KR20150057581A

KR20150057581A - Level adjusting apparatus for precast slab and precast slab construction method using therewith

Info

Publication number: KR20150057581A
Application number: KR1020130141104A
Authority: KR
Inventors: 이상윤; 송재준; 이영호; 박경훈
Original assignee: 한국건설기술연구원
Priority date: 2013-11-20
Filing date: 2013-11-20
Publication date: 2015-05-28

Abstract

A hollow height adjusting bolt including a top bolt portion and a bottom bottom portion formed integrally with the top bolt portion and having a horizontal through hole is horizontally embedded in a vertical hole formed in the precast slab, Cast slab, and the pre-cast slab can be adjusted in height, the upper bolt is recovered from the lower-end buried portion, and the concrete slab is fixed to the bridge upper structure by using a fixed anchor to precisely control the height of the precast slab And a precast slab construction method using the same.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pre-cast slab and a precast slab,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a step adjustment device for precast slabs and a precast slab construction method using the same. More precisely, it is possible to precisely adjust the level difference of the precast slab and to separate and reuse a part of the height adjusting bolt so that the precast slab can be installed more efficiently and economically, and And a method of constructing a precast slab.

Generally, road pavement types are classified into asphalt concrete pavement (commonly referred to as asphalt pavement) and cement concrete pavement (commonly referred to as concrete pavement), which are largely flexible pavements.

Such asphalt pavement refers to a pavement having a surface layer formed by combining aggregates with bituminous material, and generally consists of a surface layer, an intermediate layer, a base layer, and an auxiliary layer (including a frost layer). This type of asphalt pavement uses a material with a higher elastic modulus going to the upper layer, so that the load transferred from the upper layer during the traffic load operation is dispersed gradually and widely, and the vertical stress and the shear stress generated are supported by the hearth. It should be balanced and able to withstand traffic loads.

Such asphalt pavement is also referred to as flexible pavement, focusing on the mechanical behavior of the pavement.

Concrete pavement technology is introduced. Such a concrete pavement is a wrapping type in which the concrete slab itself behaves like a beam and supports the stress generated by the traffic load by the bending resistance.

These concrete pavements are generally composed of a surface layer (concrete slab), an auxiliary layer (for example, lean concrete) and an anti-frost layer. The role of the auxiliary layer is to provide an even bearing force on the surface layer and a frost heave phenomenon And to provide a stable work base for laying concrete slabs.

In such a concrete pavement, a plurality of precast slabs are connected and installed. In order to secure the slope of the slab, the height of the concrete slab should be adjusted.

In order to adjust the height of the precast slab in the road pavement method using the precast slab, there are conventionally used methods such as a height adjusting method using a rubber pad, a bolt type elevating concrete height adjusting method, and a height adjusting method using an iron plate have.

1 shows a method of adjusting the height of the precast slab, in particular, by using a bolt for height adjustment.

That is, the conical groove 11 formed in the precast slab 10 is formed in advance, and the socket portion 13 is formed so that the lower groove 12 is embedded in the lower end of the conical groove, .

It can be seen that the height adjusting bolt 22 is fixed to the socket portion 13 and the height adjusting bolt 22 is rotated using the jig 30 to adjust the height of the precast slab 10.

At this time, the conical groove 11 is closed with a filling material such as non-shrinkable mortar. It can be seen that the height adjusting bolt 22 is embedded in the conical groove 11 by such finishing. However, the method of fixing the height adjusting bolt 22 to the socket portion of the conical groove 11 by the fastening nut 21 may have a problem of stability of the precast slab which is a heavy material, and it is difficult to precisely adjust the level difference .

In particular, in the case of a precast slab for bridges as in the present invention, it is necessary to fix the precast slab in a horizontal state on the upper surface of a girder or the like. However, the conventional simple height adjusting bolt has some limitations in application.

Accordingly, it is an object of the present invention to provide a precast slab precast concrete slab precast concrete precast concrete precast casting apparatus, And to provide a slab construction method.

Also, it is a technical problem to solve the problem of providing a step-adjusting device for a pre-cast slab capable of constructing a more economical and efficient precast slab by allowing a part of the height adjusting bolts installed in the precast slab to be recovered and providing a method of constructing a precast slab using the same do.

In order to achieve the above technical object

First, a step adjustment device for precast slabs is provided. The step adjustment device for precast slabs is installed by using a buried nut formed inside a vertical hole of a precast slab, and a hollow height adjusting bolt In the state of being fastened, the precast slab step is adjusted through the rotation (using a jig) of the hollow height adjusting bolt.

