KR19980025917A - Multi-span prestressed steel composite continuous member and its construction method - Google Patents

Abstract

The present invention relates to a multi-span multi-span prestressed steel composite continuous member and a method of hypothesis of the composite steel and concrete, or a combination of the steel and concrete and tensile material, and conventionally the prestressed steel composite member composed of only I-shaped steel and concrete Since there are many difficulties in designing and constructing the continuous member 20 using the bar, the prestressed steel-molded member 100 can independently resist the center and branch portions of the continuous member 20 independently of each other. In order to introduce the prestressed compressive stress of the form can be separated into the center portion of the moment constant section 21 and the branch portion of the parent moment section 22, and then install the branch portion of the moment section section 22 first While the joint middle hypothesis section member 21 is constructed, the cone of the upper flange 22d and the slab 22e portion of the parent section section member 22 is According to the present invention, each section member (21) and (22) can be structurally continuous over its entire length by introducing a prestressed compressive stress to resist the parental moment of the section. Compared to the simple beam member 10 under the same condition, the section design, the maximum bending moment to resist the section members 21 and 22 can be reduced to significantly reduce the cross section, the mold height, the amount of use of the material, and the weight of the member. By using only one support 23 at each point, it is possible to easily install a continuous member, and there is no need to install a separate expansion joint in the middle. Not only can greatly reduce manpower consumption and work costs required for design, manufacture, and construction of construction, but also increase the safety of bridges. Effects can be obtained such as being able to be achieved axis.

Description

Multi-span prestressed steel composite continuous member and its construction method

The present invention relates to a multi-span multi-span prestressed steel composite continuous member and a method of hypothesis of the combination of the steel and concrete, or a combination of the steel and concrete and the tension member, more specifically, each of the composite elements, such as the steel and concrete, tension member It is to ensure that there are no expansion joints in the middle of the bridge by enabling structural continuous integration over the entire extension of the bridge.

The prestress steel molding method to which the present invention relates is for bridges developed in Belgium in the early 1950s, and loads a constant load (Pf load) on I-type girder made of high tensile steel. Introducing prestressed compressive stress to the lower concrete in the process of restoring the deflection by removing the preloaded load (Pf load) after curing concrete of a certain section in the lower flange part in the state of causing the deflection deformation. Say the public law.

This prestressed steel composite molding method has a smaller cross section than any other bridge construction method such as PC beam (Prestress Concrete Beam) method in a certain space and design load conditions, and in particular, the shape height is considerably lower so that the efficient use of the space can be achieved. There is an advantage.

On the other hand, in general, when a load acts on a member having a simple beam shape, each section (1st degree) Independently, only the positive moment (+ M) is generated for each of the two), the tension force (T) is generated in the lower edge of each section member 11 over the ground length as shown in Figure 2, the compression force (C) is generated in the upper edge.

However, in the continuous member 20 structurally continuous with the section member over the entire length of the member L, the parent moment (-M) is generated at a certain section of the point as shown in the third degree, and the positive moment (+ M) in the middle section. ) Occurs repeatedly.

Therefore, in the center portion of the section, which is the positive moment (+ M) section, as in the simple beam member 10 of FIG. 1, the tensile force T is generated at the lower edge of the section member 21 as in the fourth degree, and the compressive force C is applied to the upper edge. Although it is generated, the tension portion (T) is generated at the upper edge of the section member 22 as the fifth degree, and the compressive force (C) is generated at the point portion that is the parent moment (-M) interval.

In the above, the magnitude of the maximum static moment (+ M) generated in the simple beam member 10 under the constant length and load conditions is the absolute value of the maximum parent moment (-M) of the point portion generated in the continuous member 20 under the same conditions. It is almost equal to the sum of the value and the maximum static moment (+ M) value in the middle part of the center.

That is, at constant span and load conditions; * Maximum static moment (+ M) value of simple beam member ≒ The absolute value of maximum parent moment (-M) value of continuous member + maximum static moment (+ M) value of continuous member is established.

The above formula means that if the bridge is designed and manufactured by the continuous member 20, the size of the design maximum bending moment to be resisted can be significantly reduced than when designed and manufactured by the simple beam member 10.

In other words, if the bridge is designed and manufactured by the continuous member 20, the middle section of the bridge sets the maximum static moment (+ M) size of the section to design the maximum bending moment value, and at the point section, the maximum parent moment (- M) Set the size as the design maximum bending moment value, or design and manufacture the largest value of the maximum positive and parent moments as the design maximum bending moment value in the case where the upper and lower edges are symmetrical.

Therefore, in the case of designing and manufacturing hypothesis with continuous member 20 in the form of a constant span length and load, it reduces the design maximum bending moment value compared to the simple beam member 10 under the same conditions. In addition, it is possible to significantly reduce the self-weight, etc. On the contrary, when the continuous member 20 is applied when the cross-section of the member, the mold height, the amount of the material used, the self-weight, etc. are constant, The load or span length can be made larger.

