| 摘要 |
PURPOSE:To know the thickness and strength of the back filling injection material speedily and accurately by fitting a tip cone incorporated in a pressure sensor in the back side of a segment through a hole bored in the segment, and measuring the intrusion depth position and intrusion resistance value of the cone and hydraulic pressure. CONSTITUTION:When a duplex tube rod 6 is intruded into the segment 1 to its back side through the grout hole 13 bored in the segment 1, a styrene foamed body 14 is charged in the hole 13 right after the segment is assembled and the hole is blocked with a grout cap 15, thereby preventing the back filling injection material 3 from leaching out into the hole 13 and impeding measuring operation. A hole which is large enough to insert the tip cone 7 is bored in the foamed body 14 with a drill from above the cap 15 and the cone 7 of the duplex tube 6 is pressed in until it reaches the injection material 3. Further, a displacement gauge 10, load cell 8, and output cable 16 of the hydraulic pressure sensor in the cone 7 are connected to a recorder and the rod 6 is intruded into the injection material 3 by pressing a propulsion handle 9 to calculate the thickness of the injection material 3 from respective measured values. |
