CN105601200B

CN105601200B - A kind of concrete for reinforced concrete composite structure C35 strength grades

Info

Publication number: CN105601200B
Application number: CN201510991591.8A
Authority: CN
Inventors: 郑山锁; 董方园; 郑捷; 王斌; 李磊; 王帆; 侯丕吉; 周炎; 张晓辉
Original assignee: Xian University of Architecture and Technology
Current assignee: Xian University of Architecture and Technology
Priority date: 2015-12-25
Filing date: 2015-12-25
Publication date: 2018-02-27
Anticipated expiration: 2035-12-25
Also published as: CN105601200A

Abstract

The invention discloses a kind of concrete for reinforced concrete composite structure C35 strength grades, match ratio is：Cement: fine aggregate: coarse aggregate: water: high efficiency water reducing agent: defoamer：Silicon ash: flyash：Composite exciting agent (kg/m³)=290: 735: 1103: 150: 4: 1: 20: 70: 2.Its preparation method is：First polycarboxylic acid series high efficiency water reducing agent and composite exciting agent are uniformly admixed in load weighted water and obtain mixture, the 1/3 of fine aggregate and amount of the mixture is sequentially added in mixer according to weight proportion, stirring, the 1/3 of coarse aggregate and amount of the mixture is added, stirring, adds cement, silicon ash and flyash, stirring, defoamer and remaining mixture are added, is stirred, discharging.The concrete can significantly improve the adhesive property between shaped steel and concrete in its natural state, effectively play steel and two kinds of respective mechanical properties of material of concrete and mutual cooperative work performance, so as to the bearing capacity and performance of significantly lift structure component, the durability of structure is improved.

Description

A kind of concrete for reinforced concrete composite structure C35 strength grades

Technical field

The invention belongs to building material technical field, and be related to one kind is for reinforced concrete composite structure strength grade C35 high performance concretes.

Background technology

The invention of Portland cement in 1824 makes concrete technology obtain rapid development, and its dosage is big, is applicable model That encloses may extensively occupy the first in the world.Although concrete is a kind of traditional manufactured construction materials, because it is excellent with not replacing More property (abundant raw material, simple production process, it is cost-effective the advantages that) and concrete material science and technology continuous progress, Concrete has turned into the main body of civil engineering material, also will be indispensable master in the civil engineering in future and nation-building One of material.Meanwhile as the continuous expansion of city size, population are on the increase, the continuous rise of land price, build local environment Harshization, the continuous progress and rapid development of economy of Building technology, building increasingly prolongs into aerial, underground and water Stretch, that is, build (super) heightization, (super) greatly across the development of change, underground, lightweight and heavy type structure, especially steel reinforced concrete knot Structure superelevation, super-span, underground, sea or underwaterization, lightweight etc. be novel or the application of megaplex engineering field, Requirement to this construction material of concrete also more and more higher.

Reinforced concrete composite structure (abbreviation SRC structures) is a kind of principal mode of steel-concrete combined structure, by In its bearing capacity is high, rigidity is big, ductility is good, anti-seismic performance is superior, fire retardant anticorrosion, is easy to the series of advantages such as construction, by It is applied to more and more widely greatly across, heavy type structure, underground, the underwater or high level and superelevation of marine engineering and earthquake/typhoon zone Layer building.Compared with steel construction, SRC structures can save great deal of steel, strengthen section rigidity, overcome steel structure fire-resistant, corrosion resistant The shortcomings of corrosion and poor durability and easy flexing unstability, the ability of steel is set to fully play；With ordinary reinforced concrete Structure (abbreviation reinforced concrete structure) is compared, and steel reinforced concrete structure can reduce the sectional dimension of component, reduces shared space, so as to increase Big building uses space；In construction, the steel skeleton of steel reinforced concrete structure can hang the bone of mould, sliding formwork as concrete in itself Frame, formwork engineering is not only enormously simplify, be also subject to the supporting of whole construction loads (including extension, sliding formwork and institute's pouring concrete) System；Further, since SRC structures have, globality is strong, the advantages that good working ductility, can substantially improve armored concrete and be broken Bad brittleness, the anti-seismic performance of structure is set to be significantly improved, bearing capacity and ductility have larger than reinforced concrete structure Improve.Therefore, in Japan and the developed country such as America and Europe, the SRC structures with good anti-seismic performance have turned into a kind of generally acknowledged new Type Aseismic Structure System, and with steel construction, timber structure, reinforced concrete structure and referred to as four big structures.China from the fifties, from The former Soviet Union has introduced SRC structures, and the middle and later periods eighties, with the fast development of Building Trade in China, SRC structures just start progressively to exist It is applied in skyscraper, such as Shanghai World Financial Center, Shenzhen DiWang Building high-rise building employs shaped steel commodity Concrete combined structure, but develop the one thousandth for being less than gross floors area using SRC construction areas from the modern whole nation.China It is the country of earthquake more than one, most areas are earthquake territory, partly positioned at highlight lines and frequently occurred earthquake area, are pushed away in these areas Wide SRC structures just have very important realistic meaning.Therefore, SRC structures have boundless application prospect in China, especially It is that (they are to be recognized with (super) high-strength high-performance concrete with the continuous enhancing of China's economic strength and (super) high-strength steel 21 century material) successful development with application, the popularization and application and progress of this structural system will be greatly facilitated.

There are some researches prove the intensity of high performance concrete is higher, and its fragility will increase, and ductility also can be poor, in height Under stress or complex stress condition, high performance concrete component will be controlled destructive process by fragility, and the reliability of work reduces.But It is that this new High Technique Concrete is applied in reinforced concrete composite structure (abbreviation SRC structures), can make the best use of the advantages and keep away It is short, overcome the weakness that normal concrete fragility is big and ductility is poor, its superior function and economic benefit is given full play to.

