CN113105174A - Anti-collision damping unit structure and preparation method thereof - Google Patents
Anti-collision damping unit structure and preparation method thereof Download PDFInfo
- Publication number
- CN113105174A CN113105174A CN202110258274.0A CN202110258274A CN113105174A CN 113105174 A CN113105174 A CN 113105174A CN 202110258274 A CN202110258274 A CN 202110258274A CN 113105174 A CN113105174 A CN 113105174A
- Authority
- CN
- China
- Prior art keywords
- damping unit
- strength
- concrete material
- unit structure
- spring
- 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
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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B1/00—Producing shaped prefabricated articles from the material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B11/00—Apparatus or processes for treating or working the shaped or preshaped articles
- B28B11/24—Apparatus or processes for treating or working the shaped or preshaped articles for curing, setting or hardening
- B28B11/245—Curing concrete articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28C—PREPARING CLAY; PRODUCING MIXTURES CONTAINING CLAY OR CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28C5/00—Apparatus or methods for producing mixtures of cement with other substances, e.g. slurries, mortars, porous or fibrous compositions
- B28C5/40—Mixing specially adapted for preparing mixtures containing fibres
- B28C5/402—Methods
-
- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01F—ADDITIONAL WORK, SUCH AS EQUIPPING ROADS OR THE CONSTRUCTION OF PLATFORMS, HELICOPTER LANDING STAGES, SIGNS, SNOW FENCES, OR THE LIKE
- E01F15/00—Safety arrangements for slowing, redirecting or stopping errant vehicles, e.g. guard posts or bollards; Arrangements for reducing damage to roadside structures due to vehicular impact
- E01F15/02—Continuous barriers extending along roads or between traffic lanes
- E01F15/08—Continuous barriers extending along roads or between traffic lanes essentially made of walls or wall-like elements ; Cable-linked blocks
- E01F15/081—Continuous barriers extending along roads or between traffic lanes essentially made of walls or wall-like elements ; Cable-linked blocks characterised by the use of a specific material
- E01F15/083—Continuous barriers extending along roads or between traffic lanes essentially made of walls or wall-like elements ; Cable-linked blocks characterised by the use of a specific material using concrete
-
- 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
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Abstract
The invention discloses an anti-collision damping unit structure and a preparation method thereof, wherein a concrete material is prepared into a spring shape, and the concrete material is an ultrahigh-strength high-ductility concrete material with the compressive strength of more than 150MPa and the ductility of more than 0.3% under uniaxial compression load. According to the invention, the ultrahigh-strength high-ductility concrete material is used as a base body, and the spring design principle is combined, so that the concrete material is prepared into a spring shape to be used as a damping unit structure in a highway anti-collision wall body or a guardrail, high energy caused by external violent impact can be dissipated, the high-strength anti-collision highway anti-collision guardrail has good buffer force, rebound force and impact resistance, and meanwhile, on the premise of ensuring the strength and ductility, the consumption of raw materials is reduced to the greatest extent, and the production cost is reduced.
Description
Technical Field
The invention relates to the technical field of anti-collision facilities, in particular to a damping structure unit and a preparation method thereof.
Background
At present, the highway protective wall mostly adopts rigid materials as safety facilities. However, the main purpose of the rigid material is to protect the vehicle from breaking through, passing down, and crossing to the outside of the road when the vehicle is impacted against the protective wall, and the protective effect is very small for the impact hazard of people and vehicles. This is mainly due to the fact that rigid materials are less capable in absorbing and dissipating the high energy caused by a violent impact. Therefore, there is a need for a vehicle that will effectively intercept a violent impact, yet absorb and dissipate high energy levels, thereby reducing the danger to personnel and vehicles from the impact.
Disclosure of Invention
The purpose of the invention is as follows: the invention aims to provide an anti-collision damping unit structure, which is characterized in that an ultra-high-strength and high-ductility cement-based composite material is made into a spring shape to serve as the damping unit structure in combination with the design structure of a spring, so that under the condition of violent impact of a vehicle, energy can be absorbed and dissipated through multi-slit cracking of the material and the shape effect of the spring, and certain rigidity can be ensured; the invention also aims to provide a preparation method of the anti-collision damping unit structure.
The technical scheme is as follows: the anti-collision damping unit structure is made of concrete materials into a spring shape, and the concrete materials are ultra-high-strength high-ductility concrete materials with the compressive strength larger than 150MPa and the ductility larger than 0.3% under uniaxial compression load.
The damping unit spring is made of concrete materials, the concrete materials are prepared into a spring shape by combining the design principle of the spring, and the concrete materials take cement, silica fume, fibers and aggregate as raw materials.
