A kind of steel pipe foam concrete combination column and job practices thereof
Technical field
The present invention relates to a kind of steel pipe foam concrete combination column and job practices thereof, can be used for the technical field of construction work.
Background technology
Steel pipe foam concrete combination column refers to filled and process concrete in steel pipe, and the composite pillar of concrete cover is set at outer wall of steel pipe.
Steel core concrete column begins to introduce China in middle 1960s, no matter the concrete filled steel tube technology is from theory or technology has had development rapidly in less than 50 years, the concrete filled steel tube pillar that uses in existing industry, civilian construction mostly is greatly simply that the cast portland cement concrete is made in steel pipe.Early stage steel core concrete column has made up the characteristics of the high fragility of concrete greatly to concrete horizontal restrain effect by steel pipe; The concrete of filling in steel pipe has simultaneously limited steel pipe and has produced distortion.Because its combination property is better than simple reinforced concrete post far away, so obtained a large amount of uses.To high stratification, complicated future development, the some shortcomings part of conventional steel concrete column shows gradually along with building.At first, the strength and stiffness of steel core concrete column increase greatly, but its shock resistance well do not improved, and brittle fracture easily occurs the concrete under the repeated action of seismic forces in steel pipe, cause the column bearing capacity to reduce.Secondly, simple steel core concrete column is not in the situation that protect steel pipe, and steel pipe is exposed in air and easily is corroded, and steel pipe also can deform under high-temperature condition simultaneously, and these harm all can affect the stressed of concrete column.
Chinese patent application 200710011988.1 has proposed a kind of fibre reinforced plastic-steel pipe-concrete column, formed by steel pipe, cylindrical fibre reinforced plastic pipe and the concrete that pours into, its design feature is that steel pipe is become by Plate Welding, cylindrical fibre reinforced plastic pipe is at the center of concrete column, then whether fill concrete between two pipes can select fill concrete according to demand in cylindrical fibre reinforced plastic pipe.Make like this concrete column that the advantage of high-bearing capacity, large rigidity, plasticity, good toughness is arranged.
Chinese patent application 201010152109.9 has proposed a kind of steel tube-concrete composite structure, comprises the inside and outside self-compacting concrete that arranges of steel pipe and steel pipe, makes self-compacting concrete become whole with the steel pipe consolidation and sclerosis.Combining structure not only can have advantages of the conventional steel concrete structure like this, can also be beneficial to anti-fire and the decay resistance of steel pipe.
Chinese patent application 201010042608.2 has proposed to fill out hollow steel pipe concrete column of marine sand concrete and preparation method thereof in a kind of, comprises the river sand concrete topping of steel pipe matrix, the outer cast of matrix, the river sand concrete topping of inwall cast and the not desalination marine sand concrete of hollow area cast.Can be to utilize extra large sand in the hollow steel pipe column diameter like this, need not carry out desalting processing, easy construction have solved the problem of coastal area sand and stone resources scarcity.
Chinese patent application 201110386130.X has proposed a kind of cavity type concrete filled steel tube pier stud, formed by steel pipe, interior bag concrete and external wrapping concrete layer, be characterized in steel pipe is arranged perforate, make interior bag concrete and external wrapping concrete layer connect into integral body, can come off by effectively preventing surrounding layer concrete, the anticorrosion and inside that has effectively solved the again simultaneously steel pipe problem of coming to nothing.
Chinese patent application 201110331668.0 has proposed a kind of for coal mine support foam concrete tank shape pier stud and preparation method, comprise thin-wall steel tube and be filled in EPS light high strength concrete in thin-wall steel tube, this pier stud high-strength light, be easy to carrying, non-deformability is strong.
As from the foregoing, present research to the concrete filled steel tube column is mainly the single solution of making for some demand in engineering.And in production reality, the Cement and concrete intended diameter is substantially constant, does not consider that column structure reduces gradually with highly increasing pressure, and is especially particularly remarkable to those structures up to hundred meters; In addition, constant along height of column direction structure rigidity although the anti-seismic performance of steel core concrete column improves a lot than common reinforced concrete post, be unfavorable for giving full play to of structural seismic performance.
