CN115838272A - Ultrahigh-density anti-neutron radiation concrete and construction method thereof - Google Patents
Ultrahigh-density anti-neutron radiation concrete and construction method thereof Download PDFInfo
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Abstract
The invention discloses an ultrahigh-density anti-neutron radiation concrete and a construction method thereof, wherein the radiation concrete is composed of cement, fly ash, magnetite sand, magnetite, water, an anti-cracking agent and a water reducing agent which are mixed in proportion; the construction method comprises the steps of mixing ice water at 0-5 ℃, and controlling the mold-entering temperature to be less than 30 ℃; adopting layered and segmented pouring; after pouring is completed, the side surface of the concrete is maintained by adopting a wood template with a mold, heat preservation cotton wool covers the outside of the template, the heat preservation maintenance time is not shorter than 14d, after the mold of the wall is removed, the surface of the concrete is wetted, then a water energy film is attached, and then geotextile covers the concrete for heat preservation, so that the effective control of the temperature reduction rate of the concrete is realized. Meanwhile, a wireless monitoring system is adopted to monitor temperature and deformation in real time, and real-time remote monitoring and early warning are carried out. The ultrahigh-density neutron radiation prevention concrete provided by the invention has higher density and cracking prevention performance, and is simpler and more convenient to construct.
Description
Technical Field
The invention belongs to the field of proton hospital construction, and particularly relates to ultrahigh-density anti-neutron radiation concrete and a construction method thereof.
Background
With the gradual improvement of the national medical system, currently, proton therapy has become the most advanced international cancer treatment technology, and with the maturity of proton therapy application, the construction of the domestic proton therapy center is rapidly developed. Because a special radiation field is generated in the proton treatment process, the radiation field is mainly a mixed radiation field of neutrons (accounting for about 80 percent) and gamma rays, and the nuclear radiation field brings great threat to human health and environment. The wall plate thickness is over 2m and the local thick large wall plate concrete density is not less than 39KN/m in the construction process of proton hospital 3 And the construction molding is required to have no through crack of more than or equal to 0.2 mm.
The conventional proton center radiation shielding design adopts a high steel plate with the thickness of 7 meters and the thickness of 50cm arranged in a large partition wall with the thickness of the proton center, and the radiation shielding design of the thick large sandwich steel plate wall has the advantages of high construction cost, complex construction process, heavy weight, inconvenient operation, long construction period, great potential safety hazard and unfavorable control on concrete cracks.
Disclosure of Invention
The invention is provided for overcoming the defects in the prior art, and aims to provide an ultrahigh-density anti-neutron radiation concrete and a construction method thereof.
In order to achieve the purpose, the invention adopts the following technical scheme:
the ultrahigh-density neutron radiation prevention concrete comprises the following components in percentage by mass of 1.5-2.2: 0.68-0.99: 9.03-15.15: 12.4-19.85: 1:0.19 to 0.31: 0.04-0.095 of cement, fly ash, magnetite sand, magnetite ore, water, anti-cracking agent and water reducing agent. The above ratio is preferably 2.2:0.99:15.15:19.85:1:0.31:0.095; the cement is medium and low heat portland cement or low heat slag portland cement. When portland cement or ordinary portland cement is used, a mineral admixture should be used.
In the technical scheme, the magnetite sand and the magnetite ore both have apparent density of more than 4800kg/m 3 The iron ore of (1).
In the technical scheme, the anti-cracking agent is HME-V, and the water reducing agent is PCA-I.
In the technical scheme, the density of the ultrahigh-density neutron radiation prevention concrete is more than 3900kg/m 3 。
A construction method of ultrahigh-density neutron radiation prevention concrete comprises the following steps:
premixing concrete, and controlling the mold-entering temperature of the concrete;
(ii) when pouring, according to the structural characteristics of the proton area, the thick large wall body is constructed in sections at the vertical elevation position of the proton area, and the thick building plate is poured in layers;
(iii) after pouring is finished, carrying out heat preservation maintenance on the side surface of the concrete with a mould; after the wall is demolded, heat preservation and moisture preservation maintenance are carried out, and the effective control of the concrete temperature reduction rate is realized.
