CN103539407B - Concrete for steel reinforced concrete combined structure with C160 strength level - Google Patents
Concrete for steel reinforced concrete combined structure with C160 strength level Download PDFInfo
- Publication number
- CN103539407B CN103539407B CN201310491758.5A CN201310491758A CN103539407B CN 103539407 B CN103539407 B CN 103539407B CN 201310491758 A CN201310491758 A CN 201310491758A CN 103539407 B CN103539407 B CN 103539407B
- Authority
- CN
- China
- Prior art keywords
- concrete
- cement
- water
- quality
- content
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
The invention discloses concrete for a steel reinforced concrete combined structure with C160 strength level. The concrete is composed of cement, fine aggregate, coarse aggregate, water, a concrete super plasticizer, a defoaming agent, silica fume, fly ash and an activator according to a ratio of 468:782:1116:108:16:1:65:117:6. The preparation method is as follows: firstly, uniformly mixing the concrete super plasticizer and the activator in weighed water to obtain a mixture, sequentially adding 1/3 of total dosage of the fine aggregate and the mixture in a stirring machine according to a weight ratio, and stirring; adding 1/3 of total dosage of the coarse aggregate and the mixture and stirring; and adding the cement, the silica fume and the fly ash, and stirring; and adding the defoaming agent and the rest mixture, stirring and discharging. The concrete can greatly perfect the adhesive property between section steel and the concrete under a natural state, effectively play the respective mechanical properties and mutual cooperative working performance of the steel and the concrete and greatly improve the carrying capacity, application performance and durability of the structural member, thereby having good high-volume stability and economical efficiency.
Description
Technical field
The invention belongs to building material technical field, relating to a kind of is the super high strength high performance concrete of C160 for reinforced concrete composite structure strength grade.
Background technology
The invention of portland cement in 1824 makes concrete technology obtain to develop rapidly, and its consumption is big, the scope of application extensively may occupy the first in the world.Although concrete is a kind of traditional manufactured construction materials, but because it has the continuous progress of superiority (abundant raw material, production technique simple, cost performance advantages of higher) and the concrete material science and technology do not replaced, concrete has become the main body of civil engineering work material, also will be one of indispensable main material in the civil engineering work and nation-building in future.Simultaneously, along with the continuous expansion of city size, being on the increase of population, the continuous rising of land price, harshization of the residing environment of building, the continuous progress of Building technology and rapid development of economy, buildings is more and more in the air, extend in underground and water, namely (surpassing) heightization is built, (surpassing) is large across change, underground, the development of lightweight and heavy type structure, especially steel reinforced concrete structure is in superelevation, super-span, underground, marine or change under water, the application of the novelty such as lightweight or megaplex engineering field, also more and more higher to the requirement of this material of construction of concrete.Therefore, the research and practice of concrete superelevation strengthening and super-durable will become the development trend in this field.
Reinforced concrete composite structure (being called for short SRC structure) is a kind of principal mode of steel-concrete combined structure, due to series of advantages such as its supporting capacity is high, rigidity is large, ductility is good, anti-seismic performance is superior, fire retardant anticorrosion, constructabilities, be applied to greatly across, heavy type structure more and more widely, underground, or the high level of marine engineering and earthquake/typhoon zone and high-rise building under water.Compared with steel construction, SRC structure can save great deal of steel, strengthens section rigidity, overcomes the shortcoming such as steel structure fire-resistant, erosion resistance and poor durability and easy flexing unstability, the ability of steel is fully played; Compared with ordinary reinforced concrete structure (abbreviation reinforced concrete structure), steel reinforced concrete structure can reduce the sectional dimension of component, the space shared by reduction, thus increases building usage space; In construction, the Steel Skeleton of steel reinforced concrete structure itself can be used as the skeleton that concrete hangs mould, sliding formwork, not only enormously simplify formwork engineering, still bears the supporting system of whole construction loads (comprising extension, sliding formwork and institute's pouring concrete); In addition, because SRC structure has globality by force, the advantages such as good working ductility, can improve the brittleness of Steel Concrete sheared destruction greatly, and the anti-seismic performance of structure is significantly improved, and supporting capacity and ductility are all greatly improved than reinforced concrete structure.Therefore, in Japan and the developed country such as American-European, the SRC structure with good anti-seismic performance has become a kind of generally acknowledged novel earthquake-proof structural system, and with steel construction, timber structure, skeleton construction be called four macrostructures.China is also the country of earthquake more than, and most area is seismic region, and part is positioned at highlight lines and frequently occurred earthquake district, promotes SRC structure just have very important realistic meaning in these areas.Therefore, SRC structure has boundless application prospect in China, especially along with the successful Developing Application of the continuous enhancing of China's economic strength and (surpassing) high-strength steel and (surpassing) high-strength high-performance concrete (they be putative 21 century material), applying and progress of this structural system will greatly be promoted.There are some researches prove, the intensity of super high strength high performance concrete is higher, and its fragility will increase, and ductility also can be poor, and under heavily stressed or complex stress condition, super high strength high performance concrete component will control destructive process by fragility, and the reliability of work reduces.But, this novel High Technique Concrete is applied in reinforced concrete composite structure (being called for short SRC structure), i.e. shaped steel super high strength high performance concrete unitized construction (being called for short USUPSRC structure), can maximize favourable factors and minimize unfavourable ones, overcome the weakness of the large and ductility difference of super high strength high performance concrete fragility, its high-performance and economic benefit are given full play to.
