JP4992042B2 - Precast horizontal beam and pier using it - Google Patents

Description

  The present invention relates to a precast lateral beam used for a viaduct and a pier using the same.

  As for viaducts, there are T-type piers that are T-shaped with pier columns and cross-beams, L-type piers that are reverse L-shaped with pier columns and cross-beams, and ramen piers with ramen structures. Is used.

  And as the construction structure, both the pier column and the pier side beam are reinforced concrete piers made of reinforced concrete (for example, Patent Document 1), and the steel pier that the pier column and the pier side beams are both made of steel (for example, Patent Documents). 2).

FIG. 17 shows a reinforced concrete pier (T-type pier) described in Patent Document 1. In order to shorten the construction period, in the joint structure between the column 81 and the beam 91 of the reinforced concrete pier, an insertion body 83 having a protrusion on the inner surface is provided at the joint portion of the column 81 with the beam 91. 91 is provided with an insertion body 95 having a protrusion on the outer surface that can be inserted into the insertion hole 83, and the insertion body 95 is inserted into the insertion hole 83 to fill a gap between the insertion hole 83 and the insertion body 95. A column and a beam are joined by injecting a material.
JP 2002-146720 A JP-A-63-176504

  However, conventional reinforced concrete piers and steel piers have the following problems.

  First, in the conventional reinforced concrete pier structure, the column part is made of reinforced concrete made in the field, so it takes construction time and cannot cope with rapid construction. In addition, since the horizontal beam portion is a top heavy with a massive structure, the horizontal load acting on the base of the pier column becomes large during an earthquake, and the cross section of the pier column becomes relatively large. Furthermore, piers made of reinforced concrete have a high weight and not only increase the force applied to the foundation pile, but also cannot be used on soft ground. Moreover, in the case of a reinforced concrete pier, a massive footing is required for the foundation structure, so the construction area is widened. As a result, the construction cost is high, the construction speed is slow, and the land acquisition area is large.

  Next, in the conventional steel pier structure, the fatigue resistance of the corner portion between the pier horizontal beam portion and the pier column portion is low. Moreover, since the degree of processing is high, the manufacturing cost is high. Further, when the bolt contact portion is provided, not only the beauty is impaired, but also the deterioration of the coating is accelerated, so that the maintenance and management are inferior.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a bridge pier (T-type pier, L-type pier, ramen pier) having an economical structure excellent in workability and durability. It is what.

  In order to solve the above problems, the present invention has the following features.

[1] A precast cross beam manufactured in a factory in advance for use as a cross beam for a pier,
Using a steel pipe in which a plurality of cuts are made at the upper end, a stopper is installed on the outer periphery near the lower end or near the lower end, and a T-shaped steel whose web height is the same as or shorter than the cut length of the upper end of the steel pipe,
A precast cross beam comprising: a web portion of the T-shaped steel inserted into a cut portion at an upper end of the steel pipe, and a steel pipe upper end cut portion and a T-shaped steel web portion being welded.

  [2] The precast cross beam according to [1], wherein an upper end of the steel pipe and a flange portion of the T-shaped steel are welded.

  [3] A concrete placement hole is formed above the steel pipe, a slip stopper is installed on the outer peripheral surface near the lower end of the steel pipe or near the lower end, and the concrete is filled into the steel pipe from the placement hole to a predetermined height. The precast lateral beam according to [1] or [2].

  [4] The precast lateral beam according to any one of [1] to [3], wherein the T-shaped steel is covered with reinforced concrete.

  [5] The precast cross beam according to [4], wherein a slip stopper is installed on a contact surface of the T-shaped steel and the steel pipe with the concrete.

  [6] For a portion of the T-shaped steel that protrudes from the steel pipe, a lower flange is welded to the T-shaped steel, or a lower flange that fits inside the steel pipe is removed instead of the T-shaped steel. The precast cross beam according to any one of [1] to [5], wherein a portion protruding from the steel pipe is formed into an H-shaped steel material by using the H-shaped steel.

  [7] The precast transverse beam according to any one of [1] to [5], wherein a π-shaped steel is used instead of the T-shaped steel.

