CN109797788B - Method for reinforcing underwater concrete structure by using ultra-high performance concrete - Google Patents
Method for reinforcing underwater concrete structure by using ultra-high performance concrete Download PDFInfo
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- 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
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Abstract
The invention belongs to the technical field of concrete structure maintenance and reinforcement, and particularly relates to a reinforcement method for reinforcing an underwater concrete structure by using ultra-high performance concrete, which is characterized by comprising the following steps: cleaning the surface of a region to be reinforced, cleaning the foundation of a concrete structure to be reinforced, placing a reinforcement cage, installing a template, pouring broken stones and stone chips, pouring underwater rapid hardening mortar, pouring ultrahigh-performance concrete, and removing the template after maintenance. The invention has the advantages of simple and convenient reinforcing method, obviously improved bearing capacity and durability of the reinforced concrete structure, and the like.
Description
Technical Field
The invention belongs to the technical field of maintenance and reinforcement of concrete structures, and particularly relates to a reinforcement method for reinforcing an underwater concrete structure by using ultra-high performance concrete.
Background
The underwater concrete structure is easy to be damaged due to erosion, harmful ion erosion and collision of water flow, and particularly for a water level change area, the underwater concrete structure is damaged by dry-wet alternation, freeze-thaw cycle and the like, so that the damage condition is more serious, the bearing capacity and durability of the underwater concrete structure are reduced, and the safe use of the upper structure of the underwater concrete structure is threatened. At present, a method mainly adopted for maintaining and reinforcing damaged parts of underwater concrete is a cross section enlarging method, specifically adopted means comprise cofferdam post-reinforcement and underwater pouring anti-dispersion concrete reinforcement, the former has a good reinforcing effect, but the construction period is long and the cost is high, the latter needs to build a large-area construction operation surface, in order to ensure the integrity of a reinforcing material and a pier, underwater bar planting operation is usually needed, the process is complicated, and the reinforcing effect of the reinforcing method is greatly influenced by the construction process and the performance of the underwater anti-dispersion concrete.
Ultra High Performance Concrete (UHPC) is a new type of cement-based composite material with ultra high strength, ultra high toughness and high durability. The research results show that the ultra-high performance concrete has excellent bonding performance with common concrete, and is an ideal concrete structure maintenance reinforcing material. When the ultrahigh-performance concrete with the high tensile strain strengthening characteristic is used for carrying out wrapped maintenance and reinforcement on the concrete structure, the integrity of the ultrahigh-performance concrete and the concrete structure can be ensured even if the concrete structure is not subjected to bar planting operation, and then the process of reinforcement operation is simplified. On the basis, the underwater anti-dispersion capacity of the ultra-high performance concrete is further improved, and the ultra-high performance concrete can be used for safely and efficiently reinforcing an underwater concrete structure. For this reason, it is necessary to develop a reinforcing method for reinforcing an underwater concrete structure using ultra-high performance concrete.
Disclosure of Invention
The invention discloses a method for reinforcing an underwater concrete structure by using ultra-high performance concrete, aiming at the problems of long construction period, high construction cost, unsatisfactory reinforcing effect and the like of the existing method for reinforcing the underwater concrete structure.
In order to achieve the purpose, the technical scheme of the invention is as follows: a method for reinforcing an underwater concrete structure by using ultra-high performance concrete is characterized by comprising the following steps:
step 1: cleaning the surface of the region to be reinforced;
step 2: cleaning a foundation of a concrete structure to be reinforced;
and step 3: placing a reinforcement cage, wherein the reinforcement cage is placed on the foundation of the concrete structure to be reinforced and at least covers the area to be reinforced;
and 4, step 4: installing a template, wherein the template is placed on the foundation of the concrete structure to be reinforced and is positioned outside the reinforcement cage;
and 5: pouring broken stones and stone chips into a gap between the template and the concrete structure to be reinforced;
and 6: pouring underwater quick-hardening mortar;
and 7: pouring the ultra-high performance concrete;
and 8: and (5) removing the mold after maintenance.
In the invention, the area to be reinforced in the step 1 is the damaged part of the concrete structure and the area within the range of 20cm above and below the damaged part, and a diver cleans the surface of the area to be reinforced by using a high-pressure water gun, mainly removing dirt on the surface and loose concrete.
