RPC and preparation and constructional method for building reinforce
Technical field
The present invention relates to its preparation of RPC and constructional method that a kind of building reinforce is used.
Background technology
Concrete building structures is as the rapidest, the most widely used a kind of structural system of technical development in 20th century building fields, because a variety of causes need to be reinforced reparation in its cycle in work-ing life, to maintain the normal performance of safety and the function of structure.In European and American developed countries, the investment for building reinforce transformation has at present accounted for the more than 1/2 of national construction industry gross investment.Department of Labor's door was once foretold in an industry prediction address in 20 end of the centurys: building maintenance is reinforced industry and will be 21 century one of the most popular industry.
China, from since the establishment of the nation, particularly carries out reforms after opening the end of the seventies in last century, and various building constructions, bridge, dykes and dams, tunnel and city technological facilities quantity sharply increase.According to relevant departments' statistics, the total area of the various buildingss that current China is existing surpasses 10,000,000,000 m
2, wherein the overwhelming majority is concrete structure, and has at least 50% buildings to use more than 20 years.In use, due to reasons such as self aging, various disaster and artificial damages, make buildings constantly produce various structural safety hidden danger.In addition, in China's existing building, old structure design can not meet the demand of current use in function, improving constantly along with China's Economic development and living standards of the people particularly, reconstruction of the old city town in recent years almost becomes the common issue in each big or middle city, has a considerable amount of old buildings need to meet by strengthening reconstruction the needs of new function.For this reason, country will drop into every year substantial contribution and transform for various building structure strengthenings, and these have all stimulated developing rapidly of building reinforce transformation industry, also for industry provides wide development platform.
As the major measure of building reinforce transformation, at present the most frequently used has steel bonding technology, affixing carbon fabric, carbon fiber board and strengthens the methods such as member section.Strengthening member section can cause effective usage space reduction and effective usable floor area of structure to reduce.Steel bonding and sticking carbon fiber, not only cost is high, cost is wayward, also be difficult to organically blend with reinforcing object, and there is catabiosis in the structure glue of using in taping process, add steel plate, carbon fiber and concrete structure thermal property inconsistent, in life-time service process, have all the time the risk of unsticking.
RPC is mainly used in the fields such as prestressed structure, pre-manufactured product member, anti-seismic structure and concrete filled steel tube.Yet the starting material that existing RPC formula is used are various, although it has high intensity, required curing condition is comparatively harsh, and resulting cost is higher, is not suitable for building reinforce.
To sum up, how to develop and a kind ofly can be exclusively used in structural strengthening, consolidation effect is good, can combine together with existing building is organic, again can constructability, and economical and practical material is the inexorable trend of reinforcing industry development.
Summary of the invention
The invention provides RPC and preparation and constructional method for a kind of building reinforce, solve existing building strengthening reconstruction technical costs high, reinforcement material is difficult to organically blend with reinforcing object, caducous technical problem in use procedure.
The technical solution adopted for the present invention to solve the technical problems is:
This building reinforce RPC, its raw material forms as follows by weight ratio:
50~80 parts of cement;
15~40 parts of fly ash micro-spheres;
5~13 parts of silicon ashes;
35~80 parts, river sand;
20~65 parts of quartz sands;
10~20 parts, water;
10~30 parts of steel fibers;
1~2 part of chemical additive.
Described cement is silicate cement or ordinary Portland cement, and strength grade is not less than 42.5 grades.
Described fly ash micro-sphere is white or grayish fly ash micro-sphere, and loss on ignition is lower than 1%, specific surface area>=10000 cm
2/ g.
The SiO of described silicon ash
2content is greater than 90%, specific surface area>=18000 cm
2/ g.
Described river sand is conventional concrete mixing river sand, and its particle diameter is 0.15mm ~ 2.36mm.
Described quartz sand is commercially available common quartz sand, its SiO
2content>=98%, median size is 0.1mm ~ 0.3mm.
Described steel fiber is commercially available copper facing or nickel plated steel fibers, length 10mm ~ 15mm, length-to-diameter ratio 1:120 ~ 1:60.
