JP3417865B2 - Method of constructing structure using strut and strut structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a heavy object while temporarily supporting it with a pillar (vent) and a pillar used for the method. More specifically, for example, construction of a cast-in-place concrete bridge or the like. The present invention relates to a method and a structure of columns used for supporting the method.

[0002]

2. Description of the Related Art In the case of constructing or assembling a heavy object at a high place, it is common to erect a pillar to temporarily support the structure and to remove the pillar after the structure is completely assembled.

In an elevated road bridge to be cast-in-place, there is a technique of completely assembling the support work in the space under the bridge with frame scaffolds and the like, and assembling the formwork on it. This is inconvenient when a road is required or when the valley is deep. In this case, instead of assembling the support work on the entire surface, columns are erected at appropriate intervals in the span direction, support beams such as H-shaped steel are erected between the columns, and the formwork is assembled on it. Technology is adopted.

FIG. 11 shows an example of construction of a bridge using such columns. Pillar foundation concrete 33 is placed between the abutments 31 and piers 32 at equal intervals, and temporary braces 35 are erected on the pillar foundation concrete 33, and the support girders 36 are erected on these pillars. The formwork is assembled and the bridge 37 is constructed in the formwork with cast-in-place concrete. FIG. 11 shows a temporary road 34 for construction.

FIG. 12 is a sectional view taken along line GG of FIG. 11. In this case, since it is necessary to support the weight of the bridge 37 by a small number of temporary columns 35, a temporary column formed by combining a large diameter steel pipe or the like. 35 is used.

Further, FIG. 13 shows an example of a bridge laid in a narrow valley. This is an example in which a part of both banks is made a post-construction part 41 and then construction is carried out by using support work, and the portion above the water surface 44 of the deep valley in the center is overlaid. The weight of the overhanging bridge body 43 and the overhanging and erection device 42 in the central overhanging and supporting portion is supported by the temporary strut 35 to support the overhanging bridge body 4.
3 is constructed and the centers of the overhanging bridge bodies 43 extending from the left and right are connected. After that, the temporary columns 35 are removed, and then the post-construction portions 41 on both banks are constructed and completed.

The temporary columns used for these construction work are
Based on Euler's formula, Young's modulus, Poisson's ratio, and other parameters, calculate the cross-section required for the length and the shrinkage strain due to the load, and build up the structure at a predetermined height position. Is calculated and used. In this case, it is necessary to cumulatively consider the dead amount that is difficult to predict, such as the die steel to be mounted, the form plate, and the gap between the connecting surfaces between the columns. It was

[0008]

SUMMARY OF THE INVENTION In the present invention, in a method of constructing a structure to be constructed while temporarily supporting it by a column, a part of the elements for calculating the amount of overlift is calculated and analyzed beforehand. An object of the present invention is to provide a method for constructing a structure which is constructed while maintaining the structure under construction at a height position of a more accurate setting, and a pillar structure used for the method.

[0009]

The present invention was developed in order to solve the above problems, and its technical means is equivalent to the total weight of a load in a method of constructing a structure that is constructed while temporarily supporting it with a support column. A structure for using a strut characterized in that an axial compressive force to be applied to the strut in advance is released, and the axial compressive force applied to the strut is released stepwise as the structure construction process progresses. It is a construction method.

Here, the total weight to be loaded refers to the weight that each column should support in the process of constructing a structure such as a top-mounted steel material, a formwork material, concrete and rebar forming a structure. When the columns are equidistant, the total weight is obtained by dividing the total weight of the columns by the number of columns to be supported, but the value varies from column to column depending on the arrangement and position of the columns.

The columns used in the above construction method are the structures under construction.
In a strut that temporarily supports a structure, joins both ends of the strut as a mechanism that applies an axial compressive force equivalent to the total weight of the load.
Introducing axial compression force into a large number of PC steel materials
And further comprising a jack device or to or released
It is a pillar structure. Also, this post is fabricated to comprise one or a plurality of steel pipes, Ru easy handling suitable der.

[0012]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described below with reference to the drawings.

FIG. 1 is a side view showing an example of a steel pipe support (vent) 1 used in the form shown in FIG.
1 is an AA arrow view of FIG. 1, FIG. 3 is a BB arrow view of FIG. 1, FIG. 4 is a CC arrow view of FIG. 1, and FIG. 5 is a DD arrow view of FIG. Is. As shown in FIG. 3, two steel pipes 2 are connected in parallel to each other by a horizontal tie member 10 and a flange 4, and saddle steel members 3 are attached. This configuration is adopted. As shown in FIGS. 1 and 2, at the upper and lower ends thereof, two Ps are attached per surface through the loading beam 5.
C steel rod 6 is attached. Tension transmission beams 7 are arranged vertically at an intermediate position to connect the PC steel materials 6 to each other. A hollow hydraulic jack 8 is provided on the tension transmission beam 7 thereabove. That is, the hollow hydraulic jack 8 is attached to the upper tension transmission beam, and the tension rod 9 is connected to the tip of the ram 11 and the lower tension transmission beam 7. The hollow type hydraulic jack 8 can uniformly introduce the axial compressive force to the steel pipe 2 through the PC steel rod 6 by extending the ram 11.

The tension force applied to the hollow hydraulic jack 8 is a tension force corresponding to the load produced by the total weight of the load acting on the column 1, and the contraction strain deformation assumed to be caused by the total weight of the column is preliminarily applied to the column. It is for giving to.

6 to 8 show examples of other columns.
6 is a side view, FIG. 7 is a view taken along the line EE of FIG. 6, and FIG. 8 is FIG.
It is a FF arrow line view of. This support column 1 is an example of a support column 1 for heavy load of several hundred tons, which is suitable for use in the form as shown in FIG. 500-1000m in this example
A large-diameter steel pipe 2 having a diameter of about m is used. A plurality of PCs, each of which has a loading frame 13 including a hollow hydraulic jack 8 mounted on the upper portion of the steel pipe 2 and vertically penetrates the steel pipe 2,
This is a column 1 in which steel rods 6 or PC strands are arranged to uniformly apply shrinkage strain. In this case, the PC steel rods 6 may be arranged around the steel pipe 2 instead of inside the steel pipe 2.

In this way, the column 1 is preliminarily applied with the axial compressive force.
Exclude from the calculation of the amount of overhang before the construction because the column that has been given a contraction strain in the longitudinal direction of the column does not change (increase) the strain amount after the loading load acts can do. This contraction strain suppresses a change in the contraction strain by gradually releasing a pre-applied axial compressive force corresponding to the load of the structure acting on the support column stepwise as the construction process progresses. The release of this load is performed by monitoring the load meter of an electric hydraulic pump (not shown) that operates the hollow hydraulic jack 8 and operating the hydraulic jack to release the axial compression force. As a result, the set height position can always be maintained at a substantially constant height, and the structure can be constructed at a more accurate height position.

FIG. 9 is an explanatory view showing the concept of the behavior of the pillar of the present invention. 10A and 10B are conceptual diagrams showing the behavior of a conventional type of column. FIG. 10A is a state of the column 22 before the top load 21 is loaded, and FIG. 10B is a column 23 after the top load 21 is loaded. Shows the state of. The height H set on the column 22 before the top load 21 is loaded is reduced by the contraction strain Δh at the column 23 after the top load 21 is loaded. Figure 9
In the present invention shown in FIG. 9A, as shown in FIG. 9A, an axial compressive force 24 equivalent to the overload is applied in advance to cause distortion before the overload is loaded, and FIGS. As the process progresses and the top load 21 increases, the corresponding axial compression force 24 is released as shown in FIG. Eventually,
As shown in FIG. 9 (d), all the axial compressive force generated in the column 1 is replaced by the overlaid load 21, and the contraction strain of the column 1 does not increase or decrease from the beginning to the end of the building process.

For these columns (vents) 1, a plurality of bent blocks having a single length are connected and used. The compressive force may be applied to each vent block of a single length, but if the compressive force is applied over the entire length after assembling a plurality of blocks to a length matched to a predetermined height, each vent block connecting surface This is convenient because the dead amount of can be excluded.

In the above embodiments, an example in which a cylindrical steel pipe is used as the main material of the supporting column has been shown, but the present invention is not limited to this, and a rectangular steel pipe can be similarly used.
Alternatively, it is needless to say that H-shaped steel, I-beam, and other shaped steels can also be applied by devising the arrangement method of the PC steel material.

When the strut structure of the present invention shown in FIGS. 1 to 6 is applied to a structure as shown in FIGS. 11 and 13, the strut is removed after the structure (bridge) is completed. Is
Although not shown, a known method such as inserting a jack at the upper end or the lower end of the column and reducing the jack to remove it may be used.

[0021]

According to the present invention, in a column for temporarily supporting a structure under construction, an axial compressive force corresponding to the total weight of loading causing an expected strain is applied to the column in advance, and the process proceeds. By releasing the axial compressive force in accordance with the overloaded load that increases as a result, the height of the column can be kept constant. Therefore, the column portion can be excluded from the numerical value of the amount of lifting and the accurate height position can be set. In addition, it is preferable that the support column is made of one or a plurality of steel pipes because it is easy to manufacture and handle. In addition, the axial compressive force is the same as PC steel rods, PC strands and other PCs.
It is convenient to apply it by steel material. By using the support column that does not change (increase) the contraction strain, complicated calculation for raising can be simplified, and the effect of contributing to more accurate construction is great.

[Brief description of drawings]

FIG. 1 is a side view of a pillar of an embodiment.

FIG. 2 is a view on arrow AA of FIG.

FIG. 3 is a view taken along the line BB of FIG.

FIG. 4 is a view taken along the line C-C in FIG.

FIG. 5 is a view on arrow D-D of FIG. 3.

FIG. 6 is a side view of a column of another embodiment.

FIG. 7 is a view on arrow EE in FIG.

FIG. 8 is a view on arrow FF in FIG.

FIG. 9 is a conceptual diagram showing the behavior of the pillar of the present invention.

FIG. 10 is a conceptual diagram showing the behavior of a conventional strut.

FIG. 11 is a side view showing an example of a structure to which the present invention is applied.

FIG. 12 is a view taken along the line GG in FIG.

FIG. 13 is a side view showing another example of a structure to which the present invention is applied.

[Explanation of symbols]

1 prop (vent) 2 steel pipe 3 saddle steel 4 flange 5 loading beams 6 PC steel rod 7 Tension transmission beam 8 hydraulic jack 9 Tension rod 10 Horizontal ties 11 Ram 12 pedestal concrete 13 loading frame 14 Mounted structure 21 Loaded amount 22 Support before loading 23 Posts after loading 24 Axial compression force 31 abutment 32 piers 33 pillar foundation 34 Temporary road 35 Temporary columns 36 support girder 37 Bridge 41 Post-construction part 42 Overhanging equipment 43 Overhang bridge 44 Water surface

Claims (3)

(57) [Claims] 1. A method of constructing a structure which is constructed while temporarily supporting it with a support column, wherein an axial compressive force corresponding to the total weight of the load is applied to the support column in advance, and a stepwise process is carried out as the structure construction process progresses. A method for constructing a structure using a pillar, wherein the axial compression force applied to the pillar is released. 2. A support for temporarily supporting a structure being constructed, and a mechanism for applying an axial compressive force corresponding to the total weight of the load.
And a large number of PC steel materials for connecting between both ends of the pillar and the P
Jack for introducing and releasing axial compression force on C steel
A strut structure characterized by having a device . 3. The strut structure according to claim 2, wherein the strut is composed of one or a plurality of steel pipes.