In the invention, in the step 2, the diver finishes the removal of the silt and other impurities on the upper surface of the foundation of the concrete structure to be reinforced, thereby ensuring the surface of the foundation to be smooth.
According to the invention, the reinforcement cage in the step 3 is formed by connecting two symmetrical structures in a binding or welding mode according to the shape of the concrete structure to be reinforced, the reinforcement cage is formed by transverse reinforcements and longitudinal reinforcements, the transverse reinforcements are arranged on the outer side, the reinforcement cage is arranged on the foundation of the concrete structure to be reinforced, and the distance between the reinforcement cage and the inner wall of the template is 20-30 mm.
In the invention, the template in the step 4 is formed by fastening two symmetrical structures through bolts according to the shape of the concrete structure to be reinforced, and the template is placed on the foundation of the concrete structure to be reinforced.
In the invention, in the step 5, the rock chips are poured into the gap between the template and the concrete structure to be reinforced according to the sequence of pouring the rock chips after pouring the rock chips. The macadam is selected from continuous gradation, the maximum grain diameter of the macadam is not more than 1/3 of the reinforcing thickness, the pouring amount is required to ensure that the top of the macadam layer is 300-400 mm away from the lower part of a region to be reinforced, the grain diameter range of the stone chips is 2-10mm, and the pouring thickness is 100-150 mm.
In the invention, the compressive strength of the underwater rapid-hardening mortar selected in the step 6 reaches more than 10MPa after 3 hours of pouring, the pouring port is kept below the surface of the underwater rapid-hardening mortar slurry in the pouring process, and the pouring thickness is 200-250 mm.
In the invention, the step 7 is carried out after the step 6 is finished for 3 hours, and the filling port is kept at a position which is more than or equal to 200mm below the surface of the ultra-high performance concrete slurry in the pouring process.
In the invention, the ultra-high performance concrete selected in the step 7 has high tensile strain strengthening characteristic and good underwater anti-dispersion performance, and in order to realize the characteristics of the ultra-high performance concrete, the raw material composition of the ultra-high performance concrete comprises: the cement, mineral powder, fly ash, silica fume, quartz sand, quartz powder, limestone powder, steel fiber, viscosity regulator, water reducing agent, defoaming agent and water, wherein the weight ratio of the raw materials is as follows:
further, the cement used is one of portland cement or ordinary portland cement, and the strength grade thereof is one of 42.5 grade or 52.5 grade.
Further, the used ore powder is one of S95 grade ore powder or S105 grade ore powder.
Further, the fly ash is first-grade fly ash.
Furthermore, the specific surface area of the used silica fume is more than or equal to 20000m 2 Per kg, and the content of silicon dioxide is more than or equal to 90 percent.
Furthermore, the fineness of the used quartz sand is 20-50 meshes, the fineness of the used quartz powder is 120-200 meshes, and the fineness of the used limestone powder is 400 meshes.
Furthermore, the steel fiber is high-strength steel fiber with the tensile strength of more than or equal to 2500MPa, and can be selected from one or two of long straight shape and end hook shape for use, the length of the long straight steel fiber is 16-22 mm, the diameter of the long straight steel fiber is 0.18-0.25 mm, the length of the end hook shape steel fiber is 13-22 mm, and the diameter of the end hook shape steel fiber is 0.20-0.30 mm.
Further, the viscosity modifier used is hydroxypropyl methylcellulose ether, the viscosity number of which is 8000MPa · s or 40000MPa · s.
Furthermore, the water reducing agent is a polycarboxylic acid water reducing agent, the water reducing rate is not less than 25%, and the defoaming agent is an ether defoaming agent.
Further, the water used is tap water.
In the invention, the preparation process of the ultra-high performance concrete required by the preparation step 7 is as follows: weighing the raw materials according to a proportion, firstly premixing all the dry materials uniformly, then adding water or water mixed with a water reducing agent and a defoaming agent, mixing, adding the steel fiber when the mixture is in a uniform flow state, and continuously stirring until the mixture is uniform.
In the invention, the inner diameter of the material filling hose in the step 6 and the step 7 is 2-3 times of the length of the fiber in the ultra-high performance concrete.
In the invention, the maintenance operation of the step 8 is not less than 24h, and then the mould removing operation can be carried out.