In SRC structures, good cementation is to ensure that SRC components Shaped Steel is assisted with concrete between shaped steel and concrete The basis of work is adjusted, three kinds of shaped steel, reinforcing bar and concrete material elements cooperate, can to resist various action effects Give full play to its advantage.But one of SRC structures and the significant difference of reinforced concrete structure are that the cohesive force between shaped steel and concrete is remote Much smaller than the cohesive force between reinforcing bar and concrete, the cohesive force of shaped steel and normal concrete is only about glued equivalent to plain steel-bar Tie the 45% of power.Domestic and international many experimental studies show, there is bond-slip phenomenon between shaped steel and concrete, and it is right The stress performance or even bearing capacity of SRC components have a significant impact.Therefore, how to ensure that shaped steel effectively cooperates with work with concrete It is made for one of emphasis of SRC structural researches.At present, to the place of bond-slip problem between shaped steel and concrete in engineering design Reason method typically has two kinds：One is adding a number of shearing connecting piece in component surface by calculating, certainly will so make The defects of into the inconvenience in construction and improving cost, and easily causing inside concrete congenital microcrack；The second is be not provided with or A small amount of shearing connecting piece is only set, the influence of bond-slip, the corresponding carrying energy for reducing component are considered in bearing capacity calculating Power, so certainly exist uneconomic factor.On the other hand, generally existing focuses on intensity and light durable in Structural Design Property phenomenon, the problem of appearance both at home and abroad in terms of many concrete structures security in use and durability. Some concrete structure engineerings are being complete due to reasons such as alkali-aggregate reaction, Chloride Attacks using insufficient design period half Complete lose uses function or even bearing capacity, and indivedual engineerings even partial collapse or total Collapse occur, cause casualties or Architectural Equipment is destroyed.Therefore, in SRC structures, the natural adhesive property between shaped steel and concrete is improved, is not set on shaped steel surface Put or only set a small amount of shearing connecting piece to ensure that shaped steel has with the research that concrete effectively cooperates by detailing requiments It is of great importance；Meanwhile the durability of concrete structure engineering also increasingly causes the close attention and great attention of people, and into For urgent problem to be solved.

The strength grade that prior art is used for the concrete of reinforced concrete composite structure has C60~C100 high-strength and high performances The technology of preparing of concrete and C110~C200 super high strength high performance concretes.Above-mentioned each strength grade concrete significantly improves Adhesive property between shaped steel and high-strength or super high strength concrete, and the durability of structure is improved, but in SRC structures The relatively small floor of some stress or the component at position, if using high-strength and high performance or super high strength high performance concrete, Can cause waste of material, it is uneconomical the problems such as.In addition, though there is also part by weak concrete high performance in the prior art Technology of preparing, but they are not directed to or not solved during for SRC structures between shaped steel and low strong high performance concrete The problem of natural adhesive property difference.

The content of the invention

It is an object of the invention to provide a kind of high-performance coagulation for reinforced concrete composite structure strength grade for C35 Soil.The concrete is applied in reinforced concrete composite structure, can (that is, shaped steel surface is not provided with or only by structure in nature Make and require to set a small amount of shearing connecting piece) under significantly improve adhesive property between shaped steel and concrete, effectively play steel with it is mixed Solidifying two kinds of respective mechanical properties of material of soil and mutual cooperative work performance, so that the significantly bearing capacity of lift structure component With performance；In addition, the concrete can improve the durability of structure, and with good service behaviour, high volume stability And economy.

In order to solve the above technical problems, what the present invention was realized in：It is strong that one kind is used for reinforced concrete composite structure C35 The high performance concrete of grade is spent, the match ratio of the concrete is (unit：kg/m³)：

Cement: fine aggregate: coarse aggregate: water: high efficiency water reducing agent: defoamer：Silicon ash：Flyash：Composite exciting agent=290: 735∶1103∶150∶4∶1∶20∶70∶2。

Described cement selects steady quality, the P.O425R Portland cements of better performances, is needed before use and poly- carboxylic Sour series high-efficiency water-reducing agent carries out compatibility test between the two, and test method uses existing building material industry standard《Cement is with subtracting Aqua compatibility test method》Method in JC/T 1083-2008, and selection is good with polycarboxylic acid series high efficiency water reducing agent compatibility Cement type.Selected cement performance index (including fineness, SO₃It is content, content of MgO, the presetting period, final setting time, 3 days strong Degree, 28 days intensity) requirement of the existing relevant criterion of country should be not less than, and from alkali content is few, the heat of hydration is low, water requiremen is also low Cement type.

Described fine aggregate should be not less than using thick river sand during particle is round and smooth, quality is hard, grading is good, the quality of sand Existing building material industry standard《Regular concrete sand, stone quality and test method standard》JC/T 52-2006 and national standard 《Building sand》High-quality sand standard specified in GB/T 14684-2011.Its modulus of fineness is 2.8, clay content and clod content Control 0.5% (in mass) below, chloride ion content control in 0.05% (in terms of the quality of dry sand) below.

Described coarse aggregate uses that quality densification is hard, intensity is high, rough surface, particle shape contain for almost spherical, gill shape Measure small, grading it is good using granite, basalt as the artificial rubble of main component, the quality of rubble should be not less than existing building materials Professional standard《Regular concrete sand, stone quality and test method standard》The regulation of the relevant criterions such as JC/T 52-2006 will Ask.The cubic compressive strength of aggregate parent rock is not lower than 1.2 times of institute's concrete batching intensity, ballast grain sizes 5mm 25mm is not to be exceeded in~25mm, maximum particle diameter, and grading is good, clay content control 1.0% (in mass) below, clod content Control 0.5% (in mass) below, pin, sheet-like particle content were not preferably greater than for 5% (in mass), and must not be mixed into weathering Particle, aggregate water soluble chloride convert into 0.02% that chloride ion content is no more than aggregate quality.When carrying out the Concrete, Fed intake using 5~Φ of continuous size fraction rubble Φ 25.

