CN111574167B - Seawater corrosion resistant concrete member and preparation method thereof - Google Patents
Seawater corrosion resistant concrete member and preparation method thereof Download PDFInfo
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- CN111574167B CN111574167B CN202010458660.XA CN202010458660A CN111574167B CN 111574167 B CN111574167 B CN 111574167B CN 202010458660 A CN202010458660 A CN 202010458660A CN 111574167 B CN111574167 B CN 111574167B
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
- C04B28/08—Slag cements
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
- C04B28/06—Aluminous cements
- C04B28/065—Calcium aluminosulfate cements, e.g. cements hydrating into ettringite
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
- C04B2111/20—Resistance against chemical, physical or biological attack
- C04B2111/24—Sea water resistance
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2201/00—Mortars, concrete or artificial stone characterised by specific physical values
- C04B2201/50—Mortars, concrete or artificial stone characterised by specific physical values for the mechanical strength
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Abstract
The invention provides a concrete member resistant to seawater and high-salt environment erosion, which is cast by raw materials comprising FRP ribs and ettringite cement concrete. The ettringite cement concrete comprises, by weight, 10-20% of ettringite cement, 25-40% of fine aggregate, 40-55% of coarse aggregate, 4-10% of water and 0.05-0.2% of an additive; the ettringite cement is slag sulphoaluminate cement or high belite sulphoaluminate cement; the fine aggregate is any one or a mixture of river sand and sea sand; the raw material components preferably consist of 14 to 19 percent of ettringite cement, 27 to 36 percent of fine aggregate, 43 to 52 percent of coarse aggregate, 6 to 7.5 percent of water and 0.1 to 0.2 percent of additive. Because the ettringite cement concrete is not easy to be corroded by sulfate and the hardened structure has excellent sulfuric acid corrosion resistance, the concrete member can solve the problems of poor seawater corrosion resistance, insufficient durability and the like of the existing marine concrete.
Description
Technical Field
The invention relates to a concrete member, in particular to an FPR (prestressed concrete) rib-ettringite cement concrete member, a preparation method thereof and application thereof in ocean construction engineering.
Background
The marine concrete material faces serious durability problem, at present, the cementing material for the marine engineering usually adopts a silicate cement system, and the structural tensile stress is borne by the configured steel bars. Because the seawater contains a large amount of SO4 2-And Cl-，SO4 2-Will mix with Ca (OH) in the concrete2And C-S-H reactions cause deterioration of concrete properties; cl-When the Portland cement is added into concrete, reinforcing steel bars can be corroded, the durability of a material building structure is seriously influenced, and the structure becomes alkaline after the Portland cement is hydrated, so that the marine environment can be influenced to a certain extent. Therefore, the application of the traditional silicate system cement and steel bars to the ocean engineering concrete structure has obvious defects.
The slag sulphoaluminate cement is a novel cementing material which takes blast furnace granulated slag as a main raw material (about 80 percent) and takes gypsum and high belite sulphoaluminate cement as an excitant, the strength of the cement is close to that of portland cement, and the cement has the advantages of low hydration heat, good impermeability, strong sulfate erosion resistance and the like,and realizes the utilization of solid waste resources. The slag sulphoaluminate cement is used for replacing the portland cement to prepare the concrete, and the FRP ribs are used for replacing the reinforcing steel bars, so that Cl can be avoided-The corrosion of the steel bar caused by corrosion can improve the seawater corrosion resistance and the long-term durability of the concrete.
Therefore, slag sulphoaluminate cement is needed to be used as a cementing material, and an FRP rib-ettringite cement concrete member is researched and developed, and the member is characterized in that the adopted cement hydration product mainly contains ettringite and has excellent seawater corrosion resistance and high salt corrosion resistance.
In view of the above, the present invention is particularly proposed.
Disclosure of Invention
A first object of the present invention is to provide an ettringite cement concrete which is less likely to be corroded by sulfate and has an excellent sulfuric acid corrosion resistance in a hardened structure.
The second purpose of the invention is to provide an FRP rib-ettringite cement concrete member, which solves the problems that the existing marine concrete has poor seawater corrosion resistance and insufficient durability, and the FRP rib is corroded by the high-alkali environment of the existing portland cement concrete.