In the technical scheme, the concrete mold-entering temperature control comprises the steps of cooling a concrete raw material, adding ice for mixing, preserving heat in the transportation process and selecting reasonable pouring time; the concrete mold-entering temperature is controlled to be less than 30 ℃.
In the above technical scheme, when pouring is performed in step (ii), the reinforcing steel bar heads and the vibrating rod bodies are connected and lengthened in a welding manner for the dense pipeline parts in the dense concrete wall body in the mass sub-area, through vibration transmission, it is ensured that concrete at different gap parts between the dense pipelines is vibrated compactly when concrete is poured on the wall body, and the vibration time of the concrete is preferably controlled within 20 s-30 s.
In the technical scheme, the time for maintaining the heat preservation of the mould is not less than 14d, the concrete method for maintaining the heat preservation of the mould is that the side surface of the concrete is maintained by adopting a wood template with the mould, and heat preservation cotton wool covers the outside of the template; when the wall is demolded, the difference between the central temperature of the concrete and the ambient temperature is not higher than 15 ℃; the heat preservation and moisture preservation maintaining time is not less than 7 days, and the specific method comprises the following steps: after the wall is demoulded, the surface of the concrete is wetted and then is attached with a water energy film, and then the concrete is covered with geotextile for heat preservation.
In the technical scheme, the construction method of the ultrahigh-density anti-neutron radiation concrete is applied to the construction of mass concrete of a radiation-proof heavy-density concrete thick and large wall body in a proton area, and a wireless monitoring system is adopted to monitor temperature and deformation in real time and perform real-time remote monitoring and early warning during construction; and a cracking risk early warning program is set, the timely adjustment and optimization of on-site heat preservation maintenance measures are guided, and the refined and intelligent construction is guided.
In the above technical solution, before the pouring, the field organization 1:1, constructing a test section, drilling a core and sampling, and detecting the element components and the density of the poured and molded heavy-density concrete.
The invention has the beneficial effects that:
the invention provides an ultrahigh-density anti-neutron radiation concrete and a construction method thereof, wherein magnetite is selected as coarse and fine aggregate to prepare the concrete with the density of 3900kg/m 3 The radiation-proof concrete is based on the crack resistance evaluation and design of mass concrete under the multi-field coupling effect, and the guarantee rate of preventing the proton center radiation-proof mass concrete from cracking is controlled to be more than or equal to 95 percent; meanwhile, the effect of the construction process measures on the anti-cracking performance of the concrete is evaluated, a targeted proton center mass concrete crack control construction method is provided through research, and the non-penetrating shrinkage crack of the proton center main body structure concrete is realized.
Drawings
FIG. 1 is a sidewall crack risk calculation model (a, a solid model; b, a grid model) in embodiment 2 of the present invention;
FIG. 2 is a model (a. Solid model; b. Mesh model) for calculating the risk of cracking of the floor in example 2 of the present invention;
FIG. 3 shows the results of the benchmark, the temperature history of the anti-cracking concrete and the cracking risk coefficient (a. Temperature history; b. Interior temperature difference c. Internal cracking risk d. Surface cracking risk) at the 30 ℃ mold-entering temperature of the base plate concrete in the embodiment 2 of the invention;
FIG. 4 shows the results of the benchmark, the temperature history of the anti-cracking concrete and the cracking risk coefficient (a, the temperature history, b, the temperature difference between the inside and the outside, c, the internal cracking risk, d, the surface cracking risk) at the mold-entry temperature of 30 ℃ in the summer construction of the heavy concrete side wall in example 2 of the present invention.
For a person skilled in the art, other relevant figures can be obtained from the above figures without inventive effort.
Detailed Description
In order to make the technical solutions of the present invention better understood by those skilled in the art, the technical solutions of the present invention are further described below by way of specific embodiments with reference to the drawings of the specification.
