REINFORCED ROADBED STRUCTURE, REINFORCED ROADBED CONSTRUCTION METHOD, AND INTRUSION METHOD OF INTRUSION BODY INTO NATURAL GROUND UNDER ROADBED

• Main Authors: TOKUMITSU YOSUKE, HOSOKAWA YOSHIO, HANAWA SHIYOUTARO, TAKAGI SHINICHI
• Format: Patent
• Language: English
• Published: 07.03.2000
• Edition: 7
• Subjects: EARTH DRILLING; EMBANKMENTS; EXCAVATIONS; FIXED CONSTRUCTIONS; FOUNDATIONS; GALLERIES; HYDRAULIC ENGINEERING; LARGE UNDERGROUND CHAMBERS; MINING; SHAFTS; SOIL SHIFTING; TUNNELS; UNDERGROUND OR UNDERWATER STRUCTURES

PROBLEM TO BE SOLVED: To improve an execution property by forming a roadbed with an upper roadbed and a lower roadbed having smaller strength than it, and specifying the unconfined compressive strength of each roadbed. SOLUTION: A track bed 3 made of a ballast material is provided on a roadbed 1 on a subgrade 2, and rails 5 are installed on it via crossties 4. The roadbed 1 is constituted of an upper roadbed 6 and a lower roadbed 7 with smaller strength than it, the unconfined compressive strength σ28s (material age 28-day strength) of the roadbed 6 is set to 20 kgf/cm2 or above, and that of the roadbed 7 is set to 4-10 kgf/cm2. When a lining element 8 is intruded into the natural ground while the natural ground is excavated by an excavator 9, the upper section of the element 8 is overlapped on the roadbed 7 by the prescribed quantity. The element 8 is easily intruded because the strength of the roadbed 7 is small, and the deformation of the element 8 and a cave-in caused by the push-up of the roadbed 1 or the occurrence of a void can be prevented. No track maintenance work is required after the intrusion work of a tunnel lining material, and the occurrence of a new trouble caused by roadbed reinforcement can be prevented.