In the invention, the damaged part of the concrete structure and the area within the range of 20cm above and below the damaged part are used as the area to be reinforced, and simultaneously, a high-pressure water gun is used for removing dirt and loose concrete on the surface of the area to be reinforced, so that the reinforcing effect is improved.
In the invention, the sludge and other impurities are removed from the upper surface of the foundation of the concrete structure to be reinforced, so that the surface of the foundation is smooth, the subsequent stable placement of a reinforcement cage and a template is ensured, and the pouring quality and the reinforcing effect are further ensured.
According to the invention, the reinforcement cage and the template are formed by two symmetrical structures according to the shape of the concrete structure to be reinforced, so that the installation of the reinforcement cage and the template is facilitated, and the distance between the reinforcement cage and the inner wall of the template is 20-30mm, so that the reinforcement cage is ensured to have a certain thickness of a reinforcement protection layer.
According to the method, the broken stones are poured into the gap between the template and the concrete structure to be reinforced in the sequence of pouring the broken stones firstly and then pouring the stone chips. The macadam adopts continuous gradation, the maximum grain diameter of the macadam does not exceed 1/3 of the reinforcing thickness, the purpose of the macadam is to ensure that the macadam can smoothly fall and be tightly stacked, the grain diameter range of the stone chips is 2-10mm, and the dumping thickness is 100-150mm, the purpose of the macadam is to form a stone chip layer which is tightly stacked above the macadam layer, and the purpose of ensuring that mortar does not leak when the underwater rapid hardening mortar is subsequently poured is ensured.
In the invention, the compressive strength of the selected underwater quick-hardening mortar reaches more than 10MPa after 3 hours of pouring, which aims to ensure the subsequent pouring of the ultrahigh-performance concrete and improve the reinforcing efficiency.
According to the invention, the ultra-high performance concrete with high tensile strain strengthening and underwater anti-dispersion characteristics is selected for reinforcing the underwater concrete structure, so that the integrity of the ultra-high performance concrete and the concrete structure to be reinforced is improved, and the defect that no bar planting operation is performed is overcome.
According to the invention, through reasonable design of the mixing proportion of the ultra-high performance concrete, the high tensile strain strengthening and underwater anti-dispersion characteristics of the ultra-high performance concrete are realized. In the design of the mixing proportion, the proportion of the cementing materials (cement, mineral powder, fly ash and silica fume) is reasonably optimized, so that the closest packing of the cementing material particles is realized, the good bonding strength between the hardened slurry and the steel fiber is ensured, and meanwhile, the type and the parameters of the steel fiber are reasonably selected, and the high tensile strain strengthening characteristic of the ultra-high performance concrete is ensured. And the hydroxypropyl methyl cellulose ether with the viscosity value of 8000MPa & s or 40000MPa & s is selected as the viscosity regulator, so that the underwater anti-dispersion capability of the ultra-high performance concrete can be obviously improved, and the mechanical property of the ultra-high performance concrete can not be obviously reduced.
In the invention, the inner diameter of the material filling hose for filling the underwater rapid-hardening mortar and the ultrahigh-performance concrete is 2-3 times of the length of the steel fiber in the ultrahigh-performance concrete, so that the smooth filling of the two materials is ensured.
In the invention, the ultra-high performance concrete can be demolded after being poured for at least 24 hours after being cured, and the specific curing time is determined according to the strength development condition of the ultra-high performance concrete. Generally, strength develops rapidly at higher ambient temperatures and slowly at lower ambient temperatures.
Compared with the existing underwater concrete structure maintenance and reinforcement method, the method has the following advantages:
1) The ultra-high performance concrete with the tensile hardening characteristic is selected to reinforce the concrete structure to be reinforced, so that the bar planting operation on the concrete structure to be reinforced is omitted, and the reinforcing method is simple and convenient;
2) The bonding performance of the ultrahigh-performance concrete and the concrete structure to be reinforced is good, and the reinforcing effect is ensured;
3) The ultra-high performance concrete has extremely high mechanical property and extremely low impermeability, thereby obviously improving the bearing capacity and durability of the reinforced structure.
Drawings
Fig. 1 is a schematic view of reinforcing an underwater concrete structure using ultra-high performance concrete. In the figure, 0 is water; 1 is an underwater concrete structure to be reinforced, and 1-1 is an area to be reinforced; 2, a foundation of a concrete structure to be reinforced; 3 is a reinforcement cage, 3-1 is a transverse reinforcement, and 3-2 is a longitudinal reinforcement; 4 is a template; 5 is a crushed stone layer; 6 is a stone chip layer; 7 is underwater rapid hardening mortar; 8 is ultra-high performance concrete; and 9 is a filling hose.