In SRC structure, cohesive action good between type Steel concrete is the basis ensureing the medium-sized Steel concrete co-ordination of SRC component, the three kinds of material elements collaborative works of shaped steel, reinforcing bar and concrete, to resist various effects of action, can give full play to its advantage.But one of remarkable difference of SRC structure and reinforced concrete structure is that the cohesive force between type Steel concrete is far smaller than the cohesive force between reinforcing bar and concrete, and the cohesive force of shaped steel and normal concrete is approximately only equivalent to 45% of plain bar cohesive force.Domestic and international many experimental studies show, there is bond-slip phenomenon between type Steel concrete, and have remarkably influenced to the stress performance of SRC component and even supporting capacity.Therefore, how to ensure type Steel concrete effectively collaborative work become one of emphasis of SRC structural research.At present, two kinds are generally had to the treatment process of bond-slip problem between type Steel concrete: the first adds the shearing connecting piece of some amount in component surface by calculating in engineering design, the inconvenience in construction certainly will be caused like this and improve cost, and easily causing the defects such as the congenital microfracture of inside concrete; It two is do not arrange or only arrange a small amount of shearing connecting piece, and in supporting capacity calculates, consider the impact of bond-slip, the supporting capacity of corresponding reduction component, certainly exists uneconomic factor like this.On the other hand, in Structural Design, ubiquity focuses on the phenomenon of intensity and light weather resistance, has occurred the security in use of many concrete structures and the problem of weather resistance aspect both at home and abroad.Namely some concrete structure engineerings completely lose using function and even supporting capacity due to the reason such as alkali-aggregate reaction, Chloride Attack in use half of not enough design period, even there is partial collapse or total Collapse in indivedual engineering, causes casualties or Architectural Equipment destruction.Therefore, in USUPSRC structure, improve the natural adhesive property between shaped steel and super high strength high performance concrete, do not arrange on shaped steel surface or only a small amount of shearing connecting piece is set by detailing requiments and just can ensure that the research of shaped steel and super high strength high performance concrete collaborative work is effectively significant; Meanwhile, the weather resistance of concrete structure engineering also causes close attention and the great attention of people day by day, and becomes problem demanding prompt solution.
Prior art is used for the technology of preparing that the concrete strength grade of reinforced concrete composite structure has the high-strength high-performance concrete of C60, C70, C80, C90 and C100 and the super high strength high performance concrete of C110, C120, C130, C140 and C150, above-mentioned each strength grade concrete significantly improves the adhesive property between shaped steel and (surpassing) high-strength concrete, and improves the weather resistance of structure; But, also there is the super high strength high performance concrete that can not extend to more high strength thus, and the problem of the natural adhesive property difference between shaped steel and super high strength high performance concrete when using it for reinforced concrete composite structure, can not be solved, therefore civil engineering work can not be met extend in aerial, underground and water, namely superelevation is built, super-span, underground, marine or change under water, the requirement of these trend of application and development such as super-durableization and heavy, huge and novel Structural Engineering.In addition, there is part in prior art by the technology of preparing of the strengthening of concrete superelevation, super-durable, but they all do not relate to or the unresolved problem for the natural adhesive property difference between shaped steel during SRC structure and super high strength high performance concrete yet.
Summary of the invention
The object of this invention is to provide a kind of is the super high strength high performance concrete of C160 for reinforced concrete composite structure strength grade.This concrete is applied in reinforced concrete composite structure, can adhesive property under state of nature (that is shaped steel surface does not arrange or only arranges a small amount of shearing connecting piece by detailing requiments) between remarkable modified version Steel concrete, the respective mechanical property of effective performance Steel concrete bi-material and mutual cooperative work performance, thus the significantly supporting capacity of lift structure component and use properties; In addition, this concrete can improve the weather resistance of structure, and has good serviceability, high volume stability and economy.
For solving the problems of the technologies described above, the present invention is achieved in that a kind of concrete for reinforced concrete composite structure C160 strength grade, and this mix proportion is (unit: kg/m
3):
Cement: fine aggregate: coarse aggregate: water: Concrete superplastizer: defoamer: silicon ash: flyash: exciting agent=468: 782: 1116: 108: 16: 1: 65: 117: 6.
The 625R ordinary Portland cement of steady quality, better performances selected by described cement, the compatibility test carried out with poly carboxylic acid series concrete superplasticizer is between the two needed before using, test method adopts the method in existing building material industry standard " cement and water reducer compatibility test method " JC/T1083-2008, and selects the cement type good with poly carboxylic acid series concrete superplasticizer consistency.Selected cement performance index (comprises fineness, SO
3content, content of MgO, presetting period, final setting time, 3 days intensity, 28 days intensity) requirement of national existing relevant criterion should be not less than, and select the cement type that alkali content is few, hydration heat is low, water requiremen is also low.
Described fine aggregate adopts that particle is round and smooth, quality is hard, grating good in partially thick river sand, the quality of sand should be not less than the high-quality sand standard specified in existing building material industry standard " regular concrete sand, stone quality and test method standard " JC/T52-2006 and national standard " building sand " GB/T14684-2001.Its fineness modulus is between 2.8 ~ 3.2, and silt content and clod content all should be not more than 0.5%(by quality ratio), chloride ion content should be not more than 0.05%(in the mass ratio of dry sand).
Described coarse aggregate adopts the artificial rubble being main component with grouan, basalt that quality densification is hard, intensity is high, surface irregularity, particle shape are almost spherical, elongated particles is little, grating is good, and the quality of rubble should be not less than the specified requirement of the relevant criterion such as existing building material industry standard " regular concrete sand, stone quality and test method standard " JC/T52-2006.The cubic compressive strength of its parent rock of coarse aggregate should lower than 140MP.Maximum particle diameter should control at 10mm, and its silt content should be not more than 0.2%(by quality ratio), clod content should be not more than 0.1%(by quality ratio), pin, platy shaped particle content should be not more than 0.5%(by quality ratio), and weathering particle must not be mixed into.When carrying out this Concrete, continuous size fraction rubble Φ 5 ~ Φ 10 is adopted to feed intake.
Through a large amount of tentative simultaneous test and with cement compatibility test, high efficiency water reducing agent selected by this invention is poly carboxylic acid series concrete superplasticizer, its quality should be not less than the specified requirement of the relevant criterion such as existing national standards " concrete admixture " GB8076-2008, and the water-reducing rate of selected high efficiency water reducing agent should be greater than 30%.The maximum saturation volume of selected high efficiency water reducing agent should be not less than 2.5% of whole binder total amount, adopts with mixing method, and needs to carry out compatibility test with selected cement type before using.
AGITANP803 powder defoamer selected by described defoamer.
Described silicon ash should adopt ultra-fine silicon ash, its quality should be not less than the specified requirement of the relevant criterion such as national standard " mineral admixture for high-strength high-performance concrete " GB/T18736-2002, and the dioxide-containing silica in silicon ash should be not less than 95%, water ratio should be not more than 2%, loss on ignition should be not more than 4%, chloride ion content should be not more than 0.01%, and pozzolanic activity index should be greater than 90%, and specific surface area should be not less than 25000m
2/ kg.
