CN114057456A - Multi-scale reinforced light high-ductility cement-based composite material and preparation method thereof - Google Patents
Multi-scale reinforced light high-ductility cement-based composite material and preparation method thereof Download PDFInfo
- Publication number
- CN114057456A CN114057456A CN202111590723.8A CN202111590723A CN114057456A CN 114057456 A CN114057456 A CN 114057456A CN 202111590723 A CN202111590723 A CN 202111590723A CN 114057456 A CN114057456 A CN 114057456A
- Authority
- CN
- China
- Prior art keywords
- parts
- lhdcc
- scale
- reinforcing material
- composite material
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000002131 composite material Substances 0.000 title claims abstract description 59
- 239000004568 cement Substances 0.000 title claims abstract description 44
- 238000002360 preparation method Methods 0.000 title claims description 13
- 239000000463 material Substances 0.000 claims abstract description 103
- 239000000203 mixture Substances 0.000 claims abstract description 46
- 239000012779 reinforcing material Substances 0.000 claims abstract description 46
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 45
- 238000006116 polymerization reaction Methods 0.000 claims abstract description 21
- 230000002787 reinforcement Effects 0.000 claims abstract description 19
- 239000000945 filler Substances 0.000 claims abstract description 17
- 229910052500 inorganic mineral Inorganic materials 0.000 claims abstract description 12
- 239000011707 mineral Substances 0.000 claims abstract description 12
- 239000000835 fiber Substances 0.000 claims description 35
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 claims description 30
- 238000002156 mixing Methods 0.000 claims description 24
- 238000003756 stirring Methods 0.000 claims description 24
- -1 polyethylene Polymers 0.000 claims description 23
- 229910000831 Steel Inorganic materials 0.000 claims description 22
- 239000010959 steel Substances 0.000 claims description 22
- 239000010881 fly ash Substances 0.000 claims description 18
- 239000003638 chemical reducing agent Substances 0.000 claims description 17
- 239000004698 Polyethylene Substances 0.000 claims description 16
- 239000011344 liquid material Substances 0.000 claims description 16
- 229920000573 polyethylene Polymers 0.000 claims description 16
- 239000002002 slurry Substances 0.000 claims description 16
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 15
- 229910000019 calcium carbonate Inorganic materials 0.000 claims description 15
- 239000002245 particle Substances 0.000 claims description 14
- 229920000876 geopolymer Polymers 0.000 claims description 10
- 239000004005 microsphere Substances 0.000 claims description 10
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 claims description 8
- 238000009210 therapy by ultrasound Methods 0.000 claims description 8
- 238000005303 weighing Methods 0.000 claims description 8
- 229920002577 polybenzoxazole Polymers 0.000 claims description 7
- 229910021487 silica fume Inorganic materials 0.000 claims description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 4
- 229920006231 aramid fiber Polymers 0.000 claims description 4
- 239000000378 calcium silicate Substances 0.000 claims description 4
- 229910052918 calcium silicate Inorganic materials 0.000 claims description 4
- OYACROKNLOSFPA-UHFFFAOYSA-N calcium;dioxido(oxo)silane Chemical compound [Ca+2].[O-][Si]([O-])=O OYACROKNLOSFPA-UHFFFAOYSA-N 0.000 claims description 4
- 239000011521 glass Substances 0.000 claims description 4
- 239000010451 perlite Substances 0.000 claims description 4
- 235000019362 perlite Nutrition 0.000 claims description 4
- 239000000843 powder Substances 0.000 claims description 4
- 150000004645 aluminates Chemical class 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims description 3
- 239000002893 slag Substances 0.000 claims description 3
- 239000010455 vermiculite Substances 0.000 claims description 3
- 229910052902 vermiculite Inorganic materials 0.000 claims description 3
- 235000019354 vermiculite Nutrition 0.000 claims description 3
- 229920002430 Fibre-reinforced plastic Polymers 0.000 claims description 2
- 239000000654 additive Substances 0.000 claims description 2
- 230000000996 additive effect Effects 0.000 claims description 2
- 239000011248 coating agent Substances 0.000 claims description 2
- 238000000576 coating method Methods 0.000 claims description 2
- 239000011151 fibre-reinforced plastic Substances 0.000 claims description 2
- 229910052742 iron Inorganic materials 0.000 claims description 2
- 239000003469 silicate cement Substances 0.000 claims description 2
- 238000007667 floating Methods 0.000 abstract description 4
- 230000000052 comparative effect Effects 0.000 description 42
- 239000011159 matrix material Substances 0.000 description 37
- 229920000642 polymer Polymers 0.000 description 30
- 239000010410 layer Substances 0.000 description 16
- 238000005336 cracking Methods 0.000 description 8
- 239000005543 nano-size silicon particle Substances 0.000 description 8
- 230000003014 reinforcing effect Effects 0.000 description 8
- 229910052814 silicon oxide Inorganic materials 0.000 description 8
- 239000004743 Polypropylene Substances 0.000 description 7
- 229920003023 plastic Polymers 0.000 description 7
- 239000004033 plastic Substances 0.000 description 7
- 229920001155 polypropylene Polymers 0.000 description 7
- 230000008439 repair process Effects 0.000 description 7
- IUVCFHHAEHNCFT-INIZCTEOSA-N 2-[(1s)-1-[4-amino-3-(3-fluoro-4-propan-2-yloxyphenyl)pyrazolo[3,4-d]pyrimidin-1-yl]ethyl]-6-fluoro-3-(3-fluorophenyl)chromen-4-one Chemical compound C1=C(F)C(OC(C)C)=CC=C1C(C1=C(N)N=CN=C11)=NN1[C@@H](C)C1=C(C=2C=C(F)C=CC=2)C(=O)C2=CC(F)=CC=C2O1 IUVCFHHAEHNCFT-INIZCTEOSA-N 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 4
- 230000008859 change Effects 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 239000003822 epoxy resin Substances 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 239000003921 oil Substances 0.000 description 3
- 229920000647 polyepoxide Polymers 0.000 description 3
- 239000000377 silicon dioxide Substances 0.000 description 3
- 238000005482 strain hardening Methods 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 2
- UFWIBTONFRDIAS-UHFFFAOYSA-N Naphthalene Chemical compound C1=CC=CC2=CC=CC=C21 UFWIBTONFRDIAS-UHFFFAOYSA-N 0.000 description 2
- 239000004760 aramid Substances 0.000 description 2
- 239000011324 bead Substances 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 239000004567 concrete Substances 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 230000002708 enhancing effect Effects 0.000 description 2
- 230000036571 hydration Effects 0.000 description 2
- 238000006703 hydration reaction Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 230000002401 inhibitory effect Effects 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- 230000002195 synergetic effect Effects 0.000 description 2
- 238000009864 tensile test Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 229910001018 Cast iron Inorganic materials 0.000 description 1
- 239000011398 Portland cement Substances 0.000 description 1
- 230000006750 UV protection Effects 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 125000001931 aliphatic group Chemical group 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000004566 building material Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000011325 microbead Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002086 nanomaterial Substances 0.000 description 1
- RECVMTHOQWMYFX-UHFFFAOYSA-N oxygen(1+) dihydride Chemical compound [OH2+] RECVMTHOQWMYFX-UHFFFAOYSA-N 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 230000021715 photosynthesis, light harvesting Effects 0.000 description 1
- 230000002028 premature Effects 0.000 description 1
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 1
- 230000004224 protection Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000012783 reinforcing fiber Substances 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 229920002994 synthetic fiber Polymers 0.000 description 1
- 239000012209 synthetic fiber Substances 0.000 description 1
