JP2831568B2 - Segments made of glulam and beams - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a segment for constructing a tunnel by a shield method such as a subway, electric power, telegraph and telephone, and a common ditch.

[0002]

2. Description of the Related Art For a long time, materials such as wood, cast iron, steel, concrete and the like have been used as materials for a segment, and various studies have been made on strength problems, economic problems or construction problems. Has been made.

[0003]

Although each material segment has its advantages and disadvantages, the wood segment has the advantages of being lightweight, easy to handle, and capable of being constructed by human power, but is weak against buckling in the vertical axis direction and exerts thrust. It is difficult to apply to construction methods that must be performed. Cast iron segments are expensive to manufacture,
It is heavy and requires heavy equipment to handle, making construction difficult. The steel segment has high rigidity against earth pressure and a small cross section, but has a disadvantage that it is weak against deformation in the longitudinal direction. Also, the concrete segment had to go through a process of assembling a curved high-precision formwork at the time of manufacturing, incorporating a reinforcing bar inside and casting concrete, and a great deal of labor was required for assembling and removing the formwork. In addition, there is a drawback that the weight is heavy and handling is troublesome. In recent years, however, glued laminated timber has been in the limelight with sawing several logs with a saw, applying heat and drying, applying a crack adhesive, and stacking, compressing and solidifying. Glued lumber has the same specific gravity as ordinary wood, has much higher strength than wood, and can be molded freely. In view of this, there has been invented a structure in which the segments are made of glued laminated lumber, which has a higher proof strength than wood, making use of the light weight of wood. In order to further improve this and increase the strength,
A steel beam is embedded in the glulam to provide a lighter yet stronger segment.

[0004]

The segment is formed by dividing the circumference of a cylindrical cylinder having a substantially thickness into several equal parts, and is divided into several blocks along the circumference so that the beam can be included in the laminated wood. The glued block is glued by enclosing several beams that pass in the circumferential direction, and the ends of the beams are formed with flanges to join the segments together, and are exposed at the ends of the segments. The beam is either buried in the glued lumber or buried in a position slightly retracted from the end of the segment. And,
A hole for bolt penetration is formed in the flange, and a part where the glued wood is cut out is provided behind the flange, and the segments are joined by bolts to form a ring. When joining in the axial direction, a long bolt hole in the axial direction is opened in the segment and fastened with a long bolt. For circumferential joining, it is also possible to integrate the segments in a ring shape with a wire that goes around the ring without using a bolt.

[0005]

The segment of the present invention is lighter in weight than the segment made of only wood or laminated wood, has higher strength than the segment made of only wood or laminated wood, and is much easier to handle than segments made of concrete, cast iron, steel and the like. In particular, the present invention is free from troublesome molds and casting operations as in the cast iron segment, without the trouble of assembling and removing the formwork as in the concrete segment.

[0006]

FIG. 1 shows an embodiment of the present invention. (A) is a top view and (b) is an AA cross-sectional view. FIG. 2 is a diagram in which two H-shaped beams 2 are included and adhered to a laminated wood 1 in which a segment is divided into three in the circumferential direction. FIG. 1B shows a long bolt 3 for fastening the segment in the axial direction and a cutout 5 behind the beam flange 4 for fastening the segment in the circumferential direction. FIG. 2 shows a BB cross section of FIG. FIG. 3 shows an example in which the beam flange 4 is provided at a position slightly retreated from the end of the segment. In this example, the beam 2 is made of flat steel of H
Although what is welded to the mold is used, it is of course possible to use a round bar beam.

[0007]

The effects of the present invention are as follows.

(A) Unlike the concrete segment, the complicated labor of assembling and removing the formwork is not required at the time of manufacturing.

(B) Rigidity and strength are superior to segments made of only wood or laminated wood.

(C) The use of glued laminated timbers and beams makes it lightweight and easy to handle.

[Brief description of the drawings]

FIG. 1A is a top view of an example of the present invention. (B) It is AA sectional drawing of (a).

FIG. 2 is a sectional view taken along line BB of FIG. 1 (b).

FIG. 3 is a diagram of an example in which a beam flange is provided slightly backward from an end of a segment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Glued block, 2 ... Beam, 3 ... Long bolt, 4 ... Beam flange, 5 ... Notch

Claims (1)

(57) [Claims] 1. A segment is formed by dividing the circumference of a cylindrical cylinder having a thickness into equal parts, and is divided into several blocks along the circumference so that a beam can be included in the laminated wood, and a block is formed. The block of glued lumber includes several beams that pass in the circumferential direction and is glued. The ends of the beams are formed with flanges to join the segments together, and the beams are assembled to be exposed at the ends of the segments. A segment comprising a laminated wood and a beam, wherein the segment is buried in the material or buried at a position slightly retreated from the end of the segment, and a notch for bolt fastening is provided behind the flange.