Summary of the invention
The object of the present invention is to provide a kind of steel pipe foam concrete combination column; this member is for the defective of conventional steel concrete column; supporting capacity is preferably arranged aspect stress performance; higher antidetonation and non-deformability efficiently solve the problem of pipe corrosion and high temperature deformation simultaneously by the topping of outer wall of steel pipe.In addition, the present invention also provides a kind of job practices of steel pipe foam concrete combination column.
According to steel pipe foam concrete combination column of the present invention, comprise the column body, the column body comprises steel pipe, is cast in the interior foam concrete of steel pipe, is arranged in steel mesh reinforcement and external wrapping concrete layer on outer wall of steel pipe, be connected with the flange bellmouth by flange between steel pipe, be placed with pad between flange and flange bellmouth.In addition, as required, what the column body can be for uniform section or variable cross-section.
Foam concrete in the present invention can be fly ash foam concrete, its composition comprises: foaming agent, cement, flyash, lime, gypsum and compound additive, wherein the mass ratio of flyash and cement is 2.2-2.7, and compound additive is comprised of C-3 water reducing agent and expansion agent.Preferred match ratio is flyash 56%~60%, lime 12%~15%, gypsum 3%~5%, portland cement 22%~25%, compound additive 2%~3%, aqueous foaming agent 1.2mL/kg, ratio of water to material 0.41, and in compound additive, the mass ratio of C-3 water reducing agent and expansion agent is 1: 1.
Foam concrete in the present invention can also be ceramsite foam concrete, its composition comprises: foaming agent, cement, haydite, flyash, silicon ash, gypsum and compound additive, wherein the mass ratio of haydite and cement is 1.1-1.4, and compound additive is comprised of C-3 water reducing agent and expansion agent.Preferred match ratio is cement 28%~32%, haydite 35%~40%, flyash 10%~12%, silicon ash 10%~15%, gypsum 3%~5%, compound additive 2%~3%, aqueous foaming agent 0.15%, ratio of water to material 0.21, and in compound additive, the mass ratio of C-3 water reducing agent and expansion agent is 1: 1.Preferably, haydite is the leca of 1.5~4mm level or the low-density haydites of book structure of 600 grades~900 grades.
On the other hand, the job practices according to construction steel pipe foam concrete combination column of the present invention comprises the following steps:
(1) prefabricated steel pipe: steel pipe adopts spiral welded steel pipe or rolls the straight-seam pipes that bed rolls, with the steel mesh reinforcement colligation or be welded on the outer wall of steel pipe;
(2) docking steel pipe: the mouth of pipe place of the flange bellmouth being welded or is spliced to steel pipe one end, flange is inserted in or is spliced to the other end of steel pipe, and the mouth of pipe is outwards twisted, then place pad and complete docking by connecting bolt in the middle of the flange of adjacent steel pipe and flange bellmouth;
(3) build foam concrete: will put in place to the steel pipe frame that connects is vertical, and then build foam concrete in steel pipe, and adopt a high position to leave without vibrate method or pumping-up method when building and build from the mouth of pipe;
(4) build external wrapping concrete: external wrapping concrete is cast on the steel mesh reinforcement of outer wall of steel pipe;
Foam concrete wherein can be fly ash foam concrete, match ratio is flyash 56%~60%, lime 12%~15%, gypsum 3%~5%, portland cement 22%~25%, compound additive 2%~3%, aqueous foaming agent 1.2mL/kg, ratio of water to material 0.41, perhaps
Foam concrete can be ceramsite foam concrete, match ratio is cement 28%~32%, haydite 35%~40%, flyash 10%~12%, silicon ash 10%~15%, gypsum 3%~5%, compound additive 2%~3%, aqueous foaming agent 0.15%, ratio of water to material 0.21
Above-mentioned compound additive is that C-3 water reducing agent and the expansion agent of 1: 1 forms by mass ratio;
Wherein the preparation process of foam concrete is:
First dried gathering materials stirred 2 minutes, then water and compound additive are added in the good material of dry mixing stirred 3~5 minutes, will dilute at last good foaming agent and join and stirred in slurry 3~5 minutes, build after testing degree of mobilization.