- 239000002562 thickening agent Substances 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
- 230000003245 working effect Effects 0.000 description 1
Images
Classifications
-
- 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
-
- 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
- C04B14/00—Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B14/38—Fibrous materials; Whiskers
- C04B14/383—Whiskers
-
- 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
- C04B14/00—Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B14/38—Fibrous materials; Whiskers
- C04B14/46—Rock wool ; Ceramic or silicate fibres
- C04B14/4643—Silicates other than zircon
-
- 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
- C04B20/00—Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials
- C04B20/0076—Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials characterised by the grain distribution
-
- 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
- C04B20/00—Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials
- C04B20/0076—Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials characterised by the grain distribution
- C04B20/008—Micro- or nanosized fillers, e.g. micronised fillers with particle size smaller than that of the hydraulic binder
-
- 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
-
- 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
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A30/00—Adapting or protecting infrastructure or their operation
- Y02A30/30—Adapting or protecting infrastructure or their operation in transportation, e.g. on roads, waterways or railways
Abstract
The invention relates to a light high-ductility cement-based composite material, which improves the strength, ductility and stability by carrying out multi-scale reinforcement on nano, micron, millimeter and other scales. The composite material comprises a mixture comprising: 870 parts of a cementing material 490-containing material, 392 parts of a mineral admixture 220-containing material, 330 parts of a light filler 195-containing material, 20-40 parts of a nanoscale reinforcing material, 15-30 parts of a micron-scale reinforcing material, 15-20 parts of a millimeter-scale reinforcing material, 240 parts of water 213-containing material and 75-85 parts of an admixture. Further, the mixture is poured into a die cavity with multiple layers of polymerization grids arranged in parallel, so that the LHDCC mixture is embedded into holes and gaps of the polymerization grids of each layer, the polymerization grids are wrapped, and after the LHDCC is hardened, a stress whole of the polymerization grids/the LHDCC is formed, thereby realizing the macro-scale reinforcement of the LHDCC. The material breaks through the problems of low strength, poor ductility, poor stability and the like of the conventional LHDCC, and has wide application prospect in extremely severe environment infrastructures such as high-rise buildings, large-span structures, offshore floating platforms, oil and gas pipelines and the like.
Description
Technical Field
The invention relates to a Lightweight high-ductility cement-based composite material (LHDCC) and a preparation method thereof, belonging to the technical field of building materials.
Background
High-ductility cement-based composites (HDCC) are an improved class of high-performance fiber-reinforced cement-based composites. It is characterized by tensile strain hardening and multi-crack cracking behavior, and allows a plurality of cracks of fine pitch to be uniformly formed at other positions of a sample as the load increases after the matrix is primarily cracked in the HDCC, and the opening width of each crack is limited to a small value (less than 100 μm), which makes the transmission rate of water and chloride ions small, so that the HDCC exhibits good durability. In addition, HDCC shows the strain hardening performance similar to metal due to the multi-crack cracking behavior, and has the tensile strain capacity of more than 3 percent which is 300 times that of the traditional concrete. Because of good ductility, excellent crack control capability, high toughness, impermeability, durability and the like, the composite material is widely applied to projects such as repair and reinforcement, special building protection, earthquake-resistant energy dissipation structures and the like.
LHDCC is a composite material with low density and low heat conductivity coefficient developed by introducing light filler or bubbles on the basis of HDCC. Due to the low specific gravity, the composite material has wide application prospect in high-rise building structures, large-span structures and ocean floating structures. Particularly when used as a repair reinforcement material, is advantageous because it does not place excessive additional loads on the structure being repaired and reinforced. In addition, LHDCC is of great significance to structures having thermal insulation due to its low thermal conductivity, and, for example, there have been attempts to apply LHDCC to a pipe-in-pipe packing material to satisfy the thermal insulation and mechanical property requirements of oil or gas pipelines in deep and ultra-deep water regions.
Although LHDCC has been developed for a long time, its use has been limited due to a great reduction in strength and ductility compared to conventional HDCC. Publication No. CN 109761564A discloses a HDCC which is made of 442 parts of 334-152 cement, 223-552 parts of fly ash, 76-78 parts of silica fume, 8.5-8.6 parts of expanded perlite, 127-129 parts of floating beads, 19.3-1.17 parts of thickening agent, 7.1-11.9 parts of glass fiber, 0.1-234 parts of mineral powder and 0.1-20 parts of early strength agent, and the obtained material has volume weight not exceeding 1400kg/m3 and breaking strength higher than 5MPa, but the material of the invention has low strength and does not give the most main tensile property of the high-ductility cement composite material. The publication No. CN112694342A discloses HDCC and a preparation method thereof, the material comprises, by weight, 700 parts of 600-ion cement, 300 parts of 200-ion glass beads, 200 parts of 100-ion silica fume, 350 parts of 250-ion yellow sand, 20-40 parts of light sand, 30-40 parts of high efficiency water reducing agent, 20-30 parts of synthetic fiber and 270 parts of 230-ion water, and the obtained material is simpler than the raw material of the material disclosed by the publication No. CN 109761564A, and has the volume weight of 1436-ion silica fume 1643kg/m3, the tensile strength of 4.1-4.9MPa and the tensile strain capacity of 4.0-4.6%, but the tensile capacity of the material can not meet the engineering requirements.
In practical engineering, especially under extreme conditions (such as earthquakes), the strength and ductility of structural materials are both of high concern in structural design in order to ensure the safety of the infrastructure under extreme loads. There is a need to increase the ductility of a structure to ensure that the structure can absorb the powerful energy generated in a major event such as an earthquake, so that the possibility of building collapse and the need for frequent repairs are greatly reduced. Building earthquake-resistant design specifications, such as EN 1998-1:2004, require that the tensile strain capacity of the steel bars be greater than 9%. The national specification (GB 50011-2010) requires that the peak strain of the anti-seismic steel bar is not less than 9% and the elongation of the steel bar is not less than 20%. At present, most existing cement-based materials (including HDCC and LHDCC with high ductility) do not achieve such high levels of tensile strain. In recent years, new thin-walled HDCC/profile steel composite beams, steel-HDCC-steel sandwich composite plates and shells, and steel-HDCC-steel sandwich pipe-in-pipe structures have been developed. It is clear that when such structures are subjected to extreme loads, the steel may maintain its contribution, but the cement matrix may fail in tension. Therefore, it is necessary to develop LHDCC having higher strength and/or ductility.