Fig. 2 is a front view of an ultra-high performance concrete axial tension test specimen structure.
Fig. 3 is a side view of fig. 2.
Fig. 4 is a top view of fig. 2.
FIG. 5 is a tensile stress-strain curve of the ultra-high performance concrete 28 obtained in example 1 over the d-age period.
FIG. 6 is a tensile stress-strain curve of the ultra-high performance concrete 28 obtained in example 2 over the d-age period.
FIG. 7 is a tensile stress-strain curve of the ultra-high performance concrete 28 obtained in example 3 over the d-age period.
Detailed Description
The method for reinforcing a submerged concrete structure using ultra-high performance concrete according to the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments, it being understood that the specific embodiments described herein are merely illustrative and not restrictive.
As shown in figure 1, a diver finishes the cleaning work of dirt and loose concrete on the surface of an area 1-1 to be reinforced, simultaneously, the surface of a foundation 2 of a concrete structure to be reinforced is cleaned to ensure that the surface of the foundation 2 is smooth, then a reinforcement cage 3 and a template 4 are respectively installed and placed on the surface of the foundation 2 of the concrete structure to be reinforced, graded broken stone is poured into a gap between the underwater concrete structure 1 to be reinforced and the template 4 to form a broken stone layer 5, the distance between the upper surface of the broken stone layer 5 and the lower part of the area 1-1 to be reinforced is 300-400 mm, and then stone chips are poured to form a stone chip layer 6, wherein the thickness of the stone chip layer is 100-150 mm. Pouring the underwater rapid-hardening mortar 7 through the pouring hose 9, wherein the port of the pouring hose 9 is positioned below the slurry level of the underwater rapid-hardening mortar 7, pouring the ultra-high performance concrete 8 continuously after the underwater rapid-hardening mortar 7 is poured for 3 hours, the port of the pouring hose 9 is positioned below the slurry level of the ultra-high performance concrete 8 and is not less than 200mm, curing is carried out for not less than 24 hours after the ultra-high performance concrete 8 is poured, and then the mold is removed. So far, the reinforcing work of reinforcing the underwater concrete structure by using the ultra-high performance concrete is completed.
In order to realize high tensile strain strengthening and underwater anti-dispersion properties of ultra-high performance concrete for reinforcing underwater concrete structures, the preparation of the ultra-high performance concrete can be illustrated by the following examples 1, 2 and 3.
Example 1, an ultrahigh-performance concrete for reinforcing an underwater concrete structure is prepared by weighing raw materials according to the weight ratio of cement (42.5-grade portland cement) 100, mineral powder (S105 grade) 25, fly ash 15, silica fume 15, quartz sand 55, quartz powder 36, limestone powder 25, steel fiber (end hook-shaped steel fiber with the length of 18mm and the diameter of 0.25 mm) 17.8, viscosity regulator (hydroxypropyl methyl cellulose ether with the viscosity value of 8000MPa · S) 0.06, water reducer (powder) 1.5, defoamer (powder) 0.2 and water 27, adding the cement, the mineral powder, the fly ash, the silica fume, the quartz sand, the quartz powder, the limestone powder, the viscosity regulator, the water reducer and the defoamer into a forced mixer for premixing and mixing, then adding water into a mixing kettle for one time and continuing to mix, adding the steel fiber into the mixture when the mixture is in a uniform flow state, and continuing to stir until the mixture is uniform, thereby obtaining the ultrahigh-performance concrete, and recording as U-1;
example 2, an ultrahigh-performance concrete for reinforcing an underwater concrete structure is prepared by weighing raw materials according to the weight ratio of cement (52.5-grade portland cement) 100, mineral powder (S95 grade) 40, fly ash 17, silica fume 32, quartz sand 75, quartz powder 50, limestone powder 30, steel fiber (long straight steel fiber with the length of 19mm and the diameter of 0.22 mm) 30.5, a viscosity regulator (hydroxypropyl methyl cellulose ether with the viscosity value of 8000MPa · S) 0.11, a water reducing agent (liquid) 2.0, a defoaming agent (liquid) 0.3 and water 36, adding the cement, the mineral powder, the fly ash, the silica fume, the quartz sand, the quartz powder, the limestone powder and the viscosity regulator into a forced mixer for premixing and mixing, adding water mixed with the water reducing agent and the defoaming agent into the mixer at a time, continuing to stir, adding the steel fiber into the mixture when the mixture is in a uniform flow state, continuing to stir the mixture until the mixture is uniform, and obtaining the ultrahigh-performance concrete, which is marked as U-2;
