JP2010236281A - Steel floor slab structure and construction method for reinforcing steel slab floor slab - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steel floor slab structure of a bridge which does not need to use a panel having a special shape such as a panel having a through-hole even when using construction parts such as bolts having projecting portions which project from the upper surface of a deck plate upward, which has a high adhesive force between the deck plate and the panel, and which has a generally high strength. <P>SOLUTION: This steel floor slab structure includes a deck plate 102, a plurality of vertical ribs 104, lateral ribs extending across the vertical ribs, a thin layer pavement 4, and construction parts 5 on the deck plate 102. The steel floor slab structure further includes a first panel layer 2 disposed on the upper surface of the deck plate 102 through an adhesive agent layer in the area other than the areas of the construction parts 5 and a second panel layer 3 disposed on the upper surface of the first panel layer 2 through an adhesive agent layer. Each of the first panel layer 2 and the second panel layer 3 is formed of a panel made of a cement hard body having a compression strength of 60 N/mm<SP>2</SP>or higher, a bending strength of 20 N/mm<SP>2</SP>or higher. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a steel deck structure of a bridge and a steel deck reinforcement method.

Steel floor slab structures are used for bridges such as long-span bridges because they are lightweight.
Here, an example of a general steel deck structure is shown in FIG. In FIG. 4, the steel plate slab structure 100 includes a deck plate 102, a plurality of vertical ribs 104 extending on the lower surface of the deck plate 102 in parallel with the longitudinal direction of the steel plate slab structure 100 (longitudinal direction of the bridge), A horizontal rib 106 extending across the vertical rib 104, a main girder 110 supporting the vertical rib 104 and the horizontal rib 106, and a pavement 108 provided on the upper surface of the deck plate 102 are provided.
However, in recent years, there have been many reports of fatigue damage, particularly damage to the welded part between the bottom surface of the deck plate and the vertical ribs, mainly in bridges with heavy traffic. It is required to construct a high-strength steel slab structure that can suppress the occurrence of severe damage.

  As such a high-strength steel slab structure, for example, a deck plate, a plurality of vertical ribs extending in parallel to the longitudinal direction of the bridge on the lower surface of the deck plate, and perpendicular to the longitudinal direction of the bridge A concrete precast panel laid on the upper surface of the deck plate in a steel floor slab structure of a bridge having a horizontal rib extending across the vertical rib and a pavement provided on the upper surface of the deck plate And a steel floor slab structure of a bridge comprising a joining means (for example, one containing an adhesive) for joining the concrete precast panel to the upper surface of the deck plate has been proposed (Patent Document 1).

JP 2006-348487 A

According to the technique described in Patent Document 1, since the concrete precast panel is used, the bridge is reinforced in a short time without requiring long-time traffic interruption as in the case of construction using cast-in-place concrete. It can be performed. Moreover, since the said concrete precast panel can be conveyed manually, it can reinforce a bridge without using a large sized machine.
However, when using a concrete precast panel, there are the following problems.
The concrete precast panel is usually produced as a flat plate having a certain thickness and having the entire upper and lower surfaces formed flat. In this case, if there is a building part (for example, a bolt) having a protruding part protruding upward from the upper surface of the deck plate, this building part becomes an obstacle and the concrete precast panel is placed on the upper surface of the deck plate. Can not be.

In the technique described in Patent Document 1, when a shear connector (reference numeral 20 in FIG. 2) that is a building component having a protruding portion protruding upward from the upper surface of the deck plate is used, a through hole corresponding to the protruding portion and A concrete precast panel having countersunk holes (reference numerals 12a and 12b in FIG. 2) is used. The shear connector is a member that is responsible for horizontal and shear forces acting on the concrete precast panel. In this case, there is a problem that a concrete precast panel having a special shape such as having a through hole has to be prepared.
The present invention does not require the use of a specially shaped panel such as having a through-hole, even when a building component such as a bolt having a protruding portion protruding upward from the upper surface of the deck plate is used. To provide a steel floor slab structure of a bridge having a large adhesion force between a plate and a panel, having a large strength as a whole, and excellent in fatigue durability, and a steel floor slab reinforcing method by forming the steel floor slab structure With the goal.

