JP3436104B2 - Steel pipe construction method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laying method suitable for work such as laying and fixing a steel pipe used for a high pier. 2. Description of the Related Art In a hybrid slip method adapted to a pier, a plurality of steel pipes are erected in advance at positions to be pillars, and a vertical main reinforcing bar and an outer periphery thereof are surrounded by a steel pipe. This is a method of constructing an integrated pier structure sequentially from the bottom by laying a PC strand around and arranging reinforcement, and then placing concrete inside the form while raising the slip form form. [0003] In this construction method, since complicated assembling work such as a hammering bar at a corner and an assembling reinforcing bar in addition to a main reinforcing bar and a transverse bar, which is a conventional reinforcing bar reinforcing structure, is eliminated, column strength is particularly required. This method is suitable as a pier structure such as a high pier, which is a high-rise structure, and is also suitable for shortening the construction period. [0004] In this construction method, as a construction procedure, a steel pipe is erected on a foundation, position adjustment, assembling of a work scaffold, and assembling of a brace are carried out. Add steel pipe. [0005] After that, the vertical main reinforcement is pre-assembled, then the reaction force gantry is assembled to the top of the steel pipe, the slip-form form is assembled, and the reaction steel gantry is connected to the reaction gantry by PC steel wire.
While raising the form by the reaction force jack, the concrete laying work inside the form and the preceding work of winding the PC strand are performed up to the upper part of the pier to complete the pier. [0006] Thereafter, the work is completed by lowering the formwork, dismantling and removing, removing the reaction force stand and the work scaffold. [0007] As shown in FIG. 3, a method of installing a steel pipe in each of the above steps is as follows.
After the work scaffold 3 is assembled, the upper steel pipe 2 is suspended by the large crawler crane 4 above the reference steel pipe 2 and is fixed on the lower steel pipe 2, and then joined by welding. Repeat the process of adding parts up to the top. [0008] The figure shows the case when viewed from the side. Two steel pipes 2 are built in parallel, but when viewed from the front, four steel pipes are arranged side by side. When performing the work, the erection work is performed in units of a total of eight steel pipes 2. Conventionally, in this case, the work of arranging is performed by a bracket 2a protruding around the upper part of the existing steel pipe 2 and a lower part of the suspended steel pipe 2 as shown in FIG. A connecting member 5 of a wire or a turnbuckle type is suspended between the provided brackets 2a. The connecting member 5 is seated on the upper part of the corresponding steel pipe 1 to store a load. Fine adjustment of. After this fine adjustment operation, as shown in FIG. 3B, the erection piece 6 is applied between the upper and lower brackets 2a, and the erection piece 6 is fixed to the bolt and nut 7 so as to be fixed. The crane wire hanging the steel pipe 2 was hung and removed, and the connecting portions were connected by field welding. [0011] However, the above positioning and fixing operation has the following problems. First, in the case of binding or pushing with the connecting member 5, if it is pulled too much, it takes time to return to the original position, so that fine adjustment work is difficult, and it takes a long time to complete positioning. I was Further, when the erection piece 6 is bolted, the steel pipe 2 moves in the circumferential direction depending on the degree of tightening, and the building position is often out of order. Was hanging. Further, since the positioning and the temporary fixing work take a long time, the crawler crane 4 has a long waiting time in a hung state, and it takes time until the next steel pipe is hung. Therefore, in order to secure the mounting accuracy,
Conventionally, at most about four erection works per day have been the limit, and these work forms have been a bottleneck in shortening the construction period. The present invention solves the above-mentioned problems, and a method for laying a steel pipe capable of quickly setting up a steel pipe without positional deviation in a temporary fixing work and performing a temporary fixing accurately. Is provided. In order to achieve the above-mentioned object, the present invention provides a plurality of flange brackets each having an opening formed in the upper and lower periphery of a steel pipe in a thrust direction of the steel pipe. A bolt that is held in a loosely fitted state by a level adjustment nut is inserted into a bolt hole of the upper flange bracket in the lower steel pipe in advance, and the upper steel pipe is installed on the lower steel pipe. By positioning the brackets facing each other and adjusting the rotation of the level adjustment nut, the tip of the bolt is inserted into the bolt hole of the lower flange bracket in the upper steel pipe, and the height adjustment nut screwed into the tip side of the level adjustment nut. By pressing against the lower surface of the lower flange bracket to determine the height of the bolt, the lower flange at the tip of the bolt By temporarily fixing the fixing nut to the upper protruding end from the bracket, both steel pipes are temporarily fixed, and then
The upper and lower joining edges of the steel pipe are welded while leaving the bolt portion, and then the bolt is removed and the remaining portion is welded. With the above arrangement, in the method of the present invention, the upper steel pipe is self-corrected so as to be positioned on the same axis with respect to the lower steel pipe by the bolting operation. Further, according to the present invention, since the erecting and the temporary fixing can be performed by bolting, the work can be performed quickly and accurately. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition,
In the figure, the same portions as those in the related art are denoted by the same reference numerals, and only different portions or newly added members will be described using different reference numerals. FIG. 1 shows a joint structure of a steel pipe to which the method of the present invention is applied, and FIG. 2 shows a procedure for installing the joint in the joint structure. In FIG. 1, four upper and lower flange brackets 10 are welded to the outer periphery of the upper and lower edges of the upper and lower steel pipes 2 at 90 ° intervals, respectively.