Secondly, in the state where the final height adjustment is completed, the bottom embedding portion of the hollow height adjusting bolt is buried by the filler to support the precast slab, and the upper bolt portion is separated from the bottom buried portion and recovered. This allows efficient and economical operation through the recovery of a part (upper bolt part) of the hollow height adjusting bolt.

Third, the pre-cast slab is pressed and fixed to the bridge upper structure stably by using a fixing anchor and an elastic washer so as to penetrate through the lower-end buried portion and be embedded and fixed on the upper surface of the bridge upper structure.

The height of precast slab can be adjusted more precisely by using the step adjustment device for precast slab according to the present invention, and the precast slab can be stably set by the bottom embedded part of filler, buried nut and hollow height adjusting bolt .

In addition, since the lower-end buried portion serves as a fixture for fixing the precast slab to the bridge overhead structure, the construction of the precast slab for bridge can be simplified and the workability can be improved.

In addition, since the upper bolt portion corresponding to the body portion of the hollow height adjusting bolt can be recovered, it is possible to utilize the height adjusting bolt more efficiently and economically.

1 is a construction cross-sectional view of a height-adjusting bolt for a conventional precast slab,
FIGS. 2A and 2B are a perspective view and a perspective view, respectively, of a step adjustment device for precast slabs according to the present invention;
3 is a construction diagram of a precast slab and a bridge overhead structure using the step adjustment device for precast slab of the present invention,
FIGS. 4A, 4B and 4C are a construction flowchart of a precast slab using a step adjustment device for precast slabs according to the present invention. FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

[Level adjustment device for precast slab (100)]

FIGS. 2A and 2B show a perspective view and a perspective view of a step adjustment device 100 for precast slabs according to the present invention.

The step adjustment device 100 for a precast slab includes a hollow height adjusting bolt 120 including a buried nut 110, a lower end buried portion 121, and a top bolt portion 122.

First, referring to FIG. 2A, a precast slab 200 can be identified. The precast slab may be a reinforced concrete member having a predetermined thickness and having a predetermined length and width.

The precast slabs 200 are used for bridges and must be fixedly installed on the upper surface of the bridge superstructure 300 such as girders and transverse beams.

For this purpose, a vertical hole 210 is formed in the precast slab 200 so that a precast slab adjustment device 100 is installed through a vertical hole 210, and the precast slab adjustment device 100, The height is adjusted.

This height adjustment is required to adjust the slope of the slab, which is the bridge superstructure, so as to prevent the formation of steps of the precast slab 200 due to a construction error or the like in connecting a plurality of precast slabs 200 to each other .

First, the buried nuts 110 are arranged to be partially buried in the middle of the vertical holes 210 using a nut such as a circular plate, while partially exposing the upper surface of the buried nuts 110 while exposing the central fastening holes 113.

Accordingly, the buried nuts 110 are fixedly set before the precast slab 200 is manufactured, so that a separate installation work is not required.

At this time, as shown in FIG. 2A, the buried nuts 110 are formed with an expansion block 111 protruding from the outer circumferential surface, for example, so as to be able to stably position the concrete when pouring concrete.

The hollow height adjusting bolt 120 may include a lower end buried portion 121 and an upper end bolt portion 122. The lower end buried portion 121 and the upper end bolt portion 122 may be vertically coupled to each other, So that they can be separated from each other.

The lower landfill portion 121 is formed as an arm socket portion having a central through hole 123 formed therein so that a wedged upper groove 124 is formed around the upper portion of the central through hole 123, So that the lower end fastener 125 of the upper bolt portion 122, which will be described later, can be fastened.

The horizontal buried hole 127 is formed in the bottom buried portion 121 so that the filling material 140 can be injected into the spacing space S through the central through hole 123. The horizontal through hole 127 is formed in the bottom buried portion 121, And communicates with the central through hole 123.

The upper end of the upper bolt portion 122 is formed with a central through hole 123 and a male threaded portion formed on the outer circumferential surface of the upper bolt portion 122. The lower end of the upper bolt portion 122 is connected to a lower end fastener 125 .

The lower end fastener 125 is formed to have a diameter smaller than that of the upper body portion 126 so that the upper body portion 126 of the upper bolt portion 122 is vertically aligned with the lower end embedded portion 121 So that it can be concluded.

At this time, it is understood that the central through hole 123 of the upper bolt portion 122 and the central through hole 123 of the lower end embedded portion are arranged to be vertically communicated with each other.

