JP3447050B2 - Widening shield device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield apparatus for excavating a cross section of a part of a section by widening the section. 2. Description of the Related Art In a shield tunnel, it is necessary to enlarge the cross section of only a part such as a branch connection of a private company. For example, when connecting a cable from an orthogonal direction in a common groove, the cable is bent with an appropriate radius, so a widened portion is required as a space for the cable, and when connecting a cable, The same is true for Further, for example, providing a pump room in an underpass (subway, underground expressway, etc.) also requires a widened portion. [0003] Recently, it is difficult to occupy the ground for a long period of time, and it is desired to perform construction only from underground without using the ground. Normally, underground tunnel excavation work is performed by a shield machine, and for excavation of such a widened part, after constructing a shield tunnel with a standard diameter section, remove the segment of the widened part once assembled and expand it The shield method and the NATM method are used. That is, in the conventional enlarged shield method,
As shown in Figs. 3 and 4, a primary shield is constructed with a standard diameter (Fig. 3). Is built, and the circumferential shield is set at the starting base, and the circumferential shield excavation and assembly of the circumferential segments are repeated. Then, the enlarged shield L divided and brought in at the base cut and opened by the circumferential shield is assembled (FIG. 4), the excavation of the enlarged shield L, the assembly of the enlarged segment 6 and the disassembly and removal of the primary segment 2 are repeated to form the enlarged shield L. Propulsion is performed to widen a predetermined range (FIG. 5). In the NATM method, after the primary shield lining, the upper half segment is removed and the upper half excavation and primary spraying are performed, and then the lower half segment is removed and the lower half excavation and primary spraying are performed. Do. And lining is performed by excavating and placing inverts. In addition, JP-A-58-98595,
JP-A-59-102095, JP-B-63-462.
No. 35, Japanese Patent Publication No. 3-41637, Japanese Patent Publication No. 5-
Japanese Patent Application Publication No. 20556 and the like disclose the technique of the enlarged shield method. However, in these conventional methods, the excavation work by the shield machine and the excavation work of the widened portion are performed separately, which is inefficient. SUMMARY OF THE INVENTION Accordingly, the present invention has improved the conventional method in which the primary shield excavation is preceded and the widened part is separately excavated thereafter, so that the shield capable of simultaneously constructing the widened part efficiently can be improved. It is intended to provide a device. According to the present invention, there is provided a shield device for excavating by enlarging a cross section of a part of a section.
A shelter (3) is installed at the place where the tail section is widened and the excavation is performed. In the shelter (3), a plurality of shelters (M) are circumferentially installed at the ends of the standard segments (2). Propulsion jack for propelling (4)
And another propulsion jack (4a) provided at the rear end of the widening section segment (6) and used for propulsion of the widening section segment (6). The shelter (3) is propelled by the shield machine (M). A wide-width segment (6) is incorporated therein, and a standard-diameter thrust transmission member (8) is provided. A reinforcing member (7) for connecting the wide-width segment (6) and the thrust transmission member (8) is provided. ) Is provided. As described above, according to the present invention, the tail portion is excavated to the predetermined position where the widening start position is reached by the shield work of the standard diameter. Excavation of the part is carried out simultaneously with propulsion by the propulsion jack. This excavation is performed alternately with the segment assembly for each predetermined distance (for one ring), and after the construction of the predetermined widening section, the work is returned to the standard diameter shield work. Therefore, the excavation of the widened portion is not performed after the excavation of the standard diameter portion as in the conventional construction method, but the standard diameter shield and the widened portion are excavated at the same time, and efficient construction is possible. . The cross section of the widened portion is not limited to a concentric circle, and can be applied to a cross section of an arbitrary shape such as a non-concentric circle, a horseshoe, or a rectangle. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the shield machine M at the widening start position, showing a state where the standard segment 2 is released from the tail portion with the tail portion as the starting point for widening, and the shelter 3 is installed by widening excavation. Note that, depending on the ground conditions, the shelter installation portion indicated by reference symbol X is subjected to column improvement, and the propulsion portion indicated by Y is subjected to ground improvement such as chemical injection. Then, under the shelter 3, excavation of the widened face K is performed, and a plurality of propulsion jacks 4 for propelling the shield M are installed at the rear end of the segment 2 in a circumferential manner. A propulsion jack 4a is also provided at the rear end. In addition, for promotion of shield M, usually,
The jack 4 at the rear end of the segment 2 is used, and the jack 4 a at the widened portion is used to propel the widened segment 6. FIG. 2 shows a state in which the widened portion segment 6 has been advanced by seven rings from the state shown in FIG. The thrust transmitting member 8 is sequentially inserted in accordance with the advance of the widened face K, the shield M is dug by the propulsion jack 4, and the segment 6 is assembled in the widened portion. Reference numeral 7 in the drawing indicates a reinforcing member that connects the widened portion segment 6 and the thrust transmitting member 8 of the standard diameter portion. Hereinafter, the construction procedure will be described. First,
The ground improvement of the widened section, that is, the shelter installation part X performs ground improvement that can be opened, and the propulsion part Y performs ground improvement for water stoppage. Regarding the soil improvement method, a method suitable for soil quality will be used. Then, the standard diameter shield machine M excavates to a predetermined position in the widening section and stops. Of course, there is no need for ground improvement as long as the ground is self-supporting and does not require water pressure. Next, the standard segment 2 at the rear of the shield machine M, which is the starting point of the widening portion, is unframed and released, and the excavation is performed to install the shelter 3 on the outer periphery. Then, a widening propulsion facility such as a propulsion jack 4 is incorporated in the shelter. Excavation of the widened section face K in this way (manual excavation is also possible)
, The shield machine M is propelled by the propulsion jack 4, and the cutter of the shield machine is rotated while being linked to the propulsion amount, and the shield excavation is performed simultaneously. Then, it stops every time the excavating section segment width (for one ring) is excavated, incorporates the enlarging section segment 6 in the shelter section, propells the shield machine M and the enlarging section segment 6 again by the propulsion jack 4, and widens the excavation. Repeat until the end of the section. After passing through the widening section, the equipment such as the propulsion jack 4 is removed, and the operation returns to the normal standard diameter shield work. In addition, the shelter 3 installed in the widening section is buried and left. The present invention is configured as described above and has the following effects. (1) Widening work can be performed in the shield excavation process, and the process can be easily grasped. (2) Apart from widening propulsion equipment such as propulsion jacks,
The use of shield equipment for excavating the main unit is economical. (3) The excavation face of the widened part is less exposed, and the work safety is high. (4) The area for ground improvement can be reduced, and the cost can be reduced. (5) The standard diameter segment of the widened portion becomes unnecessary, and the cost is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing a state at a widening start position according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a state where several rings have been propelled from FIG. 1; FIG. 3 is a view for explaining a primary shield method of a conventional enlarged shield method. FIG. 4 is a view for explaining an assembled state of an enlarged shield according to a conventional enlarged shield method. FIG. 5 is a diagram illustrating a state of excavation of a widened portion by a conventional enlarged shield method. [Explanation of Signs] K: widened section face M: shield machine 2: standard segment 3: shelter 4: propulsion jack 6: widened section segment