High-quality I grade of special fine powdered coal that described flyash adopts the power plant of coal burning process advanced person to produce.Its quality should be not less than the specified requirement of the relevant criterion such as national standard " flyash in cement and concrete " GB/T1596-2005, and its loss on ignition should be not more than 3%, SO
3content should be not more than 2%, and water content should be not more than 1%, and water demand ratio should be not more than 95%, and specific surface area should be greater than 700m
2/ kg, and its fineness (0.045mm square hole sieve tails over, %) should be not more than 10%.
Described exciting agent is by contriver place research team independent development, is through recognizing on the basis that its activity needs to excite further and utilize, by the Starso (Na of 55 ~ 60% to the research of super fine powder coal ash hydration reaction feature
2siO
29H
2o), the white lime (Ca (OH) of 38 ~ 43%
2) and 1.5 ~ 2.5% manganous sulfate (MnSO
4h
2o) formulated by mass percentage a kind of chemical activator.This exciting agent is with early strong ordinary Portland cement, poly carboxylic acid series concrete superplasticizer have good consistency.
Described mixing water selects tap water, and its quality should be not less than the specified requirement of the relevant criterion such as nation-building ministerial standard " the reinforcement of concrete water quality standard " JGJ63-2006, and requires that the alkali content of selected tap water is not more than 1000mg/L.
The present invention gives the concrete preparation method for reinforced concrete composite structure C160 strength grade, and the method adopts the cement improved to wrap up in sandstone method concrete stirring technology, and concrete technology step is as follows:
1) first by Concrete superplastizer 16kg/m
3with exciting agent 6kg/m
3evenly admix load weighted water 108kg/m
3in, obtain mixture;
2) then in forced mixer, 782kg/m is added according to weight proportion
3fine aggregate and step 1) amount of the mixture 1/3, uniform stirring 1 ~ 2min;
3) 1116kg/m is added again
3Φ 5 ~ Φ 10 continuous size fraction rubble coarse aggregate and step 1) amount of the mixture 1/3, uniform stirring 2 ~ 4min;
4) whole consolidating material is then added: 468kg/m
3cement, 65kg/m
3silicon ash and 117kg/m
3flyash, uniform stirring 2 ~ 3min;
5) finally 1kg/m is added
3defoamer and remaining step 1) mixture, uniform stirring 2 ~ 3min, stop and to stir 2 ~ 3min after 3 minutes again to evenly, discharging, obtains the concrete mix of C160 strength grade.
The invention has the beneficial effects as follows:
1. the concrete that the present invention produces a kind ofly is applicable to the super high strength high performance concrete that reinforced concrete composite structure strength grade is C160.This concrete is in mechanical property (the i.e. C160 intensity guaranteeing that it should possess, the indexs such as plasticity) and there is high-durability, high workability, on the basis of high volume stability and economy, improve the natural adhesive property between this concrete and shaped steel significantly, make it be applied in steel reinforced concrete structure design and add shearing connecting piece without the need to (or only needing by detailing requiments a little) on shaped steel surface, shaped steel and this concrete effective collaborative work can be ensured, thus decrease working procedure, steel are saved, improve operating efficiency, and avoid and on shaped steel surface, shearing connecting piece be set in a large number and easily cause the defects such as the congenital microfracture of this inside concrete, there is significant economic benefit and construction quality improvement effect, its mechanical property comparative test result is in table 2.
2. poly carboxylic acid series concrete superplasticizer (water-reducing rate should be greater than 30%) selected by the high efficiency water reducing agent used in the present invention, compares the water reducer of other type, and with early the consistency of ordinary Portland cement is good by force, it is not containing Na
2sO
4, can further improve this concrete weather resistance.
3. powder defoamer selected by the defoamer used in the present invention, model is AGITANP803, can in concrete-agitating process formed and a large amount of microvesicles still remained in after vibration compacting in concrete carry out deaeration, its degree of compactness is effectively improved, enhances concrete weather resistance and shear stability.
4. the alkali-activator (XJFAA) of independent development selected by the exciting agent used in the present invention, the concrete being mixed with flyash can be made to have certain micro-expansibility, improve concrete shrinkage; Can strengthen in flyash hydro-combination process with the Vitrea corrosive nature of three-D space structure that aluminosilicate is main aquation component, excite the lateral reactivity of flyash, improve the power of forward hydration reaction, generate the crystal such as more C-S-H gel, drated calcium aluminate and hydrated calcium silicate, the intensity of institute's concrete batching and corrosion resistance are increased significantly.
5. what the present invention produced is C160 for reinforced concrete composite structure strength grade, and super high strength high performance concrete is under normal concrete manufacturing condition, and the employing cement that minimizing cement granules and superfine active mineral grain fly upward everywhere when concrete-agitating wraps up in the feeding method realization of sandstone stirring technique as far as possible, preparation technology is simple and be easy to realize, be suitable for through engineering approaches and industrialization, be convenient to large-scale promotion application, there is good social benefit.
6. what the present invention produced is containing a large amount of flyash, silicon ash in the starting material of the super high strength high performance concrete of C160 for reinforced concrete composite structure strength grade; they are industrial waste and waste; it is dissolved and can make tremendous contribution to environment protection; meet the requirement of Sustainable development; a kind of green concrete, a kind of environment-friendly material.
7. the starting material (comprising industrial waste) that the present invention selects are mass-produced market circulation, buy and sell product, and starting material are easy to get.
8. what the present invention produced is C160 for reinforced concrete composite structure strength grade, and super high strength high performance concrete is disastrously expected (superfined flyash and Ultrafine Grinding silica flour) by adding superfine active mineral, utilize the pozzolanic reaction of active mineral admixture, reinforcing effect, filling effect, weather resistance improves the warm peak subtractive effect of effect and super high strength high performance concrete hydration heat, and make full use of the over-superimposed effect that active mineral admixture compound is mixed and the composite blend of active mineral admixture and high efficiency water reducing agent produces, according to them and cement granules, coarse-fine aggregate particle diameter does not optimize the grain composition of gelling material part in super high strength high performance concrete material in the feature of same one-level, not only make to gather materials in super high strength high performance concrete and the pore structure of interface structure between Behavior of Hardened Cement Paste and Behavior of Hardened Cement Paste all obtains and significantly improves, improve the density of Behavior of Hardened Cement Paste, impervious, typical dense structure can expand to aggregate surface simultaneously, thus make super high strength high performance concrete more closely knit hard, the mechanical property (adhesive property especially and between shaped steel) of super high strength high performance concrete, endurance quality and serviceability all improve a lot.