In order to achieve the above purpose of the present invention, the following technical solutions are adopted:
the ettringite cement concrete consists of raw material components including, by weight, 10-20% of ettringite cement, 25-40% of fine aggregate, 40-55% of coarse aggregate, 4-10% of water and 0.05-0.2% of additive.
The optimized ettringite cement concrete comprises, by weight, 14-19% of ettringite cement, 27-36% of fine aggregate, 43-52% of coarse aggregate, 6-7.5% of water and 0.1-0.2% of an additive.
In the ettringite cement concrete of the present invention, the ettringite cement means that the main hydration product is ettringite and does not contain Ca (OH)2The cement of (1). Preferably a slag sulphoaluminate cement or a high belite sulphoaluminate cement.
The preferable ettringite cement concrete has the water-to-cement ratio of 0.3-0.5; more preferably 0.3 to 0.45; most preferably 0.33.
In a preferred embodiment of the present invention, the fine aggregate is one or a mixture of two of river sand and sea sand.
When the fine aggregate is only river sand, the river sand is more preferably 28.6 to 34.7 percent of the weight of the ettringite cement concrete.
When the fine aggregate is a mixture of river sand and sea sand, the weight of the sea sand in the mixture is more preferably 25-75%, and the weight of the sea sand is more preferably 25-50%; most preferably, the sea sand comprises 50% by weight.
The water can be selected from one or more of seawater, river water, lake water or tap water.
On the basis, the invention further provides a concrete member resistant to seawater and high-salt environment corrosion, which is cast by raw materials comprising FRP ribs and the ettringite cement concrete. The invention is called FRP rib-ettringite cement concrete member.
In the FRP rib-ettringite cement concrete member of the invention, the FRP rib mainly bears tensile stress in the structure, and the ettringite cement concrete mainly bears compressive stress.
In the FRP rib-ettringite cement concrete member preferred in the invention, the FRP ribs account for 2-5% (wherein the structural ribs account for 1-3%, the longitudinal ribs account for 1-2%) and the ettringite cement concrete accounts for 95-98% in volume percentage.
In the more preferable FRP rib-ettringite cement concrete member of the invention, the FRP ribs account for 2-3% (wherein the structural ribs account for 1-2%, the longitudinal ribs account for 1%) and the ettringite cement concrete accounts for 97-98% in volume percentage.
In the more preferable FRP rib-ettringite cement concrete member of the invention, in the raw materials, the FRP ribs account for 2-3 percent (wherein, the structural ribs account for 1-2 percent, the longitudinal ribs account for 1 percent), and the ettringite cement concrete accounts for 97-98 percent; the water-to-gel ratio of the ettringite cement concrete is 0.4-0.5; most preferably 0.45.
In the preferred FRP bar-ettringite cement concrete member of the present invention, the FRP bar is selected from any one or a combination of two or more of basalt fiber-reinforced plastic bars, glass fiber-reinforced plastic bars, carbon fiber-reinforced plastic bars, and aramid fiber-reinforced plastic bars; more preferably, glass fiber reinforced plastic ribs or basalt fiber reinforced plastic ribs; most preferably basalt fibre reinforced plastic ribs.
In a preferred embodiment of the present invention, the FRP bar-ettringite cement concrete member is cast from the following raw materials by volume percentage: 2-3% of basalt fiber reinforced plastic ribs (wherein, the structural ribs are 1-2%, the longitudinal ribs are 1%) and 97-98% of ettringite cement concrete; the ettringite cement concrete consists of 14 to 19 percent of ettringite cement, 27 to 36 percent of fine aggregate, 43 to 52 percent of coarse aggregate, 6 to 7.5 percent of water and 0.1 to 0.2 percent of additive, and the water-to-gel ratio is 0.45; the fine aggregate is a mixture of sea sand and river sand, and the weight percentage of the sea sand is 25-100%; preferably, the weight percentage of the sea sand is 50 to 100 percent; most preferably, the sea sand is 50% by weight.