High-quality I grade of flyash that described flyash is produced using the advanced power plant of coal burning process.Its quality should be not less than National standard《For the flyash in cement and concrete》The regulation requirement of the relevant criterions such as GB/T 1596-2005, and its Fineness (0.045mm square hole screens tail over, %) should be not more than 12%, and loss on ignition should be not more than 5%, SO₃Content should be not more than 3%, 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 400m²/kg。

Described silicon ash selects the high-quality silicon ash of the advanced plant produced of smelting process.Its quality should be not less than national standard 《Mortar and concrete silicon ash》The regulation requirement of the relevant criterions such as GB/T 27690-2011, and the silica in silicon ash contains Amount should be not less than 85%, and moisture content should be not more than 3%, and loss on ignition should be not more than 4%, and chloride ion content should be not more than 0.1%, fire Mountain ash activity index should be greater than 90%, and specific surface area should be not less than 15000m²/kg。

By a large amount of tentative contrast tests and with cement compatibility test, the high efficiency water reducing agent selected by the invention is poly- High Efficient Diswater, its quality should be not less than existing national standards《Concrete admixture》The related mark such as GB 8076-2008 Accurate regulation requirement, the water-reducing rate of selected high efficiency water reducing agent should be greater than 25%.The maximum saturation of selected high efficiency water reducing agent is mixed 2.5% of amount not less than whole binder total amounts, using with mixing method, and using preceding needing and selected cement type carries out phase Compatibility test.

Described composite exciting agent (FACA) is to be applied to shaped steel coagulation by inventor place research team independent development The exciting agent of the low strong high performance concrete of native combining structure, is to pass through grinding to the pulverized burned coal ash hydration reaction characteristicses mixed with silicon ash Study carefully and recognize that its activity needs on the basis of further exciting and utilizing, 70%~75% waterglass (utilizes solid sheet NaOH and commercially available sodium silicate water glass are modulated into the waterglass that modulus is about 1.0 in proportion) and 25%~30% common two water stone Cream (CaSO₄·2H₂O a kind of chemically composited exciting agent) to proportion.Preparation method is as follows：First by solid sheet NaOH is soluble in water to be made certain density alkaline solution, then with the sodium silicate water glass of known modulus (commercial water glass Between modulus general 2.4~3.3) waterglass that the experiment that modulus is 1.0 needs is modulated into, finally answered again with common dihydrate gypsum Close to prepare and turn into required composite exciting agent (FACA).The composite exciting agent and early strong Portland cement, polycarboxylic-acid are high Effect water reducer has good compatibility.

Described defoamer selection AGITAN@P803 powder defoamers.

Described mixing water selects running water, and its quality should be not less than nation-building ministerial standard《Concrete water standard》 The regulation requirement of the relevant criterions such as JGJ 63-2006, and the alkali content of running water is not more than 1000mg/L selected by requirement.

The present invention gives the preparation side of the high performance concrete for reinforced concrete composite structure C35 strength grades Method, this method wrap up in sandstone method concrete stirring technology using improved cement, and concrete technology step is as follows：

1) first by polycarboxylic acid series high efficiency water reducing agent 4kg/m³With composite exciting agent 2kg/m³Uniformly admix load weighted water 150kg/m³In, obtain mixture；

2) 735kg/m and then according to weight proportion is added in forced mixer³Fine aggregate and step 1) mixture The 1/3 of total amount, uniform stirring 1~2 minute；

3) 1103kg/m is added³5~Φ of continuous size fraction rubble Φ 25 coarse aggregate and step 1) amount of the mixture 1/3, uniform stirring 2~4 minutes；

4) whole cementing materials are added：290kg/m³Cement, 20kg/m³Silicon ash and 70kg/m³Flyash, Even stirring 2~3 minutes；

5) 1kg/m is added³AGITAN@P803 powder defoamers and step 1) remaining mixture, 2~3 points of uniform stirring Clock, interval are stirred for 2~3 minutes to uniform, discharging, produce prepared concrete mix after 3 minutes.

The beneficial effects of the invention are as follows：

1. concrete produced by the invention is a kind of high property suitable for reinforced concrete composite structure strength grade for C35 Can concrete.The concrete is in the mechanical property (i.e. the index such as C35 intensity, plasticity) and have height that can ensure that it should possess On the basis of durability, high workability, high volume stability and economy, oneself between the concrete and shaped steel is significantly improved Right adhesive property, it is set to apply in steel reinforced concrete structure design without (or only needing by detailing requiments a little) in shaped steel table Face adds shearing connecting piece, you can ensures effective collaborative work of shaped steel and the concrete, so as to reduce working procedure, saves Steel, improve efficiency of construction, and avoid and largely set shearing connecting piece on shaped steel surface and easily cause in the concrete The defects of congenital microcrack in portion, there is significant economic benefit and construction quality improvement effect, its mechanical property contrast test It the results are shown in Table 3.In addition, relative to (super/special) high-strength high-performance concrete, the development of low strong high performance concrete can avoid mixing Solidifying soil in SRC structures in the component use at the relatively small floor of some stress or position caused by waste of material, so as to Reduce cost.

2. the water reducer selection polycarboxylic acid series high efficiency water reducing agent (water-reducing rate should be greater than 25%) used in the present invention, compared to it The water reducer of its type, good with the compatibility of early strong Portland cement, it is free of Na₂SO₄, it is mixed to can further improve this Coagulate the durability of soil.

3. the defoamer selection powder defoamer used in the present invention, model AGITAN@P803, can be stirred to concrete During formed and a large amount of microvesicles in concrete remained on after vibration compacting and carry out deaeration, explained from microcosmic angle, defoaming The use of agent can improve the microstructure of Behavior of Hardened Cement Paste to a certain extent, effectively improve its compactness, and then improve type Cohesive force between steel and concrete, enhance the durability and shear stability of concrete.

4. the alkaline composite exciting agent (FACA) of the composite exciting agent selection independent development used in the present invention, can promote calcium The generation of aluminite, make that there is certain micro-expansibility mixed with the concrete of flyash and silicon ash, improve the shrinkage of concrete. By composite exciting agent by flyash watch crystal body network structure depolymerization, so as to excite the lateral reactivity of flyash, Ke Yizeng Corrosiveness in strength fly-ash hydro-combination process using aluminosilicate as the three-D space structure vitreum of main aquation component, improve The power of positive hydration reaction, the crystal such as more C-S-H gels, drated calcium aluminate and hydrated calcium silicates are generated, promote fine coal Ash participates in early hydration process, makes full use of the seam between flyash activity micro aggregates and ball effect and silicon ash filler particles Gap, improve the performance of cementing material and reduce water consumption；And secondary hydration product fill concrete internal voids, to being prepared Early strength, later strength and the corrosion resistance of concrete increase significantly.On the other hand, the effect of composite exciting agent promotees Entered the formation of silicon ash-fly ash based mineral polymer, also significantly improved while concrete durability is improved shaped steel with Adhesive property between low strong high performance concrete.