As a result of intensive studies to solve the above problems, the present inventor has found that the above object of the present invention can be achieved by forming specific two panel layers, and has completed the present invention.
That is, the present invention provides the following [1] to [5].
[1] A deck plate, a plurality of vertical ribs extending parallel to the longitudinal direction of the bridge on the lower surface of the deck plate, and extending across the vertical ribs perpendicular to the longitudinal direction of the bridge Steel for a bridge including a lateral rib, a thin pavement provided above the deck plate, and a building part attached to the deck plate so as to have a protruding portion protruding upward from an upper surface of the deck plate A floor slab structure, the height of the protruding part of the building part disposed on the upper surface of the deck plate, excluding the building part and its surrounding area, via a first adhesive layer A first panel layer having the above thickness, and the building component and its surroundings disposed below the thin pavement via a second adhesive layer on the upper surface of the first panel layer. Second panel layer over the entire area including the area And each of the first panel layer and the second panel layer is constituted by a panel made of a cementitious hardened body having a compressive strength of 60 N / mm ² or more and a bending strength of 20 N / mm ² or more. Steel floor slab structure characterized by

[2] The steel slab structure according to [1], wherein the first panel layer is formed by laying a plurality of panels made of a rectangular flat cementitious hardened body.
[3], wherein the panels, cement, fine powder, inorganic powder of Blaine specific surface area of 3,500~10,000cm ² / g, a maximum particle size of less 2mm fine bone BET specific surface area of 5~25m ² / g The steel slab structure according to the above [1] or [2], comprising a cured product of a composition containing a material, a water reducing agent, fibers, and water.
[4] The steel deck structure according to any one of [1] to [3], wherein the first adhesive layer and the second adhesive layer are made of a cured product of an acrylic resin adhesive.
[5] A steel plate slab reinforcing method by forming a new steel plate structure according to any one of the above [1] to [4] instead of the existing steel plate structure, After removing at least a part of the pavement of the floor slab structure to expose the upper surface of the deck plate, an adhesive is applied to the upper surface of the deck plate, and then the area excluding the building component and the surrounding area A step of forming the first panel layer, a step of forming the second panel layer after applying an adhesive to the upper surface of the first panel layer, and an upper surface of the second panel layer. And a step of forming the thin-layer pavement.

According to the steel slab structure of the present invention, it is necessary to use a panel having a special shape such as having a through hole even when a building part such as a bolt having a protruding portion protruding upward from the upper surface of the deck plate is used. For example, it can be constructed using only a panel whose front and back are all flat surfaces having no irregularities.
Further, the steel slab structure of the present invention has a large adhesion between the deck plate and the panel, has a large strength as a whole, and is excellent in fatigue durability.
Furthermore, in the steel slab structure of the present invention, since a panel (precast molded body) made of a cementitious hardened body is used, it takes a long time for curing as in the case of construction using on-site concrete. Bridges can be reinforced in a short time without the need to block traffic. Moreover, since the said panel can be conveyed manually, a bridge can be reinforced without using a large sized machine.
The steel slab structure of the present invention can be employed both when a bridge is newly formed and when an existing bridge is reinforced.

It is sectional drawing which shows the steel deck structure of this invention typically. It is sectional drawing which expands and shows the state cut | disconnected by the AA line in FIG. It is sectional drawing which shows the test body for measuring the adhesion strength of a deck plate, a 1st panel layer, and a 2nd panel layer. It is a perspective view which shows typically an example of a general steel deck structure.