When the upper end bolt portion 122 is rotated in a state where the lower end end portion 121 is embedded in the lower portion of the upper bolt portion 122 and is fixed by the filler 140 as shown in FIG. .

At this time, a male screw part is formed on the outer circumferential surface of the upper body part 126 to be fastened to the central fastening hole 113 of the embedding nut 110, so that the hollow height adjusting bolt 120 can be lifted and lowered by stable rotation .

In other words, the hollow height adjusting bolt 120 of the present invention can be lifted up and down while being fastened along the central fastening hole 113 of the buried nut 110 formed in the vertical hole 210 of the precast slab 200, The height of the stable precast slab 200 can be adjusted.

The upper and lower central through holes 123 can be easily filled in the spacing space S between the bottom surface of the precast slab 200 and the upper surface of the bridge upper structure 300 It is important to note that

Referring to FIG. 2B, the operation of the hollow height adjusting bolt 120 of the present invention can be seen.

The hollow height adjusting bolt 120 is rotated and coupled through the central fastening hole 113 of the buried nut 110 so that it can be lowered and raised from the upper portion of the vertical hole 210 And the bottom surface of the lower end embedding portion 121 of the hollow height adjusting bolt 120 contacts the upper surface of the bridge upper structure 300 to set the height of the final precast slab 200.

The filling material 140 is injected through the central fastening hole 123 of the hollow height adjusting bolt 120 so as to fill the space S between the precast slab 200 and the bridge upper structure 300, The upper end bolt portion 122 is separated from the lower end buried portion 121 by using a jig (not shown, using a jig groove on the upper end surface of the upper bolt portion 122) .

That is, a portion (upper bolt portion) of the hollow height adjusting bolt 120 can be recovered, but the remaining pre-cast slab 200 can be stably supported by the lower end buried portion 121.

The lower end of the fixed anchor 400 is inserted into the fixing hole 310 formed on the upper surface of the bridge upper structure 300 through the central fastening hole 123 of the remaining lower end embedded portion 121 .

At this time, the upper end of the fixed anchor 400 is formed with a male screw so that the fixing nut 410 can be fastened. The elastic washer 420 is inserted into the bottom surface of the fixing nut 410 fastened to the upper end of the fixed anchor,

When the fixing nut 410 is rotated to move downward in a state where the elastic washer 420 is supported on the upper surface of the embedding nut 110 of the precast slab 200,

The pre-cast slab can be fixedly fixed to the bridge upper structure 300 by the fixed anchor 400. [

Further, if the fixing nut 410 is loosened, the fixing anchor can be removed, so that the precast slab can be easily dismantled.

[Method of fixing precast slab 200 by using level adjusting device 100 for precast slab]

3, the buried nuts 110 are formed in the pre-cast slab 300 in the vertical holes 210 in advance. This will be described with reference to FIG.

The step adjustment device 100 for precast slabs in which the lower end buried portion 121 and the upper end bolt portion 120 of the present invention are vertically integrated is inserted into the center fastening hole 113 of the buried nuts 110 using a jig, Cast slabs 200 may be installed by adjusting the height of the precast slabs 200 so that the adjacent precast slabs 200 may be installed using the precast slab adjustment device 100 .

The upper bolt portion 122 of the step adjustment device 100 for the precast slab is recovered and the precast slab 200 is recovered using the filler 140 And the spacing space S between the bridge upper structure 300 and the bridge upper structure 300 are filled up so that the lower end buried portion 121 is embedded in the filler material 140 so that the stable setting of the precast slab 200 can be performed stably.

At this time, an elastic material 320 may be used to prevent leakage of the filled filler material 140, and a sealing material may be used to seal the space between the lower end of the vertical hole 210 and the lower- So that leakage and exponent of the filler material are made possible.

Since this state is such that the precast slab 200 is simply fixedly supported on the bridge superstructure 300, the present invention can be applied to the precast slab 200 by using the fixed anchor 400, the fixing nut 410 and the elastic washer 420 200 to the bridge superstructure 300.

The fixed anchor 400 is inserted into the fixing hole 310 formed on the upper surface of the bridge upper structure 300 through the central fixing hole 123 of the lower landing end 121, The upper end of the pre-cast slab 200 is fastened by the elastic washer 420 to the buried nut 110 formed in the vertical hole 210 of the precast slab 200 by the fixing nut 410.

The elastic washer 420 has a function of pressing and fixing the concrete slab 200 to the bridge upper structure by the fixed anchor 400.