5. it is produced by the invention for reinforced concrete composite structure strength grade be C35 high performance concrete be general Under the conditions of logical concrete production technology, and using reducing cement granules and active mineral particle as far as possible when concrete stirs everywhere What the feeding method that the cement flown upward wraps up in sandstone stirring technique was realized, preparation technology is simple and is easily achieved, and is suitable for being engineered And industrialization, it is easy to large-scale promotion application, there is preferable social benefit.

6. the former material produced by the invention for reinforced concrete composite structure strength grade for C35 high performance concrete Containing substantial amounts of flyash, silicon ash in material, they are industrial waste and smelting by-product product, and its use is made huge to environmental protection Contribution, meet sustainable development and the application of Modern Green construction material and the requirement promoted, be a kind of green concrete, Yi Zhonghuan Border friendly materials.

7. the raw material (including industrial waste) that the present invention selects are the market circulation largely produced, buy and sell product, former material Material is easy to get.

8. it is produced by the invention for reinforced concrete composite structure strength grade be C35 high performance concrete be to pass through Active mineral additives (flyash, silicon ash) are added, part of cement is replaced using equivalent method of substitution, utilizes active mineral admixture Pozzolanic reaction, enhancement effect, filing effect, durability improve the warm peak subtractive effect of effect and hydration heat of concrete, and fill Divide using caused by the compound incorporation of active mineral admixture and the composite blend of active mineral admixture and high efficiency water reducing agent Over-superimposed effect, according to they and cement granules, coarse-fine aggregate particle diameter not the same one-level the characteristics of glue in optimised coagulation soil material The grain composition of gel material part, flyash and silicon ash can the intergranular hole of filling concrete, not only make to gather materials in concrete The pore structure of interfacial structure and Behavior of Hardened Cement Paste between Behavior of Hardened Cement Paste is greatly improved, and improves the densification of Behavior of Hardened Cement Paste Degree, impermeability, while typical compact texture can expand to aggregate surface, so that concrete is more closely knit hard, concrete Mechanical property (adhesive property especially between shaped steel), endurance quality and service behaviour improve a lot.

9. the present invention, which fills appropriate flyash, can improve mobility, cohesiveness and water-retaining property that concrete mixes and stirs material, But flyash replaces part of cement to reduce the early strength of concrete to a certain extent, and mixes appropriate silicon ash, can show The intensity and durability for improving concrete are write, and secondary reaction of hydration can occur with hydrolysis product of cement Ca (OH) 2, forms glue Solidifying product, filling concrete stone structure, improve the microstructure of slurry, improve the mechanical property and durability of hardenite.Flyash With being used in conjunction with for silicon ash, concrete substrate compactness can be improved, so as to improve the caking property between shaped steel and concrete Energy.

Embodiment

The present invention is so that in nature, (that is, shaped steel surface is not provided with or only sets a small amount of shearing connection by detailing requiments Part) under significantly improve adhesive property between shaped steel and concrete, effectively play steel and two kinds of respective mechanics of material of concrete With cooperative work performance, so as to the bearing capacity and performance of significantly lift structure component, and using improve the durability of structure as Objective, to study the technology of preparing for the high performance concrete that reinforced concrete composite structure strength grade is C35.At present, The quality and intensity more and more higher of the Portland cement used in concrete, active mineral admixture used are made both at home and abroad The process technology and quality of (flyash, silicon ash etc.) are updated, in addition the research of the concrete admixture such as high efficiency water reducing agent with Using having achieved larger progress, and the research of defoamer and composite exciting agent in concrete is also just progressively being sent out with application Exhibition, so as to identify basis for the realization of the studies above objective.Meanwhile the cement consumption of the requirement of the high performance concrete It is relatively fewer, and producing cement means a large amount of discharges of carbon dioxide, therefore alleviate to a certain extent to caused by the earth Greenhouse effects；It requires to have sufficient amount and account for the high-quality active minerals such as the larger flyash of cementing material proportion, silicon ash to mix Material, it is meant that the reasonable treatment and use of industrial waste, it is beneficial to form good production cycle and environmental protection, and these are excellent The active mineral additives of matter exactly improve required for concrete material self performance.In a word, using this high performance concrete Cement can be saved, industrial waste is turned waste into wealth, extending structure engineering service life, and is finally preserved the ecological environment and natural Resource.In summary, the research and development for the high performance concrete of reinforced concrete composite structure will be preferably to use Concrete has walked out the road of a sustainable development, and the integration capability and performance of lift structure engineering are promoted steel-coagulation by it Native combining structure is in China, especially highlight lines and high level, the high-rise building in frequently occurred earthquake area, under water offshore platform or knot Structure, hypogee, contain across popularization and application in, heavy type structure, the science and technology for improving building structure in infrastructure and human settlement greatly Amount, and play that it has larger bearing capacity and rigidity, good anti-seismic performance, construction speed be fast, durable and fire resistance is good And the unique advantage such as significant social and economic benefit.Therefore, shaped steel high performance concrete combining structure has very high engineering Application value and wide market prospects.