[8] A pier using the precast horizontal beam according to any one of [1] to [7] as a pier horizontal beam,
A steel pipe pier column with a stopper installed on the inner peripheral surface near the upper end or near the upper end is constructed, and the steel pipe portion of the precast horizontal beam is inserted into the steel pipe pier column, and concrete is placed in the gap between the steel pipe pier column and the steel pipe portion. A pier characterized by joining by filling.

  [9] After installing a projection on the inner peripheral surface of a predetermined height from the upper end of the steel pipe pier column, and dropping the circular mold on the projection, the circular mold is installed in a diaphragm shape, Concrete is cast into the steel pipe pier column from the gap at the upper end of the steel pipe pier column or the hole previously opened in the precast horizontal beam with the lower surface of the steel pipe part of the precast horizontal beam in contact with the circular formwork. The bridge pier according to [8] above, wherein

  [10] The bridge pier according to [8] or [9], wherein a spiral steel pipe is used for the steel pipe pier column.

  [11] After constructing a steel pipe pile in which at least the pile head has a diameter larger than the diameter of the steel pipe pier column and the stopper is installed on the upper end portion or the inner peripheral surface near the upper end, the lower end of the steel pipe pier column Alternatively, a stopper is installed on the outer peripheral surface in the vicinity of the lower end, the steel pipe bridge pier column is inserted into the steel pipe pile, and the steel pipe bridge pier column and the steel pipe pile are joined by filling with concrete. The pier according to any one of 8] to [10].

  [12] A protrusion is installed on the inner peripheral surface of a predetermined height from the upper end of the steel pipe pile, and the circular mold is placed in a diaphragm shape by dropping the circular mold on the protrusion. With the pier column inserted into the steel pipe pile and the bottom surface of the steel pipe pier column in contact with the circular formwork, the gap between the steel pipe pier column and the steel pipe pile is filled with concrete, and the concrete is put inside the pier column in the same section. The pier according to [11], wherein the pier is filled.

  In the above, the form of the pier includes a T-type pier, an L-type pier, and a ramen pier. In addition, the precast cross beam means a cross beam manufactured in advance at a factory or the like, and includes not only concrete but also steel.

  According to the present invention, a bridge pier that is economical and excellent in workability and durability can be obtained.

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

  FIG. 1 shows a pier (here, a T-type pier) P and its peripheral members according to an embodiment of the present invention. The T-type pier P according to this embodiment includes a pier side beam portion P1 made of a precast cross beam manufactured in advance in a factory, a pier column portion P2 using a spiral steel pipe, and a pier foundation portion made of a steel pipe pile S. Yes. And the bridge pier horizontal beam part P1 and the pier column part P2 are joined by the double pipe socket part W1, and the pier pillar part P2 and the pier base part S are joined by the double pipe socket part W2. In FIG. 1, D is a floor slab, B is a girder, and C is a gutter.

  And this T type bridge pier P is constructed by the following construction procedures.

  First, a precast cross beam P1 is manufactured in advance at the factory in the following procedures (S1) to (S4).

  (S1) As shown in FIG. 2, a plurality of cuts 3 having the same length are made at the upper end of the steel pipe 1, a concrete placement hole 8 is opened at the upper part of the steel pipe 1, and the lower end of the steel pipe 1 or the outer peripheral surface near the lower end is formed. The stopper 4a is installed. The web portion 2b of a T-shaped steel (rolled T-shaped steel, welded T-shaped steel, cut T-shaped steel) 2 having a web height that is the same length as or shorter than the notch 3 at the upper end of the steel pipe 1 is used as a steel pipe. 1 Insert into the notch 3 at the top.

  (S2) Next, as shown in FIG. 3, the notch part 3 of the steel pipe 1 and the web part 2b of the T-section steel 2 are welded. At that time, in order to avoid stress concentration, only the straight portion of the cut portion 3 and the web portion 2b are welded. In addition, the upper end of the steel pipe 1 and the flange part 2a of the T-shaped steel 2 are welded as needed.

  (S3) Next, as shown in FIG. 4, the concrete 6 is filled into the steel pipe 1 from the concrete placement hole 8 in the upper part of the steel pipe 1 to a predetermined height (for example, the position of the concrete placement hole 8).