Further, the vertical hole 210 formed in the concrete slab 200 is closed by installing the cap 160 at the upper end of the vertical hole 210 without finishing the final non-shrinkable mortar.

This is to enable the precast slab 200 to be easily disassembled from the bridge superstructure 300 through the removal of the fixed anchor 400 in the future.

[Construction method of precast slab (200) using step adjustment device 100 for precast slab]

4A, 4B and 4C show a flowchart of a method of constructing a precast slab 200 using the step adjustment device 100 for precast slabs.

First, as shown in FIG. 4A, the bridge superstructure 300 includes piers, alternatingly mounted girders, and the girders are constrained transversely to each other by the transverse beams.

The precast slab 200 may be fixed to the bridge superstructure 300 such that the precast slab 200 is fixed to the girder or the upper surface of the transverse beam.

In the precast slab 200, a vertical hole 210 is formed by inserting a PVC pipe inside the mold, and the PVC pipe is vertically supported by upper and lower vertical bars on the upper and lower sides, And the buried nuts 110 are formed and exposed in the inside of the vertical holes.

In addition, it can be seen that the level adjustment device 100 for precast slab of the present invention is initially set in the buried nuts 110.

As shown in FIGS. 4A and 4B, the level adjustment apparatus 100 for a precast slab is used to mount the pre-cast slab 200, which is initially set, to the bridge superstructure 300.

At this time, the elastic material 320 is previously disposed on the upper surface of the bridge upper structure 300 so that the pre-cast slab 200 having the initial setting of the precast slab adjustment device 100 is mounted at a predetermined height.

Next, the final height of the precast slab 200 is precisely set while rotating the step adjustment device 100 for the precast slab, which is initially set by the buried nut 110.

This final height setting will be an operation of adjusting the height of the desired precast slab 200 by adjusting the step adjustment device 100 for each precast slab considering the slope of the slab and the like.

4b, the filler material 140 is adhered to the elastic material 320 through the center through hole 123 of the step adjustment device 100 for the precast slab, which is installed at the lower end of the vertical hole 210 using a sealing material, Is filled in the spacing space (S) between the precast slab secured by the slab adjustment device (100) and the bridge estuary trough.

The filler 140 may be made of a non-shrinkable mortar so that it can be prevented from leaking or leaking by the elastic material 320 even if it is filled in the spacing space S,

Since the bridge upper structure and its bottom face are not completely in contact with each other at the height adjusting stage of the level shifting apparatus 100 for precast slab, filling of the filling material 140 can be sufficiently performed through high pressure filling, So that horizontal filling holes 127 are additionally formed to facilitate filling.

When the filler material 140 filled in the spacing space S is cured, only the upper bolt part 120 constituting the step difference adjusting device 100 for precast slabs is recovered using a jig as shown in FIG. 4C, The fixing hole 310 is formed on the upper surface of the bridge upper structure 300 through the central through hole 123 of the lower landfill portion 121 by using a drill or the like to install the bridge structure 400.

The lower end of the fixed anchor 400 is inserted through the vertical hole 210 of the precast slab 200 into the fixing hole 310 via the central through hole 123 of the lower end of the embedding 121, A fixing nut 410 is mounted on the upper surface of the elastic washer 420 so as to be supported on the upper surface of the buried nut 110 and a fixing nut By continuing to rotate,

The precast slab 200 can be pressed and fixed to the bridge upper structure 300 by the fixed anchor 400.

The vertical hole 210 of the precast slab 200 is closed with the cap 160. If necessary, the cap is removed and the fixing nut of the fixing anchor is loosened to remove the fixing anchor, It becomes possible to further disassemble from the superstructure 300.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

100: Level adjustment device for precast slab
110: buried nut 111: expansion block
113: Central fastening hole
120: Hollow height adjusting bolt
121: bottom buried portion 122: top bolt portion
123: central through hole 124: upper groove
125: lower end fastener 126: upper body part
127: Horizontal penetration hole
140: filler
200: Precast slab
210: Vertical hole
300: bridge superstructure
310: Fixing hole 320: Elastic material
400: Fixing anchor 410: Fixing nut
420: Elastic washer

Claims

A buried nut 110 horizontally embedded in an inner surface of a vertical hole 210 formed in the precast slab 200 so that a central coupling hole 113 and a part of a top surface of the vertical hole 210 are exposed; And
An upper bolt portion 122 having a threaded portion formed on an outer circumferential surface thereof to be fastened to the central fastening hole 113 and a lower end fastening hole 125 having a threaded portion formed on a lower end of the upper bolt portion 122, And a lower leveled bolt 120 including a bottom portion 122 and a lower end fastener 125 fastened to the upper groove 124 of the upper surface to be integrated with each other,
Wherein the hollow height adjusting bolt 120 is rotatably coupled to the central fastening hole 113 of the buried nut 110 to adjust the height of the precast slab 200. [ .