Wherein, the free height H of the spring of the damping unit structure is 400-800mm, the middle diameter D of the spring is 200-350mm, the diameter D of the spring wire is 20-40mm, the number of effective turns n is 5-10, and the pitch t is 10-30 mm. The shape parameters of the damping unit spring are defined, on one hand, the strain hardening characteristics of the material can be realized, more energy can be absorbed and dissipated, and on the other hand, the production cost of the material can be effectively controlled by matching the shape parameters.
The concrete material comprises the following components in parts by weight: 55-92 parts of cement, 8-42 parts of silica fume, 15-45 parts of sand, 15-22 parts of water, 1.5-2.4 parts of fiber, 1.2-3.5 parts of water reducing agent and 1.5-3 parts of defoaming agent.
The cement is at least one or more of early strength portland cement, sulphoaluminate cement, ordinary portland cement and composite portland cement, and the 28-day compressive strength of the cement is more than or equal to 52.5MPa, and the flexural strength of the cement is more than or equal to 7 MPa. The variety and 28-day compressive strength of the cement are limited to be more than or equal to 52.5MPa, the breaking strength is more than or equal to 7MPa, the ultrahigh strength and high ductility concrete material is mainly ensured to have ultrahigh strength, and if the ultrahigh strength and high ductility concrete material exceeds a limited range, the strength of the ultrahigh strength and high ductility concrete material is influenced.
The silica fume is silicon dioxide with the mass percent of more than 90 percent; wherein, the mass percentage of the silicon dioxide with the particle size less than 1 μm in the silicon dioxide is more than 40 percent. The content of the silicon ash is limited, the ultrahigh strength of the ultrahigh-strength ultrahigh-compressibility concrete material is mainly considered, the theoretical calculation of closest particle packing is carried out, the volcanic ash effect in the later period is guaranteed by the high content of silicon dioxide in the silicon ash and the nanometer level of particle size, the substrate micro-pore structure is effectively filled, and the compactness of a fiber/interface is increased, so that the ultrahigh strength, frost resistance, impermeability and corrosion resistance of the ultrahigh-strength ultrahigh-compressibility concrete material are realized.
The sand is at least one of quartz sand, river sand and machine-made sand, for example, one or two of the quartz sand, the river sand and the machine-made sand are compounded, the particle size is 0.075-0.6 mm, and the average particle size is 0.26-0.32 mm. The size range of the sand is limited, and a large number of theoretical and experimental researches show that the average size of the aggregate is less than 0.26mm or more than 0.32mm, and the minimum size is less than 0.075mm or more than 0.6mm, which can seriously affect the uniformity of the fiber and the particle close packing of the mixture, thereby affecting the strain capacity and the strength of the ultra-high strength and high ductility concrete material.
The fiber of the invention is at least one or more than two of ultra-high molecular weight synthetic polyethylene fiber, Kevlar fiber, poly (p-phenylene benzobisoxazole) fiber, carbon fiber and poly (ethylene terephthalate) fiber; the length of the fiber is 8-18 mm, the diameter is 20-50 μm, the tensile strength is more than or equal to 2100MPa, and the tensile elastic modulus is more than or equal to 80 GPa. The variety, the performance and the mixing amount of the fiber are critical, the fiber is limited, and the ductility of the ultrahigh-strength high-ductility concrete material can be seriously influenced beyond the range after the main calculation of the design theory of the ultrahigh-strength high-ductility cement-based composite material.
The water reducing agent is a liquid polycarboxylic acid water reducing agent, the solid content in the water reducing agent is more than 30 percent, and the water reducing rate is more than 40 percent. The water reducing agent is limited, the preparation process of the ultra-high strength and high ductility concrete material is mainly considered, and particularly when the silica fume mixing amount is higher, the fresh slurry body is seriously influenced if the silica fume mixing amount exceeds the range, so that the strength and ductility of the ultra-high strength and high ductility concrete material are influenced.
The defoaming agent of the present invention is
At least one or more than two of the high-efficiency antifoaming agent and the SPT-DF30 water-based high-efficiency antifoaming agent are compounded. The defoaming agent has the function of eliminating bubbles in the matrix of the ultrahigh-strength high-ductility concrete material, and tests show that,
the high-efficiency defoaming agent and the SPT-DF30 water-based high-efficiency defoaming agent have better effects.