The present invention develop be used for reinforced concrete composite structure strength grade be C35 high performance concrete, except with Normal concrete using similar material-cement, sand, rubble, outside water, be also added into its indispensable component：Efficient diminishing Agent and active mineral admixture (flyash, silicon ash), are also mixed with powder defoamer and composite exciting agent in addition.The concrete with Normal concrete is different, and its intensity and performance are greatly improved compared with normal concrete.The water of low strong high performance concrete Gray scale is generally less than 0.5, and its water-cement ratio is less than 0.4, and commonly the ratio of mud of low-strength concrete is typically more than 0.45, Gao Xing The maximum size of coarse aggregate of energy concrete is also smaller than normal concrete.Above-mentioned every difference result in high performance concrete with it is general Logical concrete has very big difference in performance, by adding active mineral additives, utilizes the volcanic ash of active mineral additives Reaction, filing effect and plasticization effect, optimize the grain composition of binder materials part in high-performance concrete material, not only make height The interfacial structure between Behavior of Hardened Cement Paste of gathering materials in performance concrete and the pore structure of Behavior of Hardened Cement Paste are greatly improved, and are improved The consistency of Behavior of Hardened Cement Paste, impermeability, while typical compact texture can expand to aggregate surface, so that high performance concrete More closely knit hard, the mechanical property (adhesive property especially between shaped steel) and endurance quality of high performance concrete have Very big raising.Meanwhile by the incorporation of powder defoamer, it can reduce and be formed in concrete whipping process and after vibration compacting The a large amount of bubbles for remaining on the interfacial transition zone in concrete in cement slurry or between cement slurry and aggregate carry out deaeration, Effectively improve its compactness, to the mechanical property (including adhesive property between shaped steel) and durability of high performance concrete The raising of energy is made that no small contribution.In addition, by the admixture of composite exciting agent, it can make concrete that there is necessarily micro- swollen Swollen property, improve the shrinkage of concrete；It can strengthen during flyash is hydrated using aluminosilicate as main aquation component The corrosiveness of vitreum, increase the activity of flyash, improve the power of positive hydration reaction, generate more C-S-H gels, The crystal such as drated calcium aluminate and hydrated calcium silicate, the intensity and corrosion resistance of institute's concrete batching are increased significantly.

Bonding between plain bar and concrete is similar, and the cohesive force between shaped steel and concrete is also mainly by chemistry Bond, frictional resistance and mechanical snap power three parts composition.Each part of cohesive force between shaped steel and concrete It is all closely related with the performance of concrete.

Chemical bond power is cement gel body in concrete in chemical adhesion strength or absorption affinity caused by shaped steel surface, its (shearing resistance) limiting value depends on the property of cement and the degree of roughness on shaped steel surface.During casting concrete, cement slurry is in steel Surface produces surface tension, and in the presence of surface tension, the cement slurry on steel surface will form self-balancing；Pour into a mould coagulation Soil will typically be vibrated, and power of vibrating (disturbance) can be strengthened and accelerate infiltration of the cement slurry to steel surface oxide layer； Cement slurry crystallizes in maintenance processes, and cement crystal forms chemical bond power.Chemical bond power is only in steel reinforced concrete structure Being originally formed under state for part is present, once (part) bond-slip on joint face occurs, cement crystal will be cut simultaneously Attrition crushing, chemical bond power are then lost.Influenceing the principal element of chemical bond power has the micro-property of concrete (concrete is mixed With the influence of material, additive), concrete strength, shaped steel steel surface degree of roughness, test specimen pour mode and vibrate degree and The maintenance in later stage and the contraction situation of concrete etc..

After chemical bond power is lost, the steel surface shape caused by the rough and other reason of steel surface Condition changes (steel surface is uneven), it is interlocked with the concrete crystal grain on contact surface, is thus formed Mechanical snap power.For the shaped steel such as plant produced and the rolled steel joist of postmenstruation processing, once bond-slip development is accelerated, Concrete crystal on shaped steel and concrete surface is crushed integration, at this moment mechanical snap power also substantial loss.Influence machine The principal element of tool snap-in force is the degree of roughness and surface appearance (corrosion degree etc.), aggregate level of shaped steel steel surface Match somebody with somebody, the force way of concrete strength and Steel Reinforced Concrete Members etc..

Shaped steel surrounding concrete is formed after the bond between shaped steel and concrete destroys to the frictional resistance of shaped steel, And mainly just played a role after mechanical snap power is lost substantially.After chemical bond power, especially mechanical snap power are lost, Due to being cut, crushed and expanded with the concrete crystal on shaped steel contact surface, the lateral confinement such as protective layer and stirrup, is incited somebody to action in addition Normal pressure is produced on the joint face of shaped steel and concrete, it is larger plus coefficient of friction on joint face, so as to form friction resistance Power.Frictional resistance all exists always after the forfeiture of chemical bond power, is the main of later stage cohesive force between shaped steel and concrete Part.The factor for influenceing frictional resistance has the shaped-steel layout and its surface characteristics of shaped steel, adhesive surface between shaped steel and concrete Size, member stress mode, aggregate grading and factor (the concrete protective thickness of shaped steel for influenceing lateral confinement Degree, stirrup ratio, concrete shrinkage) etc..

Key technical problem to be solved by this invention is, in the mechanical property that ensures high performance concrete and should possess (i.e. intensity and plasticity) and with the basis of high-durability, high workability, high volume stability and economy, significantly change (nature) adhesive property entered between concrete and shaped steel, make in steel reinforced concrete structure designs without (or only needing by construction It is required that a little) on shaped steel surface add shearing connecting piece, you can ensure there is reliable bonding and anchor between shaped steel and concrete Gu make both can harmonious, cooperation under load action.

The present invention breaks the limitation of " full sieve rice " formula, passes through orthogonal experiment and contrast from principle and design principle Experimental method, considers between high efficiency water reducing agent, defoamer, composite exciting agent three and its compatibility with cement, coarse aggregate are maximum Between particle diameter, coarse aggregate different-grain diameter and its between fine aggregate particle diameter level pairing concrete strength and performance influence and The performance factors such as the pozzolanic activity of active mineral admixture, from high-quality coarse-fine aggregate and particle diameter and grading are controlled, in high property Appropriate high efficiency water reducing agent and high-quality active mineral admixture can be mixed in concrete matched prepared material, and consider defoamer and compound The addition of exciting agent, the ratio of mud is reduced, based on the local existing material that is easy to get, do not change conventional production process, to subtract as far as possible Few cement granules and active mineral particle fly upward the side of feeding intake that sandstone stirring technique is wrapped up in using cement when concrete stirs everywhere Method, improve effect using the pozzolanic reaction of active mineral admixture, enhancement effect, filing effect, durability and high-performance is mixed The warm peak subtractive effect of the native heat of hydration is coagulated, and makes full use of the compound incorporation of active mineral admixture and active mineral admixture and height The deaeration effect of over-superimposed effect and defoamer and the activity of composite exciting agent caused by the composite blend of water reducer is imitated to swash Breaking-out use, make mechanical property (adhesive property especially between shaped steel) is good, service behaviour is excellent, excellent in durability, The strength grade suitable for the reliability application steel reinforced concrete structure of advantage of lower cost is C35 high performance concrete. The mechanical property test comparing result of the present invention is as shown in table 3.