On the other hand, in the two or more multi-span simple beam member 10, each section (like the first degree) Two supporters (13) are required to independently support the section member 11 for each section, and at each point, the expansion and contraction of the section member 11 according to the temperature change of the section member is extinguished for each section. Expansion joints (14) are to be installed to allow for this.

However, in the continuous member 20, only one support 23 is required for each point as shown in the third degree, and the member is expanded and contracted according to the temperature change integrally over the entire length, so that the point of time of the member and Only two joints are required at the end point, and no separate joint is required in the middle.

Prestressed steel composite member 100 according to the present invention is the abdominal (100c) after the pre-stressed compressive stress is introduced into the lower flange concrete (100b) according to the deformation of the I-shaped steel (100a: I type Girder) as shown in the sixth degree ) And by pouring and curing the concrete of the upper flange (100d) portion, it is synthesized only with steel and concrete.

The prestressed steel forming member 100 is developed to be adapted only to the static moment value according to the load action of the simple beam member, and the prestressed compressive stress introduced into the lower flange concrete 100b over the entire length is simple. It resists the tensile force generated at the lower edge of the beam member static moment (+ M) state, the concrete of the upper flange (100d) and the slab (100e) is to resist the compressive force generated at the upper edge.

In particular, the prestress compressive stress introduced into the lower flange concrete (100b) is introduced over the entire length of the prestressed steel-forming member 100, and thus the point portion of the continuous member 20 described above with respect to the parent portion (-M) section of the continuous member 20 The opposite direction of the stress generation form, and thus the existing pre-stressed steel composite member 100 synthesized only with the steel (I type Girder) and concrete is structurally impossible to design and manufacture as a continuous member (20).

The present invention provides a multi-span prestress steel composite continuous member and a method of hypothesis for designing a prestressed steel composite member that is designed and manufactured by a simple beam member as a continuous member as described above. The purpose is.

1 is an illustration of a three-span simple beam member that is repeated independently

2 is a cross-sectional stress diagram in the moment state of the simple beam member

3 is an illustration of a three span continuous member

4 is a cross-sectional stress diagram in the mid-moment section of the middle section of the continuous member.

5 is a cross-sectional stress diagram of the nominal section of the point of the continuous member

6 is a manufacturing schematic of the prestressed steel molding member,

(A) indicates the condition of the Ⅰ-shaped steel before loading

(B) shows the condition in which I-type steel is loaded in advance and the lower flange concrete is placed,

(C) shows the prestressed compressive stress introduced by removing the loaded load,

(D) shows the state where the upper flange, slab and abdominal concrete are poured.

7 is an illustration of the leafless steel composite member in which the secondary leafless compressive stress is introduced into the lower flange concrete through the tension member.

8 is an exemplary view of a four span prestressed rigid molded continuous member of the present invention.

9 is a hypothetical example of a four-span prestressed steel composite continuous member of the present invention

10 is a schematic diagram of a fabrication process for introducing a first prestressed compressive stress to the upper flange concrete of the point portion of the parent section section of the present invention,

(A) indicates the condition of the Ⅰ-shaped steel before loading

(B) placing the upper flange and the concrete of the abdomen by applying a load deformed upward;

(C) states that the primary prestressed compressive stress is introduced into the upper flange concrete by removing the load after curing the concrete.

(D) shows the state of the composite of the lower flange concrete.

11 is a front view of a state in which the tension member is pre-arranged in the upper flange concrete cross section of the point portion of the parent portion section member of the present invention

12 is a side view of the main part of FIG.

Figure 13 is a side view of a state in which the slab concrete is synthesized on the upper flange concrete after the construction of the point portion of the parent section section of the present invention

14 is a side view of the tension member under the upper flange of the I-shaped steel in the upper section of the concrete flange section, and the tension member on the upper flange of the I-shaped steel upper flange in the slab concrete section

15 is an exemplary view of the middle portion of the middle portion of the middle section of the present invention

16 is a coupling state diagram of each section member of the present invention

17 is an enlarged view of each section member connection portion of the present invention;

18 is a cross-sectional view taken along line 13 of FIG.

19 is a cross-sectional view B-B, C-C of FIG.

20 is a sectional view taken along the line D-D of FIG.

21 is a hypothetical flow chart of the continuous member of the present invention and the main portion side view

(A) is a condition of hypothesis section member

(B) is the hypothesis that the section moment of the moment is established

(C) shows the state in which the lower flange concrete is poured at the connection of each section member,

(D) is the correct state of tensioning the tension member after curing the concrete of the center slab and the upper flanges, slabs, abdomen, and fixing blocks at the point parent section.

(E) shows the state where the continuous member is completed by pouring and curing the upper flange, slab and abdominal concrete of the mid-moment section of the middle section.

