JPH056472Y2 - - Google Patents

Description

[Detailed explanation of the invention] [Field of industrial application] This invention is applicable to steel pipes used in propulsion construction, such as water pipes, and especially as a composite pipe by combining the steel pipe with a concrete pipe formed around the steel pipe. It is related to the assembly structure.

[Prior Art] Fig. 5 is a structural diagram showing a conventional propulsion steel pipe, with Fig. 5a showing a side longitudinal sectional view and Fig. 5b showing a front sectional view. 6 is a cross-sectional view of the joint in FIG. 5, FIG. 6a is a cross-sectional view of the collar type joint, and FIG. 6b is a cross-sectional view of the segment type joint.

In the figure, 1 is a steel pipe, 2 is a cladding pipe formed on the outside of the steel pipe 1, and 3 is a filler filled in the gap between the steel pipe 1 and the cladding pipe 2. The filler 3 includes mortar and concrete. Commonly used. 4 is a steel pipe welded on site, 5 is a heat insulating material, 6 is a galvanized iron plate, 7 is a joint ring assembled and welded on site, 8 is a joint ring welded on site to weld the joint ring 7 and the cladding pipe 2, 9
10 is an exterior coating, 10 is an interior coating, 11 is an on-site exterior coating, 12 is an on-site interior coating, and 13 is a segment that is divided into a plurality of parts to be assembled on-site.

A conventional propulsion steel pipe assembly is constructed as described above, and the steel pipe 1 carries the load mainly by the propulsion force of, for example, a propulsion jack, and is propelled underground.

[Problems to be solved by the invention] The conventional propulsion steel pipe assembly as described above has the following problems.

(b) The mortar and concrete used as fillers only adhere to the steel pipe and cladding, and cannot serve as strong members, and the buckling resistance decreases as the diameter increases.

(b) The cladding and filler are used to protect the steel pipes, which increases the cost and is uneconomical.

(c) Since the only strength member is the steel pipe, the propulsive force can only be borne by the steel pipe, and the steel pipe is susceptible to buckling due to excessive propulsive force.

(d) During propulsion work, due to the low buckling resistance, the permissible range of bending left and right and up and down with respect to the propulsion direction is limited to small tolerances, and direction corrections must be carried out slowly. High construction precision is required.

(E) Since the joints of the joint type are not filled with mortar, their resistance to buckling is low, and the work is labor-intensive.

(f) Segment-type joints have low buckling resistance because the segments and steel pipes and cladding pipes are not integrated, and the work is labor-intensive.

This invention was devised to solve these problems, and the purpose is to obtain a propulsion steel pipe assembly that has increased resistance to buckling and has excellent workability.

[Means for Solving the Problems] The propulsion steel pipe assembly according to this invention consists of mesh reinforcement arranged in the steel pipe and concrete placed to cover the mesh reinforcement and the steel pipe. The above-mentioned problem is solved by providing a concrete pipe and a joint part provided through the concrete pipe end of the steel pipe connection part.

[Function] In this design, the concrete pipe becomes a composite pipe that is integrated with the steel pipe through the mesh reinforcement, and not only the steel pipe but also the concrete pipe absorbs the load caused by the propulsive force such as the propulsion jack at the joint. It is designed to be borne through the earth and propelled underground.

[Example] Hereinafter, an example of this invention will be described in detail with reference to the accompanying drawings. Note that the same reference numerals are used for the same parts as in the prior art described above.

FIG. 1 is a structural view showing a first embodiment of this invention, FIG. 1a is a side longitudinal sectional view, and FIG. 1b is a sectional view of a joint. In the figure, 20 is a steel pipe, 20a is a plurality of convex ribs provided in the outer circumferential direction of the steel pipe 20, 22 is a mesh bar welded on the rib 20a, and 24 is a mesh bar 2 excluding both ends.
2 and a concrete pipe made of concrete cast to cover the steel pipe 20; 26 a joint portion formed between the ends of the concrete pipe 24;
Reference numeral 26a denotes mortar mixed with an accelerating agent, which is filled after the steel pipes are welded on-site 4, and usually non-shrinkage mortar or resin mortar is used.