0 is a steel pipe 2 by a pair of reinforcing plates 12 respectively.
Is firmly fixed. At the center of each of the flange brackets 10, bolt holes 14, 15 are formed in the thrust direction of the steel pipe 2, and through the bolt holes 14, 15, bolts 16 and washers 18 are sequentially provided from the lower side. A level adjustment nut 20, a height adjustment nut 22, a washer 18 interposed at the upper end thereof, and a fixing nut 24 fixed to the tip of the bolt 16 through the lower flange bracket 10 are disposed. The bolt hole 14 on the upper flange bracket 10 has an inner diameter slightly larger than the outer diameter of the bolt 16, but the bolt hole 15 on the lower flange bracket 10 has a considerably larger outer diameter than the bolt 16. Yes, mounting errors during seating are allowed by this inner diameter. The installation procedure in the above configuration is shown in FIG.
(A) As shown in FIG.
The bolt 16 is inserted into the bolt hole 14 of the level adjustment nut 2 through the washer 18 at the lower side of the upper protruding end.
0, height adjusting nut 22 and washer 18
And the level adjusting nut 20 is retracted to a height position where the shaft end of the bolt 16 does not interfere with the lower edge of the upper steel pipe 2 into which the bolt 16 is hung. In this state, the upper steel pipe 2 is hung down,
As shown in (b), the lower steel pipe 2 is seated on the upper edge. In the seated state, the flange bracket 1
Although the 0s are almost vertically opposed to each other, they are not centered yet unlike the drawing. Immediately after seating, the level adjusting nut 20 is rotated and adjusted as shown in (c), the tip of the bolt 16 is projected to the upper surface of the lower flange bracket 10, and then the height adjusting nut 22 is raised. Then, the bolt 16 is pressed against the lower surface of the lower flange bracket 10 to position the protruding height of the bolt 16, and then the fixing nut 24 is screwed into the protruding end of the bolt 16 on the lower flange bracket 10 to be fixed. At this time, as shown in (d), when the seating position of the upper steel pipe 2 is shifted by d in the radial direction with respect to the lower steel pipe 2, the center axis of the bolt 16 is shifted, and furthermore, Although not vertically, it is inclined by an angle θ corresponding to the displacement amount d. In this state, the tightening adjustment of the nuts 20, 22, and 24 causes the axis of the bolt 16 to be vertical, and in this state, the central axis of the steel pipe 2 matches. After the nut is tightened, the parts are accurately matched and the temporary fixing operation is completed as shown in FIG. After the temporary fixing is completed, the crawler crane (see FIG. 3) can start the next work of hanging the steel pipe by hanging and hanging the crane wire. Thereafter, as shown in FIG.
Except for the four locations where 6 is fixed, the joints of the two steel pipes 2 are welded. Thereafter, as indicated by broken lines, the bolts 16, the nuts 20, 22, 24, and the washers 18 are removed, and this portion is welded. 26, the erection work is completed. The removed bolts and nuts can be diverted to the next erection work, or can be fixed to the mounting positions of the steel pipes 2 again for reinforcement. When the above work was carried out at the actual construction site of a high pier, the conventional work was 4 works / day at best, but the actual work speed was 8 works / day or more. It has been proved that it is possible to build steel pipes in units of eight in one day. Also, in this embodiment, the case where the splicing of steel pipes used in the slip form method for building a high pier is applied is shown. However, the present invention can be applied to other construction methods in which steel pipes are successively and vertically connected. Of course. As is clear from the above description, in the method for determining the construction of a steel pipe according to the present invention, the construction of the steel pipe can be performed quickly, and there is no displacement in the temporary fixing work.
Temporary fixing can be performed with high accuracy. Further, in the method of the present invention, only the fastening operation of the bolt and the three nuts screwed into the bolt can simultaneously perform the two operations of the mounting positioning and the temporary fixing, thereby simplifying the working form. There are advantages such as.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a joint structure of a steel pipe to which the present invention is applied. 2 (a) to 2 (f) are cross-sectional explanatory views showing the same procedure. FIG. 3 is an overall explanatory view showing a form in which a steel pipe is erected in a slip form method. FIGS. 4A and 4B are perspective views showing a conventional installation procedure. [Description of Signs] 2 Steel pipe 10 Flange bracket 14, 15 Bolt hole 16 Bolt 20 Level adjusting nut 22 Height adjusting nut 24 Fixed nut 26 Welding

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) E01D 19/02 E01D 21/00 E02D 13/00 E04B 1/58 E04C 3/30 E04F 17/00

Claims (1)

(57) [Claims 1] A plurality of flange brackets having bolt holes formed in the thrust direction of the steel pipe are fixed around the upper and lower sides of the steel pipe, and the upper flange of the lower steel pipe is fixed. A bolt which is held in a loosely fitted state by a level adjusting nut is inserted into the bolt hole of the bracket in advance, the upper steel pipe is installed on the lower steel pipe, the two flange brackets are positioned to face each other, and the level adjusting nut is By the rotation adjustment, the tip of the bolt is inserted into the bolt hole of the lower flange bracket of the upper steel pipe, and the height adjustment nut screwed into the tip side of the level adjustment nut is pressed against the lower surface of the lower flange bracket. The bolt height is positioned, and a fixing nut is fixed to an upper protruding end of the bolt tip from the lower flange bracket. By temporarily tightening the steel pipes, the two steel pipes are temporarily fixed to each other, and then the upper and lower joining edges of the steel pipes are welded except for the bolt portions, and then the bolts are removed and the remaining portions are welded. How to decide.