The invention also provides a preparation method of the anti-collision damping unit structure, which comprises the following steps:
(1) mixing and stirring cement, silica fume and sand to obtain a dry mixture;
(2) mixing and stirring a water reducing agent, a defoaming agent and water to obtain a mixed solution;
(3) pouring the mixed solution into the dry mixture, stirring to obtain an ultrahigh-strength and high-ductility concrete material matrix, adding fibers into the matrix, and uniformly dispersing the fibers in the matrix by stirring treatment to obtain the ultrahigh-strength and high-ductility concrete material containing the fibers;
(4) and (3) injecting the ultrahigh-strength high-ductility concrete material containing the fibers into a mold, coiling the mold into a spring shape, and removing the mold for maintenance after maintenance molding to obtain the anti-collision damping unit structure. Wherein the curing conditions are as follows: and (3) curing for 28 days in an environment with the temperature of 18-22 ℃ and the relative humidity of more than 90%.
The preparation method comprises the following steps:
(1) dry-mixing cement, silica fume and sand in certain weight parts for 3-6 min by using a stirrer to obtain a uniformly-mixed dry-mixed material;
(2) mixing and stirring a certain weight part of water reducing agent, a defoaming agent and water for 2-4 min to obtain a uniformly mixed liquid;
(3) pouring the mixed solution into the dry mixture and stirring for 6-10 min to obtain a uniformly mixed ultrahigh-strength high-ductility concrete material matrix;
(4) adding the fibers into the matrix and stirring for 5-7 min to ensure that the fibers are fully and uniformly dispersed in the ultrahigh-strength high-ductility concrete material matrix;
(5) injecting the ultrahigh-strength high-ductility concrete material containing the fibers into a corrugated pipe mold meeting design requirements by using a high-pressure gun for molding, and manufacturing the corrugated pipe into a spring shape according to the design requirements;
(6) and (3) removing the mold, and maintaining the spring sample after mold removal in an environment with the temperature of 18-22 ℃ and the relative humidity of more than 90% for 28 days to obtain the damping unit spring concrete material.
Ultra-high strength high ductility cement-based composites are defined as novel fiber reinforced cement-based composites with high toughness, high ductility and durability. In the stress process of the ultrahigh-strength high-ductility cement-based composite material, due to the bridging effect of fibers at a crack and the stable expansion of cracks during stress transmission between the fibers and a matrix, the ultrahigh-strength high-ductility cement-based composite material shows obvious multi-crack cracking characteristics and strain hardening behaviors. The design structure of the spring is combined, the ultrahigh-strength high-ductility cement-based composite material is made into a spring shape to be used as a damping unit structure in a highway anti-collision wall body or a guardrail, under the condition of violent vehicle impact, energy can be absorbed and dissipated through multi-slit cracking of the material and the shape effect of the spring, certain rigidity can be guaranteed, and vehicle breakthrough, underpass and overturn to the outer side of a highway are avoided. In addition, the spring-shaped design can reduce the self weight and the production cost.
In the prior art, the anti-collision structure mostly adopts a cast-in-place method or a prefabricated assembly method. The cast-in-place method needs a support template, is not beneficial to shortening the construction period, cannot ensure the quality, and is not easy to repair in time once damaged. The prefabricated assembly type method is mainly characterized in that reinforced concrete units are combined with metal components, and the anti-collision and anti-impact performance is achieved through physical matching and combination. However, the construction process of the prefabricated assembly type method is complicated and tedious, the adopted structural units are mostly made of rigid materials, and the anti-collision and anti-impact performance is achieved only through physical matching and combination. In addition, once the collision happens, the road needs to be replaced in time, and the road can be ensured to be smooth. The durability of the metallic materials involved is questionable, since they are susceptible to corrosion in the long term outdoors.
The technical difficulties of the invention are two: firstly, the compressive strength is more than 150MPa, the ductility under uniaxial compression load is more than 0.3%, and the selection of raw materials is not simply realized by random combination, but is preferably realized by combining the closest packing theory, the micro fracture mechanics theory and the statistical theory on the performance and the proportion of the raw materials; secondly, in the forming process of the spring member, it is known that the workability of concrete is seriously reduced by doping a large amount of fibers into the concrete, and how to realize the preparation of the concrete with a large amount of fibers into a spring shape becomes a technical difficulty.
The anti-collision damping unit structure takes concrete materials as a reference, combines a spring design principle, prepares the concrete materials into a spring shape, and takes cement, silica fume, fibers and aggregates as raw materials, and obtains the ultra-high strength and high ductility concrete materials with the compression strength of more than 150MPa and the ductility of more than 0.3 percent under the condition of single-axis compression load after scientific mixing treatment; the invention takes the concrete material with ultrahigh strength and high ductility as a matrix, combines the spring design principle, prepares the concrete material into a spring shape to be used as a damping unit structure in the highway anti-collision wall body or the guardrail, can dissipate high energy caused by external violent impact, has good buffer force, rebound force and impact resistance, can effectively prevent and reduce the damage of the vehicle out of control to the anti-collision wall body or the guardrail after impact on personnel and vehicles, and has the advantages of long service life and low use cost; meanwhile, on the premise of ensuring the strength and the ductility, the consumption of raw materials is reduced to the greatest extent, and the production cost is reduced.