Example 1
An ultrahigh-density anti-neutron radiation concrete, which comprises the following components in a mass ratio of 2.2:0.99:15.15:19.85:1:0.31:0.095 of blended cement, fly ash, magnetite sand, magnetite ore, water, anti-cracking agent HME-V and water reducing agent PCA-I. The magnetite sand and the magnetite ore both have apparent density of more than 4800kg/m 3 The iron ore of (1).
The specific types and the quality of each component in the embodiment are as follows:
the density of the ultrahigh-density neutron radiation prevention concrete is more than 3900kg/m 3 And no through crack larger than or equal to 0.2mm is generated after the casting is finished in high-temperature weather in summer.
According to the invention, based on the crack resistance evaluation and design of mass concrete under the multi-field coupling effect, magnetite is adopted as a radiation-proof material, and a polycarboxylic acid high-performance water reducing agent with a low shrinkage ratio and a high-efficiency crack resistance agent with the functions of temperature rise inhibition and micro-expansion are doped; the water reducing agent does not increase shrinkage, the expansion process regulation and control of the anti-cracking agent mainly utilizes expansion components (calcium oxide (28%) and magnesium oxide (54%) with different expansion characteristics to realize staged and overall process compensation shrinkage, and the heavy concrete is ensured to have a crack risk value of more than 95% in the concrete configuration stage through the cement hydration process regulation and control and calcium-magnesium multi-element composite expansion compensation shrinkage.
Example 2
A construction process of ultrahigh-density neutron radiation prevention concrete comprises the following steps:
(I) preliminary evaluation and Material screening
Environmental assessment and sanitation assessment radiation assessment:
performing radiation field modeling analysis on the proton center, simulating the operation radiation field environment of equipment, performing simulation analysis on the structural form, the wall thickness and the radiation-proof concrete material, and determining the structural form, the wall arrangement, the wall thickness and the radiation material of a proton area;
(ii) radiant material screening:
adopting the forward preparation principle to carry out element and performance measurement on various radiation materials, confirming the material types of coarse aggregate and fine aggregate, and ensuring that the apparent density of high-quality magnetite ore is more than 4800kg/m 3 The apparent density of the C30 concrete prepared by adopting the aggregate can reach 3900kg/m 3 The concrete has the advantages of good shielding effect on proton radiation, X rays and gamma rays, good radiation resistance of a concrete structure and good control on the crack resistance of concrete.
(iii) mix proportion design index optimization:
on the basis of meeting the working performance, mechanical performance, durability and crack resistance of concrete, the mixing proportion of the concrete as shown in the component table in example 1 is determined according to multiple trial-and-error tests, magnetite ore is used as coarse aggregate, and tests on the working performance and the mechanical performance are respectively verified according to the mixing proportion.
(iv) evaluation of crack Risk of Mass concrete in proton region
A multi-field coupling shrinkage cracking assessment model is adopted, the multi-field coupling shrinkage cracking assessment model mainly comprises a bottom plate, a wall body and a top plate, the evolution rules of a concrete temperature field and a concrete humidity field are simulated and analyzed by combining the structure size, the constraint condition and the construction process, and the shrinkage cracking risk of the structural concrete is further analyzed based on a stress criterion.
The sidewall and bottom plate calculation models in this embodiment are shown in fig. 1 and 2.
The common concrete side wall is 1.95m (about 44.6m long), 3.2m (about 17.8m long) and 3.9m (about 11m long), the heavy concrete side wall is 3.4m (about 16.4m long), the bottom plate is 30m wide and 62m long.
The results of the benchmark and anti-crack concrete temperature history and cracking risk coefficient at the mold-entering temperature of 30 ℃ in the floor concrete summer construction are shown in fig. 3. As can be seen from the figure, the maximum temperature rise of the center of the bottom plate concrete is about 30.4 ℃, and the maximum temperature difference between the inside and the outside is about 4.5 ℃; when the mold-entering temperature is reduced to 30 ℃, the maximum cracking risk of the surface and the interior of the base plate reference concrete is still larger than 1.0, the base plate reference concrete is inevitably cracked, and after the base plate reference concrete is added with crack resistance, the maximum cracking risk coefficient is further reduced to be below 0.5, so that the control requirement is met.
