon; and simultaneously starting an operation of intermittently injecting an expandable resin from both of the injection holes wherein the expandable resin expands below both of the concrete slabs.

Method for correcting concrete slab tilting on subsided ground

An object of the present invention is to provide a method for accurately modifying a concrete slab on subsided ground by injecting an expandable resin below the concrete slab more than once, which also allows for easy control of the work process. The method of the present invention as a means for resolution includes performing the following steps: on a concrete slab in an area including a region where ground subsidence has occurred, determining points to drill injection holes for injecting an expandable resin at a pitch of 0.5 to 2.0 m in a grid pattern; injecting an expandable resin below a point where the subsidence of the concrete slab is severest and expanding the expandable resin to push up the concrete slab at most 30 mm more than once.

Growing community of inventors

Kawasaki, Japan

Nobukazu Matsudo