  (S4) Then, as shown in FIG. 5, the T-shaped steel 2 is covered with the reinforced concrete 5. At that time, it is preferable to install a stopper in advance on the contact surface of the steel pipe 1 and the T-shaped steel 2 with the concrete.

  Next, at the construction site, a T-type pier is constructed according to the following procedures (S5) to (S9).

  (S5) As shown in FIG. 6, at least the pile head has a diameter larger than the diameter of the steel pipe pier column P2, and the stopper 24b is installed on the upper end portion or the inner peripheral surface in the vicinity of the upper end, The steel pipe pile S in which the protrusions 29 are installed on the inner peripheral surface of the height of is constructed. Then, after dropping the circular mold 27 onto the protrusion 29, the circular mold 27 is installed in a diaphragm shape, and the stopper 14b is installed on the outer peripheral surface near the lower end or the lower end, and at a predetermined height from the upper end. With the steel pipe pier column P2 having the projections 19 installed on the inner peripheral surface inserted into the steel pipe pile S, the steel pipe pier column P2 and the steel pipe pile are in contact with the lower surface of the steel pipe pier column P2 on the circular formwork 27. The concrete 26 is filled into the gap with S, and the concrete 26 is filled into the steel pipe pier column P2 in the same section. Thereby, the steel pipe pier column P2 and the steel pipe pile S are joined by the double pipe socket structure.

  (S6) Next, as shown in FIG. 7, the circular mold 17 is installed in the form of a diaphragm by dropping the circular mold 17 on the protrusion 19 on the inner peripheral surface of the steel pipe pier column P2, and then manufactured at the factory. The steel pipe portion 1 of the precast cross beam P1 is inserted into the steel pipe pier column P2.

  (S7) Then, as shown in FIG. 8, the lower surface of the steel pipe portion 1 of the precast transverse beam P1 is brought into contact with the circular formwork 17.

  (S8) Then, as shown in FIG. 9, the concrete 16 is inserted into the gap between the steel pipe pier column P2 and the steel pipe 1 from the gap at the upper end of the steel pipe pier column P2 or the hole (not shown) previously formed in the precast horizontal beam P1. Fill. Thereby, the precast cross beam P1 and the steel pipe pier column P2 are joined with a double pipe socket structure.

  (S9) Thereby, a T-type pier as shown in FIG. 10 is constructed.

  And the following effects can be acquired by constructing a T-type pier as mentioned above.

  (1) Steel pipes are used for the pier columns, precast materials are used for the bridge piers, and a double pipe socket system is used for these joints, eliminating the need for on-site welding and making it difficult for weld defects to occur. Therefore, the structure has excellent fatigue resistance.

  (2) In addition, since the shape steel is used as much as possible, the processing cost is low.

  (3) Furthermore, since the pier column part and the pier side beam part are separately constructed, the member maximum weight is small, and the transportability of the member and the function of construction are high.

(4) In addition, the pier cross beam part is steel with excellent tensile resistance at the top (T-shaped steel flange), concrete with excellent compression resistance at the bottom, and concrete-coated steel with excellent shear resistance at the center of the cross section (T-shaped steel web) is positioned, and since it is a reasonable combination, it is economical.
That is, as shown in FIG. 11 (a), the life-and-death load from the bridge superstructure acts on the pier horizontal beam portion P1, so that the bending moment and shear force are applied to the pier horizontal beam portion P1 as shown in FIG. 11 (b). As shown in FIG. 11C, a tensile force acts on the upper cross section of the pier horizontal beam portion P1, a compressive force acts on the lower cross section of the pier horizontal beam portion P1, and a shear force acts on the entire cross section. However, the flange 2a of T-shaped steel resists the tensile force at the top of the cross section of the pier horizontal beam portion P1, and the concrete 5 resists the compressive force at the bottom of the cross section of the pier horizontal beam portion P1. The T-shaped steel web 2b resists the shearing force.

  (5) As a result of the above (1) to (4), the construction cost can be reduced.