The results of the benchmark and anti-crack concrete temperature history and the crack risk coefficient at the mold-in temperature of 30 ℃ in summer construction of the heavy concrete side wall with the thickness of 3.6m are shown in FIG. 4. As can be seen from the figure, when the mold-entering temperature is reduced to 30 ℃, the maximum temperature rise of the center of the heavy concrete of the side wall is about 26.7 ℃, and the maximum temperature difference between the inside and the outside is about 11.4 ℃; the maximum cracking risk coefficient in the side wall reference heavy concrete is greater than 0.7, the possibility of cracking is high, the surface cracking risk is less than 0.7, the control requirement is met, and after the anti-cracking agent is added, the maximum cracking risk is reduced to be less than 0.5, and the control requirement is met.
(v) verification of test section:
before formal construction, simulating a site entity pouring working condition, verifying whether the density and the radiation performance of heavy-density concrete meet requirements, verifying the construction performance and the mechanical performance rule of the overweight-density concrete, verifying pilot production actual parameters of the overweight-density concrete and distinguishing connection with laboratory preparation performance, verifying a pipeline positioning and installing construction method, a dense pipeline and reinforcing steel bar binding and inserting construction method, a template reinforcing form and the like in an ultra-thick wall, monitoring temperature rise and strain change after concrete pouring, a concrete curing mode, forming quality and the like after pouring, meanwhile, verifying the design rationality, selecting a T-field wall body at the intersection part of the most complex pipeline, the heavy concrete and the common concrete in a project, and constructing 1: and 1, carrying out a simulation test in a test section, and successfully pouring through the test section to provide test parameters for the successful construction of subsequent entity engineering.
(II) construction process
(vi) construction of heavy density concrete:
(a) Concrete in-mold temperature control
The concrete mold-entering temperature control comprises the steps of cooling of concrete raw materials, mixing with ice, heat preservation in the transportation process and reasonable pouring time selection.
(1) Planning and arranging the construction progress in advance, selecting reasonable pouring time, such as 20-00 days to 8 days every day;
(2) Aggregate is put into a warehouse and stored in advance, and on the basis of the sandstone sunshade, water spraying or mist spraying is carried out on the sandstone in the material yard by adopting a water spraying or mist spraying machine if necessary, and the temperature is reduced for 2 to 3 times every day;
(3) Controlling the approach temperature of powder, controlling the approach temperature of cement to be less than or equal to 60 ℃, and controlling the temperature of fly ash to be less than or equal to 40 ℃;
(4) Deep well water is used as mixing water, or block ice is added into the mixing water, the ice adding amount is determined according to the requirement of mold-entering temperature, and when the temperature of 20 ℃ per ton of water is reduced to 0-5 ℃, at least 1.5 tons of ice at minus 10 ℃ are needed;
when heavy-density concrete is premixed in high-temperature weather in summer, mixing with ice water at 0-5 ℃, and controlling the mold-entering temperature to be less than 30 ℃;
(5) Wrapping the concrete transportation tank car with heat insulation cloth;
(6) A dispatcher is arranged on a construction site, the unloading order of the tank trucks on two sides and whether the mixing station is used for mixing or not are allocated according to the pouring condition, the temperature rise of concrete caused by the overlong stay time of the tank trucks on the site is avoided, and the transportation and waiting time is less than or equal to 1h;
(7) Arranging sunshade in waiting areas of the pump truck and the tank truck;
(8) Because the temperature of the steel bars and the pipelines is greatly increased by illumination in the daytime, the concrete bin surface, particularly the steel bars and the pipelines, is sprayed and cooled before pouring, but obvious water accumulation at the bottom is avoided;
(9) The formwork supporting system of the heavy-density concrete thick large wall adopts 18mm covered black formworks, the vertical back ridges adopt 50X 2mm rectangular steel pipes, and the transverse back ridges are reinforced by double-groove steel.