Described chemical additive is high-efficiency water-reducing agent of poly-carboxylic acid, and its water-reducing rate is not less than 25%, or the mixture of high-efficiency water-reducing agent of poly-carboxylic acid and other additives, and other additives are one or more the mixture in plasticity-retention agent, air entrapment agent and defoamer.
The preparation method of RPC for this building reinforce, first powder raw material cement, fly ash micro-sphere, silicon ash are added in mixer and preferentially stirred, then add river sand, quartz sand, steel fiber to stir, add again water and chemical additive to stir, through moulding, vibrate and conventional maintenance, can obtain finished product.
The constructional method of RPC for this building reinforce, construction procedure is as follows:
Step 1: concrete building structures is treated to surface, reinforcing portion position dabbing, control and reject concrete thickness in dabbing process, to reduce the destruction to original structure;
Step 2: the bar planting of holing on concrete building structures roughened surface respectively, reinforcing steel bars exposed is partly less than the body structure surface after reinforcing;
Step 3: cleaning roughened surface, and to it and soak;
Step 4: treat reinforcing position and carry out form for seal, then inject above-mentioned building reinforce by RPC and vibrate, its RPC is built thickness according to calculating and determine early stage;
Step 5: meet after form removal requirement by RPC hardness until building reinforce, by form removable, and carry out conventional maintenance to reinforcing position.
Beneficial effect of the present invention is as follows:
Building reinforce provided by the invention not only has higher ultimate compression strength by RPC, and its starting material that adopt can be good at being combined with having concrete, thereby has greatly improved the cohesive strength of new-old concrete.
Raw materials of the present invention is simple, and coarse aggregate used is river sand, has reduced cost, can obtain the RPC material of the nearly 180MPa of intensity under normal temperature maintenance simultaneously, and this is that other technologies institute is irrealizable.
Compare with the carbon fiber reinforcement, the outer sticking steel plate technology that generally adopt in current structural strengthening industry, building reinforce provided by the invention has solved the problems such as reinforcement cost is high, poor durability by RPC, and its cost is only 1/20th of steel.
Building reinforce provided by the invention not only has advantages of that by RPC good fluidity, plasticity-are strong, good with existing structure cohesiveness, and there is close linear expansivity with existing concrete structure, itself shrinkage in process of setting can make RPC material and existing structure that the later stage builds be closely as one, and has more increased the globality of structure.
Building reinforce of the present invention is slightly different from common ready mixed concrete order of addition(of ingredients) by order of addition(of ingredients) in RPC preparation method, can reach better mixed effect.
Building reinforce provided by the invention is simple by RPC construction technology, only needs that it is carried out to conventional maintenance and just can reach the consolidation effect of expection after moulding, and maintenance environment is identical with common ready mixed concrete.
Embodiment
For a better understanding of the present invention, below in conjunction with embodiment, further illustrate content of the present invention, but content of the present invention is not only confined to the following examples.
Embodiment 1 ~ 3, this building reinforce RPC, and each starting material are as shown in table 1 by weight ratio.
Each starting material of table 1 by weight ratio
Numbering |
Water |
Cement |
Fly ash micro-sphere |
Silicon ash |
River sand |
Quartz sand |
Steel fiber |
Chemical additive |
Powder/fine aggregate |
Embodiment 1 |
15 |
65 |
22.8 |
12.2 |
70 |
30 |
17 |
1.8 |
1:1 |
Embodiment 2 |
15 |
70 |
21 |
9 |
65 |
35 |
17 |
1.8 |
1:1 |
Embodiment 3 |
15 |
70 |
21 |
9 |
60 |
40 |
17 |
1.8 |
1:1 |
Wherein:
Cement is ordinary Portland cement, and strength grade is 42.5;
Fly ash micro-sphere is white or light grey fly ash micro-sphere, and loss on ignition is lower than 1%, specific surface area>=10000cm
2/ g;
Silicon ash is SiO
2the silicon ash that content is greater than 90%, specific surface area>=18000cm
2/ g;
The thin river sand that sand grains footpath, river is 0.3mm ~ 1.18mm;
Quartz sand is SiO
2the quartz sand of content>=98%, median size 0.15mm;
Steel fiber is commercially available copper plated steel fiber, length 12mm, length-to-diameter ratio 1:120;
Chemical additive is high-efficiency water-reducing agent of poly-carboxylic acid, light yellow, solid content 24%, and water-reducing rate is 30%;
Mixing water is the mixing water of cleanliness without any pollution, as drinking public water supply;
Shaping test piece is of a size of 40 * 40 * 160mm.