Has the advantages that: the invention utilizes the multi-crack cracking property and the strain hardening behavior of the ultrahigh-strength high-ductility concrete material and combines the design principle of the spring to manufacture the ultrahigh-strength high-ductility concrete material into the spring shape, under the condition of violent impact of a vehicle, the energy can be absorbed and dissipated through the multi-crack cracking of the material and the shape effect of the spring, the safety of the vehicle and personnel can be ensured, certain rigidity can be ensured, and the vehicle can be prevented from breaking through, passing down and turning over to the outer side of a road. In addition, the spring-shaped design can reduce the self weight and the production cost.
The preparation method of the spring concrete material for the damping unit of the highway anti-collision wall body is simple, convenient to operate and suitable for anti-collision walls of traffic transportation networks such as expressways, urban overpasses and elevated roads.
Drawings
Fig. 1 is a schematic structural view of a damping unit spring of a road anti-collision wall body of the invention.
Detailed Description
The present invention will be described in further detail with reference to examples.
Fig. 1 shows a crash damping unit structure according to the present invention, in which: h is the height of the damper, t is the pitch, D is the pitch diameter of the damper, and D is the diameter of the damper material.
Example 1:
a preparation method of a damping unit spring for a highway anti-collision wall body comprises the following steps of:
table 1 spring concrete material parameter indexes of damping units of anti-collision wall of highway in embodiment 1
The cement is early-strength portland cement; the fiber is a synthetic polyethylene fiber with ultrahigh molecular weight, the length of the fiber is 8mm, and the fiber is straightThe diameter is 38 mu m; the defoaming agent is
High-efficiency defoaming agent.
The preparation method comprises the following steps:
(1) dry-mixing cement, silica fume and sand in certain weight parts for 3min by using a stirrer to obtain a uniformly-mixed dry-mixed material;
(2) mixing and stirring a certain weight part of water reducing agent, a defoaming agent and water for 4min to obtain a uniformly mixed liquid;
(3) pouring the mixed solution into the dry mixture and stirring for 6min to obtain a uniformly mixed ultrahigh-strength high-ductility concrete material matrix;
(4) adding the fibers into the matrix and stirring for 7min to ensure that the fibers are fully and uniformly dispersed in the ultrahigh-strength high-ductility concrete material matrix;
(5) injecting the ultrahigh-strength high-ductility concrete material containing the fibers into a mold for molding by using a high-pressure gun; coiling to spring shape according to design requirements;
(6) and (3) removing the mold, and maintaining the spring sample after mold removal in an environment with the temperature of 18-22 ℃ and the relative humidity of more than 90% for 28 days to obtain the damping unit spring concrete material.
The stirrer is a body type stirrer, and the rotating speed is 285 r/min; the mold is an ABS corrugated pipe plastic mold.
And comparative examples 1-1 were set, and the preparation raw materials were substantially the same as in example 1, except that comparative examples 1-1 had only fibers removed from the blend ratio, and the rest of the blend ratio, the physical index of the spring, and the preparation procedure were the same as in example 1. Comparative examples 1 to 2 were set, and the preparation raw materials were substantially the same as in example 1, except that comparative examples 1 to 2 were molded using a 40mm x 40mm mold only in the molding process of the preparation step, for testing the compression strength and the compression strain in the non-spring state.
Example 2:
the matching proportion of the damping unit spring for the anti-collision wall of the highway is shown in a table 2.
Table 2 spring concrete material parameter indexes of damping units of anti-collision wall of highway in embodiment 2
Wherein the cement is early strength portland cement; the fiber is an ultrahigh molecular weight synthetic polyethylene fiber with the length of 12mm and the diameter of 50 μm; the defoaming agent is
High-efficiency defoaming agent.
The invention provides a preparation method of a damping unit spring concrete material for a road anti-collision wall body, which comprises the following steps:
1) dry-mixing the cement, the silica fume and the river sand for 6min by using a stirrer to obtain a uniformly-mixed dry-mixed material;
2) mixing and stirring a water reducing agent, a defoaming agent and water for 2min to obtain a uniformly mixed liquid;
3) pouring the mixed solution into the dry mixture and stirring for 10min to obtain a uniformly mixed ultrahigh-strength high-ductility concrete material matrix;
4) adding the ultra-high molecular weight synthetic polyethylene fibers into the mortar and stirring for 5min to ensure that the fibers are fully and uniformly dispersed in the ultra-high strength and high ductility concrete material matrix;
5) pouring the ultrahigh-strength high-ductility concrete material containing the fibers into a mold for molding, and covering a plastic film for curing;
6) and (3) removing the mold, and maintaining the spring sample after mold removal in an environment with the temperature of 18-22 ℃ and the relative humidity of more than 90% for 28 days to obtain the damping unit spring concrete material.