(b) Concrete pouring and vibrating quality control
(1) And when pouring, according to the structural characteristics of the proton area, the thick and large wall body is constructed in sections at the vertical elevation position of the proton area.
The concrete pouring adopts layered and segmented pouring, the height of the largest section of wall body is 3m, during layering, a rabbet is reserved, the height of the rabbet is 200mm, the width of the rabbet is 1/3 of the wall thickness, and before new concrete pouring, the rabbet position is chiseled;
(2) In the pouring process, longitudinal construction joints are not reserved as far as possible, for concrete junction positions with different properties, steel wire meshes are adopted for intercepting, the steel wire meshes are reserved in rabbet shapes, concrete with different properties is synchronously poured, and the pouring surface of heavy concrete is always kept higher than other concrete pouring surfaces by 30-40cm.
(3) The thick large floor with the thickness exceeding 2m is poured in a layered mode, and the problem that the supporting frame body cannot be constructed or the supporting frame body needs to be designed additionally due to the fact that the space between the supporting frame bodies is too dense and the supporting frame body cannot be constructed due to the fact that the single construction thickness of the floor is too thick is solved. When the floor slabs are poured in a layered mode, the supporting system is supported by the disc buckling frames, the distance between the vertical rods is 0.3 x 0.6m, the step pitch is 1.2m, the layered thickness of the plate surface is not more than 1.4m, when the plate surface is poured in a layered mode, the second layer of concrete is poured after the first layer of concrete poured reaches 50% of the design strength, and the second layer of concrete is poured. Before the second layer of concrete is poured, the previous layer of concrete needs to be chiseled, so that the bonding force of the new and old concrete poured on the plate surface between the two layers of concrete in a layered mode is strong, and the integrity of a concrete wall body is effectively guaranteed;
(4) Intensive pipeline position adopts the rod-like head of reinforcing bar and the excellent body of the vibrating rod to be connected and connects long to the weight density concrete wall in the matter subregion, through the transmission of vibrating, guarantees when wall body concrete placement, and different clearance position concrete between the intensive pipeline vibrates closely knit, avoids because pipeline vibration that the vibrating rod amplitude is too big to cause shifts or the vibration is destroyed.
The concrete vibration time is preferably controlled within 20-30 s, so that the quick insertion and the slow pulling are realized, and the leakage vibration and the over vibration are avoided. To intensive pipeline position, can't adopt conventional vibrating rod to vibrate, connect long through the vibrating rod barred body to through stress transfer, guarantee that the concrete at intensive pipeline position vibrates closely knit.
(c) Stripping and curing concrete
And after pouring is finished, the side surface of the concrete is maintained by adopting a wood template with a mold, heat-preservation cotton wool covers the outside of the template, and the heat-preservation maintenance time is not shorter than 14d.
The difference between the central temperature of the concrete and the ambient temperature during the form removal is not higher than 15 ℃; the method is suitable for removing the formwork when the ambient temperature is high in daytime, after the formwork is removed from the wall, the surface of the concrete is wetted, then the water energy film is attached to the concrete for moisture preservation and maintenance, then the geotextile is covered for heat preservation, the maintenance time is not less than 7 days, and the effective control of the concrete temperature reduction rate is realized. When the temperature suddenly drops during the curing of the strip mold, a heat insulation material is covered outside the template if necessary according to the monitoring result, and the curing time is determined according to the temperature monitoring result.
(d) Concrete monitoring
The method comprises the following steps that (1) the radiation-proof heavy-density concrete thick and large wall body and large-volume concrete in a proton area are subjected to real-time temperature and deformation monitoring, real-time remote monitoring and early warning by a wireless monitoring system; and a cracking risk early warning program is set, timely adjustment and optimization of field heat preservation maintenance measures and the like are guided, and refined and intelligent construction is guided.