Embodiment
The present invention be with modified version Steel concrete remarkable under state of nature (that is shaped steel surface does not arrange or only arranges a small amount of shearing connecting piece by detailing requiments) between adhesive property, the respective mechanics of effective performance Steel concrete bi-material and cooperative work performance, thus the significantly supporting capacity of lift structure component and performance, and the weather resistance improving structure is aim, study for reinforced concrete composite structure strength grade the technology of preparing of the super high strength high performance concrete being C160.At present, the quality of the ordinary Portland cement that domestic and international making super high strength high performance concrete is used and strength increases high, processing technology and the quality of active mineral admixture used (silicon ash, flyash etc.) are updated, in addition the research and apply of the concrete admixture such as superplasticizer has achieved larger progress all, and defoamer and the exciting agent research and apply in concrete also just progressively develops, thus identify basis for the realization of above-mentioned study tenet.Meanwhile, the cement consumption of the requirement of super high strength high performance concrete is relatively less, and produces a large amount of discharges that cement means carbonic acid gas, therefore alleviates the Greenhouse effect caused the earth to a certain extent; It requires sufficient amount and accounts for the active mineral additives of the high-quality such as the larger flyash of consolidating material proportion, silicon ash; mean the reasonable treatment and use of industrial waste; form good production cycle and environment protection by being conducive to, and the active mineral additives of these high-qualitys improves required for concrete material self performance just.In a word, application super high strength high performance concrete can be saved cement, turned waste into wealth by industrial waste, extending structure engineering working life, and finally preserves the ecological environment and natural resources.In sum, for the research and development of the super high strength high performance concrete of reinforced concrete composite structure by for using concrete to walk out the road of a Sustainable development better, it is by the integration capability of lift structure engineering and performance, promote that steel-concrete combined structure is in China, especially the high level in highlight lines and frequently occurred earthquake area, high-rise building, offshore platform or underwater structure, hypogee, greatly across, apply in heavy type structure, improve the scientific and technological content of building structure in Infrastructure and human settlement, and play it there is larger supporting capacity and rigidity, good anti-seismic performance, construction speed is fast, good and the unique advantage such as Social and economic benef@significantly of durable and resistivity against fire.Therefore, shaped steel super high strength high performance concrete unitized construction has very high engineer applied value and wide market outlook.
What the present invention developed is the super high strength high performance concrete of C160 for reinforced concrete composite structure strength grade, except adopting similar material-cement, sand, rubble, water with normal concrete, also add its indispensable component: Concrete superplastizer and active mineral admixture (silicon ash, flyash), be also mixed with powder defoamer and exciting agent in addition.Super high strength high performance concrete is different from normal concrete, and its intensity and performance are all more common to be greatly improved with high-strength concrete.The water cement ratio of super high strength high performance concrete is generally all less than 0.24, and the water cement ratio of common and high-strength concrete is generally more than 0.30, and the maximum size of coarse aggregate of super high strength high performance concrete is also less than common and high-strength concrete.Above-mentioned every difference result in super high strength high performance concrete and common and high-strength concrete has very large difference in performance, disastrously expect by adding superfine active mineral, utilize the pozzolanic reaction of superfine active mineral spike, filling effect and plasticization effect, optimize the grain composition of gelling material part in super high strength high performance concrete material, not only make to gather materials in super high strength high performance concrete and the pore structure of interface structure between Behavior of Hardened Cement Paste and Behavior of Hardened Cement Paste all obtains and significantly improves, improve the density of Behavior of Hardened Cement Paste, impervious, typical dense structure can expand to aggregate surface simultaneously, thus make super high strength high performance concrete more closely knit hard, the mechanical property (adhesive property especially and between shaped steel) of super high strength high performance concrete and endurance quality all improve a lot.Simultaneously, by mixing of powder defoamer, can reduce and to be formed in concrete-agitating process and a large amount of bubbles still remaining in the transition zone, interface in concrete in cement slurry or between cement slurry and aggregate after vibration compacting carry out deaeration, its degree of compactness is effectively improved, no small contribution has all been made to the mechanical property (comprising the adhesive property between shaped steel) of super high strength high performance concrete and the raising of endurance quality.In addition, by the admixture of exciting agent, concrete can be made to have certain micro-expansibility, improve concrete shrinkage; Can strengthen in flyash hydro-combination process with the Vitrea corrosive nature that aluminosilicate is main aquation component, increase the activity of flyash, improve the power of forward hydration reaction, generate the crystal such as more C-S-H gel, drated calcium aluminate and hydrated calcium silicate, the intensity of institute's concrete batching and corrosion resistance are increased significantly.
With Binder Phase between plain bar and concrete seemingly, the cohesive force between type Steel concrete also forms primarily of chemical bond power, friction resistance and mechanical snap power three part.Each integral part of cohesive force between type Steel concrete is all closely related with concrete performance.
Chemical bond power is the chemical clinging power that produces on shaped steel surface of cement gel body in concrete or adsorptive power, and its (shearing resistance) ultimate value depends on the character of cement and the degree of roughness on shaped steel surface.During casting concrete, cement slurry produces surface tension at steel surface, and under capillary effect, the cement slurry on steel surface will form self-equilibrating; Deposit concrete generally will vibrate, and power of vibrating (disturbance) can be strengthened and accelerate the infiltration of cement slurry to steel surface zone of oxidation; Cement slurry crystallization in maintenance processes, cement crystal forms chemical bond power.Chemical bond power only exists under the original formation state of Steel Reinforced Concrete Members, once there is (locally) bond-slip on joint face, cement crystal will be cut off and attrition crushing, and chemical bond power is then lost.The principal element affecting chemical bond power has concrete strength, shaped steel steel surface degree of roughness, test specimen to build mode and the maintenance in vibrate degree and later stage and concrete contraction situation etc.
After chemical bond power is lost, due to the steel surface changed condition (steel surface is uneven) caused by the coarse injustice of steel surface and other reason, concrete crystal grain on itself and contact surface is interlocked, material is thus formed mechanical snap power.For plant produced and the shaped steel such as rolled steel joist of process postmenstruation, once bond-slip development is accelerated, the crushed integration of concrete crystal on shaped steel and concrete surface, at this moment mechanical snap power also substantial loss.The principal element affecting mechanical snap power is the degree of roughness of shaped steel steel surface and the force way etc. of surface appearance (corrosion degree etc.), aggregate grating, concrete strength and Steel Reinforced Concrete Members.