example 3, an ultra-high performance concrete for reinforcing an underwater concrete structure is prepared by mixing 100 parts of cement (52.5-grade Portland cement), 50 parts of mineral powder (S95 grade), 20 parts of fly ash, 40 parts of silica fume, 90 parts of quartz sand, 60 parts of quartz powder, 44 parts of limestone powder, 38.5 parts of steel fibers (long straight steel fibers with a length of 16mm, a diameter of 0.18mm, end hooked steel fibers with a length of 16mm and a diameter of 0.20 mm) in a weight ratio of 4:6), 0.16 parts of a viscosity modifier (hydroxypropyl methyl cellulose ether with a viscosity value of 40000MPa · S), 2.4 parts of a water reducer (liquid), 0.4 parts of a defoaming agent (liquid) and 39 parts of water in a weight ratio, pre-mixing the cement, the mineral powder, the fly ash, the silica fume, the quartz sand, the quartz powder, the limestone powder and the viscosity modifier in a forced mixer, adding the water mixed with the water reducer and the defoaming agent into the mixer at one time, continuously stirring the mixture, adding the steel fibers into the mixer when the mixture is in a fluid state, and continuously stirring the mixture to obtain a mixture, and uniformly stirring the mixture is U-3;
three ultrahigh-performance concretes obtained in examples 1 to 3 were subjected to the preparation of tensile test specimens, the shapes and dimensions of which are given in fig. 2 to 4, wherein R =62.5mm, a1=50mm, a2=25mm, a =100mm, b =100mm, h =500mm, h1=100mm, h2=150mm; the samples were subjected to standard maintenance and tensile property test on the 28 d-age samples to obtain tensile stress-strain curves of 3 groups of samples, which are respectively shown in fig. 5, 6 and 7, and the test results of the samples in the graphs were counted, and the results are shown in table 1.
Table 1 statistics of 28d age tensile test results for ultra-high performance concrete obtained in example
As can be seen from fig. 5, 6 and 7 in combination with table 1, the tensile stress-strain curves of the samples obtained in the three groups of examples all show obvious tensile hardening characteristics, and the strain strengthening index is high and the ultimate tensile strain is large. Therefore, the ultra-high performance concrete obtained by the embodiment of the invention has high tensile strain strengthening characteristics.
It should be noted that the application of the present invention is not limited to the above-mentioned examples, and that modifications and changes can be made by those skilled in the art according to the above-mentioned description, and all such modifications and changes are intended to fall within the scope of the appended claims.
Claims (6)
1. A method for reinforcing an underwater concrete structure by using ultra-high performance concrete is characterized by comprising the following steps:
step 1: cleaning the surface of a region to be reinforced;
and 2, step: cleaning a foundation of a concrete structure to be reinforced;
and step 3: placing a reinforcement cage, wherein the reinforcement cage is placed on the foundation of the concrete structure to be reinforced and at least covers the area to be reinforced;
and 4, step 4: installing a template, wherein the template is placed on the foundation of the concrete structure to be reinforced and is positioned outside the reinforcement cage;
and 5: pouring broken stones and stone chips into a gap between the template and the concrete structure to be reinforced;
step 6: pouring underwater rapid hardening mortar;
and 7: pouring the ultra-high performance concrete;
and 8: removing the mold after maintenance;
pouring broken stones into a gap between the template and the concrete structure to be reinforced according to the sequence of pouring the broken stones firstly and then pouring the stone chips, wherein the broken stones adopt continuous gradation, the maximum grain diameter cannot exceed 1/3 of the reinforcement thickness, the pouring amount is ensured to be 300 to 400mm away from the bottom of the area to be reinforced from the top of the broken stone layer, the grain diameter range of the stone chips is 2-10mm, and the pouring thickness is 100 to 150mm;
6, after the underwater rapid hardening mortar selected in the step 6 is poured for 3 hours, the compressive strength reaches more than 10MPa, a pouring port is kept below the surface of the underwater rapid hardening mortar slurry in the pouring process, and the pouring thickness is 200-250mm;
pouring the ultrahigh-performance concrete selected in the step 7 after the step 6 is finished for 3 hours, wherein a pouring opening is kept at a position which is more than or equal to 200mm below the surface of the ultrahigh-performance concrete slurry in the pouring process, and the ultrahigh-performance concrete selected in the step 7 has high tensile strain strengthening characteristics and good underwater anti-dispersion performance;
the raw material composition of the ultra-high performance concrete comprises: the cement, mineral powder, fly ash, silica fume, quartz sand, quartz powder, limestone powder, steel fiber, viscosity regulator, water reducing agent, defoaming agent and water, wherein the weight ratio of the raw materials is as follows:
cement 100
25-50 parts of mineral powder
15-20 parts of fly ash
15-40 parts of silica fume
55-90 parts of quartz sand
36-60 parts of quartz powder
Limestone powder 25-44
17.8-38.5 portions of steel fiber
0.06-0.16 viscosity regulator
1.1-2.4% of water reducing agent
Defoaming agent 0.2-0.4
26-39 parts of water.
2. The method as claimed in claim 1, wherein the region to be reinforced is a damaged portion of the concrete structure to be reinforced and a region 20cm above and below the damaged portion in the step 1, and a diver cleans the surface of the region to be reinforced with a high pressure water gun to remove dirt on the surface and loose concrete.
3. The method as claimed in claim 1, wherein the reinforcement cage of step 3 is formed by connecting two symmetrical structures by means of binding or welding according to the shape of the concrete structure to be reinforced, the reinforcement cage is formed by transverse reinforcement and longitudinal reinforcement, the transverse reinforcement is on the outside, and the reinforcement cage is placed on the foundation of the concrete structure to be reinforced.
4. The method for reinforcing an underwater concrete structure by using ultra-high performance concrete according to claim 1, wherein the form in step 4 is formed by fastening two symmetrical structures by bolts according to the shape of the concrete structure to be reinforced, the form is placed on the foundation of the concrete structure to be reinforced, and the distance between the inner wall of the form and the steel reinforcement cage is 20 to 30mm.
5. The method as claimed in claim 1, wherein the step 6 and step 7 are performed by using a hose, and the inner diameter of the hose is 2~3 times the length of the fiber in the ultra-high performance concrete.
6. The method for reinforcing a submerged concrete structure using ultra-high performance concrete according to claim 1, wherein the step 8 is characterized in that the ultra-high performance concrete is cured for not less than 24 hours after the completion of the pouring, and then the form removal is performed.
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| CN110924397A (en) * | 2019-12-11 | 2020-03-27 | 北京亚核通顺基础工程有限公司 | Coiled intelligent pile filling machine |
| TWI765776B (en) * | 2021-07-12 | 2022-05-21 | 李嘉峻 | Circular water injection cleaning and cofferdam construction methods |
| CN113482053B (en) * | 2021-07-12 | 2023-03-31 | 上海东华建设管理有限公司 | Caisson connecting section triangular area underwater concrete construction structure and construction method |
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| CN201771003U (en) * | 2010-07-08 | 2011-03-23 | 上海久坚加固工程有限公司 | Isolating body for reinforcing underwater piles |
| CN104831641A (en) * | 2015-05-19 | 2015-08-12 | 福州大学 | Bridge pier consolidation and restoration structure based on super-high-performance concrete and construction method thereof |
| CN108017345A (en) * | 2017-12-08 | 2018-05-11 | 江苏苏博特新材料股份有限公司 | A kind of ultrahigh-performance cement-based patching material and preparation method thereof |
| CN108222089A (en) * | 2018-02-08 | 2018-06-29 | 中交四航工程研究院有限公司 | A kind of underwater wet method prosthetic device of concrete-pile defect and restorative procedure |
| CN108425507B (en) * | 2018-03-21 | 2020-11-20 | 陕西建研结构工程股份有限公司 | Method for reinforcing concrete column by adopting UHPC |
| CN109265096A (en) * | 2018-08-22 | 2019-01-25 | 武大巨成结构股份有限公司 | A kind of ultrahigh-performance cement-based resistant abrasion material |
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