During present invention selection raw material, raw material are not required nothing more than to be high-quality, also require to prepare used in high performance concrete Raw material are easy to get for locality.Furthermore, it is contemplated that the intensity of institute's concrete batching, plasticity and the adhesive property requirement with shaped steel, The grain composition of coarse-fine aggregate in concrete material is optimized according to maximum density theory, large or fine granule is had mutually good Good filling, to reduce the voidage of aggregate；Meanwhile the average grain diameter of general cement is 20~30 μm, the particle less than 10 μm And it is few, and the grain diameter of active mineral admixture is tiny more than cement granules particle diameter, the average grain diameter of I grade of flyash is 8 ~12 μm, space that can be between filling concrete particle, the average grain diameter of silicon ash is smaller, is 0.10~0.26 μm, can filling concrete Space between particle and fly ash grain and between fine coal grey particle, so in the high-performance concrete material prepared The grain composition of binder materials part is optimized also most important.And the outside deterioration factor (such as sulfate factor) is to mixed The aggressivity for coagulating soil is heavily dependent on the pore structure of concrete, and this is exactly the master for causing Durability of Concrete Want reason.The incorporation of active mineral admixture (flyash, silicon ash), the voidage between cement granules and interface is reduced, is made Water mudrock structure and interfacial structure are more fine and close, have blocked the permeation pathways being likely to form, so that the high-performance prepared is mixed The impermeability for coagulating soil increases substantially, water and other various etching mediums (CL-, SO42-, CO2 etc.) be difficult to enter concrete Inside, and the occurrence probability of Alkali- silica reaction and the generation probability of calcium hypochlorite can be reduced, its intensity and endurance quality obtain significantly Degree improves.I.e. when the macropore content for being more than 0.1 μm in water mudrock structure and interfacial structure is relatively low, prepared high property is beneficial to The improvement of the properties of energy concrete, otherwise, to the intensity of prepared high performance concrete, anti-permeability performance, corrosion resistance It is unfavorable with endurance quality.

It after substituting part of cement with active mineral admixture, can also be filled out the portion of water in cement granules space The mineral admixture filled in it cements out, and can increase the fluidity of cement paste.But also not all mineral blend Material all there is this significant plasticization effect, mainly due to amount of activated mineral admixture specific surface area too greatly or its Body has loose structure, although the partial moisture in cement paste can be displaced after its substitution cement, because itself absorbs water Or wetting surface needs more free water, causes the mobility of cement paste not increase.In order to ensure that developed high-performance is mixed The high workability energy of soil is coagulated, the present invention is using high efficiency water reducing agent and the method for the compound incorporation of active mineral admixture, both Under collaborative work, the subparticle of active mineral additives has not only given full play to their filing effect, and will be filled in space Among moisture cement out, water barrier thickeies between making between particle；In addition, the subparticle absorption of active mineral admixture High efficiency water reducing agent molecule, electrostatic repulsion caused by the electric double layer current potential that its surface is formed are more than universal between powder particle Gravitation, promote powder granule to disperse, and be further exacerbated by the scattered of cement granules, make the mobility of cement paste increase, so as to Effectively improve the mobility of compound；Meanwhile the compound incorporation of active mineral admixture reduces the heat of hydration, can improve mixed Coagulate the volume stability of soil；Further, since secondary hydration acts on, the compactness of concrete is improved, and interfacial structure is improved, together When the calcium hydroxide quantity of corrosion-vulnerable is reduced due to secondary response, therefore coagulation can be improved after adding coal ash and silicon ash The impermeability and Sulfate corrosion resistance and anti-magnesium corrosion etc. of soil.Because active mineral admixture specific surface area is huge, inhale Attached ability is strong, thus fly ash grain can be with the alkali in absorption cement, and is reacted with alkali and consume its quantity, free alkali number The reduction of amount can suppress or reduce alkali, and then improve the durability of concrete.

The aggregate in raw material for preparing high performance concrete should have higher relative to concrete self performance Inherent strength, toughness and stability, so that various static and dynamic stress, impact and corrasions can be resisted, without causing The decline of institute's concrete batching performance.For weak concrete when destroying, the bonding interface of cement slurry and aggregate is weak ring Section, crack is that occur along the interface of cement slurry and aggregate, and aggregate will not typically destroy, and extraneous corrode is also tended to from this Interface starts to develop.Because the surface state of different aggregates is different, adhesion strength between cement slurry and aggregate is not caused also not Identical, rubble has higher adhesion strength compared with cobble under normal circumstances；On the other hand, flyash and silicon ash content in cement slurry Ratio asynchronous adhesion strength difference is also very big, when fly ash and silicon ash, the adhesion strength between cement slurry and aggregate Significantly improved during than not mixing, and adhesion strength when when double-doped flyash and silicon ash than single fly ash has and largely carried It is high.The fine aggregate selected is using thick river during particle is round and smooth, quality is hard, grading is good, clay content is small in the research of the present invention Sand；Coarse aggregate be rough surface, fine quality, grading it is good using granite, basalt as main component artificial rubble, its Maximum particle diameter should be controlled in the range of 20~25mm.So, the uniformity of concrete has been got back further lifting, so that Concrete is more closely knit, and intensity (including adhesion strength between shaped steel) can also be further enhanced.