* Description of symbols on the main parts of the drawings *

20: prestressed steel composite continuous member

21: constant moment section member

21a: I-shaped steel 21a ': Shear connection

21b: lower flange concrete 21c: abdominal concrete

21d: Upper Flange Concrete 21e: Slab Concrete

22: no point parent section section member

22a: I-shaped steel 22a ': transmission connection

22b: lower flange concrete 22c: abdominal concrete

22d: Upper Flange Concrete 22e: Slab Concrete

22f: settling block 23: support

24: temporary construction 25: tension member

25a: fixing device 212b: lower flange connection concrete

Hereinafter, with reference to the accompanying drawings, the specific content of the present invention for achieving the above object in more detail.

That is, according to the present invention, the prestressed compressive stress of the prestressed steel-molding member 100 can be independently resisted to the centers and branches of the continuous member 20 at the centers and branches of the continuous members 20. After being manufactured by separating it into the middle part of the middle moment section member 21 and the branch part of the parent moment section member 22 so as to be introduced, the temporary part of the moment section section 22 is first constructed and then the middle part of the section part of the moment section section ( 21) by incorporating prestressed compressive stress that allows the upper flange 22d and the slab 22e of the portion of the branched parent section section member 22 to be resisted to the section's parent section. Each section member 21, 22 is characterized in that it can be structurally continuous over the entire length.

In the above-described point portion of the parent moment section member 22, in order to resist the generated parent moment, in contrast to the central middle moment section member 21, compression prestress is not introduced into the lower flange concrete 22b at all. It is to resist only the compressive force of the lower edge, and to introduce the prestressed compressive stress to the upper flange (22d) and the slab concrete (22e) to resist the tensile stress generated by the parent moment.

On the other hand, the existing pre-stressed steel forming member 100 is a composite of only the I-shaped steel and concrete built up (I-shaped steel) or high-tensile steel sheet (Built-Up).

On the other hand, in the continuous member 20 according to the present invention, prestress compressive stress is applied to the upper flange 22d and the slab concrete 22e of each of the section members 21 and 22, in particular the branch parent section section member 22. Introduce.

That is, as shown in the tenth degree, the pre-stress compressive stress of the point portion of the parent section section 22 is different from the existing prestressed steel-molding member 100 by applying a positive load Pf 'to the I-shaped steel 101a and first rising accordingly. After the curing of the upper flange concrete (101d) and the abdominal concrete (101c) in the state that caused the deformation, the load (Pf ') is removed and the return deformation of the accompanying I-beam (101a) 1 by the upper flange concrete (101d) The primary prestressed compressive stress is introduced, and then the lower flange concrete 101b is inertia cured.

In the present invention, before placing the concrete in the upper flange concrete (22d) of the branch portion parent moment section member 22 by placing an appropriate amount of tension member 25 in advance and combined hypothesis with the inter-center middle moment section member 21 After the tension member 25 is tension-fixed, the secondary prestress compressive stress is further introduced.

In addition, the upper flange concrete 22d and the abdominal concrete 22c of the branch parent moment section member 22 have a predetermined length at both ends as shown in FIGS. 10 and 11 to form a coupling hypothesis with the middle mid section section member 21. ( 1) It will be manufactured in advance without the concrete composite.

As described above, the point portion non-cement section member 22 is introduced to the upper flange concrete 22d in the state where the first prestress compressive stress is introduced according to the introduction and removal of the load Pf 'causing the rising deformation of the I-shaped steel 22a. Length at both ends of 1) Only the central part except the part of the upper flange concrete (22d) and the abdominal concrete (22c) is combined hypothesis section point moment member 22 and the intermediary middle portion moment moment section member 21, the hypothesis On the pre-synthesized upper flange concrete 22d at the center of the cement section member 22, the slab concrete 22e is secondly cured.

The slab concrete 22e at the center portion of the parent portion section member 22 is a predetermined length for coupling hypothesis with the constant moment section member 21 at both ends of the member. 1) concrete where the upper flange concrete 22d and the abdominal concrete 22c are not synthesized, and the anchor block 22f which anchors the tension member 25 upon introduction of the secondary leafless compressive stress. Will be cured at the same time.

In particular, the tension member 25 of the point portion of the parent portion section may be arranged in the cross-section of the upper flange concrete (22d) pre-synthesized the total arrangement of all the parent portion section 22, depending on the conditions, such as design plan Some tension members 25 are fabricated by placing them in the cross-section of the upper flange concrete 22d immediately below the upper flange of the I-shaped steel 22a, and the tension member 25 on the upper flange of the I-shaped steel 22a has a positive moment in the middle of the trunk. After the coupling hypothesis with the section member 21 may be arranged in the slab concrete (22e) on the pre-synthesized upper flange concrete (22d).