  (6) Furthermore, since a double pipe socket structure is adopted for the joint between the steel pipe pile and the pier column and the joint between the pier column and the pier cross beam, the construction error of the steel pipe pile is reduced between the two joints. Can be absorbed by eccentric bonding.

(7) Moreover, because the double pipe socket structure in which the inner pipe and the outer pipe of the double pipe are both round steel pipes is adopted and the inside of the inner pipe is filled with concrete, the inner pipe and the outer pipe The binding force to the filled concrete in between can be secured and can be firmly bonded.
That is, as shown in FIG. 12, in the double pipe socket part W1, the outer peripheral surface detent 4a and the outer pipe (pier pier column P2) of the inner pipe (steel pipe 1) are applied regardless of whether tensile force or compressive force is applied. ) Of the filled concrete 6 compresses and resists against the inner peripheral surface displacement stopper 14b. Similarly, in the double pipe socket portion W2, the outer peripheral surface detent 14a of the inner pipe (pier pier column P2) and the inner circumference of the outer pipe (steel pipe pile S), regardless of whether tensile force or compressive force is applied. The filled concrete 16 is compression-resistant between the surface displacement stoppers 24b.

  (8) Furthermore, since all of the foundation pile, the pier column and the cross beam of the pier are precast members (members manufactured in advance at the factory), the work at the construction site is shortened, and rapid construction can be handled.

  In the above, when the precast cross beam P1 is manufactured, the lower flange is welded to the T-section steel 2 with respect to the portion of the T-section steel 2 that protrudes from the steel pipe 1, or as shown in FIG. Instead of steel 2, an H-shaped steel (rolled H-shaped steel, welded H-shaped steel) 31 is used, and by removing the lower flange where it fits inside the steel pipe 1, the portion that protrudes from the steel pipe 1 has an H-shape. You may make it become steel materials. Thereby, the rigidity of the precast cross beam P1 can be increased.

  Further, when the precast cross beam P1 is manufactured, as shown in FIG. 14, a π-shaped steel (welded shaped steel having a π-shaped cross section) can be used instead of the T-shaped steel 2. When the acting load is large and a single web such as the T-section steel 2 cannot resist the cutting force, a π-section steel having two webs is effective.

  In the above embodiment, the T-type pier has been described. However, by taking the same construction procedure as that shown in FIG. 15, an L-type pier is constructed as shown in FIG. It can also be built.

It is a figure showing a T type pier and peripheral members concerning one embodiment of the present invention. It is a figure which shows construction procedure S1 of the T-type pier concerning one Embodiment of this invention. It is a figure which shows construction procedure S2 of the T type pier concerning one Embodiment of this invention. It is a figure which shows construction procedure S3 of the T-type pier concerning one Embodiment of this invention. It is a figure which shows construction procedure S4 of the T-shaped pier concerning one Embodiment of this invention. It is a figure which shows construction procedure S5 of the T type pier concerning one Embodiment of this invention. It is a figure which shows construction procedure S6 of the T-type pier concerning one Embodiment of this invention. It is a figure which shows construction procedure S7 of the T type bridge pier which concerns on one Embodiment of this invention. It is a figure which shows construction procedure S8 of the T type pier concerning one Embodiment of this invention. It is a figure which shows construction procedure S9 of the T type bridge pier which concerns on one Embodiment of this invention. It is a figure which shows the force generate | occur | produced in the T-type pier concerning one Embodiment of this invention. It is a figure which shows the flow of the force in a double tube socket part. It is a figure which shows the T-type pier which concerns on other embodiment of this invention. It is a figure which shows the T-type pier which concerns on other embodiment of this invention. It is a figure which shows the L-shaped pier which concerns on other embodiment of this invention. It is a figure which shows the ramen bridge pier which concerns on other embodiment of this invention. It is explanatory drawing of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Steel pipe 2 T-shaped steel 2a T-shaped steel flange 2b T-shaped steel web 3 Notch 4a Outer surface displacement prevention of steel pipe 5 Reinforced concrete 6 Filled concrete 8 Concrete placement hole 14a Outer surface displacement prevention of steel pipe bridge pier column 14b Inside of steel pipe pier column Peripheral surface stopper 16 Filled concrete 17 Circular formwork for transverse beam part temporary support 19 Protrusion on the inner surface of steel pipe pier pillar 24b Inner peripheral face prevention of steel pipe pile 26 Filled concrete 27 Circular formwork for temporary support part of bridge pier part 29 Steel pipe pile Projection on the inner surface 31 H-section steel 41 π-section steel B Girder C Ｄ D Floor slab P Bridge pier P1 Bridge pier side beam (precast cross beam)
P2 Pier column S Steel pipe pile W1 Double pipe socket part W2 Double pipe socket part

