JPS6015763B2 - How to erect a concrete arch structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for constructing a concrete arch structure such as a concrete arch bridge.

Generally, when constructing a concrete arch bridge, it is difficult to provide support from the ground over the entire length of the arch bridge, so as shown in Fig. The Meran method involves constructing a cantilever by spanning the steel materials) 2 and wrapping the Meran steel materials 2 using Wagen 3, etc., or by erecting temporary supports (pilons) 5 on the piers 4 of the arch support surface 1, as shown in Fig. 2. A pilon method is adopted in which cantilever construction is carried out while the arch rib 7 is suspended obliquely from the pilon 5 using cables 6, 6, . . . .

However, since the conventional Meran method involves assembling steel shoring to form an arch-shaped shoring, it is necessary to cast arch rib concrete, pedestal concrete, and upper deck concrete to obtain the desired design load capacity. Meran steel has a high steel weight to ensure safety against the concrete's own weight and bending moments and buckling caused by wind and earthquakes during erection, and it is not useful at all as an erection material. .

Furthermore, even with the pilon method, since the arch lip is extended in a one-sided state, stability against strong winds and vibrations is poor during the construction of the arch rib.

In view of the problems of conventional construction methods as described above, the present invention aims to provide a method for constructing a concrete arch structure that has good seismic and wind resistance stability during arch rib construction, is low in construction cost, and is easy to manage. The gist of this is that a plurality of hollow cylindrical arch-shaped supporting steel members are supported at both ends on the support surface of the arch structure to be constructed, and are placed in parallel to each other. are connected to each other using connecting materials as appropriate, and then concrete is filled into the hollow interior of the supporting steel material, and then, with the supporting steel material as the core, externally wrapped concrete is sequentially cast from both ends of the supporting steel material toward the top. The method of constructing a concrete arch structure is characterized by:

Next, based on the embodiments of the present invention shown in the drawings from FIG.
This will be explained in more detail.

First, support surfaces (archbutts) 10, 10 for supporting the concrete arch structure to be constructed are constructed using a conventional method.

Both ends of the supporting surfaces 10 and 1 are supported by pins, and arch-shaped supporting steel members 11, 11, . . . are bridged in a parallel arrangement to each other. As shown in FIG. 7, this supporting steel material 11 is made of a steel plate and has a fixed length unit 12, 12, which is formed into a rectangular tube shape.
... are connected to each other by bolts or welding via the attachment plate 13, and are bridged. Further, each unit 12 is reinforced with vertical and horizontal stiffeners 12a, 12a, . . . as necessary on its upper and lower surfaces and both side surfaces. In addition, when constructing this support steel 11, each unit 12, 12...
- was transported to the erection position by cable crane 14 and connected to the previously connected unit 12, followed by diagonal suspension wire -15.
It is supported by a single standby structure, and is constructed by extending successively from both supporting surfaces 10, 10 to the central portion.

In addition, as shown in FIG. 8, the half-supported steel members 16a, 16a, in which the unit 12 is assembled to half the total length, are held at their respective ends against the support surface 10, and can be freely rotated using pins 17, 17. In addition to the above, although not shown in the figure, the supporting steel 11, which has been preassembled over its entire length, may be supported by a floating crane or a truck crane. It may also be erected using a crane such as In this way, a plurality of supporting steel members 11, 11...
After spanning, the supporting steel members 11, 11... are laterally connected using connecting members such as struts 18 and laterals 19.

After that, concrete 20 is poured into the hollow interior of each of the supporting steel members 11, 11, . . . .

This concrete 20 is placed in advance by supporting steel 11.
Concrete is poured into each supporting steel material 11, 11, etc. simultaneously and symmetrically and sequentially from both ends toward the center. This forms a composite arch support consisting of a steel box and concrete. After the concrete 20 cast in this manner hardens, outer concrete 21 (shown in Figures 9 and 10) is poured around the composite supporting steel materials 11, 11, etc. as a core to form a concrete arch structure. complete something.

When pouring this outer concrete 21, as shown in FIG. 9, a movable suspension frame 22 similar to the conventional one is used, and a formwork 23 is suspended from this to form the supporting steel 11 into the desired cross-sectional shape. It is formed sequentially from both ends toward the center. Note that connecting reinforcing bars are arranged between the outer concrete 21 and the supporting surfaces 10, 10, and the outer concrete 21 is cast integrally with the supporting surfaces 10, 10 to form a rigid connection between the two. The present invention is constructed as described above, uses a hollow cylindrical support steel material, fills the hollow inside with concrete, and uses this as a core and casts an outer wrap around the concrete, thereby preventing buckling. This creates a shoring that does not easily cause damage and is highly stable against vibrations and wind, and can withstand high loads on its own.For example, when used as an arch rib on a concrete arch bridge, the shoring works reduce the supplementary load of the entire arch bridge. It is economical because there is no wastage of materials as the cost can be covered by a part of the cost.

In addition, since the supporting steel material is hollow and cylindrical, it is lightweight and easy to erect.Furthermore, the shoring material can withstand high loads simply by pouring concrete into the interior after the erecting. It has various advantages such as requiring less temporary equipment, significantly improving work efficiency, and facilitating construction management, and its effects are enormous.

[Brief explanation of the drawing]

Figure 1 is a side view showing the conventional Meran method of construction;
Figure 2 is a side view showing the construction method using the conventional pilon method;
Figure 3 and the following drawings show embodiments of the present invention.
The figure is a side view of the supporting steel in the installed state, Figure 4 is a plan view of the same,
Figure 5 is a cross-sectional view of concrete poured into the supporting steel after erection, Figure 6 is a side view of an example of how to erect the supporting steel, Figure 7 is an enlarged side view of the supporting steel, and Figure 8 is an enlarged side view of the supporting steel. FIG. 9 is a side view of another method of constructing steel materials, FIG. 9 is a side view of the outer concrete being placed, and FIG. 10 is a sectional view after the concrete is placed. 10...Supporting surface, 11...Support steel, 18...
...Strut (connecting material), 19...Horizontal groove (connecting material), 20...Concrete, 21...
・Outer wrapping concrete. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 9 Figure 8 Figure 10

Claims (1)

[Claims] 1. After installing a plurality of hollow cylindrical arch-shaped supporting steel members in parallel arrangement, with both ends supported on the supporting surface of the arch structure to be constructed, and connecting the supporting steel members to each other using connecting materials as appropriate. A concrete arch structure characterized by filling the hollow interior of the supporting steel with concrete, and then sequentially pouring concrete around the supporting steel as a core from both ends of the supporting steel toward the top. construction method.