Disclosure of Invention
Based on the problems, the invention provides a method for enhancing LHDCC in a multi-scale manner by adopting nano materials to regulate and control hydration products and adopting whiskers, fibers and a polymer grid, so that the probability of premature failure of the LHDCC due to insufficient bridging force is reduced, and the LHDCC with light weight, high strength and high elongation is obtained.
In order to achieve the purpose, the technical scheme provided by the invention is as follows:
a lightweight high ductility cement-based composite (LHDCC) based on multiscale reinforcement, comprising a mixture comprising: 870 parts of a cementing material 490-containing material, 392 parts of a mineral admixture 220-containing material, 330 parts of a light filler 195-containing material, 20-40 parts of a nanoscale reinforcing material, 15-30 parts of a micron-scale reinforcing material, 15-20 parts of a millimeter-scale reinforcing material, 240 parts of water 213-containing material and 75-85 parts of an admixture.
Wherein, the gel material, the mineral admixture and the light filler form a matrix material of LHDCC, and the multi-scale reinforcing material is uniformly doped in the matrix material. The nanoscale reinforcing material in the multi-scale reinforcing material has a nanoscale size, the microscale reinforcing material has a microscale size, and the millimeter-scale reinforcing material has a millimeter-scale size.
Preferably, the composite material also comprises a plurality of polymeric meshes, and the mixture wraps the polymeric meshes to form a polymeric mesh/LHDCC stressed whole body so as to realize macro-scale reinforcement.
Preferably, the cementing material is one or more of silicate cement, aluminate cement and sulphoaluminate cement;
preferably, the mineral admixture is one or more of slag powder, fly ash and silica fume;
preferably, the light filler is one or more of fly ash hollow microspheres, glass hollow microspheres, expanded perlite and expanded vermiculite, and the particle size range is 10-300 μm.
Preferably, the nanoscale reinforcing material comprises one or more of nano silicon oxide particles, nano calcium silicate particles and nano calcium carbonate particles, and the average particle size of the particles is less than or equal to 40 nm.
Preferably, the micron-scale reinforcing material comprises one or more of calcium carbonate whiskers and calcium sulfate whiskers, the diameter of the micron-scale reinforcing material is 100-200nm, and the length of the micron-scale reinforcing material is 50-80 μm.
Preferably, the millimeter-scale reinforcing material comprises one or more of polyethylene fibers, aramid fibers and Polybenzobisoxazole (PBO) fibers, the diameter of the fibers is 12-50 mu m, and the length of the fibers is greater than or equal to 12 mm.
Preferably, the admixture comprises a water reducing agent with a water reducing rate of more than or equal to 30%.
Preferably, the polymeric mesh comprises one or more combinations of fiber reinforced polymer mesh, geopolymer mesh, iron wire mesh, steel strand mesh.
Preferably, the space between the polymerization grid lines is 10-40mm, and the grid thickness is 0.8-5 mm; the number of the layers of the polymerization grid arrangement is 0-3, and the distance between every two layers is 4-6 mm; the mixture forms a coating on the polymeric mesh having a thickness greater than 4 mm.
The invention also provides a preparation method of any one of the light weight high ductility cement-based composite materials (LHDCC), which comprises the following steps:
(1) weighing a cementing material, a mineral admixture, a light filler, a nanoscale reinforcing material, a microscale reinforcing material, a millimeter-scale reinforcing material, water and an admixture in parts by weight;
(2) uniformly mixing and stirring the gelled material, the mineral admixture and the light filler to obtain a dry material;
(3) fully mixing water, an additive, a nanoscale reinforcing material and a microscale reinforcing material to obtain a liquid material;
(4) adding the liquid material into the dry material, and uniformly mixing and stirring to obtain slurry;
(5) adding a millimeter-scale reinforcing material into the slurry, and uniformly stirring to obtain a fresh mixture;
(6) and then pouring the newly-mixed mixture into a die cavity with a plurality of layers of polymerization grids arranged in parallel at intervals, embedding the newly-mixed mixture into holes and gaps of each layer of polymerization grids, wrapping the polymerization grids, and hardening the mixture to form a polymerization grid/LHDCC stressed whole.
Preferably, in the step (3), the water, the admixture, the nano-scale reinforcing material and the micro-scale reinforcing material are fully mixed, and the ultrasonic treatment is carried out for 15min in an ultrasonic instrument with the power of 80W.
The invention has the following beneficial effects:
(1) compared with the LHDCC which is not subjected to multi-scale reinforcement and has the same base material, the multi-scale reinforced LHDCC composite material prepared by adopting the multi-scale reinforcing method has obviously improved tensile strength.
(2) The tensile strain capacity of the multi-scale reinforced LHDCC composite material prepared by the invention can be regulated and controlled by nano-micron-millimeter scale synergistic reinforcement, and can reach more than 9 percent, namely the tensile strain capacity level of a steel bar in an earthquake-resistant building body is 3 times of that of the conventional LHDCC, and is improved by more than one time compared with a single-scale reinforcing scheme in the prior art;
(3) the multi-scale reinforced LHDCC composite material can select whether to add the polymeric grid or not and which polymeric grid to add according to the needs, thereby obtaining diversified LHDCC integral structures with different ductility and strength;
(4) the multi-scale reinforced LHDCC composite material prepared by the invention has the advantages of low content of 1310-3The volume weight of the composite material is 20-40% lower than that of the traditional HDCC, the lightweight characteristic of LHDCC is kept, and the lightweight characteristic is not lost due to strength improvement.
(5) By means of a multi-scale reinforcing means, while the light weight characteristics of LHDCC are kept, the mechanical properties including the strength, the ductility and the like of the strain capacity are remarkably improved, the application field of the LHDCC is greatly expanded, and the LHDCC can be alternatively applied to a building main body which has strict requirements on the strength, the ductility and the like of a structural material, for example, the tensile strain capacity of a steel bar is required to be more than 9 percent by building earthquake-resistant design specifications, but the tensile strain of most of the existing cement-based materials cannot reach such a high level, so that the steel bar cannot be fully utilized, the material provided by the invention has the strain capacity of 9 percent, and the performance of the steel bar can be fully exerted when the material is used in engineering. In addition, the novel thin-wall HDCC/section steel composite beam, steel-HDCC-steel sandwich composite plate and shell and steel-HDCC-steel sandwich pipe-in-pipe structure newly developed in recent years can fully exert the performance of steel on one hand, lighten the self weight of the structure and expand the application field of the material, for example, the novel thin-wall HDCC/section steel composite beam, the steel-HDCC-steel sandwich composite plate and shell and the steel-HDCC-steel sandwich pipe-in-pipe structure.