In another preferred embodiment of the present invention, the FRP bar-ettringite cement concrete member is cast from the following raw materials in percentage by volume: 2% -3% of FRP (wherein, the structural reinforcement is 1% -2%, the longitudinal reinforcement is 1%) and 97% -98% of ettringite cement concrete; the FRP ribs are glass fiber reinforced plastic ribs or basalt fiber reinforced plastic ribs; the ettringite cement concrete consists of 14 to 19 percent of slag sulphoaluminate cement, 27 to 36 percent of fine aggregate, 43 to 52 percent of coarse aggregate, 6 to 7.5 percent of water and 0.1 to 0.2 percent of additive, and the water-to-glue ratio is 0.45; the fine aggregate is a mixture of sea sand and river sand, and the weight percentage of the sea sand is 25-100%; preferably, the weight percentage of the sea sand is 25 to 50 percent; most preferably, the sea sand is 50% by weight.
On the basis, the invention also provides a method for pouring the FRP bar-ettringite cement concrete member, which comprises the following concrete pouring steps (flow path):
1) setting a template according to a set specification;
2) performing FRP rib manufacturing and installation in the template arranged in the step 1);
3) mixing to prepare the ettringite cement concrete;
4) pouring and compacting the ettringite cement concrete mixed in the step 3) in the template obtained in the step 2);
5) and 4) curing and stripping the poured and compacted concrete according to a conventional method to obtain the concrete member.
The template for pouring in the step 1) can adopt a template which is commonly used for concrete structure pouring construction such as a shaped steel mould and the like; 2) the FRP ribs are arranged at the position of a tension area of the structure so as to ensure that the tensile function of the FRP ribs is fully exerted; 3) the mixing is to fully and uniformly mix the ettringite cement, the fine aggregate, the coarse aggregate and other powder, add water and the admixture, mix and mix; 4) Pouring the mixture in 3) into the formwork with the FRP ribs obtained in 2) after mixing, and fully vibrating and compacting; 5) and (4) curing the concrete poured and compacted in the step 4) with a mould until the strength meets the requirement, and then removing the mould.
Compared with the prior art, the invention has the following beneficial effects:
1) the invention takes ettringite cement such as slag sulphoaluminate cement or high belite sulphoaluminate cement and the like as cementing materials to prepare a high-durability building material, and in the hydration process, the ettringite cement hydration products mainly comprise ettringite and hydrated calcium sulphoaluminate, and Ca (OH) is not contained2And C-S-H is less and is not easy to be corroded by sulfate. The fine ettringite generated by hydration has micro-expansibility, so that the pores of the matrix are effectively filled, the compactness of the material is increased, and the anti-permeability performance of the material is improved. The hardened structure has excellent resistance to corrosion by sulfuric acid.
2) In the invention, the FRP ribs are adopted to bear the tensile stress of the structure, and the FRP has strong Cl resistance-The corrosion capability, consequently use in the marine structure can show the durability that improves the structure, and FRP muscle intensity is higher, can satisfy the design requirement of ocean engineering structure.
3) In the hydration process of the ettringite cement, Ca (OH) in the material2Takes part in the reaction and is consumed, so that Ca (OH) is not contained in the material after hydration and hardening2The base body has low alkalinity, can not cause the alkali corrosion of the FRP rib when being used together with the FRP rib, and can not have OH in the service process-The dissolution has small influence on the pH value of the seawater environment.
4) The inventor of the invention discovers through experimental verification that the later-stage compression strength and the breaking strength of the concrete can be obviously improved when the sea sand replaces river sand in a specific range under the condition that the water-cement ratio and the coarse aggregate are not changed in the calcium alum stone concrete material. The reason is that the compactness and the strength of the matrix are further improved because chloride ions can react with calcium sulphoaluminate to generate gelled products.
5) The slag sulphoaluminate cement serving as a concrete cementing material contains gypsum and high belite aluminate cement clinker, and the gypsum and the high belite sulphoaluminate cement clinker serve as granulated blast furnace slag excitant, so that a new technical thought is provided for actively developing special cement in China, improving the characteristics of the special cement and improving the technical defects of the existing super-sulfate cement.
Drawings
FIG. 1 is a schematic structural view of a concrete member according to embodiments 10 to 19 of the present invention, and A, B are respectively a front view and a side view of the member. The various symbols in the figure are illustrated as follows: 1-concrete cube, 2-single reinforcement, 11-stirrup, 21-loading end, 22-free end, F and arrow representing the application direction of the drawing force.