According to the present invention, as shown in FIGS. 16 to 20, a predetermined length from the upper part of the abdominal portion 22c of the both ends of the parent moment section member 22 to the one end of the constant moment section member 21 ( 2) a tension block of the parent cement section member 22 by providing an anchor block 22f that protrudes and extends gradually below the abdomen 21c over a portion (the connecting portion of each of the fabricated and parent cement section members). 25 is distributed in the cross section of the fixing block 22f, and then the center slab concrete 22e of the parent section section 22, the abdominal concrete 22c, the upper flange concrete 22d, and the slab at both ends. At the same time, the concrete of the concrete 22e and the fixing block 22f is cast and cured, and the tension member 25 is tension-fixed at the connecting portion fixing block 22f through the tensioning equipment such as the hydraulic jack for tensioning and the fixing device 25a. The secondary leafless compressive stress is introduced into the concrete 22d and the slab concrete 22e.

Further, as shown in FIG. 13, the connection part fixing block 22f has a predetermined length including the shear connection parts 21a 'and 22a' of the inner I-beams 21a and 22a of the section members 21 and 22, respectively. ( 2) The front end portion 21a 'of the I-shaped steels 21a and 22a extends downwardly from the abdominal section 21c and 22c of the part so that the tension member 25 in the parent section is in the cross section of the fixing block 22f. (22a ') and gradually distributed downwards gradually downwards.

Therefore, in the present invention, when the secondary leafless compression stress is introduced into the upper flange 22d and the slab concrete 22e of the parent section section member 22, the shear section 22a 'is included. Combination of the (22) is more firm, and the cross-section of the mid-moment intercenter moment of the point portion where the total prestressed compressive stress introduced in the upper flange (22d) and lower flange concrete (22b) is generated in the continuous member (20) Crosses to fit naturally.

On the other hand, when manufacturing and constructing each section member 21 (22) of the prestressed steel composite continuous member 20 of the present invention as shown in the seventh degree, the constant moment section member 21 in the center portion of the trunk is a simple beam member state Designed and manufactured by a pre-stressed composite molding member 101 which greatly increases the prestressed compressive stress of the prestressed composite molding member 100 or the lower flange concrete 100b, Ensure consistent design, fabrication, and hypothesis processes are combined.

That is, the middle portion of the inter-zone constant moment section 21 introduces the prestressed compressive stress only to the lower flange concrete (21b), the introduction method is applied to the I-shaped steel (21a) as described above and caused accordingly After deflection deformation and concrete casting curing, the method based on the return deformation of the I-shaped steel (21a) after removing the load is used.

However, the above-mentioned leafless steel composite molding member 101 is particularly suitable for lowering the mold height of the member or introducing more prestressed compressive stress to the lower flange concrete 21b due to various other design and construction conditions. As shown in FIG. 2, the tension member 25 is also placed in the cross section of the lower flange concrete 21b in advance to apply a load to the I-shaped steel 21a to pour, cure, and lower the lower flange concrete 21b in a state where deflection deformation is caused. It is preferable to use a method of introducing the secondary leafless compressive stress by introducing the primary prestressed compressive stress due to the return deformation by removing the strain and then tension-fixing the tension member 25.

Meanwhile, the prestressed steel composite continuous member 20 of the present invention first hypothesizes the point portion of the parent portion section member 22 among the section members 21 and 22 independently manufactured for each section of the positive and parent sections, It is hypothesized by combining the constant moment section members 21. The connection point of each section member 21 and 22 is the intersection point of positive and parent moments in the generated moment diagram of the continuous member 20 (the magnitude of the generated moment is 0 Prestressed compressive stress introduced into the upper flange 22d of the point portion parent moment section member 22 and the slab concrete 22e and the lower flange concrete 21b of the middle mid section section member 21 between the middle portion and the middle point section. It naturally coincides with the intersection of the prestressed compressive stress introduced in

In the above, the fixing block 22f of the intersection point passes through the shear connection portions of the section members 21 and 22 at the same time, and at the same time, the lower flange concrete 21b of the constant moment section member 21 into which the prestress compressive stress is introduced is constant. Length( 3) the tension member 25 of the parental section member 22 distributed in the cross section of the fixing block 22f is gradually extended downward so as to gradually protrude and extend downward to the overlapped position. And a constant length while approaching the lower flange concrete 21b of the constant moment section member 21 ( 3) Secondary leafless compressive stress static moment introduced into the upper flange concrete 22d and slab concrete 22e in the parent section by tension-fixing the tension member 25, which is overlapped by 3), at the end of the fixing block 22f. The total prestressed compressive stress introduced into the lower flange concrete 21b of the section is a certain length of the end point of the fixing block 22f ( 3) It is possible to have a continuous prestressed compressive stress structure that overlaps in parts and crosses in opposite directions.

Therefore, the continuous member 20 of the present invention is naturally coinciding with the positive point, the parent point intersection point and the shape of each interval ( ) Is a continuous prestressed cross-stress structure that is continuously connected repeatedly.