The steel slab structure of the present invention will be described with reference to FIGS. In FIG. 1 and FIG. 2, the same reference numerals are used for the description of the components common to the steel plate structure 100 of the bridge shown in FIG. FIG. 4 schematically shows an example of a general steel slab structure, but also shows an example of a steel slab structure before reinforcement in the present invention.
In FIG. 1, a steel floor slab structure 1 of the present invention includes a deck plate 102, vertical ribs 104, horizontal ribs 106 (not shown, see FIG. 4), an existing pavement 108 that is a pavement, bolts, and the like. And a laminated body including the first panel layer 2, the second panel layer 3, and the thin pavement 4 which are pavement parts after reinforcement.
From the viewpoint of fatigue durability of the steel deck structure, it is preferable to fill the space 6 in the vicinity (periphery) of the building component 5 in FIG. 1 with a cementitious filler or a synthetic resin adhesive. When using the cementitious filler preferably has a compressive strength after curing is 10 N / mm ² or more, it is more preferable to be 20 N / mm ² or more. When a synthetic resin adhesive is used, an acrylic resin adhesive is preferable.
The vertical ribs 104 are plate-like members having a substantially trapezoidal or U-shaped cross section, and a plurality of vertical ribs 104 are extended in parallel to the longitudinal direction of the steel deck structure 1. The plurality of vertical ribs 104 are all fixed to the bottom surface of the deck plate 102 by welding.

The transverse rib 106 (see FIG. 4) is a plate-like member having a substantially T-shaped longitudinal section, and extends across the longitudinal rib 104 perpendicular to the longitudinal direction of the steel deck structure 1. It is installed. A plurality of the lateral ribs 106 are provided at predetermined intervals in the longitudinal direction of the steel deck structure 1. All the lateral ribs 106 are fixed to the lower surface of the deck plate 102.
The pavement 108 is a pavement surface forming portion of the steel slab structure 1 made of, for example, asphalt pavement.
As shown in FIG. 2, the paved portion after reinforcement includes a deck plate 102, a first adhesive layer 7, a first panel layer 2, a second adhesive layer 8, a second panel layer 3, and a thin layer. The pavement 4 is laminated in that order.
The first adhesive layer 7 and the second adhesive layer 8 are usually made of a cured product of a synthetic resin adhesive, and preferably have high adhesive strength and a high curing rate even at low temperatures. It consists of a cured product of an acrylic resin adhesive.

The first panel layer 2 and the second panel layer 3 are each formed by using a panel made of a cementitious hardened body having specific mechanical strength (compressive strength, bending strength).
The first panel layer 2 is formed in a region excluding the building component 5 and its surrounding region so as to have a thickness equal to or higher than the height of the protruding portion of the building component 5 from the deck plate 102.
The first panel layer 2 is preferably formed by laying a plurality of panels made of a rectangular cementitious hardened body. Although the dimension of this panel should just be defined according to the attachment place and shape of building component 5, it is 50-200 cm (length) x20-80 cm (width) x10-30 mm (thickness), for example.
The panel which comprises the 1st panel layer 2 can form the convex part and / or recessed part of 2 mm or less in height in the single side | surface (surface on the side adhering to the deck plate 102). In this case, the occurrence of air accumulation between the deck plate 102 and the first panel layer 2 is suppressed, and fatigue damage caused by the air accumulation (mainly at the junction between the bottom surface of the deck plate and the vertical ribs). It is possible to suppress the occurrence of damage that breaks a certain welded portion and arrange the panel constituting the first panel layer 2 with high accuracy at a predetermined position without sliding. Projections and / or recesses having a height of 2 mm or less are particularly effective when the dimensions of the panel constituting the first panel layer 2 are large.

The second panel layer 3 is formed by spreading one or more panels made of a rectangular cementitious hardened body. The thickness of the panel may be determined in consideration of the thicknesses of the pavement 108, the first panel layer 2, and the thin pavement 4. The dimensions of the panel are, for example, 100 to 200 cm (length) × 30 to 80 cm (width) × 10 to 30 mm (thickness).
The total thickness of the first panel layer 2 and the second panel layer 3 is preferably 30 to 60 mm, more preferably 35 to 50 mm, and particularly preferably 35 to 45 mm. When the thickness is less than 30 mm, the reinforcing effect of the steel slab is insufficient, and the fatigue durability is lowered, which is not preferable. On the other hand, if the thickness exceeds 60 mm, the panel manufacturing cost increases, which is not preferable.