Fig. 2 is a schematic structural view of concrete beam members according to embodiments 20 to 29 of the present invention, and A, B are a longitudinal section and a cross-sectional view of the beam members, respectively. The various symbols in the figure are illustrated as follows: the first and second represent FRP ribs, the third represents hooping, and the O, delta, P/2 and arrows represent the action point and direction of force in the four-point bending test.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to examples, but it will be understood by those skilled in the art that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
Examples 1-9 ettringite cement-based concrete and Performance testing thereof
Ettringite cement concretes of examples 1 to 9 were prepared according to the mixing ratios listed in table 1 below. The slag sulphoaluminate cement is prepared by mixing and grinding 60-90% of granulated blast furnace slag, 10-30% of anhydrite and 5-10% of high belite sulphoaluminate cement clinker in percentage by weight.
TABLE 1 mixing ratio of Calcite concrete in examples 1-9
In the embodiment 1-3, the slag sulphoaluminate cement-based ettringite concrete is prepared according to different water-cement ratios; in embodiments 4 to 7, river sand is replaced by partial sea sand, wherein the weight ratio of the sea sand to the river sand is as follows: 1:0, 0.25:0.75, 0.5:0.5, and 0.75: 0.25.
Concrete based on ordinary 42.5 portland cement of comparative examples 1 to 3 was prepared according to the mix ratio listed in table 2 below.
TABLE 2 composition of silicate cement concrete in comparative examples 1 to 3
The slag sulphoaluminate cement-based ettringite concrete provided in examples 1 to 9 was used to prepare test pieces, which were recorded as test groups 1 to 9. The portland cement concrete provided by comparative examples 1-3 was proportioned to prepare test pieces, which were recorded as control groups 1-3, and each mechanical property of each group of test pieces was tested respectively and the performance data is listed in table 3.
TABLE 3 Performance test results of the test groups 1-9 and the control groups 1-3
As can be seen from table 3 above, the post-performance after 28 days for each test piece of the test group is significantly higher than that of each control group. Wherein, the test group 1 with the water-cement ratio of 0.33 and the test groups 5 and 6 with the water-cement ratio of 0.5 and the river sand of 25 to 50 percent replaced by the sea sand have the most excellent compression strength and breaking strength at 90 days; and the compression strength and the breaking strength of the test groups 2, 4 and 6 are obviously improved in later period compared with the control groups 1-3 with the same water-cement ratio and the same sandstone dosage. The test groups 8 and 9 are significantly superior to the control groups in both early strength and late strength.
Example 10 to 19 FRP Rib-Aluminonite Cement concrete Member and Performance test thereof
The FRP rib-ettringite concrete members of examples 10 to 19 were obtained by casting according to the raw materials and mixing ratios listed in Table 4 below. The method comprises the following specific steps of:
1) adopting a 100mm cubic steel mould and a wood template, wherein round holes are symmetrically formed in two sides of the template and used for penetrating reinforcing bars with different diameters;
2) in order to prevent the concrete test piece from cracking in the test, firstly, a spiral stirrup (steel bar) is added into a test piece template and is axially placed along the round hole, and then FRP (fiber reinforced Plastic) reinforcements which are 700mm long and 8mm in diameter and listed in a table 4 are penetrated through the symmetrical round holes of the template 1) to enable the length of the FRP reinforcements to be positioned in the spiral stirrup;
3) mixing and preparing concrete according to the types and the mixing proportion of the raw materials listed in the table 4, wherein the slag sulphoaluminate cement is prepared by mixing and grinding 60-90% of granulated blast furnace slag, 10-30% of anhydrite and 5-10% of high belite sulphoaluminate cement clinker in percentage by weight;
4) pouring and compacting the concrete mixed in the step 3) in the template provided with the spiral stirrup and the FRP rib obtained in the step 2);
5) and 4) curing and stripping the poured and compacted concrete according to a conventional method to obtain the concrete member of the embodiment 10-19 with the structure shown in figure 1.
TABLE 4 compositions of FRP rib-kieselguhr concrete members of examples 10 to 19
Reinforced-silicate cement concrete members of comparative examples 4 to 11 were prepared according to the mixing ratios listed in table 5 below with reference to the member casting methods of examples 10 to 19.
