JP3362961B2 - How to build large underground structures - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a large-scale underground skeleton in advance on the ground, and then digging the ground to set a caisson in the underground skeleton. And methods for constructing underground structures. 2. Description of the Related Art Conventionally, as shown in FIG. 4, a method of constructing an underground skeleton includes forming a caisson 2 having a cutting edge 4 on an outer peripheral portion of the skeleton on a ground 1 and working on a lower portion of the skeleton. The caisson 2 is sunk to a predetermined depth while excavating the ground in the space 3 and excavating the excavated earth and sand by carrying out means such as a grab bucket. [0003] However, in the above-described construction method, when the length of the caisson 2 is small, the laying operation can be performed relatively easily. If the caisson is a large caisson of 25m or more, reinforcement work is required to prevent distortion of the frame, the construction period is lengthened, and the reinforcement work takes time and costs increase There was a problem. As described above, in order to construct an underground skeleton by laying down a conventional large-scale caisson, reinforcement of the underground skeleton is required, and there is a problem to be solved in terms of construction period and cost. The present invention has been made in view of the above problems, and an object of the present invention is to provide a construction method for shortening a construction period, facilitating construction, and reducing costs. The gist of the present invention to solve the above-mentioned problems and achieve the above-mentioned object is to provide a large-scale underground skeleton on the ground and a cutting edge for laying under the underground skeleton. In a construction method of protruding and constructing a caisson in advance, excavating the ground in the working space formed by the cutting edge, and sinking the underground skeleton, a cutting edge is provided on an outer peripheral portion of a lower portion of the underground skeleton, and the underground skeleton is provided. Also supports the middle part inside the lower part of
The inner edge of providing, construct each floor of the caisson
When the long span in the part without the wall when the
A removable temporary reinforcing wall is provided on the internal
The underground skeleton is sunk on the ground while preventing the distortion of the skeletal structure and firmly maintained, and after the sunk, the temporary reinforcing wall is removed.
This is the construction method of the large underground skeleton to be removed. According to the present invention, when a large-scale caisson is constructed and submerged in the ground, the caisson is provided on the lower surface of the lower part of the underground skeleton and on the inside of the cutting edge provided on the outer peripheral portion of the skeleton. By providing a double-edged cutting edge, the middle part of a large underground skeleton is supported, and even a long span underground skeleton can be laid without special reinforcement work. Can be. [0008] If a pulling means for sinking is provided in the vicinity of the inner cutting edge provided on the inner side, or if a temporary reinforcing wall is provided on the inner cutting edge, a large scale is provided. Can be laid down evenly underground,
The temporary reinforcing walls also prevent distortion of the underground skeleton and improve the efficiency of the laying operation. Next, an embodiment according to the present invention will be described in detail with reference to the drawings. Parts corresponding to those in the conventional example are denoted by the same reference numerals for easy understanding. In the method for constructing a large-scale underground skeleton according to the present invention, a caisson 2 of the underground skeleton is previously constructed on the ground 1 as shown in FIG. The caisson 2 is formed by providing a cutting edge 4 at an outer peripheral portion of a lower portion of a frame, and further providing an inner cutting edge 4a inside a lower portion. When constructing each floor of the caisson 2, as shown in FIG. 2, when the central portion of the skeleton is a core portion 2 a such as an elevator or a stair, a wall is provided. As shown in FIG. 3, a temporary reinforcing wall 2c in which a PC plate or the like is detachable with bolts or the like is provided in a portion having no long wall and having a long span. Further, as shown in FIG. 1 (b), while controlling the large-scale caisson 2 by a control device or the like (not shown), the entire frame is uniformly sunk to prevent uneven settlement. The required number of ground anchors 5 will be provided. The ground anchor 5 is provided near the internal cutting edge 4a in order to avoid deformation of the beam due to a reaction force. The tension means for pulling the ground anchor 5 and submerging the underground skeleton 2 by the reaction force is, for example, a center hole type hydraulic jack 6 provided at the end of the anchor. Thus, the caisson 2 for the underground skeleton
Is constructed in advance on the ground, excavation work is performed in the work space 3 to remove earth and sand from the ground, and the ground anchor 5 is evenly pulled under automatic control by the hydraulic jack 6,
The underground skeleton 2 is laid down to a predetermined depth. The caisson 2 includes the internal cutting edge 4a,
The temporary reinforcing walls 2c prevent the body from being distorted and are sunk while maintaining the body firmly. After the caisson 2 is laid down,
The temporary reinforcing wall 2c is removed by removing bolts and the like. As described above, the method for constructing a large-scale underground skeleton according to the present invention provides a method for constructing a large-scale underground skeleton on the ground and projecting a cutting edge under the underground skeleton. Beforehand
In the construction method of constructing a substructure, excavating the ground in the working space formed by the cutting edge, and laying down the underground skeleton, a cutting edge is provided on the outer peripheral portion of the lower portion of the underground skeleton, and the inside of the lower portion of the underground skeleton is provided. Also provided an internal cutting edge to support the middle part, when building each caisson floor
In the part where there is no wall and the span becomes long, the internal blade
A removable temporary reinforcing wall is provided on the tip to
While preventing distortion and maintaining strong, the underground skeleton is sunk on the ground, and after the sunk, the temporary reinforcing wall is removed, so that a large-scale underground skeletal construction method is adopted. The double-edged cutting edge prevents the occurrence of distortion in the underground skeleton with a long span, allows the large-scale underground skeleton to be laid down, and eliminates the construction work such as reinforcement work to prevent the occurrence of the distortion, thereby reducing costs. It has an excellent effect that reduction and shortening of the construction period can be achieved. When the floor of the caisson is constructed, a wall is provided on the inner cutting edge supporting the intermediate portion.
A temporary reinforcement wall that can be attached and detached is provided at the part that has a long span, so that not only can a large-scale underground structure be laid down uniformly on the ground, It can be sunk with high stability only by reinforcing part of it, and it has an excellent effect of improving the reliability and safety of siding work.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram (a) and (b) showing a method of constructing a caisson of an underground skeleton in advance on the ground according to the method of constructing a large-scale underground skeleton according to the present invention. is there. FIG. 2 is a plan view of the underground skeleton. FIG. 3 is a longitudinal sectional view showing a state in which the large-scale caisson is sunk on the ground. FIG. 4 is an explanatory view showing a method of constructing an underground skeleton by laying a caisson according to a conventional example. [Description of Signs] 1 Ground, 2 Caisson, 2c Temporary Reinforcement Wall, 3 Work Space, 4 Cutting Edge, 4a Internal Cutting Edge, 5 Ground Anchor, 6 Hydraulic Jack.

Continuation of the front page (56) References JP-A-3-217520 (JP, A) JP-B-39-27429 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) E02D 23 / 08 E02D 23/00

Claims (1)

(57) [Claims 1] A caisson is constructed in advance by constructing a caisson by setting a large underground skeleton on the ground and projecting a cutting edge at the bottom of the underground skeleton, and forming the caisson in advance. In the construction method of excavating the ground in the working space and sinking the underground skeleton, a cutting edge is provided on an outer peripheral portion of a lower portion of the underground skeleton, and an inner cutting edge for supporting an intermediate portion is also provided inside a lower portion of the underground skeleton,
Parts without walls when building each caisson floor
On the internal cutting edge at the part where the span is long
A flexible temporary reinforcing wall is provided to prevent distortion of the underground skeleton.
While firmly maintaining , submerged the underground skeleton on the ground ,
A method for constructing a large-scale underground skeleton , comprising removing the temporary reinforcing wall after the submerged construction.