The present invention wraps up in sandstone method (also known as improved SEC methods) concrete stirring technology using cement in the preparation, is forcing It is stirred in formula mixer, its feeding sequence is：Polycarboxylic acid series high efficiency water reducing agent and composite exciting agent are uniformly first admixed into title In measured water, add fine aggregate and be mixed with the water of high efficiency water reducing agent and composite exciting agent water total amount 1/3 → stir (1 ~2 minutes) → add coarse aggregate and be mixed with the water of high efficiency water reducing agent and composite exciting agent water total amount 1/3 → stir (2~ 4 minutes) → add whole cementing materials (cement, silicon ash and flyash) → stir (2~3 minutes) → add defoamer with Residue is stirred for equal after being mixed with water → uniform stirring (2~3 minutes) → rest 3 minutes of high efficiency water reducing agent and composite exciting agent Even (2~3 minutes) → discharging.This technique can reduce cement granules and active mineral particle as far as possible when concrete stirs everywhere Fly upward, and the intensity (including adhesion strength between shaped steel) of prepared concrete can be improved, and prepared concrete is not Preferably there is segregation phenomenon, bleeding is few, and service behaviour is relatively preferable.

Embodiment：

(1) raw material

1. cement

Steady quality, the Qinling Mountains board PO 42.5R cement of better performances are selected, uses preceding and polycarboxylic acids high efficiency diminishing Agent carries out compatibility test between the two, and test method uses existing building material industry standard《Cement tries with water reducer compatibility Proved recipe method》Method in JC/T 1083-2008, it is good with polycarboxylic acid series high efficiency water reducing agent compatibility.Selected cement performance index Meet the requirement of the existing relevant criterion of country, its alkali content is few, the heat of hydration is low, water requiremen is also low.

2. aggregate

Using partially thick, Ba river sands during particle is round and smooth, quality is hard, grading is good, the quality of sand meets existing fine aggregate Building material industry standard《Regular concrete sand, stone quality and test method standard》JC/T 52-2006 and national standard《Building Use sand》High-quality sand standard specified in GB/T 14684-2011.Its modulus of fineness is 2.8, and clay content and clod content are controlled System 0.5% (in mass) below, chloride ion content control in 0.05% (in terms of the quality of dry sand) below.

Coarse aggregate is hard using quality densification, and intensity is high, and rough surface, particle shape is almost spherical, and pin, sheet content are small, The good artificial rubble of grading, its main component granite and basalt content (in mass) are not less than 90%.The product of rubble Matter meets existing building material industry standard《Regular concrete sand, stone quality and test method standard》The correlations such as JC/T 52-2006 The regulation requirement of standard.The cubic compressive strength of aggregate parent rock should be higher than the concrete strength prepared by more than 20%. Maximum particle diameter should be controlled between 20~25mm, and clay content is controlled below 0.5%, and the viscous content of gill shape is not preferably greater than 5%, And weathering particle must not be mixed into.

3. flyash

Using high-quality I grade of flyash of the advanced power plant's production of coal burning process.Its quality meets national standard《For cement With the flyash in concrete》The regulation requirement of the relevant criterions such as GB/T 1596-2005, (0.045mm square hole screens sieve its fineness It is remaining, %) 12% should be not more than, loss on ignition should be not more than 5%, SO₃Content should be not more than 3%, and water content should be not more than 1%, need Water ratio should be not more than 95%, and specific surface area should be greater than 400m²/kg。

4. silicon ash

Using the high-quality silicon ash of the advanced plant produced of smelting process.Its quality should be not less than national standard《Mortar and mixed Solidifying soil silicon ash》The regulation requirement of the relevant criterions such as GB/T 27690-2011, and the dioxide-containing silica in silicon ash should not be small In 85%, moisture content should be not more than 3%, and loss on ignition should be not more than 4%, and chloride ion content should be not more than 0.1%, pozzolanic activity Index should be greater than 90%, and specific surface area should be not less than 15000m²/kg。

5. high efficiency water reducing agent

6. composite exciting agent

It is applied to the low strong high-performance of reinforced concrete composite structure from by inventor place research team independent development The exciting agent of concrete is in the research passed through to the pulverized burned coal ash hydration reaction characteristicses mixed with silicon ash and recognizes that its activity needs On the basis of further exciting and utilize, 70%~75% waterglass (utilizes solid sheet NaOH and commercially available sodium metasilicate water glass Glass is modulated into the waterglass that modulus is about 1.0 in proportion) and 25%~30% common dihydrate gypsum (CaSO₄·2H₂O) in proportion Coordinate a kind of chemically composited exciting agent formed.The composite exciting agent subtracts with early strong Portland cement, polycarboxylic acids high efficiency Aqua has good compatibility.

The different ratio of table 1FACA exciting agents

7. mixing water

It is mixing water from running water, its quality meets Minstry of Housing and Urban-Rural Development of People Republic of China's ministerial standard《Concrete mixing water supply standard》JGJ The regulation requirement of the relevant criterions such as 63-2006, and alkali content is less than 1000mg/L.

(2) match ratio

The present invention provides for the strength grade that will be applied in steel reinforced concrete structure for C35 high performance concrete Match ratio it is as shown in table 2.

Table 2 is used for the high-performance concrete mix (unit of reinforced concrete composite structure：kg/m³)

(3) stirring technique

The invention wraps up in sandstone method concrete stirring technology using cement, and concrete technology step is as follows：

First by polycarboxylic acid series high efficiency water reducing agent 4kg/m³With composite exciting agent 2kg/m³Uniformly admix load weighted water 150kg/ m³In, 735kg/m is added in forced mixer according to weight proportion³Fine aggregate and be mixed with high efficiency water reducing agent and it is compound swash Send out the 1/3 water about 52.0kg/m of agent water total amount³, uniform stirring is after 1~2 minute, addition 1103kg/m³Coarse aggregate and mix There is the 1/3 water about 52.0kg/m of high efficiency water reducing agent and composite exciting agent water total amount³, uniform stirring is after 2~4 minutes, then adds Enter whole cementing materials：290kg/m³Cement, 20kg/m³Silicon ash and 70kg/m³Flyash, uniform stirring 2~3 minutes Afterwards, 1kg/m is added³AGITAN@P803 powder defoamers and the remaining water for being mixed with high efficiency water reducing agent and composite exciting agent about 52.0kg/m³, uniform stirring 2~3 minutes, 2~3 minutes are stirred for after resting 3 minutes to uniform, discharging.