TABLE 5 composition of Reinforcement-Portland Cement concrete Member of comparative examples 4 to 11
The concrete test pieces of the above embodiments 10 to 19 and comparative examples 4 to 11 have the structure shown in fig. 1, and are formed by combining a concrete cube 1 and a single reinforcement 2, wherein the single reinforcement 2 penetrates through the concrete cube 1, a short loading end 21 is formed on one side of the concrete cube 1, a long free end 22 is formed on the other side of the concrete cube 1, and a stirrup 11 is further provided inside the concrete cube 1 to prevent the test piece from cracking. The test pieces with the structure are respectively marked as test groups 10-19 and comparison groups 4-11, and the following drawing tests are carried out:
(1) respectively arranging displacement meters at the free end 22 and the loading end 21 of the test piece rib material;
(2) a 600kN hydraulic servo universal testing machine is used as a loading device, drawing acting force is applied to a loading end 21 of the test piece rib material, and the loading speed is 0.75 mm/min; measuring the slippage of the free end 22 and the loading end 21 of the bar material by a displacement meter and a dynamic data acquisition instrument, and simultaneously measuring the drawing force by a force sensor; when the reinforcement is pulled out or broken, the concrete is split or the slip quantity of the free end 22 exceeds 20mm, the loading is stopped when the load is increased and the load floats very little;
(3) calculating the bonding strength tau (MPa) between the reinforcement and the concrete according to the following formula (I):
wherein d represents a tendon diameter (mm), P represents a drawing force (N), ldAnd represents the length (mm) of the bonding section of the reinforcement and the concrete.
The bonding strength between the ribs and the matrix in each of the members cured at 1d and 28d and immersed in seawater at 40 ℃ for 15d, 30d, 45d, 60d, 90d, 180d, 360d and 720d was measured according to the above-mentioned drawing test. The seawater soaking method is to corrode the concrete beam in a simulation test pool by adopting a corrosion method of dry-wet circulation and soaking of a 5% sodium chloride solution.
The test results are shown in Table 6.
TABLE 6 Performance test results of the test groups 10-19 and the control groups 4-11
As can be seen from table 6 above, the FRP bar-agalmatolite concrete member of the present invention achieves a significant improvement in seawater soaking resistance by selecting a suitable combination of concrete and FRP bars. The components of each test group can still keep good bonding strength between the ribs and the matrix after being soaked in seawater at 40 ℃ for a long time, the strength retention rate of each test group test piece after being soaked for 720 days is higher than 105%, and the strength retention rate of the test piece after being soaked for 720 days is less than 95% and generally less than 85% no matter the ordinary portland cement concrete is matched with the reinforcing steel bars or the basalt fiber reinforced plastic ribs.
The FRP rib-ettringite concrete beam members of examples 20 to 29 were prepared by casting in accordance with the formulation shown in Table 4. The method comprises the following specific steps:
1) setting a template according to the specifications of 1500mm of total length, 200mm of total width and 100mm of total height of the test piece;
2) taking the FRP ribs listed in the table 4 as main ribs, and longitudinally arranging 2 FRP ribs at two side positions in the template arranged in the step 1); within the range of main reinforcements, 434mm in the middle is a pure bending section, 433mm on both sides is a sheared area, stirrups are arranged at the sheared areas of the left end and the right end of the beam test piece at intervals of 80-120mm respectively, and no stirrup is arranged in the pure bending section;
3) mixing and preparing concrete according to the types and the mixing proportion of the raw materials listed in the table 4, wherein the slag sulphoaluminate cement is prepared by mixing and grinding 60-90% of granulated blast furnace slag, 10-30% of anhydrite and 5-10% of high belite sulphoaluminate cement clinker in percentage by weight;
4) pouring and compacting the concrete mixed in the step 3) in the template provided with the stirrups and the FRP ribs obtained in the step 2);
5) and 4) curing and stripping the poured and compacted concrete according to a conventional method to obtain the concrete beam member of the embodiment 20-29 with the structure as shown in figure 2.
Reinforced-portland cement concrete beam members were prepared as comparative examples 12 to 17 according to the mixing ratios listed in table 7 below with reference to the casting methods of the members of examples 20 to 29.