(vii) acceptance
After the ultrahigh-density neutron radiation-proof concrete is developed and before concrete construction, element components of the heavy-density concrete are detected, and the element content is ensured to meet the requirements of environmental assessment reports. Meanwhile, the test block is weighed to ensure that the dry density of the heavy-density concrete is more than or equal to 3900kg/m 3 . Before formal construction, organizing 1:1, constructing a test section, drilling a core and sampling, and detecting the element components and the density of the poured and molded heavy-density concrete. At the same time, simulating proton central radiation fieldAnd performing a radiation shielding detection test to verify that the radiation shielding performance of the ultrahigh-density neutron radiation prevention concrete meets the operation and use requirements of proton equipment. And finally, organizing heavy density concrete construction, detecting the forming quality and crack control condition of the radiation-proof heavy density concrete thick and large wall body, and not allowing a through crack larger than or equal to 0.2mm to appear on the radiation-proof thick and large wall body after the formwork is removed.
Compared with the prior art, the invention has the following advantages:
(1) By researching ultra-high density radiation protection preparation and construction, the proportion of coarse aggregate and fine aggregate is reasonably selected, the physical and radiation shielding performance of concrete is improved, the on-site ultra-high density radiation protection concrete construction technology is optimized, the manufacturing cost of concrete is reduced, and the construction period and the construction cost can be shortened by 50%.
(2) By adopting the invention to carry out proton center radiation shielding construction, the construction is simple, convenient, safe and reliable, and the safety risk of the installation of the thick and large sandwich steel plate wall is reduced.
(3) The thick building plate is poured in layers, so that the problem that the supporting frame body cannot be constructed or the supporting frame body needs to be additionally designed due to too close spacing of the supporting frame bodies caused by too thick single construction thickness of the floor slab is solved.
(4) The problem of cracking of the radiation-proof shielding wall body in the proton center is solved, the integral construction radiation-proof performance of the proton center is ensured, and the construction quality is improved.
(5) The method can be widely applied to the design and construction of various proton center radiation shielding walls, and the large-volume concrete crack-resistant design and construction method embodied by the invention are particularly suitable for the construction of ultra-large-volume concrete.
The invention provides an ultrahigh-density neutron radiation prevention concrete and a construction method thereof, which can meet the special requirements of a proton treatment radiation shielding place and are widely applied to the construction of a proton center. On the basis of basic determination of the structure size and the constraint condition, the invention adopts the measures of combining materials and construction process measures, firstly reduces the cracking risk through the performance optimization of the concrete material, and simultaneously adopts the measures of construction process optimization, functional materials and the like.
The ultra-high density of the inventionThe apparent density of the concrete for preventing neutron radiation is more than 4800kg/m 3 The magnetite/stone is used as coarse and fine aggregate to prepare the radiation-proof concrete, the integral radiation-proof performance of the structure is ensured, and the apparent density of the prepared C30 concrete can reach 3900kg/m 3 The material has good shielding effect on proton radiation, X rays and gamma rays; the construction method for controlling the cracks of the mass concrete with the proton center determines the crack resistance control index of the concrete, controls the shrinkage crack risk coefficient of the mass concrete with the proton center main body structure to be less than or equal to 0.7, ensures the crack prevention rate to be more than or equal to 95 percent, and ensures the effect of the crack resistance of the concrete by the construction process measures.
It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.
The applicant declares that the above description is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and it should be understood by those skilled in the art that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are within the scope and disclosure of the present invention.
Claims (10)
1. The utility model provides an ultrahigh density prevents neutron radiation concrete which characterized in that: the concrete comprises the following components in percentage by mass of 1.5-2.2: 0.68-0.99: 9.03-15.15: 12.4-19.85: 1:0.19 to 0.31: 0.04-0.095 of cement, fly ash, magnetite sand, magnetite ore, water, an anti-cracking agent and a water reducing agent.
2. The ultra-high density anti-neutron radiation concrete according to claim 1, wherein: the magnetite sand and the magnetite ore both have apparent density of more than 4800kg/m 3 The iron ore of (1).
3. The ultra-high density anti-neutron radiation concrete according to claim 1, wherein: the anti-cracking agent is HME-V, and the water reducing agent is PCA-I.
4. The ultra-high density anti-neutron radiation concrete according to claim 1, wherein: the density of the ultrahigh-density neutron radiation prevention concrete is more than 3900kg/m 3 。
5. A construction method of ultrahigh-density neutron radiation prevention concrete is characterized by comprising the following steps: the method comprises the following steps:
premixing concrete, and controlling the mold-entering temperature of the concrete;
(ii) when pouring, according to the structural characteristics of the proton area, the thick large wall body is constructed in sections at the vertical elevation position of the proton area, and the thick building plate is poured in layers;
(iii) after pouring is finished, carrying out heat preservation maintenance on the side surface of the concrete with a mould; after the wall is demolded, heat preservation and moisture preservation maintenance are carried out, and the effective control of the concrete temperature reduction rate is realized.
6. The construction method of the ultra-high density neutron radiation prevention concrete according to claim 1, characterized in that: the concrete mold-entering temperature control comprises the steps of cooling of concrete raw materials, mixing with ice, heat preservation in the transportation process and reasonable pouring time selection; the concrete mold-entering temperature is controlled to be less than 30 ℃.
7. The construction method of the ultra-high density anti-neutron radiation concrete according to claim 1, characterized in that: and (ii) when pouring, connecting and lengthening the dense pipeline parts in the dense concrete wall in the mass sub-area by adopting a steel bar head and a vibrating rod body in a welding mode, and ensuring that concrete in different gap parts among the dense pipelines is vibrated compactly when pouring the concrete in the wall through vibration transmission, wherein the vibration time of the concrete is preferably controlled within 20 s-30 s.
8. The construction method of the ultra-high density anti-neutron radiation concrete according to claim 1, characterized in that: the time of the heat preservation and maintenance of the belt mold is not less than 14d, the concrete method of the heat preservation and maintenance of the belt mold is that the concrete side surface is maintained by the wood template belt mold, and the outside of the template is covered with heat preservation cotton wool; when the wall is demolded, the difference between the central temperature of the concrete and the ambient temperature is not higher than 15 ℃; the heat preservation and moisture preservation maintaining time is not less than 7 days, and the specific method comprises the following steps: after the wall is demoulded, the surface of the concrete is wetted and then is attached with a water energy film, and then the concrete is covered with geotextile for heat preservation.
9. The construction method of the ultra-high density anti-neutron radiation concrete according to claim 1, characterized in that: the construction method of the ultrahigh-density anti-neutron radiation concrete is applied to the construction of the large-volume concrete of the anti-radiation heavy-density concrete thick and large wall body in the texture area, and a wireless monitoring system is adopted to monitor the temperature and the deformation in real time and remotely monitor and early warn in real time during construction; and a cracking risk early warning program is set, the timely adjustment and optimization of on-site heat preservation maintenance measures are guided, and the refined and intelligent construction is guided.
10. The construction method of the ultra-high density anti-neutron radiation concrete according to claim 1, characterized in that: before the pouring is carried out, the field organization is 1:1, constructing a test section, drilling a core and sampling, and detecting the element components and the density of the poured and molded heavy-density concrete.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114702279A (en) * | 2022-03-29 | 2022-07-05 | 武汉明华鸿昌新型建材有限责任公司 | Heavy-density radiation-proof concrete for protecting proton center in hospital and preparation method thereof |
| CN114750282A (en) * | 2022-03-22 | 2022-07-15 | 中建三局集团有限公司 | Radiation cracking resistant large-volume heavy concrete and preparation method and construction method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114750282A (en) * | 2022-03-22 | 2022-07-15 | 中建三局集团有限公司 | Radiation cracking resistant large-volume heavy concrete and preparation method and construction method thereof |
| CN114702279A (en) * | 2022-03-29 | 2022-07-05 | 武汉明华鸿昌新型建材有限责任公司 | Heavy-density radiation-proof concrete for protecting proton center in hospital and preparation method thereof |
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| Title |
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| 蔚建华主编: ""建筑工程施工组织设计编制与案例精选 土木工程施工组织设计"", vol. 1, 中国地质大学出版社, pages: 250 - 251 * |
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