Each of the first panel layer 2 and the second panel layer 3 is formed of a panel made of a specific cementitious hardened body.
The compressive strength of the cementitious cured body is 60 N / mm ² or more, preferably 100 N / mm ² or more, and particularly preferably 120 N / mm ² or more. The upper limit of the compressive strength is not particularly limited, but is usually 300 N / mm ² .
Flexural strength of the cementitious cured product, 20 N / mm ² or more, preferably 25 N / mm ² or more, particularly preferably 30 N / mm ² or more. The upper limit of the bending strength is not particularly limited, but is usually 50 N / mm ² .
By using a panel made of a cementitious hardened body having such compressive strength and bending strength, a steel deck structure with excellent fatigue durability can be obtained. When the compressive strength of the hardened cementitious body is less than 60 N / mm ² or the bending strength is less than 20 N / mm ² , the fatigue durability of the panel is lowered, and partial breakage of the steel slab structure is likely to occur.

The panel made of the cementitious hardened body has (A) cement, (B) fine powder having a BET specific surface area of 5 to 25 m ² / g, and (C) a brane specific surface area of 3,500 to 10,000 cm ² / g. A cured product of an inorganic powder, (D) a fine aggregate having a maximum particle size of 2 mm or less, (E) a water reducing agent, (F) water, and (G) a fiber is preferable.
(A) Although it does not specifically limit as a kind of cement, For example, various Portland cements, such as normal Portland cement, early strong Portland cement, moderately-heated Portland cement, low heat Portland cement, can be used.
When trying to improve the early strength of the panel, it is preferable to use early-strength Portland cement. When trying to improve the fluidity of the compound, use moderately hot Portland cement or low-heat Portland cement. It is preferable to do.

(B) Examples of the fine powder having a BET specific surface area of 5 to 25 m ² / g include silica fume, silica dust, fly ash, slag, volcanic ash, silica sol, precipitated silica, and limestone powder. In general, silica fume and silica dust have a BET specific surface area of 5 to 25 m ² / g and do not need to be pulverized, and thus are suitable as the fine powder of the present invention. Moreover, limestone powder is also suitable as the fine powder of the present invention from the viewpoints of pulverizability and fluidity.
(B) The BET specific surface area of fine powder is 5-25 m < ² > / g, Preferably it is 7-15 m < ² > / g. When the value is less than 5 m ² / g, the effect of improving the strength, denseness and impact resistance of the panel is lowered. On the other hand, when the value exceeds 25 m ² / g, the unit water amount increases, and the strength, denseness, impact resistance, and the like of the panel decrease.
(B) The compounding quantity of fine powder becomes like this. Preferably it is 5-50 mass parts with respect to 100 mass parts of (A) cement, More preferably, it is 10-40 mass parts. If the blending amount is out of the above range, the effect of improving the strength, denseness, impact resistance and the like of the panel is lowered.

(C) The inorganic powder having a Blaine specific surface area of 3,500 to 10,000 cm ² / g is an inorganic powder other than cement, such as slag, limestone powder, feldspar, mullite, alumina powder, quartz powder, fly ash , Volcanic ash, silica sol, carbide powder, nitride powder and the like. Among these, slag, fly ash, limestone powder, and quartz powder are preferably used in terms of cost and quality stability after curing.
(C) The brane specific surface area of the inorganic powder is 3,500 to 10,000 cm ² / g, preferably 4,000 to 9,000 cm ² / g, particularly preferably 5,000 to 9,000 cm ² / g. . When the value is less than 3,500 cm ² / g, the effect of improving the strength, denseness, impact resistance and the like of the panel is lowered. On the other hand, when the value exceeds 10,000, the effect of improving the fluidity of the blend and the effect of improving the strength, denseness, impact resistance and the like of the panel are lowered, and the cost is further increased.
(C) The compounding quantity of inorganic powder becomes like this. Preferably it is 5-55 mass parts with respect to 100 mass parts of (A) cement, More preferably, it is 10-50 mass parts. When the blending amount is out of the above range, the effect of improving the fluidity and workability of the blend and the effect of improving the strength, denseness, impact resistance and the like of the panel are lowered.

