CN114108806A

CN114108806A - A prefabricated steel tube UHPC composite hollow column-section steel beam composite frame

Info

Publication number: CN114108806A
Application number: CN202111433118.XA
Authority: CN
Inventors: 葛文杰; 汤蓉; 韩沐阳; 杨岩; 蒋洪波; 孙传智; 严卫华; 葛越; 姚山
Original assignee: Yangzhou University
Current assignee: Yangzhou University
Priority date: 2021-11-29
Filing date: 2021-11-29
Publication date: 2022-03-01

Abstract

The invention discloses a prefabricated UHPC composite hollow column-shaped steel beam composite frame of a prefabricated steel tube, which combines the respective characteristics of a reinforced concrete frame structure and a steel frame structure to introduce a prefabricated assembled steel tube UHPC composite hollow column-shaped steel beam composite frame. The frame column is made of steel tube UHPC composite hollow column, and the triple restraint of inner and outer double steel tubes and stirrups greatly improves the bearing capacity and seismic performance of the frame column. The frame beam adopts the section steel sold in the market. Compared with the concrete beam, the section steel beam has a lighter weight and better ductility. The use of light section steel as the frame beam is conducive to reducing the overall weight of the structure, and is not conducive to reducing the frame column. It is of great help to increase the usable area of the building.

Description

Prefabricated assembled steel pipe UHPC composite hollow column-steel beam combined frame

Technical Field

The invention belongs to the field of steel-concrete composite structures, and particularly relates to a prefabricated steel pipe UHPC composite hollow column-steel beam composite frame.

Background

Concrete and steel are two most important building materials for forming modern building structures, and the improvement of the performance of the two materials and the improvement of the combination mode of the two materials promote the continuous development and innovation of the building structures from components to systems. The steel-concrete composite structure is a novel structural form developed on the basis of a steel structure and a reinforced concrete structure, can fully utilize the respective advantages of steel and concrete materials, and is widely applied to multiple fields of high-rise and super high-rise buildings, long-span structures, bridge structures, underground engineering, building reinforcement and reconstruction and the like. As an important direction of building innovation, the steel-concrete composite structure will play an increasingly important role in the development process of civil engineering industry in China.

Ultra-High Performance Concrete (UHPC) is an Ultra-High strength cement-based composite material prepared based on the theoretical principle of maximum bulk density. The UHPC removes coarse aggregate, the cement matrix is uniform and compact, and the cement has the characteristics of high strength, good toughness, good durability and the like. When the UHPC is applied to the composite column, the bearing capacity, toughness, durability and other related properties of the composite column can be effectively improved. The requirement of the building structure on the working performance of the concrete material is met.

At present, the research of the assembly type building is one of the main research subjects of building researchers, and the assembly type building has the following main advantages:

(1) and the construction period is shortened:

compared with the traditional cast-in-place mode, the construction steps of the traditional process are saved, the construction period is effectively shortened, and the construction efficiency is obviously improved.

(2) The labor cost is reduced:

through mechanized assembly construction mode, fully compensate the short slab of traditional construction, not only reduced the site operation personnel, also alleviated managers's operating pressure, labour cost greatly reduced.

(3) The safety is improved:

the cross working face is obviously reduced in the application of the fabricated building, only hoisting and installing workers need to be equipped on site, and management personnel are relatively reduced, so that the potential safety hazard of a construction site can be effectively reduced, and reliable safety guarantee is provided for related construction personnel.

At present, researchers at home and abroad have more researches on steel tube confined reinforced concrete columns, and the researches show that the bearing capacity, the seismic performance, the ductility and other related performances of the steel tube confined reinforced concrete columns are effectively improved compared with those of common reinforced concrete columns. The steel tube confined concrete column does not need a template when concrete is poured in the prefabrication stage, the steel tube can be directly used as a plate, and compared with a common template, the steel tube used as the template can better bear construction load. If the common concrete in the steel pipe is replaced by UHPC, the steel pipe UHPC composite hollow column is prepared and used as a composite column, and the bearing capacity, toughness, durability and other related properties of the composite column can be effectively improved. Thereby effectively improving the comprehensive performance of the frame structure.

Disclosure of Invention

The invention provides a prefabricated assembly type steel pipe UHPC composite hollow column-shaped steel beam combined frame aiming at the problems that a common reinforced concrete frame structure has long construction period in site vertical mould pouring, poor maintenance condition, large human resource consumption, poor structural durability, poor fire resistance and corrosion resistance of a steel structure frame and the like, and aims to improve the comprehensive performance of the frame structure and shorten the construction period.