TABLE 7 compositions of reinforced Portland Cement concretes of comparative examples 12 to 17
The following bending resistance tests were conducted using the beam members of examples 20 to 29 as test groups 20 to 29 and the beam members of comparative examples 12 to 17 as control groups 12 to 17, respectively:
the four-point bending loading of the concrete beam shown in the figure 2 is carried out by adopting an MTS actuator with the measuring range of 300kN, the loading speed before all the concrete beams of the test piece are cracked is 0.3mm/min, the loading speed after the steel bar beam with the yield point is cracked is 1.0mm/min, the crack width is measured every 5kN, and the test is stopped when other damage forms such as concrete crushing, main reinforcement breaking or shearing damage and the like occur in the compression area of the concrete beam of the test piece.
The bending resistance of the concrete beam is measured according to the 4-point bending resistance test, and the bending strength and the deflection of the beam member which is cured for 28d and soaked in seawater at 40 ℃ for 6 months, 9 months, 12 months and 24 months are measured and are respectively marked as test groups 20-29 and control groups 12-17. The seawater soaking method is to corrode the concrete beam in a simulation test pool by adopting a corrosion method of 5% sodium chloride solution dry-wet circulation and soaking.
The results of the tests are shown in Table 8.
TABLE 8 concrete Beam 4-Point bending test results
Note: the flexural strength retention ratios described in table 8 are ratios to the initial strength.
As can be seen from the above Table 8, the beam member combination of FRP tendon-calcium alum stone concrete of the invention has obviously improved bending resistance compared with the traditional steel bar-portland cement concrete member and FRP tendon-portland cement concrete member. The bending strength and the corresponding deflection value of the beam member of the FRP rib-ettringite concrete are higher than those of the FRP rib-portland cement concrete with the same proportion. The FRP rib-calcium alum stone concrete has excellent seawater corrosion resistance, and the flexural strength retention rate of the member is over 100 percent after the FRP rib-calcium alum stone concrete is soaked in seawater at 40 ℃ for 24 months, which shows that the flexural strength of the member is not reduced but slightly improved; the strength retention rate of the corresponding steel bar-portland cement concrete is reduced to below 90%, and the bending strength retention rate of the FRP bar-portland cement concrete is even reduced to below 60%.
Claims (15)
1. An ettringite cement concrete, its raw materials composition is by weight percent, it is made up of ettringite cement 10% -20%, fine aggregate 25% -40%, coarse aggregate 40% -55%, water 4% -10% and admixture 0.05% -0.2%; the ettringite cement is slag sulphoaluminate cement; the fine aggregate is a mixture of river sand and sea sand, and the weight of the sea sand in the mixture accounts for 25-50%; the slag sulphoaluminate cement is prepared by mixing and grinding 60-90% of granulated blast furnace slag, 10-30% of anhydrite and 5-10% of high belite sulphoaluminate cement clinker in percentage by weight.
2. The ettringite cement concrete according to claim 1, characterized in that: the raw material components comprise 14-19% of ettringite cement, 27-36% of fine aggregate, 43-52% of coarse aggregate, 6-7.5% of water and 0.1-0.2% of additive.
3. The ettringite cement concrete according to claim 1, characterized in that: the water-to-gel ratio of the raw material components is 0.3-0.5.
4. The ettringite cement concrete according to claim 3, characterized in that: the water-gel ratio of the raw material components is 0.3-0.45.
5. The ettringite cement concrete according to claim 3, characterized in that: the water-gel ratio of the raw material components is 0.33.
6. The ettringite cement concrete according to claim 1, characterized in that: the fine aggregate is a mixture of river sand and sea sand, and the weight of the sea sand in the mixture accounts for 50%.
7. A concrete member resistant to seawater and high salt environment erosion which is cast from raw materials comprising FRP ribs and the ettringite cement concrete of claim 1.
8. The concrete structure of claim 7 wherein: in the raw materials, the FRP rib accounts for 2 to 5 percent by volume percent, and the ettringite cement concrete as claimed in claim 1 accounts for 95 to 98 percent by volume percent.
9. The concrete structure of claim 7 wherein: in the raw materials, the FRP rib accounts for 2 to 3 percent by volume percent, and the ettringite cement concrete of claim 1 accounts for 97 to 98 percent by volume percent; and the water-to-gel ratio of the ettringite cement concrete is 0.4-0.5.