Shaped steel surrounding concrete is also formed after the bond failure between type Steel concrete to the friction resistance of shaped steel, and mainly just plays a role after mechanical snap power is lost substantially.When chemical bond power; especially after mechanical snap power is lost; owing to being cut off with the concrete crystal on shaped steel contact surface, crush and expand; in addition the lateral confinement such as protective layer and stirrup; positive pressure will be produced on shaped steel and concrete joint face; add that on joint face, frictional coefficient is comparatively large, thus define friction resistance.Friction resistance all exists after chemical bond power is lost always, is the major portion of later stage cohesive force between type Steel concrete.Affect friction resistance because have the size of adhesive surface between the shaped-steel layout of shaped steel and surface characteristic thereof, type Steel concrete, member stress mode, aggregate grating and affecting the factor (thickness of concrete cover of shaped steel, stirrup ratio, concrete shrinkage) etc. of lateral confinement.
Key technical problem to be solved by this invention is, guaranteeing mechanical property (i.e. intensity and plasticity) that super high strength high performance concrete should possess and there is high-durability, high workability, on the basis of high volume stability and economy, improve (nature) adhesive property between concrete and shaped steel significantly, make to add shearing connecting piece without the need to (or only needing by detailing requiments a little) on shaped steel surface in steel reinforced concrete structure design, can ensure to have between type Steel concrete bonding and anchoring reliably, make both energy under loading action harmonious, cooperation.
The present invention from theory and design in principle, break the restriction of " full sieve rice " formula, by orthogonal experiment and contrast experiment's method, consider Concrete superplastizer, defoamer, between exciting agent three and with the consistency of cement, maximum size of coarse aggregate, between coarse aggregate different-grain diameter and and fine aggregate particle diameter between level match the performance factor such as the impact of concrete strength and performance and the pozzolanic activity of active mineral additives, select high-quality coarse-fine aggregate and control particle diameter and grating, appropriate Concrete superplastizer and high-quality active mineral ultrafine powder is mixed in super high strength high performance concrete its preparing materials, and consider adding of defoamer and exciting agent, reduce water cement ratio, based on the existing material that is easy to get in locality, do not change conventional production process, fly upward for reducing cement granules and superfine active mineral grain when concrete-agitating the feeding method adopting cement to wrap up in sandstone stirring technique everywhere as far as possible, utilize the pozzolanic reaction of active mineral admixture, reinforcing effect, filling effect, weather resistance improves the warm peak subtractive effect of effect and super high strength high performance concrete hydration heat, and make full use of the over-superimposed effect and the deaeration effect of defoamer and the activity excitation effect of exciting agent that active mineral admixture compound is mixed and the composite blend of active mineral admixture and high efficiency water reducing agent produces, make mechanical property (adhesive property especially and between shaped steel) good, serviceability is excellent, excellent in durability, the strength grade being applicable to reliability application in steel reinforced concrete structure of advantage of lower cost is the super high strength high performance concrete of C160.Mechanical property test comparing result of the present invention is as shown in table 2.
When the present invention selects starting material, not only require that starting material are high-quality, the starting material also requiring preparation super high strength high performance concrete used are that locality is easy to get.In addition, consider that the intensity of institute's concrete batching is very high, according to maximum density theory, the grain composition of coarse-fine aggregate in concrete material is optimized, makes large or fine granule have mutually good filling, to reduce the voidage of aggregate; Simultaneously, the median size of general cement is 20 ~ 30 μm, the particle being less than 10 μm is also few, and the grain diameter of active mineral admixture is tiny more than cement granules particle diameter, the median size of superfined flyash is 3 ~ 6 μm, space between energy filling concrete particle, the median size of silicon ash is less, it is 0.10 ~ 0.26 μm, space between energy filling concrete particle and superfined flyash particle and between superfined flyash particle, so be optimized also most important in prepared super high strength high performance concrete material to the grain composition of gelling material part.And the outside deteriorated factor (as factors such as vitriol) depends on concrete pore structure to a great extent to concrete aggressiveness, and this causes the major cause of Durability of Concrete just.Mixing of active mineral admixture, reduce the voidage with interface between cement granules, make water mudrock structure and interface structure more fine and close, block the permeation pathways that may be formed, thus the impermeability of prepared super high strength high performance concrete is increased substantially, water and other various etching medium (CL
--, SO4
2-, CO2 etc.) be all difficult to enter inside concrete, and can reduce the occurrence probability of Alkali-silica reaction and the generation probability of Losantin, its intensity and endurance quality are greatly improved.Namely when the macropore content being greater than 0.1 μm in water mudrock structure and interface structure is lower, the improvement of the properties of prepared super high strength high performance concrete will be conducive to, otherwise, all unfavorable to the intensity of prepared super high strength high performance concrete, anti-permeability performance, corrosion resistance and endurance quality.
After replacing part of cement with active mineral admixture, the mineral admixture that the portion of water in cement granules space can also be made to be filled in it cements out, and the degree of mobilization of cement paste can be made to increase.But also not all mineral admixture all has this significant plasticization effect, mainly because the specific surface area of amount of activated mineral admixture is too large or itself have vesicular structure, although it can displace the portion of water in cement paste after replacing cement, but because itself water suction or wetted surface need more free water, cause the mobility of cement paste not increase.In order to ensure the high workload performance of developed super high strength high performance concrete, the method that the present invention adopts Concrete superplastizer and active mineral admixture compound to mix, under both collaborative works, the subparticle of active mineral additives has not only given full play to their filling effect, and the moisture be filled among space is cemented out, between making between particle, water-resisting layer thickeies; In addition, the subparticle of active mineral admixture has adsorbed Concrete superplastizer molecule, the electrostatic repulsion that the electrostatic double layer current potential that its surface is formed produces is greater than the universal gravitation between powder particle, powder granule is impelled to disperse, and aggravate the dispersion of cement granules further, the mobility of cement paste is increased, thus effectively improves the mobility of compound; Meanwhile, the compound of super fine active mineral admixture is mixed and is reduced hydration heat, can improve concrete volume stability.