The method according to claim 1,
The center bolt 123 is connected to the upper bolt portion 122 and the lower end buried portion 121 of the hollow height adjusting bolt 120 so that the filler 140 is inserted through the central through hole 123, Through the horizontal through hole 127 formed in the lower end buried portion 121, to be filled in the spacing space S between the precast slab 200 and the bridge upper structure,
And an expansion block (111) is further formed on an outer circumferential surface of the buried nut (110).

3. The method of claim 2,
The upper end bolt portion 122 is rotated from the lower end buried portion 121 by using the jig in a state where the filler 140 is hardened and the lower end buried portion 121 of the hollow height adjusting bolt 120 is buried and fixed So that the pre-cast slab is separated and reused.

The method of claim 3,
The fixing anchor 400 is inserted into the central through hole of the lower end embedded portion 121 in which the upper bolt portion is separated and the lower end of the fixing anchor is inserted into the fixing hole 310 formed on the upper surface of the bridge upper structure 300,
An elastic washer 420 is inserted into the upper end of the fixed anchor 400 so that the elastic washer 420 is supported on the upper surface of the filling nut 110. A fixing nut 410 is fixed to the upper surface of the elastic washer 420 So that the pre-cast slab (200) is pressed and fixed to the bridge upper structure (300) by the fastening anchor (400).

3. The method of claim 2,
The elastic material 320 is further installed in the spacing space S so that the filling material 140 to be filled is prevented from leaking or leaking and the sealing material is further formed at the lower end of the filling bottom end 121 and the vertical hole 210 Wherein the pre-cast slab is a slab.

(a) An elastic material 320 is installed on the bridge upper structure 300 and then the precast slab 200 is mounted on the bridge estuary structure 300 so that the precast slab 200 is supported on the elastic material 320, Allowing a spacing space (S) to be formed between the bottom surface and the bridge top structure (300); And
(b) an upper surface is exposed in the vertical hole 210 of the precast slab 200, and the precast slab 200 is formed on the outer circumferential surface of the center coupling hole 113 of the buried nut 110, Adjusting the height of the precast slab 200 by rotating the hollow height adjusting bolt 120 while the hollow height adjusting bolt 120 of the step adjuster 100 is fastened, &Lt; / RTI &
The buried nuts 110 are horizontally embedded in the inner surface of the vertical hole 210 formed in the precast slab 200 to expose a part of the upper surface of the middle coupling hole 113,
The hollow height adjusting bolt 120 includes a top bolt portion 122 having a threaded portion formed on an outer circumferential surface thereof so as to be fastened to the center fastening hole 113 of the buried nut. An upper bolt portion 122 formed integrally with a lower end fastener 125 having a threaded portion formed on an outer circumferential surface of the lower end of the upper bolt portion 122 and a lower end fastener 125 fastened to the upper groove 124 of the upper surface And a lower-end buried portion (121) integrally formed with the lower-level buried portion (121).

The method according to claim 6,
After the step (b)
The filler 140 is inserted into the horizontal through hole 127 of the lower end buried portion through the upper bolt portion 122 of the hollow height adjusting bolt 120 and the central through hole 123 communicated with the lower end buried portion 121 Thereby filling the spaced space S between the precast slab 200 and the bridge overhead structure so that the filled filler material 140 is hardened so that the lower-stage buried portion 121 is buried in the filler material Wherein the pre-cast slab is slab-like.

8. The method of claim 7,
The upper end bolt portion 122 is rotated from the lower end buried portion 121 by using the jig in a state where the filler 140 is hardened and the lower end buried portion 121 of the hollow height adjusting bolt 120 is buried and fixed Separated,
The lower end of the fixed anchor is inserted into the fixing hole 310 formed on the upper surface of the bridge upper structure 300 by inserting the fixing anchor 400 into the central through hole of the lower end embedded portion 121,
An elastic washer 420 is inserted into the upper end of the fixed anchor 400 so as to be supported on the upper surface of the embedded nut 110. A fixing nut 410 is fastened to the upper surface of the elastic washer 420, Further comprising the step of causing the anchor (400) to press and secure the precast slab (200) to the bridge overhead structure (300).