(D) Examples of fine aggregates having a maximum particle size of 2 mm or less include river sand, land sand, sea sand, crushed sand, silica sand, and mixtures thereof.
(D) The maximum particle size of the fine aggregate is 2 mm or less, preferably 1.5 mm or less, particularly preferably 1 mm or less. When the maximum particle size exceeds 2 mm, the strength of the panel may be lowered, and it may be difficult to produce a thin panel.
The blending amount of (D) fine aggregate is preferably 50 to 250 parts by mass, more preferably 80 to 180 parts by mass with respect to 100 parts by mass of (A) cement. When the blending amount is out of the above range, the strength of the panel may be lowered and the shrinkage may be increased.

(E) As a water reducing agent, a lignin type, naphthalenesulfonic acid type, melamine type, polycarboxylic acid type water reducing agent, AE water reducing agent, high performance water reducing agent, or high performance AE water reducing agent can be used. Among these, it is preferable to use a polycarboxylic acid-based high-performance water reducing agent or a high-performance AE water reducing agent. By blending a water reducing agent, the fluidity and workability of the blend, the denseness and strength of the panel, and the like can be improved.
(E) The blending amount of the water reducing agent is preferably 0.1 to 4.0 parts by mass, more preferably 0.1 to 1.0 parts by mass in terms of solid content with respect to 100 parts by mass of (A) cement. is there. If the blending amount is less than 0.1 parts by mass, it becomes difficult to knead the blend, and the fluidity becomes extremely low, so that molding becomes difficult. On the other hand, if the blending amount exceeds 4.0 parts by mass, material separation may occur, and the denseness and strength after curing may decrease.

(F) As water, tap water etc. can be used.
The water / cement ratio in the formulation constituting the panel is preferably 10-30% by weight, more preferably 15-25% by weight. When the water / cement ratio is less than 10% by mass, it is difficult to knead the blend, and the fluidity is extremely low, which makes molding difficult. On the other hand, if the water / cement ratio exceeds 30% by mass, the denseness and strength after curing may decrease.

(G) Examples of the fibers include metal fibers, organic fibers, and carbon fibers.
Examples of the metal fibers include steel fibers and amorphous fibers, among which steel fibers have high strength and are preferably used from the viewpoint of cost and availability.
The metal fibers preferably have a diameter of 0.01 to 1.0 mm and a length of 2 to 30 mm. When the diameter is less than 0.01 mm, the proof stress of the fiber itself is insufficient, and it is easy to break when subjected to tension. On the other hand, when the diameter exceeds 1.0 mm, the number of the same compounding amount decreases, and bending The effect of improving strength is reduced. On the other hand, if the length is less than 2 mm, the effect of improving the bending strength is lowered. On the other hand, if the length exceeds 30 mm, fiber balls are likely to be produced during kneading.
The blending amount of the metal fiber is preferably 0.1 to 4.0%, more preferably 0.5 to 3.5%, and still more preferably 0.7 to 3.0% in a volume of the blend of 100%. is there. When the blending amount is less than 0.1%, the bending strength and fracture energy of the panel are reduced. On the other hand, when the blending amount exceeds 4.0%, the unit water amount increases, and the strength and breaking energy of the panel are decreased.