(6) The LHDCC can repair and reinforce the existing structure, for example, the material added with the basalt polymer mesh has high tensile strength while keeping enough ductility, and can be used for repairing and reinforcing the structure which is sensitive to self weight, such as high-rise, large-span and ancient buildings. The structure performance is improved, and meanwhile, the obvious self-weight change of the lower structure is avoided. This is particularly important for structures that are relatively dead weight sensitive.
(7) The LHDCC of the invention has stronger crack control capability simultaneously, can realize fine multi-crack cracking in the process of tensile stress, and the width of the crack can be controlled within 100 microns, so that the water or chloride ion permeation rate of the material is smaller, therefore, the material has good durability, has wider application without being limited to being used as the material of a building main body, for example, a composite material added with a basalt polymer grid or a geopolymer grid has 1.8 to 7 percent of strain and 10.6 to 18MPa of tensile strength, is suitable for sewage well covers, pipeline well covers and the like, solves the problems of poor durability, theft, poor impact resistance, low toughness and the like of the well covers, and can also be used for manufacturing oil and gas conveying pipelines.
Drawings
FIG. 1 is a graph of the tensile stress strain curves of LHDCC of comparative examples A1-A4 and examples A1-A5;
figure 2 is a tensile stress strain plot of LHDCC of comparative example B1 and examples B1-B2.
Detailed Description
The invention is further illustrated by the following examples, which are not intended to be limiting.
The inventors of the present application found, in a great deal of experiments and practice, that the strength of LHDCC is reduced mainly due to the fact that the introduced lightweight filler is a loose porous structure itself, which exists as a weak term in the matrix of LHDCC; in addition, the introduction of air bubbles or light weight fillers can also increase the porosity within the ECC matrix. These weaknesses and voids, when present at the interface between the fiber matrix, can impair the interfacial bonding properties of the fiber matrix, thereby affecting the fiber bridging properties. The tensile properties of HDCC are dependent on the fiber bridging properties, and the lack of bridging properties is the main cause of the decrease in LHDCC tensile strength and ductility.
According to the invention, a multi-scale reinforced modified material is added, one or more of nano silicon oxide, nano calcium carbonate and nano calcium silicate particles are used for regulating and controlling hydration products of LHDCC on a nano scale, one or more of calcium carbonate whisker and calcium sulfate crystal form is used for inhibiting defects and cracks of LHDCC on a micron scale, one or more of polyethylene fiber, aramid fiber and Polybenzobisoxazole (PBO) fiber is used for inhibiting and controlling crack propagation of LHDCC on a millimeter scale, and the microstructure and fiber bridging performance of the matrix of LHDCC can be improved, so that the mechanical property of the matrix material of LHDCC is improved.
Further, by placing a continuous polymeric lattice in the modified LHDCC matrix material, the overall mechanical properties of the LHDCC can be further improved by providing additional crack bridging forces. The principle is that LHDCC matrix mixture is poured into a plurality of layers of polymerization grid holes and gaps which are arranged in parallel, the polymerization grid is wrapped, the polymerization grid/LHDCC stress whole is formed after cement is hardened, the polymerization grid and the LHDCC matrix material bear load together at the initial stress stage, a first crack appears when the cement matrix reaches the bearing limit, the polymerization grid and fibers in the LHDCC play a bridging role to resist the expansion of the crack together, and then the crack is formed at other positions of the composite material, so that multi-crack cracking is formed in the composite material repeatedly, and the composite material is endowed with the characteristics of multi-crack cracking and strain hardening. As the polymerization grid provides additional crack bridging force, the tensile strength and the multi-seam cracking stability of the composite material are greatly improved, and the light-weight characteristic is also maintained, so that the composite material is a high-quality reinforcing and repairing material. Different polymer meshes are selected as reinforcing materials according to different engineering requirements, so that LHDCC composite materials with different properties are obtained.
The raw materials used are conventional materials and reagents, all of which are commercially available.
The cementitious material used in the examples was po.52.5 portland cement. Of course, aluminate cements and sulphoaluminate cements may also be used.
The mineral admixture used in the examples was type F first grade fly ash or silica fume. Of course, slag powder may also be used.
The nanoscale modified material used in the examples was nano-silica having an average particle size of 40nm and a SiO2 content of 99.8% or more. Of course, nano calcium carbonate and nano calcium silicate may also be used.
The micron-scale reinforcing material used in the examples is calcium carbonate whisker with the diameter of 100-200nm and the length of 50-80 μm. Calcium sulfate whiskers may of course also be used.
The millimeter-sized reinforcing fibers used in the examples were polyethylene fibers having a diameter of 26 μm, a length of 12 to 50mm and a tensile strength of more than 2900 MPa. Of course, aramid fibers, Polybenzobisoxazole (PBO) may also be used.
The light filler is fly ash hollow micro-bead with particle size of 10-300 μm. Of course, glass cenospheres, expanded perlite, expanded vermiculite may also be used.
The admixture used is a water reducing agent having a water reducing rate of 30% or more, such as a polycarboxylic acid water reducing agent. Of course, naphthalene-based superplasticizers, aliphatic superplasticizers and amino superplasticizers may also be used.
Description of the correlation between examples and comparative examples
Next, comparative example a1, comparative example a2, comparative example A3, comparative example a4 and examples a1, a2, A3, a4, a5 were selected as LHDCC base material a of the same density grade as the prior art (CN 112694342A). Comparative example B1 and examples B1 and B2 below another LHDCC base material B of different density grades than example a1 to example a5 was selected.
It should be noted that, because the ratio of the added light filler is different between the LHDCC matrix material A and the LHDCC matrix material B, the light filler is weak in the composite material, the mechanical property is lower, the performance of the material is worse when the ratio of the light filler is higher, and the difference of the performance data of the finally obtained product is larger. Therefore, the two groups of examples are not comparable, and the two groups of examples should be compared with the corresponding comparative examples respectively to analyze the effect of the multi-scale enhancement technology.
In each comparative example and example:
comparative example a1 without the addition of nano-or micro-scale reinforcement, only fibers, i.e. millimeter-scale reinforcement, were doped as in the prior art (CN 112694342A); comparative example a2 addition of nanoscale reinforcing material to comparative example a 1; comparative example A3 addition of microscale reinforcing materials to comparative example a 1; comparative example a4 a polymeric grid was added over comparative example a 1. The five embodiments are added with nano-scale and micron-scale reinforcing materials at the same time, and the difference between the embodiments is the arrangement mode of the polymeric grid.