According to the performance requriements of building reinforce material, building reinforce is carried out to correlated performance detection by RPC, result is as shown in table 2.
RPC correlated performance detected result for table 2 building reinforce
Known by the detected result in table 2, described in embodiment 1 ~ 3, building reinforce all has good mobility by RPC, constructs very convenient; Under normal temperature curing condition, 28d ultimate compression strength can be up to 179.6MPa for it, and folding strength, up to 38.8MPa, can meet the requirement of reinforcement material to intensity and toughness.
Embodiment 4 ~ 6, this building reinforce RPC, and each starting material are as shown in table 3 by weight ratio.
Each starting material of table 3 by weight ratio
Wherein:
Cement is ordinary Portland cement, and strength grade is 42.5;
Fly ash micro-sphere is white or light grey fly ash micro-sphere, and loss on ignition is lower than 1%, specific surface area>=10000cm
2/ g;
Silicon ash is SiO
2the silicon ash that content is greater than 90%, specific surface area>=18000 cm
2/ g;
The thin river sand that sand grains footpath, river is 0.3mm ~ 2.36mm;
Quartz sand is SiO
2the quartz sand of content>=98%, median size 0.15mm;
Steel fiber is commercially available copper plated steel fiber, length 12mm, length-to-diameter ratio 1:120;
Chemical additive is high-efficiency water-reducing agent of poly-carboxylic acid, light yellow, solid content 24%, and water-reducing rate is 30%;
Mixing water is the mixing water of cleanliness without any pollution, as drinking public water supply;
Shaping test piece is of a size of 40 * 40 * 160mm.
According to the performance requriements of building reinforce material, building reinforce is carried out to correlated performance detection by RPC, result is as shown in table 4.
RPC correlated performance detected result for table 4 building reinforce
The fine sand particle diameter adopting in embodiment 4 ~ 6 is 0.3mm ~ 2.36mm, different from embodiment 1 ~ 3, known from embodiment 4 ~ 6, improve fine aggregate and powder ratio and increase the workability that sand grains footpath, river does not have significantly to reduce RPC, its ultimate compression strength is slightly improved, 28d ultimate compression strength can be up to 179.8MPa, and folding strength slightly declines, and 28d folding strength can reach 33.8MPa.
Embodiment 7 ~ 9, this building reinforce RPC, and each starting material are as shown in table 5 by weight ratio.
Each starting material of table 5 by weight ratio
Wherein:
Cement is ordinary Portland cement, and strength grade is 42.5;
Microballon is white or light grey fly ash micro-sphere, and loss on ignition is lower than 1%, specific surface area>=10000cm
2/ g;
Silicon ash is SiO
2the silicon ash that content is greater than 90%, specific surface area>=18000 cm
2/ g;
The thin river sand that sand grains footpath, river is 0.3mm ~ 2.36mm;
Quartz sand is SiO
2the quartz sand of content>=98%, median size 0.15mm;
Steel fiber is commercially available copper plated steel fiber, length 12mm, length-to-diameter ratio 1:120;
Chemical additive is high-efficiency water-reducing agent of poly-carboxylic acid, light yellow, and solid content is 24%, and water-reducing rate is 30%;
Mixing water is the mixing water of cleanliness without any pollution, as drinking public water supply;
Shaping test piece is of a size of 40 * 40 * 160mm.
According to the performance requriements of building reinforce material, building reinforce is carried out to correlated performance detection by RPC, result is as shown in table 6.
RPC correlated performance detected result for table 6 building reinforce
The fine sand particle diameter adopting in embodiment 7 ~ 9 is 0.3mm ~ 2.36mm, different from above-described embodiment, in embodiment 7 ~ 9, increase the workability that volume content of steel fibers and sand grains footpath, river can reduce RPC, but its ultimate compression strength and folding strength all have significantly raising, 28d ultimate compression strength can be up to 191.3MPa, and folding strength is up to 45.8MPa.