CN111255159A - Thin-wall steel composite column partially filled with ultrahigh-toughness cement-based composite material - Google Patents
Thin-wall steel composite column partially filled with ultrahigh-toughness cement-based composite material Download PDFInfo
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- CN111255159A CN111255159A CN202010136393.4A CN202010136393A CN111255159A CN 111255159 A CN111255159 A CN 111255159A CN 202010136393 A CN202010136393 A CN 202010136393A CN 111255159 A CN111255159 A CN 111255159A
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
- E04C3/00—Structural elongated elements designed for load-supporting
- E04C3/30—Columns; Pillars; Struts
- E04C3/36—Columns; Pillars; Struts of materials not covered by groups E04C3/32 or E04C3/34; of a combination of two or more materials
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
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Abstract
The invention discloses a thin-wall steel composite column partially filled with an ultrahigh-toughness cement-based composite material. The invention can overcome the defects of overlarge self weight, complex node structure, complicated construction process and large quantity of building templates of the existing section steel concrete column, and has better manufacturing cost, steel content, section flexibility, crack resistance and deformation capacity than the existing partially-filled concrete combined column.
Description
Technical Field
The invention belongs to the technical field of building structures, and particularly relates to a thin-wall steel combined column partially filled with an ultrahigh-toughness cement-based composite material.
Background
At present, the steel and concrete combined column is widely applied to constructional engineering, and has high bearing capacity and good fire resistance. However, the concrete material has low tensile strength, is easy to crack, has poor ductility, is not matched with the deformation capability of the steel column, and influences the mechanical property of the combined column. And for the combined column, the section steel is completely filled in the concrete, so that the combined column has the disadvantages of heavy weight, complex node and long construction period.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a thin-wall steel combined column partially filled with an ultrahigh-toughness cement-based composite material, which has the advantages of flexible section form, light dead weight, difficult cracking, good ductility and good stress performance, and aims to overcome the defects in the prior art.
The invention adopts the following technical scheme:
the thin-wall steel composite column comprises thin-wall flange plates, wherein the two thin-wall flange plates are arranged in parallel, the middle parts of the thin-wall flange plates are connected through thin-wall webs to form an H-shaped structure, the outer edges of the two thin-wall flange plates are connected through tie bars, the ultrahigh-toughness cement-based composite material is filled between the thin-wall webs and the thin-wall flange plates, and the ultrahigh-toughness cement-based composite material can be wrapped by the thin-wall flange plates and the thin-wall webs to form a columnar structure.
In particular, the tie bars are perpendicular to the two thin-walled flange plates and are arranged parallel to the thin-walled web.
Specifically, the tie bars comprise a plurality of tie bars, equally spaced between two thin-walled flange plates.
Furthermore, a protective layer with the thickness of 30-50 mm is reserved on the outer edge of the tie bar, which is away from the thin-wall flange plate.
Specifically, the ultrahigh-toughness cement-based composite material comprises cement, fly ash, quartz sand, a water reducing agent, water and polyvinyl alcohol fiber, wherein the cement: fly ash: quartz sand: water: 1 of water reducing agent: 1.5: 1.62: 0.9: 0.025, and the volume ratio of the polyvinyl alcohol fiber is 1.5-2%.
Further, mixing and stirring cement, fly ash and fine sand for 1-2 min at room temperature; adding polyvinyl alcohol fibers, and continuously stirring for 3-5 min until the mixture has no polyvinyl alcohol fiber agglomeration phenomenon; and finally, adding the water reducing agent into water, stirring uniformly, adding the mixture into the mixture, and stirring for 3-5 min to prepare the ultra-high-toughness cement-based composite material.
Specifically, the thin-wall flange plate and the middle thin-wall web plate are connected in a fillet welding mode.
Furthermore, the section of the thin-wall steel combination column is square or rectangular.
Compared with the prior art, the invention has at least the following beneficial effects:
according to the thin-wall steel combined column partially filled with the ultrahigh-toughness cement-based composite material, the ultrahigh-toughness cement-based composite material is filled between the thin-wall flange and the thin-wall web, so that a template at the thin-wall flange and the thin-wall web can be omitted when the ultrahigh-toughness cement-based composite material is filled, and the template is saved; the integral structure is succinct, and the thin wall flange board exposes, makes things convenient for the nodal connection, and the preparation is convenient, shortens construction cycle.
Furthermore, the combined column is formed by welding thin-wall flanges and thin-wall webs with any section size, the sections of the combined column can be combined according to engineering conditions, and the section form is flexible.
Furthermore, a 30-50 mm protective layer is reserved at the position, away from the outer edge of the thin-wall flange plate, of the tie bar, so that the tie bar can be prevented from being rusted and losing efficacy.
Furthermore, the ultrahigh-toughness cement-based composite material shows good deformation capacity and crack resistance under the action of axial compression and tensile load, and the ultrahigh-toughness cement-based composite material and the thin-wall steel column have good cooperative deformation capacity, so that effective support can be provided for the thin-wall steel column, and the overall stability of the thin-wall steel column is improved;
furthermore, the tie bars welded between the thin-wall flange plates can improve the local buckling capacity of the thin-wall flange plates, and meanwhile, the tie bars, the thin-wall flange plates and the thin-wall web plates provide a restraining effect on the ultra-high-toughness cement-based composite material, so that the material performance is fully exerted.
Furthermore, the cross section of the column is square or rectangular, so that the column and the beam can be conveniently connected, and the construction is convenient.
In conclusion, the invention can overcome the defects of overlarge self weight, complex node structure, complicated construction process and the need of constructing a large number of templates of the existing section steel concrete column, and has better manufacturing cost, steel content, section flexibility, crack resistance and deformation capacity than the existing partially-filled concrete combined column.
The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.
Drawings
FIG. 1 is a schematic cross-sectional view of the present invention;
FIG. 2 is a three-dimensional schematic of the present invention;
fig. 3 is a schematic view of a casting surface of the present invention.
Wherein: 1. a thin-walled flange plate; 2. a thin-walled web; 3. a tie bar; 4. an ultra-high toughness cement-based composite material.
Detailed Description
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "one side", "one end", "one side", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention. In addition, in the description of the present invention, "a plurality" means two or more unless otherwise specified.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The ultra-high toughness cement-based composite material is characterized in that the fiber, the matrix and the interface of the fiber and the matrix in the cement-based composite material are improved based on the micro-mechanics principle, the tensile ductility and brittle fracture performance of the traditional concrete material are greatly improved by adding the high-performance polyvinyl alcohol fiber, and the ultra-high toughness cement-based composite material has the characteristics of high deformation capacity, good crack resistance and good ductility; and the ultrahigh-toughness cement-based composite material and the thin-wall steel column have good cooperative deformability.
Referring to fig. 1 and 2, the thin-walled steel composite column partially filled with ultra-high toughness cement-based composite material of the present invention includes a thin-walled flange plate 1, a thin-walled web 2, a tie bar 3, and an ultra-high toughness cement-based composite material 4.
The two thin-wall flange plates 1 are arranged in parallel, the middle of the two thin-wall flange plates are connected through a thin-wall web 2 to form an H-shaped structure, the two thin-wall flange plates 1 are connected through a tie bar 3, after the thin-wall flange plates 1 and the thin-wall web 2 are welded to form the H-shaped structure, the ultra-high-toughness cement-based composite material 4 is filled in a blank area formed by the thin-wall flange plates 1 at the two ends and the thin-wall web 2 respectively, the two parts are combined, due to the existence of the thin-wall web 2, the ultra-high-toughness cement-based composite material 4 cannot be completely filled, namely partial filling, and the ultra-high-toughness cement-based composite material is wrapped on three.
The thin-wall flange plate 1 and the thin-wall web plate 2 are hot-rolled thin-wall steel plates made of the same material.
The thin-wall flange plates 1 at two ends of the steel composite column and the thin-wall web plate 2 in the middle are connected in a fillet welding mode.
The tie rods 3 are arranged at intervals between the two thin-walled flange plates 1 in a manner perpendicular to the thin-walled flange plates 1 and parallel to the thin-walled web 2.
The section of the thin-wall steel combined column is square or rectangular.
The ultrahigh-toughness cement-based composite material 4 comprises cement, fly ash, quartz sand, a naphthalene-based superplasticizer, water and polyvinyl alcohol fibers, wherein the cement comprises the following components in percentage by mass: fly ash: quartz sand: water: 1 of water reducing agent: 1.5: 1.62: 0.9: 0.025, and the volume ratio of the polyvinyl alcohol fiber is 1.5-2%.
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Examples
Referring to fig. 3, the thin-wall steel composite column of the present invention is a square column with a side length of 450mm and a column height of 3.0m, and is partially filled with an ultra-high toughness cement-based composite material; the tie bars 3 are steel rods with the diameter of 14mm and are arranged at intervals of 450 mm; the thin-wall flange plate 1 and the thin-wall web plate 2 are both made of Q345-grade steel with the thickness of 6mm, the thin-wall flange plate 1 and the thin-wall web plate 2 are welded into an H shape, and the ultra-high toughness cement-based composite material 4 is filled between the thin-wall flange plate 1 and the thin-wall web plate 2.
The concrete construction process is as follows:
s1, welding the thin-wall flange plate 1 and the thin-wall web plate 2 by adopting welding rod arc welding and fillet welding to form an H-shaped thin-wall steel column;
s2, arranging tie bars 3 on the inner side of the thin-wall flange plate 1 at fixed intervals, positioning and perforating the thin-wall flange plate 1, then inserting the tie bars 3 into flange positioning holes, and finally performing double-sided spot welding in a welding rod arc welding manner;
s3, reserving a protective layer with the thickness of 30-50 mm at the position of the tie bar 3 from the outer edge of the thin-wall flange plate 1;
s4, pouring the ultra-high toughness cement-based composite material 4, filling the space between the thin-wall flange plate 1 and the thin-wall web plate 2, and mechanically planing the two ends of the combined column after natural curing is finished to obtain the thin-wall steel combined column partially filled with the ultra-high toughness cement-based composite material.
When the ultra-high toughness cement-based composite material is manufactured, a vertical forced stirrer is adopted, and the stirring sequence is as follows: firstly, weighing cement, fly ash, fine sand, a water reducing agent and water; mixing and stirring the weighed cement, the coal ash and the fine sand for 1-2 minutes; manually adding polyvinyl alcohol fibers and stirring for 3-5 minutes until the mixture does not have the phenomenon of polyvinyl alcohol fiber agglomeration; and finally, adding the water reducing agent into water, stirring uniformly, adding the mixture into the mixture, and stirring for 3-5 minutes to finish the manufacturing process.
The tensile and pressure performance tests of the ultra-high toughness cement-based material and the results are as follows:
(1) an axial compression test is carried out by preparing a prism test block of 70.7mm multiplied by 210mm, and the test result shows that: the average value of the compressive strength of the test block is 74.0 MPa. Due to the existence of the polyvinyl alcohol fibers, the compressive deformability of the test block is enhanced, the ultimate compressive strain reaches 0.01, and the ultimate compressive strain of a common concrete test block is only 0.003-0.004. The test block prepared from the ultra-high toughness cement-based material can keep good integrity in the whole loading process, does not have brittle failure characteristics similar to common concrete, and has good compressive toughness.
(2) A dog-bone-type test block of 330mm multiplied by 60mm multiplied by 13mm is prepared to carry out an axial tension test, multiple fine cracks appear on the test block in the test process, the width of the cracks is 0.05-0.1 mm, the tension strength is 4.5Mpa, the ultimate tensile strain is 2.0% -2.5%, and excellent tension toughness is shown. Compared with the common concrete, the ultimate tensile strain of the common concrete is extremely small and can not be considered, and the tensile failure of the ultra-high toughness cement-based material is particularly and obviously different from that of the common concrete.
The ultra-high toughness cement-based composite material improves the fiber, the matrix and the interface of the fiber and the matrix in the cement-based composite material based on the principle of micromechanics, shows multi-joint cracking during damage, does not have the peeling phenomenon of common concrete, and has good compressive and tensile toughness.
The ultra-high toughness cement-based composite material improves the fiber, the matrix and the interface of the fiber and the matrix in the cement-based composite material based on the principle of micromechanics, shows multi-joint cracking during damage, does not have the stripping phenomenon of the traditional concrete, and has good compression and tension toughness.
The ultrahigh-toughness cement-based composite material has good deformability, has good cooperative deformability with the thin-wall steel column, and can be filled between the thin-wall flange plate and the thin-wall web plate to improve the overall stability of the thin-wall steel column. Meanwhile, the exposed area of the thin-wall steel plate can be reduced by filling the ultrahigh-toughness cement-based composite material, the corrosion rate of the thin-wall steel plate can be effectively reduced, the service life of the combined column is prolonged, and the fire resistance of the combined column is improved.
In the aspect of construction, construction templates required in pouring are reduced, the construction is convenient, and the steel structure column has good social and economic benefits.
The above-mentioned contents are only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited thereby, and any modification made on the basis of the technical idea of the present invention falls within the protection scope of the claims of the present invention.
Claims (8)
1. The utility model provides a thin wall steel combination column of part packing ultra high tenacity cement based composite, a serial communication port, including thin wall flange board (1), two thin wall flange boards (1) parallel arrangement, the centre is connected through thin wall web (2) and is constituted H type structure, the outward flange of two thin wall flange boards (1) passes through tie rod (3) to be connected, fill ultra high tenacity cement based composite (4) between thin wall web (2) and thin wall flange board (1), ultra high tenacity cement based composite can be wrapped up by thin wall flange board (1) and thin wall web (2) and form the column structure.
2. The thin-walled steel composite column partially filled with an ultra-high toughness cement-based composite material according to claim 1, wherein the tie rods (3) are arranged perpendicular to the two thin-walled flange plates (1) and parallel to the thin-walled web (2).
3. The thin-walled steel composite column partially filled with an ultra-high toughness cement-based composite material according to claim 1, wherein the tie rod (3) comprises a plurality of tie rods, which are arranged at equal intervals between the two thin-walled flange plates (1).
4. The thin-walled steel composite column partially filled with the ultra-high toughness cement-based composite material as claimed in claim 3, wherein the tie bars (3) leave a protective layer with a thickness of 30-50 mm from the outer edge of the thin-walled flange plate (1).
5. The thin-walled steel composite column partially filled with an ultra-high toughness cement-based composite material according to claim 1, wherein the ultra-high toughness cement-based composite material (4) comprises cement, fly ash, quartz sand, a water reducing agent, water and polyvinyl alcohol fiber, the cement: fly ash: quartz sand: water: 1 of water reducing agent: 1.5: 1.62: 0.9: 0.025, and the volume ratio of the polyvinyl alcohol fiber is 1.5-2%.
6. The thin-walled steel composite column partially filled with the ultra-high toughness cement-based composite material according to claim 5, wherein the cement, the fly ash and the fine sand are mixed and stirred for 1-2 min at room temperature; adding polyvinyl alcohol fibers, and continuously stirring for 3-5 min until the mixture has no polyvinyl alcohol fiber agglomeration phenomenon; and finally, adding the water reducing agent into water, stirring uniformly, adding the mixture into the mixture, and stirring for 3-5 min to prepare the ultra-high-toughness cement-based composite material.
7. The thin-walled steel composite column partially filled with an ultra-high toughness cement-based composite material according to claim 1, wherein the thin-walled flange plate (1) and the thin-walled web plate (2) in the middle are connected by fillet welding.
8. The thin-walled steel composite column partially filled with an ultra-high toughness cement-based composite material according to any one of claims 1 to 7, wherein the thin-walled steel composite column has a square or rectangular cross-sectional shape.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111851861A (en) * | 2020-07-30 | 2020-10-30 | 华南理工大学 | Partially prefabricated reinforced structure of existing H-shaped steel column and construction process thereof |
| CN113622547A (en) * | 2021-08-13 | 2021-11-09 | 长安大学 | Steel frame recoverable functional strong toughness composite material side force resisting wall |
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| CN109133796A (en) * | 2018-09-25 | 2019-01-04 | 东南大学 | A kind of sprayable superhigh tenacity cement-base composite material and preparation method thereof |
| CN109942257A (en) * | 2019-04-24 | 2019-06-28 | 山东省交通规划设计院 | A kind of road superhigh tenacity cement-base composite material and its preparation method and application |
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2020
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| CN1256735A (en) * | 1997-05-15 | 2000-06-14 | 卡纳姆曼纳克集团公司 | Composite steel/concrete column |
| CN202055393U (en) * | 2011-01-26 | 2011-11-30 | 北京工业大学 | High-strength reinforcement high-ductility fiber reinforced engineered cementitious composite compressed member |
| CN104775565A (en) * | 2015-03-30 | 2015-07-15 | 东南大学 | Steel bar reinforced ECC-steel pipe concrete composite column |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111851861A (en) * | 2020-07-30 | 2020-10-30 | 华南理工大学 | Partially prefabricated reinforced structure of existing H-shaped steel column and construction process thereof |
| CN113622547A (en) * | 2021-08-13 | 2021-11-09 | 长安大学 | Steel frame recoverable functional strong toughness composite material side force resisting wall |
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