The stirrer is a body type stirrer, and the rotating speed is 500 r/min; the mold is an ABS corrugated pipe plastic mold.
And set up comparative example 2-1, prepare raw materials basically the same as example 2, the difference is that comparative example 2-1 has only removed the fiber in the mix proportion, the other mix proportion, spring physical index and preparation step are the same as example 2. Comparative examples 2-2 were set up, and the production raw materials were substantially the same as in example 2, except that comparative examples 2-2 were molded using a 40mm x 40mm mold only during the molding in the production steps, for testing the compression strength and the compression strain in the non-spring state.
Example 3:
the mix proportion of the damping unit springs of the highway anti-collision wall is shown in a table 3:
table 3 spring concrete material parameter indexes of road anti-collision wall damping unit in embodiment 3
The cement is early-strength portland cement; the fiber is poly-p-phenylene benzobisoxazole fiber, the length is 15mm, and the diameter is 20 mu m; the defoaming agent is an SPT-DF30 water-based efficient defoaming agent.
The invention provides a preparation method of a damping unit spring concrete material for a road anti-collision wall body, which comprises the following steps:
1) dry-mixing the cement, the silica fume and the river sand for 4min by a stirrer to obtain a uniformly-mixed dry-mixed material;
2) mixing and stirring a water reducing agent, a defoaming agent and water for 3min to obtain a uniformly mixed liquid;
3) pouring the mixed solution into the dry mixture and stirring for 8min to obtain a uniformly mixed ultrahigh-strength high-ductility concrete material matrix;
4) adding the ultra-high molecular weight synthetic polyethylene fibers into the mortar and stirring for 5min to ensure that the fibers are fully and uniformly dispersed in the ultra-high strength and high ductility concrete material matrix;
5) pouring the ultrahigh-strength high-ductility concrete material containing the fibers into a mold for molding, and covering a plastic film for curing;
6) and (3) removing the mold, and maintaining the spring sample after mold removal in an environment with the temperature of 18-22 ℃ and the relative humidity of more than 90% for 28 days to obtain the damping unit spring concrete material.
The stirrer is a body type stirrer, and the rotating speed is 400 r/min; the mold is an ABS corrugated pipe plastic mold.
And set up comparative example 3-1, prepare raw materials basically the same as example 3, except that comparative example 3-1 has removed the fiber in the mix proportion only, the other mix proportion, spring physical index and preparation step are the same as example 3. Comparative example 3-2 was set, and the preparation raw materials were substantially the same as in example 3, except that comparative example 3-2 was molded using a 40mm x 40mm mold only during the molding in the preparation step, for testing the compression strength and the compression strain in the non-spring state.
Example 4:
the matching proportion of the damping unit spring for the anti-collision wall of the highway is shown in a table 4.
Table 4 spring concrete material parameter indexes of road anti-collision wall damping unit in embodiment 4
The cement is early-strength portland cement; the fiber is Kevlar fiber, the length is 12mm, and the diameter is 24 μm; the defoaming agent is
High-efficiency defoaming agent.
The invention provides a preparation method of a damping unit spring concrete material for a road anti-collision wall body, which comprises the following steps:
1) dry-mixing the cement, the silica fume and the river sand for 3min by using a stirrer to obtain a uniformly-mixed dry-mixed material;
2) mixing and stirring a water reducing agent, a defoaming agent and water for 2min to obtain a uniformly mixed liquid;
3) pouring the mixed solution into the dry mixture and stirring for 8min to obtain a uniformly mixed ultrahigh-strength high-ductility concrete material matrix;
4) adding the ultra-high molecular weight synthetic polyethylene fibers into the mortar and stirring for 5min to ensure that the fibers are fully and uniformly dispersed in the ultra-high strength and high ductility concrete material matrix;
5) pouring the ultrahigh-strength high-ductility concrete material containing the fibers into a mold for molding, and covering a plastic film for curing;
6) and (3) removing the mold, and maintaining the spring sample after mold removal in an environment with the temperature of 18-22 ℃ and the relative humidity of more than 90% for 28 days to obtain the damping unit spring concrete material.
The stirrer is a body type stirrer, and the rotating speed is 140 r/min; the mold is a PVA corrugated pipe mold.