Next, the operation of the first embodiment will be explained. In the propulsion steel pipe assembly configured as described above, the rigidity of the steel pipe 20 is increased by the ribs 20a, and the concrete pipe 24 becomes a composite pipe that is integrated with the steel pipe 20 via the ribs 20a and mesh reinforcements 22. , not only the steel pipe 20 but also the concrete pipe 2 against loads caused by propulsion force such as propulsion jacks.
4 also bears the load through the mortar 26a filled in the joint part 26, and is propelled underground.

Therefore, due to sufficient adhesion performance between the steel pipe 20 and the concrete pipe 24, the steel pipe 20 and the concrete pipe 24 become integrated, which has the effect of improving resistance against buckling.

Furthermore, it is possible to reduce the thickness of the steel pipe 20, and economical effects such as eliminating the need to coat the outer surface of the steel pipe 20 due to the anticorrosive effect of the concrete layer can be obtained.

Furthermore, the joint part 26 has a simple structure,
Strength and workability. It has excellent water stopping properties.

FIG. 2 is a structural view showing a second embodiment of this invention, FIG. 2a is a side longitudinal sectional view, and FIG. 2b is a sectional view of the joint. In the figure, reference numeral 28 indicates a joint part with wider spacing than in the first embodiment, 28a indicates a joint reinforcing bar arranged through the exposed mesh bar 22, and 2
8b is concrete mixed with a rapid setting agent and an expanding agent, which is filled on site, and has the same effect as the first embodiment.

FIG. 3 is a structural diagram showing a third embodiment of this invention, FIG. 3a is a side longitudinal sectional view, and FIG. 3b is a sectional view of the joint part. In the figure, 30 is a joint formed by the concrete pipes 24 touching each other, 30a is a seal groove provided at the end of the concrete pipe 24, and 30b is a welded part provided at one end of the outer circumference of the steel pipe 20. The welding backing material 30b is a backing material, and the other end thereof is provided with a groove into which a part of the welding backing material 30b is accommodated. 30c is a sealing material having water-stopping performance attached to the sealing groove 30a, and has an effect equal to or greater than that of the first embodiment. That is,
If the sealing material 30c is attached in advance, there is no need to process the joint on site, and construction performance can be greatly improved. Also, the first embodiment and the second embodiment
It goes without saying that further effects can be achieved if the sealing material 30c is also used in the embodiment.

In the above embodiment, a plurality of convex ribs 20a are provided in the outer circumferential direction of the steel pipe 20, but even if the ribs are arranged as shown in FIG. 4, the same effect as in the above embodiment can be expected. I can do it. That is, FIG. 4 is a side view of a steel pipe provided with ribs, FIG. 4a is a side view of a steel pipe provided with ribs in a spiral shape, and FIG. 2 is a side view of a steel pipe that is
0b and 20c are ribs.

Furthermore, the concrete pipe in the above example is
It goes without saying that even greater effects can be expected if an RC structure or fiber-reinforced structure is used.

[Effects of the invention] As explained above, this invention becomes a composite pipe in which the concrete pipe is integrated with the steel pipe through the mesh reinforcement, so that it can withstand the load caused by the propulsive force of a propulsion jack, etc., not only the steel pipe but also the concrete pipe. Since the load is borne through the joint, the following effects can be obtained.

(a) As a composite pipe, it has high rigidity, has improved buckling resistance and bending strength, and can support applied loads across the entire cross section of the steel pipe and concrete pipe, allowing the steel pipe plate thickness to be reduced.

(b) Since the adhesion between the steel pipe and the concrete pipe is strengthened, economical effects such as eliminating the need for coating the cladding pipe and the outer surface of the steel pipe can be obtained.