Claims (12)

It is a precast cross beam manufactured in the factory in advance for use as a cross beam for a pier,
Using a steel pipe in which a plurality of cuts are made at the upper end, a stopper is installed on the outer periphery near the lower end or near the lower end, and a T-shaped steel whose web height is the same as or shorter than the cut length of the upper end of the steel pipe,
A precast cross beam comprising: a web portion of the T-shaped steel inserted into a cut portion at an upper end of the steel pipe, and a steel pipe upper end cut portion and a T-shaped steel web portion being welded.   The precast cross beam according to claim 1, wherein the upper end of the steel pipe and the flange portion of the T-shaped steel are welded.   2. A concrete placement hole is formed above the steel pipe, a slip stopper is installed on an outer peripheral surface of the lower end of the steel pipe or in the vicinity of the lower end, and concrete is filled into the steel pipe from the placement hole to a predetermined height. Or the precast cross beam of 2.   The precast cross beam according to any one of claims 1 to 3, wherein the T-shaped steel is covered with reinforced concrete.   The precast cross beam according to claim 4, wherein a stopper is installed on a contact surface between the T-shaped steel and the concrete of the steel pipe.   For the portion of the T-shaped steel that protrudes from the steel pipe, a lower flange is welded to the T-shaped steel, or a lower flange that fits inside the steel pipe is removed instead of the T-shaped steel. The precast cross beam according to any one of claims 1 to 5, wherein a portion projecting from the steel pipe is made into an H-shaped steel material by using steel.   The precast cross beam according to any one of claims 1 to 5, wherein a π-shaped steel is used instead of the T-shaped steel. A pier using the precast horizontal beam according to claim 1 as a pier horizontal beam,
A steel pipe pier column with a stopper installed on the inner peripheral surface near the upper end or near the upper end is constructed, and the steel pipe portion of the precast horizontal beam is inserted into the steel pipe pier column, and concrete is placed in the gap between the steel pipe pier column and the steel pipe portion. A pier characterized by joining by filling.   A projection is installed on the inner peripheral surface of a predetermined height from the upper end of the steel pipe pier column, and the circular mold is placed in a diaphragm shape by dropping the circular mold on the projection, and then the precast horizontal beam In the state where the lower surface of the steel pipe part is in contact with the circular formwork, concrete is cast into the steel pipe pier column from the gap at the upper end of the steel pipe pier column or the hole previously opened in the precast lateral beam. The pier according to claim 8.   The bridge pier according to claim 8 or 9, wherein a spiral steel pipe is used for the steel pipe pier column.   At least the pile head has a diameter larger than the diameter of the steel pipe pier column, and after constructing a steel pipe pile with a stopper installed on the inner peripheral surface near the upper end or the upper end, the lower end or the vicinity of the lower end of the steel pipe pier column A slip stopper is installed on the outer peripheral surface of the steel pipe, the steel pipe bridge pier column is inserted into the steel pipe pile, and the gap between the steel pipe bridge pier column and the steel pipe pile is filled with concrete to join them. The pier according to any one of the above.   A projection is installed on the inner peripheral surface of a predetermined height from the upper end of the steel pipe pile, and the circular mold is placed in a diaphragm shape by dropping the circular mold on the projection, and then the steel pipe pier column is Fill the gap between the steel pipe pier column and the steel pipe pile with concrete in the state where it is inserted into the steel pipe pile and the bottom surface of the steel pipe pier column is in contact with the circular formwork, and also fill the concrete inside the pier column in the same section. The pier according to claim 11.