Higher inherent strength, toughness and stability should be had for the aggregate prepared in the starting material of super high strength high performance concrete, so that various Static and dynamic stress, impact and abrasive action can be resisted, and the decline of institute's concrete batching performance can not be caused.Because the condition of surface of different aggregate is different, cause the cohesive strength between cement slurry with aggregate also not identical, rubble has higher cohesive strength compared with cobble under normal circumstances; On the other hand, in cement slurry, silicon ash content ratio asynchronous cohesive strength difference is also very large, and when mixing silicon ash, the cohesive strength between cement slurry and aggregate is than much higher when not mixing.Normal concrete is when destroying, the bonding interface of cement slurry and aggregate is weak link, crack occurs along the interface of cement slurry and aggregate, aggregate generally can not destroy, and extraneous corrode also often from then on interface start development, and the bonding interface of cement slurry in super high strength high performance concrete and aggregate is no longer weak link, its destruction also no longer occurs along interface, but cause due to the destruction of aggregate, therefore the performance of performance on super high strength high performance concrete of aggregate has larger impact.The fine aggregate selected in research of the present invention adopts that particle is round and smooth, quality is hard, grating is good, silt content little in thick river sand; The artificial rubble being main component with grouan, basalt that coarse aggregate is surface irregularity, fine quality, grating is good, its maximum particle diameter should control at 10mm.Like this, concrete homogeneity has been got back further lifting, thus makes concrete more closely knit, and intensity also can be further enhanced.
The present invention adopts cement to wrap up in sandstone method (the SEC method also known as improving) concrete stirring technology in the preparation, stir in forced mixer, its feeding sequence is: first poly carboxylic acid series concrete superplasticizer and exciting agent are evenly admixed in load weighted water, obtain mixture; Then add fine aggregate and be mixed with 1/3 → stir (1 ~ 2 minute) of superplasticizer and exciting agent amount of the mixture → add coarse aggregate and be mixed with whole consolidating material (cement, silicon ash and flyash) → stir (2 ~ 3 minutes), 1/3 → stir (2 ~ 4 minutes) of superplasticizer and exciting agent amount of the mixture → add → add defoamer and residue is mixed with superplasticizer and exciting agent mixture → uniform stirring (2 ~ 3 minutes) → stops is stirred to even (2 ~ 3 minutes) → discharging again after 3 minutes.This technique can reduce cement granules as far as possible and superfine active mineral grain flies upward everywhere when concrete-agitating, and can improve prepared concrete intensity, and prepared concrete should not occur segregation phenomenon, and bleeding is few, and serviceability is relatively better.
Embodiment:
(1) starting material
1. cement
Select the Qinling Mountains board PO62.5R cement of steady quality, better performances, carry out compatibility test between the two with poly carboxylic acid series concrete superplasticizer before using, test method adopts the method in existing building material industry standard " cement and water reducer compatibility test method " JC/T1083-2008, good with poly carboxylic acid series concrete superplasticizer consistency.Selected cement performance index meets the requirement of national existing relevant criterion, and its alkali content is few, hydration heat is low, water requiremen is also low.
2. aggregate
Fine aggregate adopts that particle is round and smooth, quality is hard, grating good in partially thick, Ba river sand, the quality of sand meets the high-quality sand standard specified in existing building material industry standard " regular concrete sand, stone quality and test method standard " JC/T52-2006 and national standard " building sand " GB/T14684-2001.Its fineness modulus is 3.0, and silt content and clod content all control at 0.5%(in mass) below, chloride ion content controls at 0.05%(in the quality of dry sand) below.
Coarse aggregate adopts quality densification hard, and intensity is high, surface irregularity, and particle shape is almost spherical, and pin, sheet content are little, the artificial rubble that grating is good, and its main component grouan and basalt content (in mass) are not less than 90%.The quality of rubble meets the specified requirement of the relevant criterion such as existing building material industry standard " regular concrete sand, stone quality and test method standard " JC/T52-2006.The cubic compressive strength of aggregate parent rock is 150 ~ 250MPa.Maximum particle diameter controls at 10mm, and silt content controls at 0.2%(in mass) below, clod content controls at 0.1%(in mass) below, pin, platy shaped particle content control at 0.5%(in mass) below, and weathering particle must not be mixed into.When carrying out this Concrete, continuous size fraction rubble Φ 5 ~ Φ 10 is adopted to feed intake.
3. flyash
Adopt high-quality I grade of special fine powdered coal that the power plant of coal burning process advanced person produces.Its quality meets the specified requirement of the relevant criterion such as national standard " flyash in cement and concrete " GB/T1596-2005, and its fineness (0.045mm square hole sieve tails over, %) is not more than 5%, and loss on ignition is 2.2%, SO
3content is 1.5%, and water demand ratio is less than 95%, and specific surface area is about 1000m
2/ kg.
4. silicon ash
The quality of the ultra-fine silicon ash selected meets the specified requirement of the relevant criterion such as national standard " mineral admixture for high-strength high-performance concrete " GB/T18736-2002, dioxide-containing silica in silicon ash is not less than 99%, water ratio is 1.5%, chloride ion content is not more than 0.01%, loss on ignition is 2.7%, pozzolanic activity index is 95%, and specific surface area is about 30000m
2/ kg.
5. Concrete superplastizer
Through a large amount of tentative simultaneous test and with cement compatibility test, high efficiency water reducing agent selected by this invention is poly carboxylic acid series concrete superplasticizer, its quality should be not less than the specified requirement of the relevant criterion such as existing national standards " concrete admixture " GB8076-2008, and the water-reducing rate of selected high efficiency water reducing agent should be greater than 30%.The maximum saturation volume of selected high efficiency water reducing agent is not less than 2.5% of whole binder total amount, adopts with mixing method, and needs to carry out compatibility test with selected cement type before using.
6. exciting agent
Select by contriver place research team according to super fine powder coal ash hydration reaction feature and the flyash lateral reactivity exciting agent (XJFAA) exciting and utilize its active independent development further, by the Starso (Na of 55 ~ 60%
2siO
39H
2o), the white lime (Ca (OH) of 38 ~ 43%
2) and 1.5 ~ 2.5% manganous sulfate (Na
2siO
39H
2o) formulated by mass percentage a kind of chemical activator, refers to table 1.This exciting agent is with early strong ordinary Portland cement, poly carboxylic acid series concrete superplasticizer have good consistency.
The different ratio of table 1XJFAA exciting agent
7. mixing water
Select tap water to be mixing water, its quality meets the specified requirement of the relevant criterion such as Minstry of Housing and Urban-Rural Development of People Republic of China's ministerial standard " concrete mixing water supply standard " JGJ63-2006, and alkali content is less than 800mg/L.