(c) During propulsion work, up and down and
In addition to increasing the allowable range of left and right bends, the curvature can be reduced even when changing direction, etc.
Construction accuracy management becomes easier.

(d) The structure of the joint is simple, and as the joint ring type does not require a joint ring, there is no need for on-site welding work, and the segment type does not require segments, making it easier to assemble on-site. This makes it possible to improve the efficiency of on-site joint processing and reduce costs.

(e) The strength and water-stopping properties of the joint are improved.

[Brief explanation of the drawing]

FIG. 1 is a structural view showing a first embodiment of this invention, FIG. 1a is a side longitudinal sectional view, and FIG. 1b is a sectional view of a joint. Fig. 2 is a structural diagram showing a second embodiment of this invention, Fig. 2a is a side longitudinal sectional view;
Figure b is a sectional view of the joint. FIG. 3 is a structural diagram showing a third embodiment of this invention, FIG. 3a is a side longitudinal sectional view, and FIG. 3b is a sectional view of the joint part. FIG. 4 is a side view of a steel pipe provided with ribs, FIG. FIG. FIG. 5 is a structural diagram showing a conventional propulsion steel pipe, with FIG. 5a being a side longitudinal sectional view and FIG. 5b being a front sectional view. FIG. 6 is a cross-sectional view of the joint in FIG. 5, FIG. 6a is a cross-sectional view of the collar-type joint, and FIG. 6b is a cross-sectional view of the segment-type joint. In the figure, 20 is a steel pipe, 20a, 20b, 2
0c is a rib, 22 is a mesh reinforcement, 24 is a concrete pipe, 26, 28, 30 is a joint part, 26a is mortar, 28a is a joint reinforcing bar, 28b is concrete, 30a is a seal groove, 30b is a welded backing material, 3
0c is a sealing material. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. In a propulsion steel pipe assembly formed by connecting a plurality of propulsion steel pipes whose outer peripheral surfaces are covered with concrete pipes through joints, the outer peripheral surface of the main steel pipes is coated with a concrete pipe. A propulsion steel pipe characterized in that a convex rib is provided to restrain deformation and increase rigidity, mesh reinforcement is arranged in the concrete pipe, and the mesh reinforcement is fixed to the rib. assembly. 2. The propulsion steel pipe assembly according to claim 1, wherein the ribs are formed as a plurality of circumferential ribs continuous in the circumferential direction of the main steel pipe. 3. The propulsion steel pipe assembly according to claim 1, wherein the rib is formed as a spiral rib that spirally surrounds the outer peripheral surface of the main steel pipe. 4. The propulsion steel pipe assembly according to claim 1, wherein the ribs are formed as a plurality of axial ribs that are continuous in the axial direction of the main steel pipe. 5. The joint portion is embedded in an in-situ mortar layer filled between the pipe ends of each adjacent concrete pipe, extending from the mesh reinforcement in each of the adjacent concrete pipes and protruding into the mortar layer. 2. The propulsion steel pipe assembly according to claim 1, which is characterized by comprising exposed reinforcements. 6. The joint portion is embedded in a cast-in-place concrete layer filled between the pipe ends of each adjacent concrete pipe, and extends from the mesh reinforcement in each adjacent concrete pipe and protrudes into the concrete layer. The propulsion steel pipe assembly according to claim 1, which is a registered utility model, and includes exposed reinforcement bars arranged in the concrete layer to connect the exposed reinforcement bars. . 7. The propulsion steel pipe assembly according to claim 1, wherein the joint portion includes a contact surface between ends of adjacent concrete pipes. 8. The utility model registered in claim 1, wherein the joint portion includes a contact surface between the ends of adjacent concrete pipes, and a water stop seal interposed in this contact surface. Steel tube assembly for propulsion. 9 Utility model registration claim 8, wherein the joint portion includes a welded portion between the pipe ends of adjacent main body steel pipes, and a weld backing material disposed on the outer surface of this welded portion. Steel pipe assembly for propulsion described in .