As the organic fiber, vinylon fiber, polypropylene fiber, polyethylene fiber, aramid fiber, or the like can be used. Among these, vinylon fibers are preferable from the viewpoints of strength, cost, availability, and the like.
As the carbon fiber, a PAN-based carbon fiber or a pitch-based carbon fiber can be used.
The organic fiber or carbon fiber preferably has a diameter of 0.005 to 1.0 mm and a length of 2 to 30 mm. When the diameter is less than 0.005 mm, the proof stress of the fiber itself is insufficient, and it is easy to break when subjected to tension. On the other hand, when the diameter exceeds 1.0 mm, the number at the same blending amount is reduced and curing is performed. The effect of improving body destruction energy is reduced. Further, if the length is less than 2 mm, the adhesion to the matrix is reduced, and the effect of improving the fracture energy and the like is reduced. On the other hand, if the length is more than 30 mm, fiber balls are likely to be produced during kneading. Become.
The compounding amount of the organic fiber or carbon fiber is preferably 0.5 to 10%, more preferably 1.0 to 7.0%, still more preferably 1.5 to 5.0, with the volume of the compound being 100%. %. If the blending amount is less than 0.5%, the destruction energy of the panel becomes small, such being undesirable. On the other hand, if the blending amount exceeds 10%, the unit water amount increases, and the strength and breaking energy of the panel become small, which is not preferable.

Furthermore, in this invention, in order to improve the toughness of a panel, (H) fibrous particle or flaky particle | grains can be mix | blended with a compound.
Examples of the fibrous particles include wollastonite, bauxite, mullite, and the like. Examples of the flaky particles include mica flakes, talc flakes, vermiculite flakes, and alumina flakes.
The average particle size of the fibrous particles or flaky particles is preferably 1 mm or less. By blending fibrous particles or flaky particles having such an average particle size, the toughness of the panel can be improved. When the average particle size exceeds 1 mm, the fluidity of the blend, the strength after curing, and the like are not preferable.
In addition, the particle size of the particle | grains in this invention is the largest dimension (especially the length in fibrous particle | grains).
(H) The blending amount of the fibrous particles or flaky particles is 35 parts by mass or less with respect to 100 parts by mass of (A) cement from the viewpoint of fluidity of the blend, strength after curing, toughness and the like. Preferably, it is 0.1-20 mass parts.
In addition, in the fibrous particle, it is preferable that the acicular degree represented by the ratio of length / diameter is 3 or more from the viewpoint of increasing the toughness after curing.

A panel used in the first panel layer 2 or the second panel layer 3 of the present invention can be obtained by kneading, molding, curing, or the like, the composition containing the above components.
The method for kneading the blend is not particularly limited, and the blend can be kneaded using a conventional mixer such as an omni mixer, a pan-type mixer, a biaxial kneader mixer, a tilt cylinder mixer, and the like.
The forming / curing method is not particularly limited, but it is preferable to perform the following primary curing / secondary curing from the viewpoints of panel productivity and strength development.
(1) The kneaded cement composition is molded using a predetermined mold and subjected to primary curing. The molding method at this time is not particularly limited, but a conventional molding method such as casting can be employed. Examples of the primary curing method include a method in which the cement composition kneaded in a mold is accommodated and left at 5 to 40 ° C. for a predetermined time (about 3 to 48 hours).
(2) After completion of primary curing, the mold is removed, and then secondary curing is performed to produce a cementitious cured body. Examples of the secondary curing method include a steam curing method at 75 to 95 ° C. for 10 to 48 hours. The hardened cementitious body at the time of demolding preferably has a compressive strength of 10 N / mm ² or more. If the compressive strength is less than 10 N / mm ^2, demolding becomes difficult.

