JP5096029B2 - Concrete tower-like structure and manufacturing method thereof - Google Patents

Description

  The present invention relates to a concrete tower structure and a method for producing the same. More specifically, the present invention relates to a structure of a structure having a relatively low height, such as a column for wind power generation, and a technique for easily and inexpensively manufacturing the structure.

  An ultra-high-strength mortar tower-like structure that is superior in durability and economy compared to a steel tower-like structure has been developed (see, for example, Patent Document 1).

  The tower structure made of ultra-high strength mortar is constructed by transporting precast segments made of ultra-high strength mortar manufactured at the factory to the site and introducing the prestress in the vertical direction to integrate the segments. is there. By using ultra-high strength mortar, a tower-like structure having the same height as that of steel can be realized with a cross-sectional dimension comparable to that of steel.

However, when the height of the tower-like structure is relatively low, it is considered uneconomical to make all of the tower bodies of the tower-like structure into ultra-high strength mortar.
Application for Japanese Patent Application No. 2006-221407

  In the present invention, in a tower structure made of prestressed concrete having a relatively low height, for example, a height of about 10 to 30 m, in order to increase the economy, most of the ordinary concrete is used, and only a part thereof is super high. An object of the present invention is to provide a technique for realizing an inexpensive tower-like structure by using a strength mortar.

The present invention has been made to solve the above problems, and is characterized by taking the following technical means. That is, the present invention provides a precast prestressed concrete column in which a multi-stage segment made of ultra-high strength mortar is interposed in the longitudinal intermediate portion as a fixing portion of a PC tendon, and the tower body concrete other than the fixing portion is ordinary concrete. It is a concrete tower-like structure characterized by comprising a body.

  In tower structures made of prestressed concrete with a relatively low height, ultra-high-strength mortar is expensive, so high strength is required only in parts where high strength is required, such as PC tension material fixing parts and tower bases. By using mortar and using ordinary concrete in other parts, an inexpensive tower-like structure can be realized.

  The tower-like structure of the present invention is manufactured by producing a plurality of short segments made of ultra-high strength mortar, and attaching the short segments to each end of a hollow cylindrical mold for concrete in a tower main body that is horizontally connected. A tower using a member produced by a method for producing a tower-like structure, characterized in that concrete is placed in the interior, and a precast tower body concrete having a joint surface between the segment and the tower body concrete as a match cast surface is produced. It is possible to suitably construct the structure.

  In this method, the PC tension member fixing part segment and the tower base member are manufactured in advance, and these are attached to the tower body concrete form and the tower body concrete is manufactured by the match cast method. Therefore, it is possible to prevent concentrated stress at the joint, to prevent corner breakage, and to improve manufacturing accuracy.

  According to the present invention, in a tower structure made of prestressed concrete having a comparatively low height, an ultra-high strength mortar that is expensive only in a portion where high strength is required, such as a PC tendon fixing portion and a tower base. By using inexpensive ordinary concrete for other parts, an inexpensive tower-like structure can be realized.

  In addition, PC tension member fixing part segment and tower base member are manufactured in advance by ultra-high strength mortar, and these are used as a form of ordinary concrete cylinder, and the joint surface is manufactured by match cast method. In addition, it is possible to prevent the segment seam portion from being cut and corner breakage, and to improve the manufacturing accuracy.

  Embodiments of the present invention will be described below with reference to the drawings.

  In the present invention, an ultra-high-strength fiber reinforced mortar is partially used for the fixing portion of the PC tendon, so that a tower-like structure with excellent economy is constructed with ordinary concrete.

  1 is a side view of an embodiment of the tower-like structure of the present invention, and FIGS. 2 to 7 are AA, BB, CC, DD, EE, and FF of FIG. It is an arrow view. 2 and 4 to 7 show segments made of ultra-high-strength mortar in the fixing portion.

  The tower-like structure 1 is erected on the foundation 60 and is formed by stacking cylindrical tower body concrete 70, 80, 90, 100, 110. The tower-like structure 1 contains a PC tendon 120 from the foundation 60 to the top, and a fixing portion is provided at the joint of the cylindrical tower body concrete 80, 90, 100, 110. As the fixing portion, segment rings 10, 20, 30, 40, 50 made of ultra high strength fiber reinforced mortar are used.

  FIG. 2 is a plan view of the lowermost segment ring 10 (viewed along arrow A-A in FIG. 1) and includes 16 PC tension material insertion holes (sheaths) 11.

  FIG. 3 is an BB arrow view of FIG. 1 and shows an end face of the lowermost cylindrical segment ring 70. Sixteen PC tendon insertion holes (sheaths) 71 are shown.

  FIG. 4 is a plan view of the segment ring 20 as viewed in the direction of arrows CC in FIG. The PC tendon is fixed to the fixing plate 23 arranged in the four insertion holes 22 out of the 16 PC tendon insertion holes 21.

  FIG. 5 is a plan view of the segment ring 30 as viewed in the direction of arrows DD in FIG. There are twelve PC tension material insertion holes 31, and four of the insertion holes 32 are provided with fixing plates 33.

  6 is a plan view of the segment ring 40 as viewed from the direction of arrows E-E in FIG. 1. Of the eight PC tendon insertion holes 41, four insertion holes 42 are provided with fixing plates 43, and FIG. The four PC tension member insertion holes 51 in FIG.