Next, the fabrication and construction method of the prestressed steel composite continuous member 20 of the present invention will be described in detail by the process sequence shown in FIG.

1) Fabrication and Hypothesis of Branch Parental Section Member ~ Fig. 21 (A)

(1) Manufacture of Ⅰ-shaped steel ~ Ⅰ-shaped steel (22a) is centered on the abdominal (22c) at both ends to be a staggered connection for shear connection by means of welding or bolts It is manufactured to have a shear connection portion 22a 'of a suitable length at the bottom.

(2) Loading deformation of I-beams and casting of upper flanges and abdominal concrete-Loads that induce upward bending deformation in the I-beams 22a produced as opposed to the conventional prestressed steel composite molding (100). (Pf ') and a certain length for shear connection with the middle section 1) The upper flange concrete 22d and the abdominal concrete 22c are synthesized in the center except for the portion.

In the above-mentioned upper flange concrete part 22d, a proper amount of tension member 25 is introduced in advance in order to introduce a secondary leafless compressive stress, and the tension member 25 is composed of the upper flange concrete member 22d at the center of the member. ) Continued to extend toward both ends of the member in the cross-section to be distributed and distributed to the fixing block 22f after the coupling hypothesis with the middle portion of the middle portion constant moment section 21.

In particular, the tension member 25 may be arranged in the cross-section of the upper flange concrete 22d, which is pre-synthesized the entire layout, and some tension members 25 are the upper flange of the I-shaped steel (22a) according to the conditions, such as design plan It may be arranged in advance in the cross section of the concrete 22 immediately below, and placed in the slab concrete 22e part after the construction hypothesis with the constant moment section member 21 between the middle section.

(3) Removal of introduction load (Pf ') and introduction of primary prestressed compressive stress to upper flange concrete ~ Load applied to I-shaped steel (22a) when curing of upper flange concrete (22d) and abdominal concrete (22c) is completed Pf 'is removed to introduce the first prestress compressive stress into the upper flange concrete 22d.

(4) Placement of lower flange concrete, curing ~ The upper flange concrete 22d has a primary prestressed compressive stress introduced with the abdominal concrete 22c in the state where the composite material of the I-shaped steel 22a of the lower flange portion of the concrete In this case, the lower flange concrete (22b) in the lower flange concrete (22b) as the point portion of the parent section section 22, without introducing the prestress stress to resist only the compressive force generated at the lower edge of the continuous member 20, the middle section constant moment section member 21 In order to be connected to the I-shaped steel (22a) of the (1), the concrete is not synthesized in the shear connection portion (22a ') located at both ends.

(5) Hypothesis-concrete curing is completed, the point portion of the parent section section 22 is installed by a crane, etc. in the correct position on the point support 23 (stool device) to be fixed with the support 23, welding, bolts and the like. . At this time, the branch portion parent moment section member 22 supports the center of gravity centering around the support 23, and the point portion to support the hypothesis weight up to just before the complete connection with the middle section of the middle moment section 21 Temporary structures 24 (temporary bridges) are installed in advance at both sides of the connection portion, or in the vicinity thereof, so that two temporary structures 24 and the support 23 are placed.

2) Fabrication and Hypothesis of the Static Moment Section Member in the Central Section ~ Fig. 21 (B)

(1) Manufacture of I-shaped steel ~ I-shaped steel 21a of the mid-center static moment section member 21 is made of I-shaped steel of two point section non-mental section members 22, both sides of which are prefabricated and constructed Of the (22a) one side end of the lower shear connecting portion (22a ') to be placed on the support hypothesis in the state to be connected to the connecting portion, for this purpose, both sides of the I-shaped steel (21a) of the section middle moment moment member 21 of the middle section The end portion is provided with a predetermined length of the shear connection portion 21a 'on the upper side thereof so as to be engaged with the lower shear connection portion 22a' at both ends of the I-shaped steel material 22a of the parent cement section member 22.

(2) Introducing casting curing of lower flange concrete and introduction of prestress or leafless compressive stress ~ I-shaped steel (21a) by introducing a load (Pf'load) to generate a constant moment of bending moment into the manufactured I-shaped steel (21a). In the state where the deflection deformation is caused to be bent downward, the lower flange concrete 21b is poured and then the load is removed to introduce the prestressed compressive stress according to the return of the deflection deformation.

In order to introduce a larger prestressed compressive stress in the above, before placing concrete in the lower flange concrete 21b cross section, the tension member 25 is placed in advance to introduce the first prestressed compressive stress due to load introduction and removal, and then the tension member again. Tensile settling at (25) introduces a second releasant compressive stress.