Next, the reinforcing method of the steel deck structure of the present invention will be described.
First, after removing at least a part of the existing pavement 108 having a steel slab structure to expose the upper surface of the deck plate 102, an adhesive is applied to the upper surface of the deck plate 102.
Next, a plurality of panels for forming the first panel layer are spread over the area excluding the building component 5 and the surrounding area, thereby forming the first adhesive layer 7 and the first panel layer 2.
Thereafter, an adhesive is applied to the upper surface of the first panel layer 2, and one or more panels for forming the second panel layer are spread, and the second adhesive layer 8 and the second adhesive layer 8 A panel layer 3 is formed.
From the viewpoint of fatigue durability of the steel deck structure, it is preferable to fill the space 6 in the vicinity (periphery) of the building component 5 in FIG. 1 with a cementitious filler or a synthetic resin adhesive. When a cementitious filler is used, one having a compressive strength after curing of 10 N / mm ² or more is preferable, and one having 20 N / mm ² or more is more preferable. When a synthetic resin adhesive is used, an acrylic resin adhesive is preferable.
Thereafter, a thin pavement 4 is formed on the upper surface of the second panel layer 3. The thin pavement 4 is formed so as to be flush with the other pavement portions 108 to form a pavement surface having a steel slab structure.
Adhesion strength between the layers in the steel deck structure of the present invention is preferably 2.0 N / mm ² or more, more preferably 2.5 N / mm ² or more. Note that the adhesion strength between the first panel layer and the second panel layer is usually larger than the adhesion strength between the deck plate and the first panel layer. Therefore, the adhesion strength (tensile strength when pulled in the direction perpendicular to the pavement surface) in the steel slab structure of the present invention can be expressed as the adhesion strength between the deck plate and the first panel layer.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.
1. Materials used The following materials were used.
(A) Cement: Low heat Portland cement (manufactured by Taiheiyo Cement)
(B) Fine powder; silica fume (BET specific surface area: 10 m ² / g)
(C) Inorganic powder; quartz powder (Blaine specific surface area: 7,000 cm ² / g)
(D) Fine aggregate: silica sand No. 5 (maximum particle size: 1 mm or less)
(E) Water reducing agent; polycarboxylic acid-based high-performance water reducing agent (F) water; tap water (G) metal fiber; steel fiber (diameter: 0.2 mm, length: 15 mm)

2. Performance of Compound and Hardened Body (A) 100 parts by mass of low heat Portland cement, (B) 32 parts by mass of silica fume, (C) 35 parts by mass of quartz powder, (D) 105 parts by mass of fine aggregate, (E) 0 water reducing agent .8 parts by mass (converted to solid content), (F) 22 parts by mass of water, and (G) steel fiber (amount that is 2% of the total volume of the compound) are put into a biaxial kneader, kneaded and compounded I got a thing.
The flow value of the obtained blend, and the compression strength and bending strength of the cured product of the blend were measured by the following methods.
(Flow value)
The flow value of the blend was measured in the method described in “JIS R 5201 (Cement physical test method) 11. Flow test” without performing 15 drop motions. As a result, the flow value was 270 mm.
(Compressive strength)
The blend was poured into a φ50 × 100 mm formwork, placed at 20 ° C. for 24 hours, and then steam-cured at 90 ° C. for 48 hours to obtain a cured product. The compressive strength of the cured product was measured in accordance with “JIS A 1108 (Concrete Compression Test Method)” and found to be 210 N / mm ² . In addition, this compressive strength is an average value of three hardening bodies.
(Bending strength)
The blend was poured into a 4 × 4 × 16 cm mold, pre-positioned at 20 ° C. for 24 hours, and then steam-cured at 90 ° C. for 48 hours to obtain a cured product. The bending strength of the cured product was measured in accordance with “JIS R 5201 (cement physical test method)” and found to be 47 N / mm ² . In addition, this bending strength is an average value of three hardening bodies. The loading conditions in the measurement were four-point bending with a distance between the lower fulcrums of 12 cm and a distance between the upper fulcrums of 4 cm.