The technical solution for realizing the invention is as follows: the invention combines the characteristics of a reinforced concrete frame structure and a steel frame structure, and introduces a prefabricated assembled steel pipe UHPC composite hollow column-steel beam combined frame. The frame column adopts a steel pipe UHPC composite hollow column, and the bearing capacity, the anti-seismic performance and other related performances of the frame column are greatly improved by utilizing triple constraints of an inner steel pipe, an outer steel pipe and a stirrup. The frame roof beam chooses the shaped steel of selling on the market for use, and its dead weight of shaped steel roof beam is lighter for the concrete beam, and has better ductility, adopts the light shaped steel as the frame roof beam to be favorable to alleviateing the holistic dead weight of structure, has great help to reducing the cross sectional dimension of frame post, increase building usable floor area.

Compared with the prior art, the invention has the remarkable advantages that:

the invention combines the advantages of the concrete structure and the steel structure, and utilizes the excellent performance of the UHPC to improve the comprehensive performance of the frame. The composite column adopts a steel pipe constraint UHPC combined structure formed by pouring UHPC into a steel pipe, the steel pipe laterally constrains the UHPC, the compressive strength of the core UHPC is improved, the toughness and the durability are further improved, the advantages of the UHPC can be furthest exerted, and the composite column has good effects on reducing the sectional area of a component and optimizing the structural level. The frame beam adopts the shaped steel beam, so that the construction period is shortened, and the self weight of the structure is reduced. According to the invention, no template is required to be manufactured when the UHPC is poured, the UHPC is directly poured in the steel pipe, the construction period is greatly shortened, and the loss of manpower and material resources is also saved.

Drawings

FIG. 1 is a schematic diagram of the underlying framework of the present invention.

FIG. 2 is a schematic view of an interlayer frame of the present invention.

Fig. 3 is a top level frame diagram of the present invention.

FIG. 4 is a schematic view of bottom and middle layer frame posts of the present invention.

Fig. 5 is a top frame column schematic of the present invention.

Fig. 6 is a cross-sectional view a-a of fig. 4 of the present invention.

FIG. 7 is a schematic view of a steel plate embedment of the present invention.

FIG. 8 is a schematic view of a column shoe according to the present invention

Fig. 9 is a schematic view of a post coupler of the present invention, with a front view on the left and a top view on the right.

Figure 10 is a cross-sectional view of a top column beam column connection node of the present invention.

Fig. 11 is a schematic view of the top pillar beam column connection node of the present invention.

Fig. 12 is a connection diagram of a column shoe and a foundation of the present invention.

FIG. 13 is a schematic view of the bottom pillar structure of the present invention.

FIG. 14 is a schematic view of the installation of the bottom socle stiffener structure of the present invention.

Figure 15 is a schematic view of the installation of the post coupler of the present invention.

Fig. 16 is an overall installation view of the present invention.

Detailed Description

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 only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without inventive step, are within the scope of the present invention.

It should be noted that all the directional indicators (such as upper, lower, left, right, front and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indicator is changed accordingly.

In the present invention, unless otherwise expressly specified or limited, the terms "connected," "secured," and the like are to be construed broadly, e.g., "secured" may be fixedly connected, releasably connected, or integral; "connected" may be mechanically or electrically connected. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In addition, the technical solutions in the embodiments of the present invention may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination of technical solutions should not be considered to exist, and is not within the scope of the claimed invention.

The following further introduces specific embodiments, technical difficulties and inventions of the present invention with reference to the design examples.

Referring to fig. 1 to 11, a prefabricated steel pipe UHPC composite hollow column-steel beam combined frame is composed of a bottom layer frame, a plurality of middle layer frames and a top layer frame, which are sequentially arranged from bottom to top.

The bottom layer frame, the middle layer frame and the top layer frame all comprise a plurality of composite columns and a plurality of section steel beams 15 fixed on the composite columns.

The composite column comprises an outer steel pipe 1, stirrups 2, longitudinal ribs 3, an inner steel pipe 4, UHPC5, a flange plate 6, a high-strength connecting steel pipe 8 and beam column connecting plates 9, wherein the inner steel pipe 4 is arranged in the outer steel pipe 1, an annular cavity is reserved between the inner steel pipe and the outer steel pipe, a plurality of longitudinal ribs 3 are distributed in the annular cavity, the longitudinal ribs 3 are connected through the stirrups 2, UHPC5 is poured in the annular cavity, the high-strength connecting steel pipe 8 is fixed on the outer side of the outer steel pipe 1, and a plurality of beam column connecting plates 9 are symmetrically distributed and fixed on the outer wall of the high-strength connecting steel pipe 8 and used for fixing the steel beam 15. The outer steel pipe 1 is further provided with a flange 6, and the flange 6 is used for connecting different layers of composite columns through bolts 10. A plurality of stiffening ribs 7 are distributed on the outer steel pipe 1, and the bottom surfaces of the stiffening ribs 7 are fixed on the flange 6.

The column base of the bottom composite column positioned at the bottom layer is also provided with a steel plate embedded part 11, an embedded part bottom shear key 12 and an embedded part bottom anchoring steel bar 13, and the embedded part bottom anchoring steel bar is fixed with a reinforced concrete foundation 16 through foundation bolts 14.

The top surface of the composite column at the top layer is also provided with a column steel cover plate 17.

The UHPC5 comprises the following components in parts by weight: 10 to 50 percent of cement, 20 to 30 percent of quartz sand, 12 to 12.5 percent of silica fume, 0 to 35 percent of fly ash, 15 to 20 percent of mineral powder, 15 to 20 percent of water and 0.2 to 2.5 percent of water reducing agent, wherein the steel fiber accounts for 1.5 to 2.5 percent of the volume doping amount of the UHPC 5.

1 the maximum grain size of the quartz sand is not more than 0.3 mm.

2, the steel fiber is selected to achieve the effect of strengthening and toughening, thereby improving the tensile capability of the cement-based material. The steel fiber used is round and straight, the diameter is between 0.2 mm and 0.4 mm, the length is between 12 mm and 15 mm, and the tensile strength is about 2800 MPa.

3 the water reducing agent is a polycarboxylic acid high-performance water reducing agent.

The preparation method of the UHPC comprises the following steps: sequentially pouring cement, quartz sand, silica fume, mineral powder and fly ash which are weighed according to a certain proportion into a stirrer, and dry-stirring for 3 min to fully mix the materials; then, uniformly mixing the weighed water and the high-efficiency water reducing agent, pouring the mixture into a stirrer, and slowly rotating for 3 min and then rapidly rotating for 2 min; after the fluidity is good, slowly adding the steel fiber, stirring for 5 min to uniformly disperse the steel fiber, and discharging.

All the material usage and relevant dimensions need to be calculated and selected according to the requirements of the actual engineering.

With reference to fig. 12 to 16, the assembling method of the prefabricated assembly type steel pipe UHPC composite hollow column-steel beam combined frame includes the following steps:

step 1, binding a composite column reinforcement cage, wherein the reinforcement cage is composed of stirrups 2 and longitudinal reinforcements 3.

And 2, placing the reinforcement cage into an annular cavity formed by the inner steel pipe 4 and the outer steel pipe 1.

And 3, filling the UHPC5 into the annular cavity, and maintaining the UHPC5 to meet the strength requirement.

And 4, welding a flange plate 6 on the outer steel pipe of the composite column, and reserving bolt holes on the flange plate 6. And the beam column connecting plate 9 is welded on the outer steel pipe at the top of the top layer column.

And 5, welding a stiffening rib 7 between the flange 6 and the outer steel pipe 1 of the composite column.

And 6, welding a flange 6, a stiffening rib 7 and a beam-column connecting plate 9 on the high-strength connecting steel pipe 8 according to the requirement.

And 7, transporting the required various materials and the composite column to a construction site.

And 8, pouring a foundation, embedding a steel plate embedded part, and installing the composite column of the bottom layer in place by using the foundation bolts 14.

And 9, mounting a layer of section steel beam 15.

And step 10, installing each layer of composite columns and frame beams through bolts 10.

In conclusion, the invention consists of the composite column and the section steel beam, and has the structural key points that: the inner and outer double steel pipe combination is used for placing a steel reinforcement cage between the double steel pipes and injecting UHPC, and the steel pipes and the stirrups are used for restraining the UHPC to improve the bearing capacity, toughness, shock resistance and other related performances of the composite column. The frame beam is made of the section steel beam, so that the self weight is light, the ductility is good, and good performance is provided for reducing the self weight of the structure and the section size of the composite column. The length of the longitudinal ribs extending into the upper column and the lower column at the splicing part of the column ends needs to meet the requirement of the overlapping length specified by the specification. The section steel beam, the inner steel tube, the outer steel tube, the reinforcement ratio and the like are calculated according to the actual required load bearing requirement.

The invention aims to provide a prefabricated assembled steel pipe UHPC composite hollow column-steel beam combined frame which can be widely applied to the field of buildings, and the bearing capacity and the durability of a composite column are improved by utilizing the advantages of high strength and durability of UHPC and matching with the constraint force of a steel pipe. The structural dead weight is reduced by adopting the section steel beam, and a structural system is optimized. The construction speed is effectively improved by utilizing factory prefabrication and field splicing, and the engineering quality is improved. The invention can be used as a load-bearing structure of a building structure.

Claims

1. a prefabricated prefabricated steel pipe UHPC composite hollow column-section steel beam composite frame, is characterized in that: by the bottom frame, some middle layer frames and the top frame that are arranged successively from bottom to top, the bottom frame, the middle layer frame, The top frame includes a plurality of composite columns and a plurality of profiled steel beams (15) fixed on the composite columns.

2. The prefabricated prefabricated steel pipe UHPC composite hollow column-steel beam composite frame according to claim 1, wherein the composite column comprises an outer steel pipe (1), a stirrup (2), a longitudinal reinforcement (3), an inner Steel pipe (4), UHPC (5), flange plate (6), high-strength connecting steel pipe (8), beam-column connecting plate (9), inner steel pipe (4) is set in outer steel pipe (1), and there is a gap between the two. There is an annular cavity, a number of longitudinal bars (3) are arranged in the annular cavity, the longitudinal bars (3) are connected by stirrups (2), and UHPC (5) is poured in the annular cavity, and high-strength connecting steel pipes (8) Fixed on the outer side of the outer steel pipe (1), a plurality of beam-column connecting plates (9) are symmetrically distributed and fixed on the outer wall of the high-strength connecting steel pipe (8) for fixing the profiled steel beam (15); the outer steel pipe (1) is also provided with There are flanges (6), which are used to connect and realize the connection of composite columns of different layers; a number of stiffeners (7) are distributed on the outer steel pipe (1), and the bottom surface of the stiffeners (7) is fixed on the above flanges plate (6).

3. The prefabricated prefabricated steel pipe UHPC composite hollow column-section steel beam composite frame according to claim 2, characterized in that: the column foot of the bottom composite column located on the bottom layer is also provided with a steel plate embedded part (11), a pre-embedded part (11). The shear key (12) at the bottom of the part and the anchoring steel bar (13) at the bottom of the embedded part are fixed with the reinforced concrete foundation (16) through the anchor bolts (14).

4. The prefabricated steel pipe UHPC composite hollow column-steel beam composite frame according to claim 3, characterized in that: the top surface of the composite column located on the top layer is further provided with a column steel cover plate (17).

5. The prefabricated prefabricated steel pipe UHPC composite hollow column-steel beam composite frame according to claim 4, characterized in that: the above-mentioned UHPC (5) is composed of cement, quartz sand, silica fume, fly ash, Mineral powder, steel fiber, water and water reducing agent, the weight ratio of each component is: cement 10%-50%, quartz sand 20%-30%, silica fume 12%-12.5%, fly ash 0%-35% %, mineral powder 15%-20%, water 15%-20%, water reducing agent 0.2%-2.5%, of which steel fiber accounts for 1.5%-2.5% by volume of UHPC (5).

6. The prefabricated prefabricated steel pipe UHPC composite hollow column-section steel beam composite frame according to claim 5 is characterized in that:

1) The maximum particle size of quartz sand does not exceed 0.3 mm;

2) The steel fibers used are round and straight, with a diameter of 0.2 to 0.4 mm, a length of 12 to 15 mm, and a tensile strength of 2800 MPa;

3) The water reducing agent is a polycarboxylate high-performance water reducing agent.

7. The preparation method of the prefabricated prefabricated steel pipe UHPC composite hollow column-section steel beam composite frame according to any one of claims 1 to 6, characterized in that:

Step 1. Bind the composite column reinforcement cage, the reinforcement cage is composed of stirrups (2) and longitudinal reinforcements (3);

Step 2. Put the reinforcement cage into the annular cavity formed by the inner steel pipe (4) and the outer steel pipe (1);

Step 3. Fill the UHPC (5) into the annular cavity, and maintain the UHPC (5) to meet the strength requirements;

Step 4. Weld the flange (6) on the outer steel pipe of the composite column, and reserve bolt holes on the flange (6);

The welded beam-column connecting plate (9) of the steel pipe outside the top of the top column and column;

Step 5. Weld the stiffener (7) between the flange (6) and the outer steel pipe (1) of the composite column;

Step 6. Weld the flange (6), the stiffener (7), and the beam-column connecting plate (9) on the high-strength connecting steel pipe (8) as required;

Step 7. Transport all required materials and composite columns to the construction site;

Step 8, pouring the foundation, and pre-embedding the steel plate embedded parts, and installing the composite column on the bottom layer in place by using the anchor bolts (14);

Step 9, install a layer of steel beams (15);

Step 10. Install each layer of composite columns and frame beams with bolts.