(3) Hypothesis-produced middle middle portion constant moment section member 21 is the I-shaped steel member 22a of the parent section section member 22 in the center of the two point portion parent moment section member 22, which has been hypothesized in advance. The upper shear connecting portion 21a 'on both sides of the I-shaped steel member 21a of the constant moment section member 21 is placed on the lower shear connecting portion 22a', and it is hypothesized by a crane or the like.

3) Joint connection of type I steel at the connection part and casting of the lower flange concrete at the connection part, curing ~ Fig. 21 (C)

Each of the positive and non-mental section members (21) and (22), which are fabricated independently of each other, is engaged with the shear connecting portions (21a ') and (22a') of the I-shaped steels (21a) and (22a), and welds the interlocked portions. The section members 21 and 22 are connected to each other by fastening with bolts.

And the lower flange concrete (212b) of the connecting portion of each section member (21) 22, which did not cast concrete for the connection is poured and cured, I-shaped steel (21a) (22a) and lower flange concrete (21b) Each of the composite elements in (22b) has a continuous structure throughout the entire section.

4) Placement of tension in the center section slab concrete section of the branch section non-mental section member, and extension and rearrangement of the extension material of both ends and the tension block in the fixing block. Slab concrete on upper flange concrete 22d in the center of the member, if previously designed to be arranged in the section of the tension member 25 slab concrete 22e on the upper flange of I-shaped steel 22a in the non-cement section member 22 (22e) The tension member 25 in the cross section is extended to the end of the fixing block 22f, and the tension member 25 in the cross section of the concrete 22d immediately below the upper flange of the pre-arranged I-shaped steel 22a is also extended. The upper flange portion and the fixing block 22f, which are not pre-synthesized at both end portions of the member, are extended and distributed at the same time.

In addition, even if the total planned tension members 25 are all previously arranged in the upper flange concrete 22d cross section, all of the extension portions are extended to the uncomposited upper flange 22d cross section and the fixing block 22f at both ends of the member as described above. To be distributed.

In addition to the arrangement of the tension member 25 as well as the reinforcement and formwork assembly of the slab portion of the center portion of the branch portion parent section section 22 and the non-synthesized upper flange and the slab, the abdomen, and the fixing block of both ends .

As described above, the fixing block 22f has a predetermined length (m) at the abdominal portions 21c and 22c of the front end connecting portion of each section member 21 and 22, as described above. 2) while extending downward gradually over a certain length with the lower flange concrete (21b) of the constant moment section ( 3) The end point is positioned at the overlapping position by 3), and the tension member 25 gradually includes the shear connection portions 21a 'and 22a' of the I-shaped steels 21a and 22a in the fixing block 22f. The lower flange concrete 21b of the constant moment section and a certain length ( 3) arranged so as to be overlapped so as to have a continuous prestressed compressive stress structure that naturally matches the positive, non-intersecting points and shapes of the continuous member 20.

5) Branch parent section The slab concrete at the center of the section member and the upper flanges at both ends, and the concrete casting and curing of the slabs, abdomen, and fixing blocks. The slab concrete 22e at the center of the section section member 22, the both ends of the abdomen 22c, and the concrete such as the upper flange 22d and the slab 22e and the fixing block 22f are successively cured.

In particular, the abdominal portion 21c, the upper flange 21d, and the slab concrete 21e of the middle portion of the inter-center static moment section 21 are loads that generate their own momentum in the point portion. 22) Concretes such as the center slab concrete 22e, the abdomen 22c at both ends, the upper flange 22d, the slab 22e and the fixing block 22f are first cured, and the overall design load (including live loads) on the concrete. ) Or, after introducing a secondary leafless compressive stress of a size that can only resist composite self-weight (total dead weight including concrete, such as slabs and upper flanges in the mid-moment of the mid-center region), The upper flange concrete 21d, the slab concrete 21e, and the abdominal concrete 21c of 21 are poured and cured.

Accordingly, the slab 22e at the center of the parent section section 22 and the upper flange 22d and the slab 22e and the abdomen 22c at the center of the parent section section member 22 of the total length of the continuous member 20 and the middle section of the trunk. Since the upper flange 21d, the slab 21e, and the abdomen 21c of the constant moment section are separately cast to cure the concrete, the boundary of the separate cast section of the concrete does not generate any tensile stress at the top of the member. (Including live load) Make sure that the bending stress at the time of action is the point of compression of very small size.

In other words, the upper flange 21d (22d) and the slab (21e) (22e) and the abdominal concrete (21c) (22c) is divided into separate sections of the middle mid-moment section and the point parent section, respectively, the boundary of the pouring section The small moment is a state of the small moment, and the both ends of the middle portion of the center portion constant moment section 21, which is near the completion point of the fixing block (22f) including the connection point overlaps to include a predetermined period.