  8 and 9 illustrate the size of the fixing plate in the case of ordinary concrete and the size of the fixing plate in the case of ultra high strength fiber reinforced mortar. For example, the dimension b of the fixing plate when the segment ring 20 is made of ultra-high strength fiber reinforced mortar is shown in FIG. 9 with respect to the dimension a of the fixing plate 25 shown in FIG. 8 when the segment ring 20 is ordinary concrete. In addition, it becomes half of the dimension a. Therefore, the wall thickness of the segment ring 20 may be thin.

  FIG. 10 is explanatory drawing which shows the manufacturing process of the cylindrical concrete of the tower-shaped structure which concerns on this invention. Segment rings 20, 30, 40, 50 made of ultra-high-strength fiber reinforced mortar are pre-manufactured, placed on the end face of each tower body concrete formwork, and concrete is cast into the form frame to form tower body concrete. 80, 90, 110 are manufactured. In this way, it is possible to manufacture cylindrical concrete whose end face is match cast molded with the end face of each segment ring.

FIG. 11 is a perspective view showing one segment ring 40 of the segment rings.

  Next, examples (design examples) of the present invention will be described.

In the example, a segment of an ultra high strength fiber reinforced mortar having a design standard strength of 120 N / mm ² was used only for the fixing portion of the PC tendon, and ordinary concrete having a design standard strength of 60 N / mm ² was used for the other parts. It is a tower-like structure made of prestressed concrete.
1. Design condition 1) Column height: H = 25,000m
2) Column diameter Top: D1 = 0.70m (outer diameter)
Base: D2 = 1.100 m (outer diameter)
3) Structure type: Prestressed concrete structure
(Design standard strength 60N / mm ² , using super high strength fiber reinforced mortar segment only for PC tension material fixing part)
5) Materials used:
Table 1 shows the characteristic values of the materials used for the tower body and the PC tendon fixing part. Concrete with a design standard strength of 60 N / mm ² is used for the tower body, and ultra-high strength fiber reinforced mortar with a design standard strength of 120 N / mm ² is used for the PC tension material fixing part.

6) Load and limit values:
Table 2 shows the load and limit values. The signs of loads in Table 2 are as follows.
G: Fixed load, P: Load capacity, W: Wind load, K: Seismic load, Co: Standard shear force coefficient (horizontal seismic intensity)

7) Fixing part of PC tendon:
By using a segment ring made of ultra high strength fiber reinforced mortar with a design standard strength of 120 N / mm ² , one side of the support plate of the PC tension material fixing portion can be reduced from 135 mm to 75 mm. Accordingly, the member thickness of the PC tendon fixing portion can be reduced from 195 mm to 150 mm, and the member thickness of the entire tower-like structure can be reduced by about 25%. (See FIGS. 8 and 9).
8) Precast tower body concrete manufacturing method:
The fixing portion (segment ring made of ultra high strength fiber reinforced mortar) for fixing the PC tendon is made of ultra high strength fiber reinforced mortar having a design standard strength of 120 N / mm ² . This fixing part (segment ring) is manufactured in advance and used as a formwork for placing the tower body concrete. The joint surface between the segment ring and the tower body concrete is match cast. As a result, it is possible to prevent concentrated stress and corner breakage from occurring at the joint between the tower body concrete and the segment ring when pre-stress is introduced, and the manufacturing accuracy is also the same.
2. Results of verification Verification was performed for constant loads, seismic loads and wind loads. Here is the result of the most critical wind load.
1) Review at reference wind speed (G + P + W) As shown in Table 3 and FIGS. 12 and 13, both the compressive stress level of concrete and the tensile stress level of PC tendon at the reference wind speed are below the limit values.

2) Review during storm (G + P + 1.6W) As shown in Table 4 and FIG. 14, the bending moment acting on the tower body during the storm is below the bending strength Mu, which is the limit value.

It is a side view of the tower-like structure of an Example. It is an AA arrow line view of FIG. It is a BB arrow line view of FIG. It is CC arrow line view of FIG. It is a DD arrow line view of FIG. It is an EE arrow line view of FIG. It is a FF arrow line view of FIG. It is a top view of a bearing plate of ordinary concrete. It is a top view of the bearing plate of an Example. It is explanatory drawing of the manufacturing process of an Example. It is a perspective view of a segment ring made of ultra high strength mortar. It is a stress line figure of concrete at the time of a standard wind speed. It is a stress line figure of PC tendon at the time of standard wind speed. It is a bending moment diagram at the time of a storm.

Explanation of symbols

1 Tower-like structure 10, 20, 30, 40, 50 Segment ring 11, 21, 31, 41, 51, 71 PC tension material insertion hole (sheath)
22, 32, 42 Insertion hole 23, 33, 43, 53 Fixing plate 60 Foundation 70, 80, 90, 100, 110 Tower body concrete 120 PC Tensile material

Claims (2)

It is composed of precast prestressed concrete pillars in which a multi-stage segment made of ultra-high strength mortar is interposed in the longitudinal middle as a fixing part for PC tendons, and the tower body concrete other than the fixing part is ordinary concrete. Characteristic concrete tower structure.   A plurality of short segments made of ultra-high-strength mortar are manufactured, and the short segments are attached to each end of a hollow cylindrical mold for tower body concrete that is horizontally connected, and concrete is placed in the mold, A method for producing a tower-like structure, comprising producing precast tower body concrete having a joint surface with the tower body concrete as a match cast surface.

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