Comparative example B1 has no nano-or micro-scale reinforcement added, only fibers, i.e., millimeter-scale reinforcement, doped as in the prior art. Examples B1 and B2 both added nano-, micro-, and millimeter-scale reinforcement materials, with the difference between the polymer lattices being arranged.
For clarity, the contrast of the multi-scale enhancement features of the various comparative examples and embodiments described above is listed in table 1.
TABLE 1 multiscale enhancement feature contrast for comparative examples and examples
The production methods of the respective examples and comparative examples will be specifically described below
Comparative example A1
The LHDCC material comprises the following components in parts by weight: 870 parts of cement, 392 parts of fly ash, 195 parts of cenospheres, 240 parts of water, 85 parts of a water reducing agent and 20 parts of polyethylene fiber.
No aggregate grid is arranged.
LHDCC was prepared according to the following steps:
(1) weighing the materials in parts by weight;
(2) mixing and stirring the cement, the fly ash and the hollow microspheres uniformly to obtain a dry material;
(3) mixing water and a water reducing agent, and carrying out ultrasonic treatment for 15min in an ultrasonic instrument with the power of 80W to obtain a liquid material;
(4) adding the liquid material into the dry material, and uniformly mixing and stirring to obtain slurry;
(5) dispersing and scattering polyethylene fibers into the slurry, and uniformly stirring to obtain a fresh mixture of LHDCC;
(6) and pouring the mixture of the LHDCC into a die cavity, and obtaining the millimeter-scale reinforced LHDCC composite material after the matrix of the LHDCC is hardened.
Comparative example A2
The LHDCC material only enhanced in the nanometer scale and the preparation method thereof are provided, and the LHDCC material comprises the following components in parts by weight: 870 parts of cement, 392 parts of fly ash, 195 parts of cenospheres, 240 parts of water, 85 parts of a water reducing agent, 20 parts of polyethylene fiber and 40 parts of nano silicon oxide.
No aggregate grid is arranged.
LHDCC was prepared according to the following steps:
(1) weighing the materials in parts by weight;
(2) mixing and stirring the cement, the fly ash and the hollow microspheres uniformly to obtain a dry material;
(3) mixing water, a water reducing agent and nano silicon oxide, and carrying out ultrasonic treatment for 15min in an ultrasonic instrument with the power of 80W to obtain a liquid material;
(4) adding the liquid material into the dry material, and uniformly mixing and stirring to obtain slurry;
(5) dispersing and scattering polyethylene fibers into the slurry, and uniformly stirring to obtain a fresh mixture of LHDCC;
(6) and pouring the mixture of the LHDCC into a die cavity, and obtaining the nanoscale reinforced LHDCC composite material after the matrix of the LHDCC is hardened.
Comparative example A3
The LHDCC material only enhanced in micron scale and the preparation method thereof are provided, and the LHDCC material comprises the following components in parts by weight: 870 parts of cement, 392 parts of fly ash, 195 parts of cenospheres, 240 parts of water, 85 parts of a water reducing agent, 20 parts of polyethylene fiber and 30 parts of calcium carbonate whisker.
No aggregate grid is arranged.
LHDCC was prepared according to the following steps:
(1) weighing the materials in parts by weight;
(2) mixing and stirring the cement, the fly ash and the hollow microspheres uniformly to obtain a dry material;
(3) mixing water, a water reducing agent and calcium carbonate whiskers, and carrying out ultrasonic treatment for 15min in an ultrasonic instrument with the power of 80W to obtain a liquid material;
(4) adding the liquid material into the dry material, and uniformly mixing and stirring to obtain slurry;
(5) dispersing and scattering polyethylene fibers into the slurry, and uniformly stirring to obtain a fresh mixture of LHDCC;
(6) and pouring the mixture of the LHDCC into a die cavity, and obtaining the micrometer-scale reinforced LHDCC composite material after the matrix of the LHDCC is hardened.
Comparative example A4
The LHDCC material reinforced only in millimeter scale comprises the following components in parts by weight: 870 parts of cement, 392 parts of fly ash, 195 parts of cenospheres, 240 parts of water, 85 parts of a water reducing agent and 20 parts of polyethylene fiber.
A layer of polypropylene plastic geopolymer grid is arranged, the space between grid lines is 30mm, and the thickness is 2.3 mm.
LHDCC was prepared according to the following steps:
(1) weighing the materials in parts by weight;
(2) mixing and stirring the cement, the fly ash and the hollow microspheres uniformly to obtain a dry material;
(3) mixing water and a water reducing agent, and carrying out ultrasonic treatment for 15min in an ultrasonic instrument with the power of 80W to obtain a liquid material;
(4) adding the liquid material into the dry material, and uniformly mixing and stirring to obtain slurry;
(5) dispersing and scattering polyethylene fibers into the slurry, and uniformly stirring to obtain a fresh mixture of LHDCC;
(6) and pouring the mixture of the LHDCC into a die cavity, and obtaining the polymer grid/LHDCC composite material after the matrix of the LHDCC is hardened.
Example A1
The LHDCC material comprises the following components in parts by weight: 870 parts of cement, 392 parts of fly ash, 195 parts of cenospheres, 240 parts of water, 85 parts of a water reducing agent, 40 parts of nano silicon oxide, 30 parts of calcium carbonate whiskers and 20 parts of polyethylene fibers.
No aggregate grid is arranged.
LHDCC was then prepared according to the following steps:
(1) weighing the materials in parts by weight;
(2) mixing and stirring the cement, the fly ash and the hollow microspheres uniformly to obtain a dry material;
(3) mixing water, a water reducing agent, nano silicon oxide and calcium carbonate crystal whiskers, and carrying out ultrasonic treatment for 15min in an ultrasonic instrument with the power of 80W to obtain a liquid material;
(4) adding the liquid material into the dry material, and uniformly mixing and stirring to obtain slurry;
(5) dispersing and scattering polyethylene fibers into the slurry, and uniformly stirring to obtain a fresh mixture of LHDCC;
(6) and pouring the mixture of the LHDCC into a die cavity, and obtaining the multi-scale reinforced LHDCC composite material after the matrix of the LHDCC is hardened.
Example A2
The material composition of example a2 was the same as example a 1. The basalt polymer composite mesh is characterized in that a layer of basalt polymer mesh is arranged, the distance between mesh lines is 30mm, and the thickness of the mesh is 1 mm.
Correspondingly, the preparation method thereof differs from example 1 in step (6):
and pouring the mixture of the LHDCC which is newly mixed into a die cavity which is provided with the single-layer basalt polymer grid, embedding the mixture of the LHDCC into holes and gaps of the polymer grid, wrapping the polymer grid, and obtaining the multi-scale reinforced LHDCC composite material after the matrix of the LHDCC is hardened.