6) Introduction of Stop-Resistless Compression Stress to Branch Flanges Section Members Upper Flange and Slab Concrete ~ Fig. 21 (D) ~ Abdominal Section Slabs 22e and Both Ends 22c, the upper flange 22d and the slab 22e, the fixing block 22f, the curing of the concrete placed in succession is finished when the tensioning member 25 is placed in the fixing block 22f and then fixed It is fixed by the device 25a to introduce the secondary represtressed compressive stress. Design active load considering the secondary concrete such as the abdomen 21c, the upper flange 21d, and the slab 21e in the middle moment of the middle section is not poured (the whole design dead weight is not loaded). Point part generated by only the total designer's weight (dead load), including the abdomen 21c and the secondary flange, such as the upper flange 21d and the slab 21e, in the middle moment of the middle section First, only the prestressed compressive stress that can resist the size of the parent moment is introduced first, and then the secondary member such as the abdominal 21c, the upper flange 21d, and the slab 21e in the middle section of the middle section is cast and cured. (20) The total prestressed compressive stress, which is the final design target value, is to be introduced from the full-scale design load to the full design load including live load.

In addition, the weight of secondary cast concrete such as the abdomen 21c and the upper flange 21d and the slab 21e in the mid-center region of the inter-center region did not have a significant effect on the overall design parent size of the site. Prestress compression up to the total design load, including live load, even when secondary concrete such as the abdomen 21c, the upper flange 21d, and the slab 21e is not placed (the entire designers of the continuous member bulbs are not loaded). If the stress is first introduced and then predesigned to cast the secondary concrete in the mid-center, the total prestressed compressive stress up to the final design target value is introduced sequentially.

7) Secondary concrete placing curing of upper flange, slab, abdomen, etc. in the middle section of the middle section of the trunk-Fig. 21 (E)-Upper flange 22d, slab 22e and abdomen 22c In the state where the secondary concrete of the back is poured and cured, the upper flange 21d, the slab 21e, the abdomen 21c, etc., which are the secondary concrete portions of the middle portion of each of the middle sections already bounded by the partition, are successively poured.

8) Completion of the overall structural system of prestressed steel composite continuous members and construction of temporary structures (introduction of prestressed compressive stress to upper flange concrete (22d) and slab concrete (22e) and the center of the middle section When the curing of secondary poured concrete such as the abdomen 21c, the upper flange 21d and the slab 21e is finished in the cement section, the entire structural system of the prestressed steel composite continuous member 20 is completed.

Therefore, the temporary structure, which was installed at each connection part of each section member 21 and 22, to support the hypothesis weight of each section member 21 and 22 until the entire structural system of the prestressed steel composite continuous member 20 was completed. 24) dismantle and dismantle.

As described above, the present invention can be manufactured and hypothesized by using a prestressed steel composite member or a leafless steel composite member as a continuous member whose design maximum bending moment is reduced to be resisted under constant intervals and reload conditions. According to the present invention, by reducing the design maximum bending moment compared to the simple beam member 10 of the same conditions, it is possible to significantly reduce the cross-section, mold height, the amount of use of the material, its own weight, etc., one for each point It is possible to install a continuous member easily by using only the support 23 of course, and it is not necessary to install a separate expansion joint in the middle. Not only will it significantly reduce manpower consumption and work costs, but it will also increase the safety of the bridge. Effects such as being able to shorten the air can be obtained.

Claims (12)