10. The concrete structure of claim 9 wherein: the water-to-gel ratio of the ettringite cement concrete is 0.45.
11. The concrete structure of claim 7 wherein: the FRP ribs are selected from any one or the combination of more than two of basalt fiber reinforced plastic ribs, glass fiber reinforced plastic ribs, carbon fiber reinforced plastic ribs and aramid fiber reinforced plastic ribs.
12. The concrete structure of claim 11 wherein: the FRP ribs are selected from glass fiber reinforced plastic ribs or basalt fiber reinforced plastic ribs.
13. The concrete structure of claim 11 wherein: the FRP ribs are basalt fiber reinforced plastic ribs.
14. The concrete structure of claim 7 wherein: the concrete is poured by the following raw materials by volume percentage: 2 to 3 percent of basalt fiber reinforced plastic rib and 97 to 98 percent of ettringite cement concrete; the ettringite cement concrete consists of 14 to 19 percent of ettringite cement, 27 to 36 percent of fine aggregate, 43 to 52 percent of coarse aggregate, 6 to 7.5 percent of water and 0.1 to 0.2 percent of additive, and the water-to-gel ratio is 0.45; the fine aggregate is a mixture of sea sand and river sand, and the weight percentage of the sea sand is 50%.
15. The concrete structure of claim 7 wherein: the concrete is poured by the following raw materials by volume percentage: 2 to 3 percent of FRP rib and 97 to 98 percent of ettringite cement concrete; the FRP ribs are glass fiber reinforced plastic ribs; the ettringite cement concrete consists of 14 to 19 percent of slag sulphoaluminate cement, 27 to 36 percent of fine aggregate, 43 to 52 percent of coarse aggregate, 6 to 7.5 percent of water and 0.1 to 0.2 percent of additive, and the water-to-glue ratio is 0.45; the fine aggregate is a mixture of sea sand and river sand, and the weight percentage of the sea sand is 25-50%.
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| CN202010458660.XA CN111574167B (en) | 2020-05-27 | 2020-05-27 | Seawater corrosion resistant concrete member and preparation method thereof |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103626457A (en) * | 2013-12-16 | 2014-03-12 | 北京航空航天大学 | Corrosion-resistant concrete for salty environment, and manufacturing method and construction technique thereof |
| CN103938803A (en) * | 2014-04-04 | 2014-07-23 | 浙江大学 | High toughness cement-based material-nonmetal fiber rib composite structure as well as application and application method thereof |
| CN107117912A (en) * | 2017-05-08 | 2017-09-01 | 北京工业大学 | Fiber concrete, preparation and application that a kind of airfield pavement is quickly repaired |
| CN108546060A (en) * | 2018-06-28 | 2018-09-18 | 北京工业大学 | A kind of repairing high belite sulphoaluminate cement base anti-disturbance concrete and preparation method thereof |
| CN109824329A (en) * | 2019-03-06 | 2019-05-31 | 唐山北极熊建材有限公司 | Self-compaction leveling concrete and its preparation method and application |
-
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103626457A (en) * | 2013-12-16 | 2014-03-12 | 北京航空航天大学 | Corrosion-resistant concrete for salty environment, and manufacturing method and construction technique thereof |
| CN103938803A (en) * | 2014-04-04 | 2014-07-23 | 浙江大学 | High toughness cement-based material-nonmetal fiber rib composite structure as well as application and application method thereof |
| CN107117912A (en) * | 2017-05-08 | 2017-09-01 | 北京工业大学 | Fiber concrete, preparation and application that a kind of airfield pavement is quickly repaired |
| CN108546060A (en) * | 2018-06-28 | 2018-09-18 | 北京工业大学 | A kind of repairing high belite sulphoaluminate cement base anti-disturbance concrete and preparation method thereof |
| CN109824329A (en) * | 2019-03-06 | 2019-05-31 | 唐山北极熊建材有限公司 | Self-compaction leveling concrete and its preparation method and application |
Non-Patent Citations (1)
| Title |
|---|
| 不同辅助胶凝材料对快速施工用海洋硫铝酸盐水泥性能的影响及机理研究;肖忠明等;《水泥》;20180930;第1-8页 * |
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