The present invention has the following advantages:
Steel pipe foam concrete combination column proposed by the invention, kept the strong advantage of the whole weight capacity of conventional tube concrete pillar, in order to make up the shortcoming that conventional steel concrete column fragility is large, anti-seismic performance is not enough, ordinary concrete in steel pipe is replaced with foam concrete, greatly improved ductility and the shock resistance of structure; The foam concrete that the present invention fills in steel pipe can reduce the concrete shrinkage strain of steel duct, effectively reduces the contraction that occurs in the steel pipe phenomenon of coming to nothing.
The foam concrete that the present invention uses belongs to inorganic material, and is non-combustible, so have good refractoriness, uses and can greatly improve its fireproof performance in building; Foam concrete density is little, quality is light, modulus of elasticity is low, and the seismic forces that bears under seismic loading is less, and the transmission speed of shock wave is slower, and the cycle of shake certainly of structure is long, and the absorption of impact energy is fast, thereby has good damping effect.
Foam concrete of the present invention is cast in can be avoided in steel pipe contacting with the direct of air well, prevents that it from because of the suction destruction that rough surface, porous cause, strengthening the durability of column; Foam concrete pumpability in work progress is good, and this makes it be applicable to on-the-spot filling of large volume and builds engineering; Foam concrete of the present invention can utilize industrial residue in a large number, and is cheap, and very high economic benefit is arranged.
The present invention can arrange different foaminesses to the differing heights concrete according to the difference of differing heights cylinder design bearing capacity, satisfies the design needs and greatly reduces costs simultaneously, increases economic efficiency.
The present invention vertically can carry out gradual change along the steel pipe caliber, can according to the design needs, select different post footpaths at different positions, in order to improve the bearing capacity of certain a part or whole part like this, simultaneously the material at the low position of bearing capacity demand be can reduce again, economy, timesaving purpose reached.
The invention reside in the shape that can change the column body by the shape that changes steel pipe, so both can satisfy the needs of design, also can take into account the attractive in appearance of moulding; Complete each intersegmental connection of column by adpting flange, the steel pipe docking is simple, quick, avoids welding between steel pipe, better improves the safety of column; Concreting topping outside steel pipe prevents steel pipe generation corrosion and high temperature deformation; The outer steel mesh reinforcement of steel pipe increases outer surface of steel tube and concrete tackness, makes the concrete cover difficult drop-off; Steel pipe foam concrete combination column of the present invention has also been avoided complicated arrangement of reinforcement process, makes work progress more quick.
Description of drawings
Fig. 1 is the cross sectional representation of round steel pipe foam concrete combination column.
Fig. 2 is the cross sectional representation of rectangular steel tube foam concrete combination column.
Fig. 3 is the cross sectional representation of polygonal steel pipe foam concrete combination column.
Fig. 4 is the present invention's vertical form steel mesh reinforcement structural representation used.
Fig. 5 is the present invention's flat form steel mesh reinforcement structural representation used.
Fig. 6 is vertical uniform section structural representation of Fig. 1.
Fig. 7 is the longitudinal variable cross-section structural representation of Fig. 1.
Fig. 8 is the floor map of flange.
Fig. 9 is the floor map of flange bellmouth.
Figure 10 is the sectional drawing of A-A line in Fig. 9.
Figure 11 is the layout schematic diagram of flange connections B.
Reference numeral:
The 2-steel pipe; 3-foam concrete; The 4-steel mesh reinforcement; 5-external wrapping concrete layer; The 6-flange; 7-flange bellmouth; The 8-pad; The 9-connecting bolt; The 10-nut.
The specific embodiment
For making the purpose, technical solutions and advantages of the present invention clearer, hereinafter in connection with accompanying drawing, embodiments of the invention are elaborated.Need to prove, in the situation that do not conflict, the embodiment in the application and the feature in embodiment be any combination mutually.
Accompanying drawing has selectively been showed the structural representation of preferred enforcement of arriving involved in the present invention, below in conjunction with the detailed explanation of accompanying drawing technical scheme of the present invention.In addition, except as otherwise noted outside, in the present invention, the ratio of each component is mass ratio.
To shown in Figure 7, steel pipe foam concrete combination column described in the invention comprises the column body as Fig. 1, and body comprises steel pipe 2, is cast in the interior foam concrete 3 of steel pipe 2, is arranged in steel mesh reinforcement 4 and external wrapping concrete layer 5 on outer wall of steel pipe.Wherein, the steel pipe foam concrete combination column that has shown respectively circular cross-section, square-section and polygonal cross-section in Fig. 1-3.As shown in Fig. 4-5, the steel mesh reinforcement 4 that is arranged on outer wall of steel pipe can be the arrangement of vertical form peace form.
Because the load that steel pipe foam concrete combination column bears from top to bottom is increasing, so size according to its carrying, the cross-sectional sizes of steel pipe foam concrete combination column can increase from top to bottom gradually, has so not only saved material, and can also give full play to the supporting capacity of structure.As shown in Fig. 6 and 7, wherein shown respectively the steel pipe foam concrete combination column of uniform section and variable cross-section.
As shown in Fig. 8-10, wherein shown respectively flange 6 and the flange bellmouth 7 of the steel pipe that connects up and down.Referring to Figure 11, wherein shown the layout schematic diagram of flange connections B.Be placed with pad 8 between the flange bellmouth 7 of top steel pipe and the flange 6 of bottom steel pipe, and be connected connection with nut by connecting bolt 9.The upper end of bottom steel pipe is provided with the hole enlargement mouth, is used for the lower end that holds the top steel pipe.
Foam concrete of the present invention can be fly ash foam concrete, and its composition comprises: foaming agent, cement, flyash, lime, gypsum and compound additive.The coefficient of foaming of foaming agent is not less than 20, and the depression distance of the foam after a hour of bubbling is less than 10mm, and measure less than 80ml the Qinshui, the maintenance foam stabilization.Cement can adopt and prevent sedimentation, Qinshui and the high-grade early strength silicate, aluminium sulfate or the ferrous aluminate cement that improve early age strength of concrete.Flyash has the double action of gathering materials and generating cementitious material.Lime should adopt quicklime.Gypsum plays the exciting agent effect, its CaSO
4Mass content should less than 65%, can not increase the early strength of foam concrete.Admixture should have early strength, diminishing and the minimizing contraction of raising.Through for a long time constantly test, when finding that mass ratio when flyash and cement is at 2.2-2.7, steel pipe foam concrete combination column has compressive strength and the bending rigidity of optimum.Preferred match ratio is: flyash 56%~60%, lime 12%~15%, gypsum 3%~5%, portland cement 22%~25%, compound additive 2%~3%, aqueous foaming agent 1.2mL/kg, ratio of water to material 0.41.
Foam concrete of the present invention can also be ceramsite foam concrete, its composition comprises: foaming agent, cement, haydite, flyash, silicon ash, gypsum and compound additive, flyash and silicon ash are mainly used in generating cementitious material, and haydite belongs to mainly and gathers materials.Through for a long time constantly test, when finding that mass ratio when haydite and cement is at 1.1-1.4, steel pipe foam concrete combination column has compressive strength and the bending rigidity of optimum.The preferred quality mixture ratio of each material is: cement 28%~32%, haydite 35%~40%, flyash 10%~12%, silicon ash 10%~15%, gypsum 3%~5%, compound additive 2%~3%, aqueous foaming agent 0.15%, ratio of water to material 0.21.Haydite in ceramsite foam concrete of the present invention can be selected leca and/or haydites of book structure, the foam concrete mobility of wherein mixing leca is better than the foam concrete that mixes haydites of book structure, but leca foam concrete compressive strength will be lower than haydites of book structure foam concrete.The small particle diameter haydite of the preferred 1.5~4mm level of leca, preferred 600 grades~900 grades low-density ceramsites of haydites of book structure.
The invention described above foam concrete compound additive used is comprised of C-3 water reducing agent and expansion agent, mixes at 1: 1 in mass ratio.