The prestressed steel composite member, which is a composite of I-shaped steel and concrete, or a leafless steel composite member, which is a composite of tensile material, is formed in the steel composite member. Each section member (21) and (22) are manufactured by separating and separating into the center middle moment section member 21 and the branch parent section section member 22 so that prestress compression stresses of a form that can be independently resisted are introduced. And a prestressed compressive stress for resisting the static moment of the section to the lower flange concrete 21b of the intercenter central moment section member 21, while The prestressed compressive stress that allows the upper flange 22d and the slab concrete 22e of the Member 21, 22 is the span prestressed composite continuous steel member characterized in that so as to be structured as continuous over the entire length. The method according to claim 1, wherein the point portion of the parent cement section member 22 does not introduce any compression prestress to the lower flange concrete 22b in order to resist the generated parent moment, only the upper flange 22d and the slab concrete 22e A multi-span prestressed steel composite continuous member characterized by introducing a prestressed compressive stress. The method of claim 1, wherein the load (Pf ') is bent upwardly deformed to the I-shaped steel (22a) of the point portion of the parent section section member 22, and after pouring the upper flange concrete (22d) to remove the load Multi-span prestressed steel composite continuous member, characterized in that the pre-stressed compressive stress is introduced into the upper flange concrete (22d). The method according to claim 1, before placing the upper flange 22d and the slab concrete 22e concrete in the cross-section of the parent portion section member 22, the appropriate amount of the tension member 25 is placed in advance and the point as the tension member 25 Multi-span prestressed steel composite continuous member, characterized in that the pre-stressed compressive stress is introduced into the upper flange concrete (22d) and the slab concrete (22e) of the secondary parent section section member (22). The tension member according to any one of claims 1, 3, and 4, wherein a load Pf 'for causing upward bending deformation is applied to the I-shaped steel material 22a, and an appropriate amount of tension member in the cross section of the upper flange concrete 22d is previously applied. (25) is placed and cured the upper flange concrete (22d), and then remove the load (Pf '), the point portion of the parent section section produced with the primary prestress compression stress introduced to the upper flange concrete (22d) (22) and the hypothesis combined with the constant moment section member 21 in the middle section, and then tension-fixed the tension member (25) disposed in the upper flange concrete (22d) of the parent section section of the point portion to introduce the secondary prestress compression stress Multi-span prestressed steel composite continuous member characterized in that. The upper flange concrete 22d having prestressed compressive stress due to deformation of the I-shaped steel 22a, and the lower flange concrete 22b having no prestressed compressive stress, The upper flange concrete portion 22d of the branch portion moment moment section member 22 after the temporary portion of the moment portion section member 22 in which the abdominal concrete 22c is synthesized is combined and hypothesized A multi-span prestressed steel composite continuous member, characterized in that the slab concrete (22e) is poured on the cured. The center portion constant moment section member 21 according to claim 5, wherein the point portion parent moment section member 22 in which the tension member 25 for introducing the secondary leafless compressive stress is appropriately disposed in the cross-section of the upper flange concrete 22d. After the hypothesis of the coupling with the appropriate amount of tension member 25 in the cross-section of the slab concrete 22e on the pre-synthesized upper flange concrete (22d) and the tension of the tension member 25, the upper flange concrete of the point portion of the cement section ( 22d) and a multi-span prestressed continuous member characterized by introducing a secondary leafless compressive stress into the slab concrete (22e). The tension member (25) according to any one of claims 4, 5, 6, and 7, wherein the tension member (25) is formed from the upper part of the abdominal portion (22c) of both ends of the parent section section member (22). A certain length including the shear connecting portions 21a 'and 22a' of the I-shaped steels 21a and 22a of the connecting portion ( 2) the center slab concrete 22e of the parent moment section member 22 after dispersing and disposed in the cross section of the fixing block 22f that protrudes and extends below the abdominal section 21c of the constant moment section member 21, The upper flange concrete 22d, the slab concrete 22e, the abdominal concrete 22c, and the concrete of the fixing block 22f are cast and cured at the same time, and fixedly fixed to the fixing block 22f as the fixing device 25a. Multi-span prestressed steel composite continuous member, characterized in that. The fixing block 22f has a predetermined length and a lower flange concrete 21b of the constant moment section member 21 into which the prestress compression stress is introduced. 3) The tension member 25 distributed in its cross section gradually extends downward to a position overlapped by the overlapping portion, and gradually extends toward the lower portion and gradually approaches the lower flange concrete 21b of the constant moment section, while maintaining a constant length ( 3) Multi-span prestressed steel composite continuous member, characterized in that overlapping as much as. The multi-span prestress of claim 1, wherein the constant moment section member 21 of the center portion is designed and manufactured as a leafless steel composite member 101 which increases the prestress compression stress of the lower flange concrete 100b. Steel composite continuous member. The upper flange 22d and the slab concrete 22e of the point portion of the parent cement section member 22 are formed at the intersection of the positive and the parent moments, and the connection point of each section member 21 and 22 is set at the intersection thereof. A multi-span prestressed steel composite continuous member, characterized in that it is naturally matched with the intersection of the pre-stress compression stress introduced into the center portion and the pre-stress compression stress introduced into the lower flange concrete (21b) of the mid-center static moment section member (21). Independently resists static and parental moments when constructing continuous members for two or more spans of prestressed steel composite material that combines section steel and concrete or leafless steel composite material that combines tension material into prestressed steel composite member. After constructing a plurality of point portion parent moment section members 22, the intersecting section middle moment moment member 21 is interposed between the point portion parent section section members 22, and the I-shaped steel member 22a. Constant length at both ends of the The lower flange concrete 22b and the abdominal concrete 22c in which the primary prestress compressive stress due to the deformation of the I-shaped steel 22a is introduced into the central upper flange concrete 22d except for 1), and the prestress compressive stress is not introduced. Is constructed by combining the point portion parent moment section member 22, and the intercenter central moment moment section member 21 in which the prestressed compressive stress is introduced only to the lower flange concrete 21b of the I-shaped steel 21a. The slab concrete 22e and the concrete of the fixing block 22f on the first synthesized upper flange concrete 22d in the cement section are cast and cured at the same time, and then the tension member 25 previously placed in the cross section is fixed and fixed. A multi-span bridge characterized by introducing a prestressed compressive stress and placing and curing the upper flange concrete (21d) and the slab concrete (21e) of the middle portion of the inter-zone static moment section. Hypothesis method of wristless steel composite continuous member.