Example A3
The material composition of example A3 was the same as example a 1. The basalt polymer composite material is characterized in that three layers of basalt polymer grids are arranged, the space between grid lines is 30mm, and the thickness is 1 mm.
Correspondingly, the preparation method differs from example a1 in step (6):
and pouring the mixture of the LHDCC which is newly stirred into a die cavity which is parallelly and alternately provided with three layers of basalt polymer grids, embedding the LHDCC mixture into holes and gaps of the polymer grids, wrapping each layer of polymer grids, and obtaining the multi-scale reinforced LHDCC composite material after the matrix of the LHDCC is hardened.
Example A4
The material composition of example a4 was the same as example a 1. The difference is that a layer of polypropylene plastic geopolymer grid is arranged, the space between grid lines is 30mm, and the thickness is 2.3 mm.
Correspondingly, the preparation method differs from example a1 in step (6):
and pouring the freshly-mixed LHDCC mixture into a die cavity provided with a layer of polypropylene plastic geopolymer grid, embedding the LHDCC mixture into holes and gaps of the polymer grid, wrapping the polymer grid, and hardening the LHDCC matrix to obtain the multi-scale reinforced LHDCC composite material.
Example A5
The material composition of example a5 was the same as example a 1. The difference is that three layers of polypropylene plastic geopolymer grids are arranged, the space between grid lines is 30mm, and the thickness is 2.3 mm.
Correspondingly, the preparation method differs from example a1 in step (6):
and pouring the freshly-mixed LHDCC mixture into a die cavity in which three layers of polypropylene plastic geopolymer grids are arranged in parallel at intervals, embedding the LHDCC mixture into holes and gaps of the polymer grids, wrapping the polymer grids, and hardening the LHDCC matrix to obtain the multi-scale reinforced LHDCC composite material.
Example B1
The LHDCC material comprises the following components in parts by weight: 490 parts of cement, 219 parts of silica fume, 330 parts of cenospheres, 213 parts of water, 86 parts of a water reducing agent, 21.9 parts of nano silicon oxide, 30 parts of calcium carbonate whiskers and 15 parts of polyethylene fibers.
No aggregate grid is arranged.
LHDCC was then prepared according to the following steps:
(1) weighing the materials in parts by weight;
(2) mixing and stirring the cement, the fly ash and the hollow microspheres uniformly to obtain a dry material;
(3) mixing water, a water reducing agent, nano silicon oxide and calcium carbonate crystal whiskers, and carrying out ultrasonic treatment for 15min in an ultrasonic instrument with the power of 80W to obtain a liquid material;
(4) adding the liquid material into the dry material, and uniformly mixing and stirring to obtain slurry;
(5) dispersing and scattering polyethylene fibers into the slurry, and uniformly stirring to obtain a fresh mixture of LHDCC;
(6) and pouring the mixture of the LHDCC into a die cavity, and obtaining the multi-scale reinforced LHDCC composite material after the matrix of the LHDCC is hardened.
Example B2
The material composition of example B2 was the same as example B1. The difference is that two layers of polypropylene plastic geopolymer grids are arranged, the space between grid lines is 30mm, and the thickness is 2.3 mm.
Correspondingly, the preparation method differs from example B1 in step (6):
and pouring the freshly-mixed LHDCC mixture into a die cavity provided with two layers of polypropylene plastic geopolymer grids, embedding the LHDCC mixture into holes and gaps of the polymer grids, wrapping the polymer grids, and hardening the LHDCC matrix to obtain the multi-scale reinforced LHDCC composite material.
Comparative example B1
Comparative example B1 differed from example B1 only in that the material composition did not contain nano-scale reinforcing material nano-silica and micro-scale reinforcing material calcium carbonate whiskers.
Comparison of test results of examples and comparative examples
Tensile test pieces were molded from the LHDCC composites of comparative example A1 to comparative example A4, example A1 to A5, example B1 to B2, and comparative example B1, respectively, and tensile test was conducted after curing for 28 days, and the test results of each comparative example and example are described in comparative detail below.
The tensile stress-strain curves for examples A1-A5 are shown in FIG. 1, and the tensile stress-strain curves for examples B1-B2 are shown in FIG. 2. The tensile strength and tensile ductility of the materials of the examples are shown in Table 2 together with the bulk weight (density) of the materials.
Effect of multiscale enhancement
As can be seen by comparing example a1 with comparative examples a1, a2, and A3, example a1 exhibited 34.6%, 19.1%, and 23.5% increases in tensile strength relative to comparative examples a1, a2, and A3, respectively; the ultimate tensile strain was elevated by 74.9%, 43.75% and 64.3%, respectively. The tensile strength and the ductility are obviously improved. Meanwhile, the volume weight change of the material is very little and is within the experimental error range.
In addition, when compared with the prior art of comparative example 1 and CN112694342A with the same density grade, the tensile strength of example A1 is obviously improved, and the tensile strength is improved by 71.4 percent. The tensile ductility of example A1 was also greatly improved, giving a 130% increase in ultimate tensile strain.
The reason is that by adopting the multi-scale reinforcing technical means, the interface performance of the fiber and the matrix is improved through the nano and micron scale reinforcing material, so that the millimeter scale fiber can better exert the bridging performance to realize the improvement of the material performance.
The tensile strain capacity of the LHDCC composite material prepared in the embodiment A1 even reaches more than 9%, namely the tensile strain capacity level of the steel bar in the earthquake-resistant building body is reached, and the application requirement of constructing the earthquake-resistant building body by matching with the steel bar is completely met.
Therefore, the scheme of the invention maintains the lightweight characteristic and improves the mechanical property of the LHDCC base material, thereby being suitable for more application scenes.
As can be seen by comparing example B1 with comparative example B1, the tensile strength of example B1 is improved by 82.4% relative to comparative example B1; the ultimate tensile strain is improved by 142.8 percent. The tensile strength and the ductility are obviously improved. At the same time, the volume weight change of the material is also very slight.
Therefore, the multi-scale enhancement technical means of the invention is suitable for LHDCC with different densities. Due to the fact that materials with different densities can be adopted according to different requirements in practical engineering, the technical means of the invention can provide the multi-scale reinforced LHDCC material with better mechanical performance at a certain density level.
Effects of the aggregated grid
Examples a2-a5 are based on example a1, and it can be seen from the results of fig. 1 and table 1 that the polymeric grid can further significantly improve the tensile strength based on the multi-scale reinforced LHDCC material of example a 1. Example B2 showed the same trend as compared to example B1.