3. Preparation of test body 2. The composition obtained in the above was poured into a mold having an internal space of 400 mm in length, 400 mm in width, and 20 mm in thickness, pre-positioned at 20 ° C. for 24 hours, and then steam-cured at 90 ° C. for 48 hours. Then, it demolded and the panel X which has the said shape was obtained.
In addition, the above 2. The composition obtained in (1) was poured into a mold having an internal space with a length of 1,650 mm, a width of 400 mm, and a thickness of 20 mm, pre-positioned at 20 ° C. for 24 hours, and then steam-cured at 90 ° C. for 48 hours. Then, it demolded and the panel Y which has the said shape was obtained.
Next, as shown in FIG. 3, after applying an acrylic resin adhesive (trade name: Hard Rock II) to the top surface of the deck plate 102 (9 mm thick steel plate) to a thickness of 2 mm, Two sheets of the panel X were bonded to the coated surface, and allowed to stand at 30 ° C. for 24 hours to form the first adhesive layer 7 and the first panel layer 2. The symbol P in FIG. 3 represents the length of the panel X of 400 mm.
Thereafter, an acrylic resin adhesive (trade name: Hard Rock II) was applied to the upper surface of the first panel layer 2 composed of two panels X so as to have a thickness of 2 mm. One panel Y was adhered and allowed to stand at 30 ° C. for 24 hours to form the second adhesive layer 8, the second panel layer 3, and the space 13. A symbol L in FIG. 3 represents the length of the panel Y of 1,650 mm.
A cylindrical test body (core) 12 having a diameter of 10 cm was pulled out at any six locations of the obtained laminate 11. Using these cores (six of No. 1 to No. 6), the tensile strength (adhesion strength between layers) of the laminate 11 was measured according to the Kenken-type adhesion test.
The results are shown in Table 1. From Table 1, it can be seen that the minimum value of the tensile strength in the six cores is 2.87 N / mm ² , which has a large strength as a whole steel deck and can be expected to have excellent fatigue durability.

1 Steel floor slab structure 2 First panel layer 3 Second panel layer 4 Thin layer pavement 5 Building parts (bolts, etc.)
6 Space 7 First adhesive layer 8 Second adhesive layer 11 Specimen (laminate)
12 Cylindrical specimen (core)
13 Space 100 Steel deck structure 102 Deck plate 104 Vertical rib 106 Horizontal rib 108 Pavement 110 Main girder

Claims (5)

A deck plate, a plurality of vertical ribs extending in parallel to the longitudinal direction of the bridge on the lower surface of the deck plate, and a lateral rib extending across the vertical rib perpendicular to the longitudinal direction of the bridge A steel floor slab structure of a bridge including a thin pavement provided above the deck plate, and a building component attached to the deck plate so as to have a protruding portion protruding upward from an upper surface of the deck plate Because
A thickness of the upper surface of the deck plate that is greater than the height of the projecting portion of the building component disposed in the region excluding the building component and its peripheral region via a first adhesive layer. A panel layer,
A second panel layer over the entire area including the building component and its surrounding area, disposed below the thin pavement via a second adhesive layer on the upper surface of the first panel layer; Have
Each of said 1st panel layer and 2nd panel layer is comprised by the panel which consists of a cementitious hardening body whose compressive strength is 60 N / mm < ² > or more and bending strength is 20 N / mm < ² > or more. Steel floor slab structure.   2. The steel slab structure according to claim 1, wherein the first panel layer is formed by laying a plurality of panels made of a rectangular flat cementitious hardened body. Wherein the panels, cement, fine powder of BET specific surface area of 5~25m ² / g, the inorganic powder Blaine specific surface area of 3,500~10,000cm ² / g, a maximum particle size of 2mm or less fine aggregate, water reducing The steel slab structure according to claim 1 or 2, comprising a hardened body of a composition containing an agent, fibers, and water.   The steel floor slab structure according to any one of claims 1 to 3, wherein the first adhesive layer and the second adhesive layer are made of a cured product of an acrylic resin adhesive. In place of the existing steel slab structure, a steel slab reinforcement construction method by forming a new steel slab structure according to any one of claims 1 to 4,
After removing at least a part of the existing pavement of the steel slab structure to expose the upper surface of the deck plate, an adhesive is applied to the upper surface of the deck plate, and then the building component and the surrounding area Forming the first panel layer in a region excluding
After applying an adhesive on the upper surface of the first panel layer, forming the second panel layer;
Forming a thin pavement on the upper surface of the second panel layer.

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