And set up comparative example 4-1, prepare raw materials basically the same as example 4, except that comparative example 4-1 has removed the fiber in the mix proportion only, the other mix proportion, spring physical index and preparation step are the same as example 4. Comparative example 4-2 was set, and the preparation raw materials were substantially the same as in example 4, except that comparative example 4-2 was molded using a 40mm x 40mm mold only during the molding in the preparation step, for testing the compression strength and the compression strain in the non-spring state.
Example 5:
the matching proportion of the damping unit spring for the anti-collision wall of the highway is shown in a table 5.
Table 5 spring concrete material parameter indexes of damping units of anti-collision wall of highway in embodiment 5
The cement is sulphoaluminate cement; the fiber is polyethylene terephthalate fiber, the length is 18mm, and the diameter is 20 mu m; the defoaming agent is
High-efficiency defoaming agent.
The invention provides a preparation method of a damping unit spring concrete material for a road anti-collision wall body, which comprises the following steps:
1) dry-mixing the cement, the silica fume and the river sand for 3min by using a stirrer to obtain a uniformly-mixed dry-mixed material;
2) mixing and stirring a water reducing agent, a defoaming agent and water for 4min to obtain a uniformly mixed liquid;
3) pouring the mixed solution into the dry mixture and stirring for 8min to obtain a uniformly mixed ultrahigh-strength high-ductility concrete material matrix;
4) adding the ultra-high molecular weight synthetic polyethylene fibers into the mortar and stirring for 6min to ensure that the fibers are fully and uniformly dispersed in the ultra-high strength and high ductility concrete material matrix;
5) pouring the ultrahigh-strength high-ductility concrete material containing the fibers into a mold for molding, and covering a plastic film for curing;
6) and (3) removing the mold, and maintaining the spring sample after mold removal in an environment with the temperature of 18-22 ℃ and the relative humidity of more than 90% for 28 days to obtain the damping unit spring concrete material.
The stirrer is a body type stirrer, and the rotating speed is 140 r/min; the mold is a PVA corrugated pipe mold.
And set up comparative example 5-1, prepare raw materials basically the same as example 5, except that comparative example 5-1 has removed the fiber in the mix proportion only, the other mix proportion, spring physical index and preparation step are the same as example 5. Comparative example 5-2 was set, and the preparation raw materials were substantially the same as in example 5, except that comparative example 5-2 was molded using a 40mm x 40mm mold only during the molding in the preparation step, for testing the compression strength and the compression strain in the non-spring state.
Example 6:
the matching proportion of the damping unit spring for the anti-collision wall of the highway is shown in a table 6.
Table 6 parameter indexes of spring concrete material of damping unit of anti-collision wall body for road in embodiment 6
The cement is ordinary portland cement; the fiber is an ultrahigh molecular weight synthetic polyethylene fiber with the length of 18mm and the diameter of 50 μm; the defoaming agent is
High-efficiency defoaming agent.
The invention provides a preparation method of a damping unit spring concrete material for a road anti-collision wall body, which comprises the following steps:
1) dry-mixing the cement, the silica fume and the river sand for 6min by using a stirrer to obtain a uniformly-mixed dry-mixed material;
2) mixing and stirring a water reducing agent, a defoaming agent and water for 4min to obtain a uniformly mixed liquid;
3) pouring the mixed solution into the dry mixture and stirring for 10min to obtain a uniformly mixed ultrahigh-strength high-ductility concrete material matrix;
4) adding the ultra-high molecular weight synthetic polyethylene fibers into the mortar and stirring for 7min to ensure that the fibers are fully and uniformly dispersed in the ultra-high strength and high ductility concrete material matrix;
5) pouring the ultrahigh-strength high-ductility concrete material containing the fibers into a mold for molding, and covering a plastic film for curing;
6) and (3) removing the mold, and maintaining the spring sample after mold removal in an environment with the temperature of 18-22 ℃ and the relative humidity of more than 90% for 28 days to obtain the damping unit spring concrete material.
The stirrer is a body type stirrer, the rotating speed is 285r/min and the mould is a PVA corrugated pipe mould.
And comparative example 6-1 was set, and the preparation raw materials were substantially the same as in example 6, except that comparative example 6-1 had only fibers removed from the blend ratio, and the rest of the blend ratio, the physical index of the spring, and the preparation steps were the same as in example 6. Comparative example 6-2 was set, and the preparation raw materials were substantially the same as in example 6, except that comparative example 6-2 was molded using a 40mm x 40mm mold only during the molding in the preparation step, for testing the compression strength and the compression strain in the non-spring state.
The highway anti-collision wall damping unit springs prepared in the above examples and comparative examples were tested, and the test results are shown in table 7 below. According to the technical indexes of the test in the table 7, the anti-collision damping unit structure prepared by the invention has excellent compression resistance and compression deformation performance, and can be used as an anti-collision damping unit structure applied to anti-collision walls or guardrails and the like.
TABLE 7 test results of the relevant parameters
Example 7:
five sets of parallel tests are set in the embodiment, the first set is different from the embodiment 1 except the fiber performance, and the other spring physical indexes and the specific preparation process are the same as the embodiment 1. The concrete raw material ratios of the groups 2, 3, 4, 5, 6, 7 and 8 except the concrete raw material ratio are different from those of the example 1, the concrete ratios are shown in the following table 8, and the physical indexes and the concrete preparation process of the spring are the same as those of the example 1.
Wherein, the adopted fiber in the group 1 is polypropylene fiber with the length of 12 mm; diameter of 30 μm, tensile strength of 400MPa, and tensile elastic modulus of 6 GPa. The fibers used in groups 2, 3, 4, 5, 6, 7, 8 were consistent with the fibers of example 1 in performance.
TABLE 8 concrete Material proportioning (parts by weight)
| Numbering | Cement | Silica fume | River sand | Water reducing agent | Defoaming agent | Water (W) | Fiber |
| 1 | 82 | 18 | 35 | 1.2 | 1.5 | 18 | 2.2 |
| 2 | 95 | 5 | 35 | 1.2 | 1.5 | 18 | 2.2 |
| 3 | 50 | 50 | 35 | 1.2 | 1.5 | 18 | 2.2 |
| 4 | 82 | 18 | 50 | 1.2 | 1.5 | 18 | 2.2 |
| 5 | 82 | 18 | 35 | 3.8 | 1.5 | 18 | 2.2 |
| 6 | 82 | 18 | 35 | 1.2 | 3.2 | 18 | 2.2 |
| 7 | 82 | 18 | 35 | 1.2 | 1.5 | 24 | 2.2 |
| 8 | 82 | 18 | 35 | 1.2 | 1.5 | 18 | 2.6 |
The highway anti-collision wall damping unit spring prepared from the raw materials according to the proportion is tested, and the test results are shown in the following table 9.
TABLE 9 test results for relevant parameters
Claims (10)
1. The utility model provides an anticollision damping unit structure which characterized in that: the structure is prepared into a spring shape by adopting a concrete material, the compressive strength of the concrete material is more than 150MPa, and the ductility under uniaxial compression load is more than 0.3%.
2. The pre-crash damping unit structure according to claim 1, wherein: the free height H of the spring of the damping unit structure is 400-800mm, the middle diameter D of the spring is 200-350mm, the diameter D of the spring wire is 20-40mm, the number of effective turns n is 5-10, and the pitch t is 10-30 mm.
3. The pre-crash damping unit structure according to claim 1, wherein: the concrete material comprises the following components in parts by weight: 55-92 parts of cement, 8-42 parts of silica fume, 15-45 parts of sand, 15-22 parts of water, 1.5-2.4 parts of fiber, 1.2-3.5 parts of water reducing agent and 1.5-3 parts of defoaming agent.
4. The pre-crash damping unit structure according to claim 3, wherein: the cement is at least one of early strength portland cement, sulphoaluminate cement, ordinary portland cement and composite portland cement, and the 28-day compressive strength of the cement is more than or equal to 52.5MPa, and the flexural strength of the cement is more than or equal to 7 MPa.
5. The pre-crash damping unit structure according to claim 3, wherein: the silica fume is silicon dioxide with the mass percent of more than 90 percent, wherein the mass percent of the silicon dioxide with the particle size of less than 1 mu m is more than 40 percent.
6. The pre-crash damping unit structure according to claim 3, wherein: the sand is at least one of quartz sand, river sand and machine-made sand, the particle size of the sand is 0.075-0.6 mm, and the average particle size is 0.26-0.32 mm.
7. The pre-crash damping unit structure according to claim 3, wherein: the length of the fiber is 8-18 mm, the diameter is 20-50 μm, the tensile strength is more than or equal to 2100MPa, and the tensile elastic modulus is more than or equal to 80 GPa.
8. The pre-crash damping unit structure according to claim 3, wherein: the fiber is one or more of polyethylene fiber, Kevlar fiber, poly (p-phenylene benzobisoxazole) fiber, carbon fiber and poly (ethylene terephthalate) fiber.
9. The method for preparing an anti-collision damping unit structure according to any one of claims 1 to 8, characterized by comprising the steps of:
(1) mixing and stirring cement, silica fume and sand to obtain a dry mixture;
(2) mixing and stirring a water reducing agent, a defoaming agent and water to obtain a mixed solution;
(3) pouring the mixed solution into the dry mixture, stirring to obtain an ultrahigh-strength and high-ductility concrete material matrix, adding fibers into the matrix, and uniformly dispersing the fibers in the matrix by stirring treatment to obtain the ultrahigh-strength and high-ductility concrete material containing the fibers;
(4) and (3) injecting the ultrahigh-strength high-ductility concrete material containing the fibers into a mold, coiling the mold into a spring shape, and removing the mold for maintenance after maintenance molding to obtain the anti-collision damping unit structure.
10. The method of making a crash damping unit structure according to claim 9, wherein: in the step (4), the curing conditions are as follows: and (3) curing for 28 days in an environment with the temperature of 18-22 ℃ and the relative humidity of more than 90%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110258274.0A CN113105174B (en) | 2021-03-09 | 2021-03-09 | Anti-collision damping unit structure and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110258274.0A CN113105174B (en) | 2021-03-09 | 2021-03-09 | Anti-collision damping unit structure and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113105174A true CN113105174A (en) | 2021-07-13 |
| CN113105174B CN113105174B (en) | 2022-08-26 |
Family
ID=76711724
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110258274.0A Active CN113105174B (en) | 2021-03-09 | 2021-03-09 | Anti-collision damping unit structure and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113105174B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004197475A (en) * | 2002-12-19 | 2004-07-15 | Jfe Steel Kk | Banking structure and method of constructing the same |
| CN106747055A (en) * | 2016-11-23 | 2017-05-31 | 东南大学 | A kind of strong superelevation ductility cement-base composite material of superelevation and preparation method thereof |
-
2021
- 2021-03-09 CN CN202110258274.0A patent/CN113105174B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004197475A (en) * | 2002-12-19 | 2004-07-15 | Jfe Steel Kk | Banking structure and method of constructing the same |
| CN106747055A (en) * | 2016-11-23 | 2017-05-31 | 东南大学 | A kind of strong superelevation ductility cement-base composite material of superelevation and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 柯劲松: "MDF水泥材料的制备与应用", 《中国建材》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113105174B (en) | 2022-08-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9115026B2 (en) | Cementitious matrix and fiber reinforced cement based mixture | |
| CN105948660A (en) | High-strength ultra-high-toughness concrete and preparation method thereof | |
| US9145337B2 (en) | Fiber reinforced cement based mixed material | |
| CN106396548A (en) | Impact-resistant and corrosion-proof cement-based composite material and preparation method thereof | |
| US20070228612A1 (en) | Blast-resistant concrete also suitable for limiting penetration of ballistic fragments | |
| CN110627439B (en) | Ultra-high performance concrete for expansion joint transition area and preparation method thereof | |
| US8915997B2 (en) | Durable concrete and method for producing the same | |
| CN102557555A (en) | Mineral fiber-modified flexible rubber concrete | |
| SA516371014B1 (en) | Concrete element comprising a sound-absorber | |
| Wang et al. | 27 Lightweight engineered cementitious composites (ECC) | |
| CN113816696A (en) | Recycled fine aggregate internal curing-based ultrahigh-performance concrete and preparation method thereof | |
| CN106747055A (en) | A kind of strong superelevation ductility cement-base composite material of superelevation and preparation method thereof | |
| CN114057456B (en) | Multi-scale reinforced light high-ductility cement-based composite material and preparation method thereof | |
| CN111574164A (en) | Rapid repairing material for super-early-strength shrinkage compensation road bridge and preparation method thereof | |
| CN102765919A (en) | Quick patching material for cement concrete pavement and preparation method thereof | |
| CN105946311B (en) | A kind of anti-riot composite plate of superhigh tenacity shock resistance and preparation method thereof | |
| CN113105174B (en) | Anti-collision damping unit structure and preparation method thereof | |
| CN108821699A (en) | A kind of skyscraper high-strength concrete | |
| CN112592114A (en) | Waterproof and antirust material for PC (polycarbonate) component | |
| CN105837101A (en) | Continuous carbon fiber fabric reinforced alkali-activated slag mortar board and preparation method thereof | |
| CN104944858A (en) | High-initial-crack-strain fiber-reinforced polymer-modified cement composite material and preparation method thereof | |
| CN114180989A (en) | Self-made lightweight aggregate, lightweight ultrahigh-strength concrete and preparation method | |
| KR20230020622A (en) | Composition of crack self-healing functional composite, method thereof and high-durable concrete application produced by the same | |
| Sami et al. | Influence of Nano Silica on the compressive strength and flexural behaviour of Bridge rubberised concrete | |
| CN105130297A (en) | Super-fluid PVA fiber concrete and preparation method thereof |
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 |