Meanwhile, it can be seen that the material of the polymer mesh has strong regularity to the ultimate tensile strain, and the ultimate tensile strain of the embodiment a2-a5 has a fallback phenomenon compared with the ultimate tensile strain of the embodiment a1 without the polymer mesh, but still provides a high-strength and light-weight solution for the field, and is suitable for different application scenarios.
Therefore, after the matrix material with excellent mechanical property is obtained by the multi-scale reinforcing technical means, the selection of different polymeric grid materials is combined, and the lightweight and high-strength multi-scale reinforced LHDCC composite material with diversified tensile ductility can be provided for the field.
For example, the basalt polymer mesh adopted in the embodiments a2-A3 is influenced by the characteristics of basalt materials, the tensile ductility is obviously reduced, but the excellent tensile strength still widens the application field for the material, and is suitable for the application field requiring light weight, high strength and low tensile ductility, for example, the method of sticking the polymer mesh and the fiber cloth is often adopted in the repair and reinforcement of high-rise or large-span structures at present, but the used epoxy resin binder has poor ultraviolet resistance, fire resistance and durability, and the material reinforcement or repair structure of the embodiments a2-A3 can replace the existing method, so that the use of epoxy resin and the related problems caused by the epoxy resin are avoided; at present, the well lid in municipal engineering is mainly made of cast iron and fiber concrete, has the defects of great weight, poor volatile toughness and the like, and the materials of the embodiment A2-A3 can meet the requirements of high bending tensile strength, impact resistance, toughness and light weight of the well lid. Related application scenes comprise a plurality of offshore floating structures, oil and gas transmission pipelines, repair and reinforcement of ancient buildings and the like.
As can be seen by comparing example A4 with comparative example A4, example A4 has a 30.9% increase in tensile strength over comparative example A4; the ultimate tensile strain is improved by 17.9 percent. The comparative example A4 which does not adopt multi-scale reinforcement, in the stress process, when the load reaches the cracking load of the matrix material, the multi-crack cracking degree of the matrix is weakened, the crack control capability is poor, and with the increase of the load, the cracks can quickly form large cracks, so that the polymer grid is separated from the matrix, and the reinforcement effect of the polymer grid is greatly reduced. It follows that the reinforcing effect of the polymeric network is very limited when the ductility and strength of the matrix material are insufficient. In example 4, the polymeric mesh is arranged on the basis of improving the mechanical property of the matrix material by using a multi-scale enhancing means, so that on one hand, the strength and ductility of the matrix material can be improved, and on the other hand, the nano-scale and micro-scale materials can also improve additional connection points on the matrix around the polymeric mesh, thereby improving the bonding property. Due to the two reasons, the polymer grid and the matrix material can well exert a synergistic working effect, and finally, the performance of the polymer grid reinforced material is further improved.
TABLE 2 comparison of tensile strength and tensile ductility of the examples with comparative examples and prior art under the same volume weight (density) conditions
In the description herein, an embodiment means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Although embodiments of the present invention have been shown and described above, it should be understood that the above embodiments are illustrative and not restrictive, and that those skilled in the art may make changes, modifications, substitutions and alterations to the above embodiments without departing from the scope of the present invention.
Claims (11)
1. A lightweight high ductility cement-based composite material based on multi-scale reinforcement, characterized by comprising a mixture of:
the mass fraction of the gelled material 490-870 parts,
392 portions of the mineral admixture 220,
195-330 parts of light filler,
20-40 parts of nano-scale reinforcing material,
15-30 parts of micron-scale reinforcing material,
15-20 parts of a millimeter-scale reinforcing material,
240 parts of water 213 and 75-85 parts of admixture.
2. The lightweight high ductility cement-based composite material according to claim 1, further comprising a plurality of polymeric meshes, wherein said mixture wraps said polymeric meshes to form a polymeric mesh/LHDCC stressed monolith.
3. The lightweight high ductility cement-based composite material according to claim 1, wherein the cementitious material is one or more of silicate cement, aluminate cement and sulphoaluminate cement;
the mineral admixture is one or more of slag powder, fly ash and silica fume;
the light filler is one or more of fly ash hollow microspheres, glass hollow microspheres, expanded perlite and expanded vermiculite, and the particle size range is 10-300 mu m.
4. The lightweight high ductility cement-based composite material as claimed in claim 1, wherein the nano-scale reinforcing material comprises one or more of nano silica particles, nano calcium silicate particles, and nano calcium carbonate particles, and the average particle size of the particles is 40nm or less.
5. The lightweight high ductility cement-based composite material as claimed in claim 1, wherein the micrometer-scale reinforcing material comprises one or more of calcium carbonate whiskers and calcium sulfate whiskers, and has a diameter of 100-200nm and a length of 50-80 μm.
6. The lightweight high ductility cement-based composite material as claimed in claim 1, wherein the millimeter scale reinforcing material comprises one or more of polyethylene fiber, aramid fiber, polybenzobisoxazole fiber, the fiber diameter is 12-50 μm, and the length is greater than or equal to 12 mm.
7. The lightweight high ductility cement-based composite material as claimed in claim 1, wherein said admixture comprises a water reducing agent having a water reducing rate of 30% or more.
8. The lightweight high ductility cement-based composite material according to claim 2, wherein the polymeric mesh comprises one or more combinations of fiber reinforced polymer mesh, geopolymer mesh, iron wire mesh, steel strand mesh.
9. The lightweight high ductility cement-based composite material according to claim 8, wherein the polymeric grid line spacing is 10-40mm and the grid thickness is 0.8-5 mm;
the number of the layers of the polymerization grid arrangement is 0-3, and the distance between every two layers is 4-6 mm;
the mixture forms a coating on the polymeric mesh having a thickness greater than 4 mm.
10. The preparation method of the light-weight high-ductility cement-based composite material comprises the following steps:
(1) weighing a cementing material, a mineral admixture, a light filler, a nanoscale reinforcing material, a microscale reinforcing material, a millimeter-scale reinforcing material, water and an admixture in parts by weight;
(2) uniformly mixing and stirring the gelled material, the mineral admixture and the light filler to obtain a dry material;
(3) fully mixing water, an additive, a nanoscale reinforcing material and a microscale reinforcing material to obtain a liquid material;
(4) adding the liquid material into the dry material, and uniformly mixing and stirring to obtain slurry;
(5) adding a millimeter-scale reinforcing material into the slurry, and uniformly stirring to obtain a fresh mixture;
(6) and then pouring the newly-mixed mixture into a die cavity with a plurality of layers of polymerization grids arranged in parallel at intervals, embedding the newly-mixed mixture into holes and gaps of each layer of polymerization grids, wrapping the polymerization grids, and hardening the mixture to form a polymerization grid/LHDCC stressed whole.