Steel pipe in the present invention will satisfy following requirement: if select its external diameter of round steel pipe should not be less than 100mm, its thickness of steel pipe should not be less than 5mm, its flakiness ratio should be got between 90~120 simultaneously, like this pouring quality of guarantee pipe inner concrete and the welding quality of steel pipe.If select its external diameter of rectangular steel pipe should not be less than 100mm, its thickness of steel pipe should not be less than 5mm, and the depth-width ratio in cross section should not be greater than 2; Simultaneously when the diameter of steel pipe during greater than 800mm, be preferably in steel pipe inner wall weld stud or longitudinal stiffener, to increase the bonding of tube wall and foam concrete, prevent from causing because caliber is excessive foam concrete to produce larger contraction, and can effectively prevent the flexing of steel pipe walls.
The cuff coefficient in its cross section of steel pipe foam concrete column of the present invention should not less than 0.5, brittle fracture occur to prevent column.
Pipe inner foam concrete of the present invention can adopt vertical craft to water the method for smashing, a high position leaves without vibrating method and pumping-up method etc.; The proportioning of foam concrete still should be selected rational concrete slump according to different casting methods except satisfying mechanical performance index.Leave without vibrating method and pumping-up method for a vertical high position, coarse aggregate size can adopt 5~30mm, and water/binder ratio is not more than 0.45, and the slump is not less than 150mm; Water for manual the method for smashing, coarse aggregate size can adopt 10~40mm, and water/binder ratio is not more than 0.42, and the slump is not less than 20~40mm.
Foam concrete of the present invention is in the preparation first by the proportioning chosen material, and the cement for preparing, gather materials etc. was carried out dry mixing 2 minutes; Add in the good material of dry mixing with water with by the compound additive that water reducing agent, expansion agent form again and stirred 3~5 minutes; To dilute at last good foaming agent and join and stirred in slurry 3~5 minutes, build after the test degree of mobilization.
External wrapping concrete of the present invention can be plain concrete, also can be according to the difference of pillar environment of living in, and the different choice fibrous concrete to topping requires comprises: steel fibrous concrete, glass reinforced concrete and synthetic fiber concrete.
Steel pipe foam concrete of the present invention adopts adpting flange to complete each intersegmental connection when segmentation is built, and flange connects easy to use, and intensity is high, can bear larger pressure, simultaneously good airproof performance.
In implementation process, at first carry out steel pipe manufacturing, preferentially select spiral welded steel pipe, also can adopt and roll the straight-seam pipes that bed rolls.Then as shown in Fig. 4,5 with the steel mesh reinforcement colligation on steel pipe, also can be welded on outer wall of steel pipe in the situation that steel pipe walls is thicker.
Connection between steel pipe connects by flange to be completed.At first, the flange bellmouth is welded or is spliced to the mouth of pipe place of steel pipe one end, flange is inserted in or splices the steel pipe other end, and the mouth of pipe is outwards twisted; Then place pad and complete docking by connecting bolt in the middle of flange and flange bellmouth, bolton is passed through in splicing place of flange when selecting the splicing flange.Adpting flange can be selected the form shown in Fig. 8,9, also can select other forms in conjunction with demand.
To put in place to the steel pipe frame that connects is vertical, and then build foam concrete in steel pipe, and can select when building to build from the mouth of pipe, and leave without vibrating method and pumping-up method as a high position, the mouth of pipe is built the constant situation of foaming degree that generally is applicable to foam concrete; Also can be chosen in the place's punching of steel pipe differing heights builds, water as vertical craft the method for smashing, it is generally in the situation that cylinder deadweight is had relatively high expectations that punching is built, do not change the cylinder bearing capacity according to design requirement, section is used the foam concrete of different foaming degree at various height, can alleviate the body deadweight in the situation that do not affect bearing capacity like this.External wrapping concrete is cast on the steel mesh reinforcement of steel pipe periphery as shown in Figure 1, and thickness should so both can play the protective effect to steel pipe between 3~8cm, can not reduce again whole toughness and ductility.
Although the disclosed embodiment of the present invention as above, the embodiment that described content just adopts for the ease of understanding the present invention is not to limit the present invention.Technician in any the technical field of the invention; under the prerequisite that does not break away from the disclosed spirit and scope of the present invention; can do any modification and variation what implement in form and on details; but scope of patent protection of the present invention still must be as the criterion with the scope that appending claims was defined.