JP3037912B2 - Power transmission tower foundation construction method and pillar formwork - 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 power transmission tower foundation, which is a foundation for building a power transmission tower, and a column formwork used for the method.

[0002]

Conventionally, the construction of a power transmission tower foundation has been carried out by arranging a base bar at the excavated bottom of the ground to be formed of the power transmission tower foundation excavated in the area to be constructed, and driving the base concrete. After constructing the part, set the column formwork made of FRP or steel plate formed in the outer shape of the base body on the base, put the ready-mixed concrete from the top end of the formwork, solidify and cure the formwork It was done by removing, collecting and backfilling.

However, since the base portion and the base body column are separately cast in concrete, there is a possibility that impurities may be mixed into a joint portion between the base and the base body column, and the design strength is surely ensured. There is a problem that cannot be expected.

[0004] In addition, the setting work is dangerous because the column form is set in an unstable state. On the other hand, in the case of the FRP or steel sheet form, since the form is bulky and difficult to move, it is difficult to set the column form. Required skill and a great deal of labor.

In addition, since ready-mixed concrete is directly introduced from the top end, the concrete has been constructed without any means for checking whether the design concrete strength is secured and whether the aggregate and the cement are not separated. I have.

Further, since the form of FRP is inferior in strength, it cannot be used when the height of the column of the base body is high, and the form made of steel plate is heavy and requires storage maintenance during construction. Although it was difficult to handle above, there is an advantage that it can be used many times with ready-made forms, but it is impossible to prepare molds of all dimensions and shapes according to the construction conditions of the power transmission tower foundation Therefore, it is more reasonable to design each formwork each time.

[0007]

SUMMARY OF THE INVENTION In accordance with the present invention, there is provided a transmission tower having a base member, a column bar and a base bar disposed on an excavated bottom of a ground to be constructed. Install a column base formwork in which the basket frame constructed in the base shape is lining with a mesh panel, cast base concrete, and place the top structure of the power transmission tower base on the top of the column base form. The upper frame of the pillar body, which was constructed by covering the basket frame with the mesh panel, was placed and set, and the ready-mixed concrete was poured into the pillar frame,
It is made to be buried as it is.

In other words, by simultaneously casting the base portion and the base portion of the base body column portion with concrete, the base portion and the column body base portion are integrally formed, thereby avoiding the joint structure and stabilizing the column portion type. This makes it possible to set a frame.

[0009] Further, by forming the structure of the column body frame by covering a basket frame having a basic shape with a net panel, the weight of the column body frame can be reduced, and the state of concrete filling can be visually checked from the outside. I did it.

Further, the column form is divided into units to form a unit shape, and a window hole for injecting ready-mixed concrete is provided on the side wall of the unit as appropriate, thereby facilitating the handling and injecting the ready-mixed concrete stepwise. I was able to do.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. Reference numeral 1 denotes an excavated portion for excavating a transmission tower foundation body formation area. First, a columnar bar and a base bar 23 formed by a combination of a base member 2 made of an angle steel material or the like, a main bar 21 and a hoop bar 22 at the bottom thereof. Is disposed, a columnar formwork 3 which is a cylindrical base is set around the periphery thereof, and a base concrete 11 is cast to integrally form the base portion S and the columnar base portion.

The base portion S is constructed by assembling a metal frame for preventing blow-up and a steel net, and in some cases, simultaneously using the reinforcing base cover frame fixing metal to simultaneously cast concrete with the column base portion smoothly. To do.

When the formation of the base portion and the column base portion is completed, the column upper form 3B is placed on the column base form 3A, and the anchor or liner plate hole 12 set on the wall surface of the excavation portion 1 is set. With a fixed point as a tension material such as a chain or wire
After fixing the position by 13, the upper end hoop frame 31 of the base formwork 3A and the lower end hoop frame 32 of the upper formwork 3B are fastened by a number line 42 and the required parts are welded 41 to fix the position. Reference numeral 4 denotes a working scaffold.

When the position of the upper mold 3B is fixed, the upper mold 3C is further placed on the upper mold 3B to perform the same fixing work, and the same steps are repeated to sequentially load the upper molds. Form the pillar formwork to the surface.

The column body frame 3 includes hoop streaks 33, 33,... Arranged at appropriate intervals between an upper hoop frame 31 and a lower hoop frame 32.
..Combined with vertical reinforcing bars 34, 34,..., And if necessary, a single pipe 35 is added to the outside to form a basket frame 30 and the inside is wrapped with a mesh panel 36. To form a cylindrical shape.

If the diameter of the column form is large or the sectional shape of the column form is special, the column form is divided into vertically divided units, and the cage frame 30 is formed into a curved plate shape. The column bars at the left and right ends of the vertically divided units 3a and 3b are fastened together by a number line 42, and required parts are welded 41 to form a cylindrical shape. The work of forming the cylindrical shape may be performed on site or at a design factory.

Further, a window hole 5 configured to be openable and closable on a side wall is set in the column form 3 loaded at a predetermined position, and steps are sequentially set from the window holes set below the formed column form. It is designed to inject and mix ready-mixed concrete.

When the formation of the column form to the surface of the ground by the loading of the column form 3 is completed, the ready-mixed concrete is sequentially and stepwisely arranged according to the height from the window hole set at the lower portion of the formed whole form. To form a base body 6 while preventing separation of aggregate and cement from ready-mixed concrete.

In this case, it is possible to visually check the state of injecting and filling of the ready-mixed concrete from the outside through the mesh panel 36. Therefore, it is necessary to check whether the design concrete strength is secured and whether the aggregate and the cement are separated. Can be.

After the foundation column 6 is formed, the excavated portion 1 is back-filled with the required back-filling material T to complete the construction of the power transmission tower foundation.

[0021]

[Brief description of the drawings]

FIG. 1 is an overall side view showing the construction of a transmission tower foundation according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA in FIG. 1 showing the column bars, the base bars, and the column frame being set up in the excavated portion with the leg material as the center.

FIG. 3 is an overall side view of a cross section of the base portion showing a situation in which a column base formwork is also erected at the bottom of the excavated portion and base concrete is poured.

FIG. 4 is an enlarged side view of the unit joint, also showing the connection state of the column form units by the upper and lower horizontal split units.

FIG. 5 is a partial cross-sectional view taken along line BB of FIG. 4;

FIG. 6 is an enlarged side view of the unit joint, showing the connection state of the column form unit by the vertically divided unit.

FIG. 7 is a partial cross-sectional view taken along the line CC of FIG. 4;

FIG. 8 is a longitudinal sectional side view showing the structure of an example of a transmission tower foundation constructed according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 excavated part excavated the area of foundation formation 11 base concrete 12 fixing point of tensile material 13 tensile material 2 leg of base body 21 main bar of columnar bar 22 hoop bar of columnar bar 23 base bar of base bar 3 columnar type Frame 3A Pillar base formwork 3B Pillar upper formwork 3a Pillar formwork vertical split unit 3b Pillar formwork vertical split unit 30 Pillar formwork cage frame 31 Top formwork upper hoop frame 32 Upper formwork lower end Hoop frame 33 Intermediate hoop reinforcement of column formwork 34 Vertical reinforcement of column formwork 35 Vertically attached single pipe pipe of column formwork 36 Mesh panel lining basket frame of column formwork 37 Vertical unit vertical Column joints at directional joints 38 Column joints at vertical joints of vertical split units 4 Scaffolding for work 41 Joining welds No. 42 No. 43 No. 5 fastening part 5 Window holes of pillar formwork 6 Base body pillar body G Target ground S Base T Backfill material W Concrete pump truck

Claims (2)

(57) [Claims] A power transmission tower base body having an excavated construction area is provided with a base material, a columnar bar and a base bar at an excavated bottom of a ground to be formed to form a base of the transmission tower base. A column base formwork in which a basket frame is covered with a mesh panel is installed, base concrete is poured, and a basket form formed in the shape of the upper structure of the power transmission tower base body on the base form is meshed. A method for constructing a power transmission tower foundation, characterized by placing an upper formwork lining with panels, setting and pouring ready-mixed concrete into the formwork and backfilling it. 2. A panel in which a form frame formed by covering a cage frame formed in the outer shape of a transmission tower foundation with a net panel is divided into several horizontal units, vertically divided units, or vertically and horizontally. A column formwork for constructing a power transmission tower base, wherein the form is divided into units and window holes for injecting ready-mixed concrete are provided on side walls of the units as appropriate.