(2) proportioning
The proportioning that the super high strength high performance concrete that the present invention is C160 for the strength grade will applied in steel reinforced concrete structure provides is as shown in table 2.
Table 2 is for the super high strength high performance concrete proportioning (unit: kg/m of reinforced concrete composite structure
3)
(3) stirring technique
This invention adopts cement to wrap up in sandstone method concrete stirring technology, and concrete technology step is as follows:
First by poly carboxylic acid series concrete superplasticizer 16kg/m
3with exciting agent 6kg/m
3evenly admix load weighted water 108kg/m
3in, obtain mixture; Then, in forced mixer, 782kg/m is added according to weight proportion
3fine aggregate and be mixed with 1/3 of superplasticizer and exciting agent amount of the mixture, uniform stirring is after 1 ~ 2 minute; Add 1116kg/m again
3coarse aggregate (Φ 5 ~ Φ 10 continuous size fraction rubble) and be mixed with 1/3 of superplasticizer and exciting agent amount of the mixture, uniform stirring is after 2 ~ 4 minutes; Then whole consolidating material is added: 468kg/m
3cement, 65kg/m
3silicon ash and 117kg/m
3flyash, uniform stirring, after 2 ~ 3 minutes, adds 1kg/m
3aGITANP803 powder defoamer and residue be mixed with the mixture of superplasticizer and exciting agent, uniform stirring 2 ~ 3 minutes, stops after 3 minutes and stir 2 ~ 3 minutes again to even, discharging, obtains the concrete mix of C160 strength grade.
This technique can reduce cement granules as far as possible and superfine active mineral grain flies upward everywhere when concrete-agitating, and can improve prepared concrete intensity, and prepared concrete should not occur segregation phenomenon, and bleeding is few, and serviceability is relatively better.
(4) mechanical property test Comparative result
The strength grade being applicable to reinforced concrete composite structure prepared according to above-mentioned proportioning is that the mechanical property comparative test result of the super high strength high performance concrete of C160 and general super high strength concrete (strength grade is the concrete of C160) is as shown in table 3.
Table 3 mechanical performance of concrete comparative test result
As can be seen from Table 3, the strength grade prepared by this technology is the super high strength high performance concrete of C160, achieve in mechanical property (the i.e. C160 intensity guaranteeing that it should possess, the indexs such as plasticity) and there is high-durability, high reliability, high workability, on the basis of high volume stability and economy, improve (nature) adhesive property between concrete and shaped steel significantly, make to add shearing connecting piece without the need to (or only needing by detailing requiments a little) on shaped steel surface in steel reinforced concrete structure design, shaped steel and concrete effective collaborative work can be ensured, thus decrease working procedure, steel are saved, improve operating efficiency, and avoid and on shaped steel surface, shearing connecting piece be set in a large number and easily cause the defects such as the congenital microfracture of inside concrete, significant economic benefit and construction quality improvement effect can be brought, there is higher engineer applied be worth and wide market outlook.
Claims (2)
1. for a concrete for reinforced concrete composite structure C160 strength grade, it is characterized in that, this concrete is according to kg/m
3proportioning be:
Cement: fine aggregate: coarse aggregate: water: Concrete superplastizer: defoamer: silicon ash: flyash: exciting agent=468: 782: 1116: 108: 16: 1: 65: 117: 6;
Self-control flyash excitant XJFAJ selected by described exciting agent, is prepared from by the raw material of following mass percent:
Starso 55 ~ 60%, white lime 38 ~ 43%, manganous sulfate 1.5 ~ 2.5%;
625R ordinary Portland cement selected by described cement;
Described fine aggregate adopts fineness modulus to be that particle between 2.8 ~ 3.2 is round and smooth, quality is hard, grating good in partially thick river sand; By quality ratio, its silt content and clod content should be not more than 0.5%; In the mass ratio of dry sand, its chloride ion content should be not more than 0.05%;
Described coarse aggregate adopts the artificial rubble being main component with grouan, basalt that quality densification is hard, intensity is high, surface irregularity, particle shape are almost spherical, elongated particles is little, grating is good, feeds intake according to continuous size fraction rubble Φ 5 ~ Φ 10; The cubic compressive strength of its parent rock of coarse aggregate should be not less than 140MP, and maximum particle diameter should control at 10mm; By quality ratio, its silt content should be not more than 0.2%, and clod content should be not more than 0.1%, and pin, platy shaped particle content should be not more than 0.5%, and must not be mixed into weathering particle;
Described Concrete superplastizer selects poly carboxylic acid series concrete superplasticizer, and water-reducing rate should be greater than 30%, and maximum saturation volume should be not less than 2.5% of whole binder total amount;
AGITANP803 powder defoamer selected by described defoamer;
Described silicon ash adopts ultra-fine silicon ash, and the dioxide-containing silica in silicon ash should be not less than 95%, and water ratio should be not more than 2%, loss on ignition should be not more than 4%, chloride ion content should be not more than 0.01%, and pozzolanic activity index should be greater than 90%, and specific surface area should be not less than 25000m
2/ kg;
Described flyash adopts high-quality I grade of special fine powdered coal, and 0.045mm square hole sieve tails over and should be not more than 10%, and its loss on ignition should be not more than 3%, SO
3content should be not more than 2%, and water content should be not more than 1%, and water demand ratio should be not more than 95%, and specific surface area should be greater than 700m
2/ kg.