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Akira Uesaka 1-2-7 Moto-Akasaka, Minato-ku, Tokyo Kashima Construction Co., Ltd. (72) Inventor Masayoshi Okamoto 1-2-Chome Moto-Akasaka, Minato-ku, Tokyo No. 7 Kashima Construction Co., Ltd. (72) Inventor Takashi Tsujii 1-2-7 Moto-Akasaka, Minato-ku, Tokyo Kashima Construction Co., Ltd. (72) Inventor Norio Mitani 2-chome Akasaka, Minato-ku, Tokyo No. 6 Inside Komatsu Manufacturing Co., Ltd. (72) Inventor Mitsuyuki Iwakiri 2-3-6 Akasaka Minato-ku, Tokyo Inside Komatsu Manufacturing Co., Ltd. (56) References JP-A-59-102086 (JP, A JP-A-59-102088 (JP, A) JP-A-59-102089 (JP, A) JP-A-60-30797 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) E21D 9/06

Claims (1)

(57) [Claim 1] A shield device for widening the cross section of a part of a section and excavating, comprising a shelter (3) installed at a place where the tail portion is widened and excavated with a tail portion as a starting point. In the shelter (3), a plurality of protruding jacks (4) for propelling the shield machine (M) and a widening section segment (6) are installed circumferentially at the end of the standard segment (2). Another propulsion jack (4a) used for propulsion of the widened segment (6) provided at the end is provided, and the widened segment (6) is provided in the shelter (3) by the propulsion of the shield machine (M). And a standard-diameter thrust transmitting member (8) is provided, and the widened portion segment (6) is provided.
A reinforcing member (7) for connecting the thrust transmitting member (8) and the thrust transmitting member (8).