This technique can reduce cement granules as far as possible and superfine active mineral grain is flown upward everywhere when concrete stirs, and Can improve the intensity (including adhesion strength between shaped steel) of prepared concrete, and prepared concrete should not occur from Phenomenon is analysed, bleeding is few, and service behaviour is relatively preferable.

(4) mechanical property test Comparative result

The high-performance that the strength grade suitable for reinforced concrete composite structure prepared according to above-mentioned match ratio is C35 Concrete and the mechanical property comparative test result of normal concrete (strength grade is C35 concrete) are as shown in table 3.

The mechanical performance of concrete comparative test result of table 3

From table 3 it can be seen that the high performance concrete that the strength grade prepared by the technology is C35, is realized in energy really Protect mechanical property (i.e. the index such as C35 intensity, plasticity) that it should possess and with high-durability, high reliability, high workload On the basis of property, high volume stability and economy, (nature) adhesive property for being significantly improved between concrete and shaped steel makes Shearing connecting piece is added on shaped steel surface without (or only needing by detailing requiments a little) in steel reinforced concrete structure design, i.e., Effective collaborative work of shaped steel and concrete can be ensured, so as to reduce working procedure, saved steel, improve construction effect Rate, and avoid the defects of shearing connecting piece is largely set on shaped steel surface and easily causes inside concrete congenital microcrack； In addition, for prior art is used for the high-strength high-performance concrete of reinforced concrete composite structure, strength grade C35 High performance concrete development, be SRC structures in the cost performance optimization design of the relatively small floor of stress or placement members carry Premise has been supplied, the problem of he not only solves natural adhesive property difference between shaped steel and low strong high performance concrete, and solve Waste of material, uneconomical etc. can be caused by being used for the high-strength high-performance concrete of reinforced concrete composite structure using prior art Problem, so as to have higher engineering application value and wide market prospects.

Claims

A kind of 1. concrete for reinforced concrete composite structure C35 strength grades, it is characterised in that the concrete according to kg/m³Match ratio be：

Cement: fine aggregate: coarse aggregate: water: high efficiency water reducing agent: defoamer：Silicon ash: flyash：Composite exciting agent=290: 735: 1103∶150∶4∶1∶20∶70∶2；

The cement selects P.O425R Portland cements；

The fine aggregate is using thick river sand during particle is round and smooth, quality is hard, grading is good, modulus of fineness 2.8；

The cubic compressive strength of the coarse aggregate parent rock is not lower than 1.2 times of institute's concrete batching intensity, rubble grain Footpath is 5mm~25mm, and 25mm is not to be exceeded in maximum particle diameter, and grading is good, and clay content is controlled below 1.0% in mass, mud Block content is controlled below 0.5% in mass, and pin, sheet-like particle content are not preferably greater than 5% in mass, and must not be mixed into wind Change particle, aggregate water soluble chloride converts into 0.02% that chloride ion content is no more than aggregate quality；Carry out the Concrete When, fed intake using 5~Φ of continuous size fraction rubble Φ 25；

The high efficiency water reducing agent selects polycarboxylic acid series high efficiency water reducing agent, and water-reducing rate is more than 25%；The defoamer selection AGITAN@ P803 powder defoamers；

The silicon ash selects high-quality silicon ash, and the dioxide-containing silica in silicon ash should be not less than 85%, and moisture content should be not more than 3%, loss on ignition should be not more than 4%, and chloride ion content should be not more than 0.1%, and pozzolanic activity index should be greater than 90%, compare surface Product should be not less than 15000m²/kg；

High-quality I grade of flyash that the flyash is produced using the advanced power plant of coal burning process, and its fineness is with 0.045mm square holes 12% should be not more than by tailing over meter, and loss on ignition should be not more than 5%, SO₃Content should be not more than 3%, and water content should be not more than 1%, Water demand ratio should be not more than 95%, and specific surface area should be greater than 400m²/kg；

The composite exciting agent selection self-control flyash composite exciting agent FACA, by the water glass solution that percentage by weight is 75% With 25% dihydrate gypsum CaSO₄·2H₂O is formulated；

The composite exciting agent is prepared by following methods：

Certain density alkaline solution is made by solid sheet NaOH is soluble in water first, then with water that modulus is 2.4~3.3 Glass mixes, and it is 1.0 water glass solutions to be modulated into modulus, takes 75% water glass solution and 25% dihydrate gypsum CaSO₄· 2H₂O is mixed, and produces composite exciting agent FACA；

The concrete slump is 120mm, cubic compressive strength 41.32MPa, split tensile strength 3.86MPa, with shaped steel Between adhesion strength be 2.7Mpa, concrete infiltration grade is IV grade.
2. a kind of preparation method of the concrete for reinforced concrete composite structure C35 strength grades described in claim 1, Characterized in that, this method wraps up in sandstone method concrete stirring technology using improved cement, comprise the steps：

1) first by polycarboxylic acid series high efficiency water reducing agent 4kg/m³With composite exciting agent 2kg/m³Uniformly admix load weighted water 150kg/m³ In, obtain mixture；

2) 735kg/m and then according to weight proportion is added in forced mixer³Fine aggregate and step 1) amount of the mixture 1/3, uniform stirring 1~2 minute；

3) 1103kg/m is added³5~Φ of continuous size fraction rubble Φ 25 coarse aggregate and step 1) amount of the mixture 1/3, Even stirring 2~4 minutes；

4) whole cementing materials are added：290kg/m³Cement, 20kg/m³Silicon ash and 70kg/m³Flyash, uniformly stir Mix 2~3 minutes；

5) 1kg/m is added³AGITAN@P803 powder defoamers and step 1) remaining mixture, uniform stirring 2~3 minutes, 2~3 minutes were stirred for after 3 minutes to uniform, discharging, produces prepared concrete mix.