2. based on the concrete preparation method for reinforced concrete composite structure C160 strength grade according to claim 1, it is characterized in that, the method adopts the cement improved to wrap up in sandstone method concrete stirring technology, and concrete technology step is as follows:
1) first by Concrete superplastizer 16kg/m
3with exciting agent 6kg/m
3evenly admix load weighted water 108kg/m
3in, obtain mixture;
2) then in forced mixer, 782kg/m is added according to weight proportion
3fine aggregate and step 1) amount of the mixture 1/3, uniform stirring 1 ~ 2min;
3) 1116kg/m is added again
3Φ 5 ~ Φ 10 continuous size fraction rubble coarse aggregate and step 1) amount of the mixture 1/3, uniform stirring 2 ~ 4min;
4) whole consolidating material is then added: 468kg/m
3cement, 65kg/m
3silicon ash and 117kg/m
3flyash, uniform stirring 2 ~ 3min;
5) finally 1kg/m is added
3defoamer and remaining step 1) mixture, uniform stirring 2 ~ 3min, stop and to stir 2 ~ 3min after 3 minutes again to evenly, discharging, obtains the concrete mix of C160 strength grade.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310491758.5A CN103539407B (en) | 2013-10-18 | 2013-10-18 | Concrete for steel reinforced concrete combined structure with C160 strength level |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310491758.5A CN103539407B (en) | 2013-10-18 | 2013-10-18 | Concrete for steel reinforced concrete combined structure with C160 strength level |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103539407A CN103539407A (en) | 2014-01-29 |
| CN103539407B true CN103539407B (en) | 2015-06-10 |
Family
ID=49963323
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310491758.5A Expired - Fee Related CN103539407B (en) | 2013-10-18 | 2013-10-18 | Concrete for steel reinforced concrete combined structure with C160 strength level |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103539407B (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104860613B (en) * | 2015-06-10 | 2017-02-01 | 上海建工材料工程有限公司 | 160MPa super-strength concrete with high cracking resistance and high fluidity |
| CN105481318B (en) * | 2015-12-25 | 2018-02-27 | 西安建筑科技大学 | A kind of concrete for reinforced concrete composite structure C40 strength grades |
| CN105601202B (en) * | 2015-12-25 | 2018-02-27 | 西安建筑科技大学 | A kind of concrete for reinforced concrete composite structure C55 strength grades |
| CN105439517B (en) * | 2015-12-25 | 2018-02-27 | 西安建筑科技大学 | A kind of concrete for reinforced concrete composite structure C45 strength grades |
| CN105601200B (en) * | 2015-12-25 | 2018-02-27 | 西安建筑科技大学 | A kind of concrete for reinforced concrete composite structure C35 strength grades |
| CN105621995B (en) * | 2015-12-25 | 2018-02-27 | 西安建筑科技大学 | A kind of concrete for reinforced concrete composite structure C30 strength grades |
| CN105837119B (en) * | 2016-04-08 | 2017-09-19 | 西安建筑科技大学 | A kind of concrete for reinforced concrete composite structure C230 strength grades |
| CN105777017B (en) * | 2016-04-08 | 2017-10-24 | 西安建筑科技大学 | A kind of concrete for reinforced concrete composite structure C250 strength grades |
| CN105859216B (en) * | 2016-04-08 | 2017-11-10 | 西安建筑科技大学 | A kind of concrete for reinforced concrete composite structure C220 strength grades |
| CN105693170B (en) * | 2016-04-08 | 2017-09-19 | 西安建筑科技大学 | A kind of concrete for reinforced concrete composite structure C210 strength grades |
| CN105906258B (en) * | 2016-04-08 | 2017-09-19 | 西安建筑科技大学 | A kind of concrete for reinforced concrete composite structure C240 strength grades |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101913815A (en) * | 2010-08-18 | 2010-12-15 | 西安建筑科技大学 | Concrete with strength grade of C140 used for profile steel-concrete composite structure |
| CN101913822A (en) * | 2010-08-18 | 2010-12-15 | 西安建筑科技大学 | C150 (strength grade) concrete for section steel-concrete combined structure |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2653402B2 (en) * | 1987-05-22 | 1997-09-17 | 電気化学工業株式会社 | Ultra high strength cement composition |
| JPH0753595B2 (en) * | 1987-06-02 | 1995-06-07 | 東京電力株式会社 | Manufacturing method of concrete etc. |
-
2013
- 2013-10-18 CN CN201310491758.5A patent/CN103539407B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101913815A (en) * | 2010-08-18 | 2010-12-15 | 西安建筑科技大学 | Concrete with strength grade of C140 used for profile steel-concrete composite structure |
| CN101913822A (en) * | 2010-08-18 | 2010-12-15 | 西安建筑科技大学 | C150 (strength grade) concrete for section steel-concrete combined structure |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103539407A (en) | 2014-01-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103539407B (en) | Concrete for steel reinforced concrete combined structure with C160 strength level | |
| CN103553458B (en) | C180 strength-grade concrete for formed steel concrete composite structure | |
| CN103553459B (en) | C190 strength-grade concrete for formed steel concrete composite structure | |
| CN103553460B (en) | C200 strength-grade concrete for formed steel concrete composite structure | |
| CN101913815B (en) | Concrete with strength grade of C140 used for profile steel-concrete composite structure | |
| CN103553494B (en) | C170 strength-grade concrete for formed steel concrete composite structure | |
| CN101913822B (en) | C150 (strength grade) concrete for section steel-concrete combined structure | |
| CN101250040B (en) | Concrete with strength grade of C100 used for steel reinforced concrete combined structure | |
| CN105837119B (en) | A kind of concrete for reinforced concrete composite structure C230 strength grades | |
| CN105481317B (en) | A kind of concrete for reinforced concrete composite structure C50 strength grades | |
| CN101913816B (en) | C130 (strength grade) concrete for section steel-concrete combined structure | |
| CN105439517B (en) | A kind of concrete for reinforced concrete composite structure C45 strength grades | |
| CN105621995B (en) | A kind of concrete for reinforced concrete composite structure C30 strength grades | |
| CN105777017B (en) | A kind of concrete for reinforced concrete composite structure C250 strength grades | |
| CN101195530B (en) | Concrete with strength grade of C70 for section steel concrete composite structure | |
| CN105693170B (en) | A kind of concrete for reinforced concrete composite structure C210 strength grades | |
| CN105906258B (en) | A kind of concrete for reinforced concrete composite structure C240 strength grades | |
| CN105601202B (en) | A kind of concrete for reinforced concrete composite structure C55 strength grades | |
| CN105859216B (en) | A kind of concrete for reinforced concrete composite structure C220 strength grades | |
| CN101921092B (en) | Concrete for profiled steel concrete composite structure with C110 in strength grade | |
| CN100577598C (en) | Concrete with strength grade of C90 for section steel concrete composite structure | |
| CN101913823B (en) | Concrete with strength grade of C120 for section steel concrete combination structure | |
| CN105481318B (en) | A kind of concrete for reinforced concrete composite structure C40 strength grades | |
| CN105601200B (en) | A kind of concrete for reinforced concrete composite structure C35 strength grades | |
| CN101195532B (en) | Concrete with strength grade of C80 for section steel concrete composite structure |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20150610 Termination date: 20181018 |