11. The production method according to claim 10,
in the step (3), water, the admixture, the nanoscale reinforcing material and the microscale reinforcing material are fully mixed, and the ultrasonic treatment is carried out for 15min in an ultrasonic instrument with the power of 80W.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111590723.8A CN114057456B (en) | 2021-12-23 | 2021-12-23 | Multi-scale reinforced light high-ductility cement-based composite material and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111590723.8A CN114057456B (en) | 2021-12-23 | 2021-12-23 | Multi-scale reinforced light high-ductility cement-based composite material and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114057456A true CN114057456A (en) | 2022-02-18 |
| CN114057456B CN114057456B (en) | 2023-03-10 |
Family
ID=80230232
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111590723.8A Active CN114057456B (en) | 2021-12-23 | 2021-12-23 | Multi-scale reinforced light high-ductility cement-based composite material and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114057456B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114907077A (en) * | 2022-06-07 | 2022-08-16 | 浙江建设职业技术学院 | Fiber woven mesh reinforced nanometer cement-based composite material and preparation method thereof |
| CN115417631A (en) * | 2022-09-16 | 2022-12-02 | 中南大学 | Low-shrinkage low-creep concrete serving in plateau complex environment and preparation method thereof |
| CN116425480A (en) * | 2023-03-24 | 2023-07-14 | 东南大学 | Light ultra-high-ductility cement-based composite material, design method and preparation method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080242769A1 (en) * | 2006-07-14 | 2008-10-02 | Bjorn Birgisson | Nanomodified concrete additive and high performance cement paste and concrete therefrom |
| CN107514268A (en) * | 2017-06-29 | 2017-12-26 | 昆明理工大学 | A kind of high ductility tunnel support structure across active fault |
| CN110627442A (en) * | 2019-10-14 | 2019-12-31 | 北京工业大学 | Fiber grid reinforced hybrid fiber high-strength and high-ductility cement-based composite material manhole cover and preparation method thereof |
| CN112694342A (en) * | 2021-02-02 | 2021-04-23 | 上海建工建材科技集团股份有限公司 | Lightweight high-strength high-ductility cement-based cementing composite material and preparation method thereof |
| CN113620674A (en) * | 2021-09-10 | 2021-11-09 | 中南林业科技大学 | Green and economical high-ductility cement-based composite material and preparation method thereof |
-
2021
- 2021-12-23 CN CN202111590723.8A patent/CN114057456B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080242769A1 (en) * | 2006-07-14 | 2008-10-02 | Bjorn Birgisson | Nanomodified concrete additive and high performance cement paste and concrete therefrom |
| CN107514268A (en) * | 2017-06-29 | 2017-12-26 | 昆明理工大学 | A kind of high ductility tunnel support structure across active fault |
| CN110627442A (en) * | 2019-10-14 | 2019-12-31 | 北京工业大学 | Fiber grid reinforced hybrid fiber high-strength and high-ductility cement-based composite material manhole cover and preparation method thereof |
| CN112694342A (en) * | 2021-02-02 | 2021-04-23 | 上海建工建材科技集团股份有限公司 | Lightweight high-strength high-ductility cement-based cementing composite material and preparation method thereof |
| CN113620674A (en) * | 2021-09-10 | 2021-11-09 | 中南林业科技大学 | Green and economical high-ductility cement-based composite material and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 李黎等: "纤维增强水泥基复合材料的纤维混杂效应研究进展", 《应用基础与工程科学学报》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114907077A (en) * | 2022-06-07 | 2022-08-16 | 浙江建设职业技术学院 | Fiber woven mesh reinforced nanometer cement-based composite material and preparation method thereof |
| CN115417631A (en) * | 2022-09-16 | 2022-12-02 | 中南大学 | Low-shrinkage low-creep concrete serving in plateau complex environment and preparation method thereof |
| CN115417631B (en) * | 2022-09-16 | 2023-08-22 | 中南大学 | Low-shrinkage low-creep concrete serving in complex plateau environment and preparation method thereof |
| CN116425480A (en) * | 2023-03-24 | 2023-07-14 | 东南大学 | Light ultra-high-ductility cement-based composite material, design method and preparation method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114057456B (en) | 2023-03-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN114057456B (en) | Multi-scale reinforced light high-ductility cement-based composite material and preparation method thereof | |
| Du et al. | New development of ultra-high-performance concrete (UHPC) | |
| Aygörmez et al. | Elevated temperature, freezing-thawing and wetting-drying effects on polypropylene fiber reinforced metakaolin based geopolymer composites | |
| Qaidi et al. | Ultra-high-performance geopolymer concrete: A review | |
| Ahmed et al. | Flexural strength and failure of geopolymer concrete beams reinforced with carbon fibre-reinforced polymer bars | |
| Abbas et al. | Ultra-high performance concrete: Mechanical performance, durability, sustainability and implementation challenges | |
| US7744690B2 (en) | Blast-resistant concrete also suitable for limiting penetration of ballistic fragments | |
| Venu et al. | Tie-confinement aspects of fly ash-GGBS based geopolymer concrete short columns | |
| CN106396548A (en) | Impact-resistant and corrosion-proof cement-based composite material and preparation method thereof | |
| Zhang et al. | Compressive behaviours, splitting properties, and workability of lightweight cement concrete: the role of fibres | |
| CN105016670A (en) | Concrete annular pole and preparation method thereof | |
| CN109836096A (en) | A kind of very-high performance lightweight concrete and preparation method thereof | |
| Cheah et al. | The structural behaviour of HCWA ferrocement–reinforced concrete composite slabs | |
| CN110105011A (en) | A kind of microlith aggregate concrete with the high ductility of lower shrinkage | |
| Mousavi et al. | Influence of mixture composition on the structural behaviour of reinforced concrete beam-column joints: A review | |
| CN111187042A (en) | Light high-strength concrete and preparation method thereof | |
| Jonsung et al. | Sustainable concrete technology | |
| Alexander et al. | Studies on the mechanical and durability performance of textile reinforced geopolymer concrete beams | |
| CN116283168A (en) | Self-stress desert sand ultra-high ductility concrete and preparation method thereof | |
| Jhatial et al. | Influence of long polypropylene fibre on the properties of concrete | |
| CN113968705B (en) | Multi-element gel system STC (concrete-time-dependent temperature) ultrahigh-toughness concrete material for bridge deck pavement | |
| KR101713022B1 (en) | Fiber reinforced concrete composite materials based on alkali activating slag and concrete application produced by the same | |
| CN112960951A (en) | Precast structure combined by concrete and fiber composite bars and concrete preparation method | |
| Dinh et al. | Experimental investigation on flexural and direct shear behaviors of specimens made of lightweight carbon textile‐reinforced cementitious composites | |
| Bedwiy et al. | Post-cracking behavior of cementitious composite incorporating nano-silica and basalt fiber pellets |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |