CN112759315B - Construction method for dynamically controlling VC value of roller compacted concrete under complex weather condition - Google Patents

Construction method for dynamically controlling VC value of roller compacted concrete under complex weather condition Download PDF

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CN112759315B
CN112759315B CN202011520484.4A CN202011520484A CN112759315B CN 112759315 B CN112759315 B CN 112759315B CN 202011520484 A CN202011520484 A CN 202011520484A CN 112759315 B CN112759315 B CN 112759315B
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roller compacted
value
compacted concrete
concrete
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CN112759315A (en
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路明
向前
周兴朝
熊涛
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Sinohydro Bureau 9 Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D15/00—Handling building or like materials for hydraulic engineering or foundations
    • E02D15/02—Handling of bulk concrete specially for foundation or hydraulic engineering purposes
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D7/00—Methods or apparatus for placing sheet pile bulkheads, piles, mouldpipes, or other moulds
    • E02D7/02—Placing by driving
    • E02D7/06—Power-driven drivers
    • E02D7/08—Drop drivers with free-falling hammer
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/00991—Uses not provided for elsewhere in C04B2111/00 for testing
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/76—Use at unusual temperatures, e.g. sub-zero
    • 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 a construction method for dynamically controlling a VC (compressed concrete) value of rolled concrete under a complex climate condition, which comprises the steps of raw material detection, VC value and unit water consumption determination, rolled concrete production and machine outlet detection, rolled concrete on-site detection, pouring and correction. The process is suitable for the complex and changeable single-day climate environment, and the VC value of the roller compacted concrete can be dynamically controlled according to the climate environment conditions, so that the roller compacted concrete can adapt to the change of the climate environment, and the stability of the workability, the workability and the grindability of the roller compacted concrete is ensured; the method effectively ensures various performances and engineering quality of the roller compacted concrete, ensures the pouring speed and efficacy of the roller compacted concrete due to the stable and good workability and workability of the roller compacted concrete, and solves the problem of accurately and dynamically controlling the VC value of the roller compacted concrete in the complex climate environment of the Qinghai-Tibet plateau.

Description

Construction method for dynamically controlling VC value of roller compacted concrete under complex weather condition
Technical Field
The invention belongs to the technical field of building construction, and particularly relates to a construction method for dynamically controlling the VC value of roller compacted concrete under a complex climate condition.
Background
The roller compacted concrete is dry and hard poor cement concrete without slump, has the characteristics of small concrete volume, high strength, good seepage-proofing performance, overflow of a dam body and the like, has the advantages of simple, quick and economic construction procedures of an earth-rock dam and the use of large-scale general machinery, and is widely applied to various hydraulic and hydroelectric engineering. In the process of controlling the production of the roller compacted concrete, the VC value is taken as an extremely important control index, and directly influences various performances of interlayer combination, compressive strength, frost resistance, impermeability and the like of the roller compacted concrete. In many roller compacted concrete projects in inland countries, the VC value of the roller compacted concrete needs to be properly adjusted according to the change of climate conditions, but because the change of the inland climate is single and relatively stable, the control of the VC value is relatively simple, for example, when the rainfall (light rain (1-3 mm/h)) appears on the storehouse surface, the VC value of the roller compacted concrete is properly compensated according to the rainfall, and only the VC value needs to be adjusted in seasons when the seasons change.
The DG hydropower station dam is a roller compacted concrete gravity dam with the highest altitude in China at present, the climate of the area where the DG hydropower station dam is located belongs to the plateau temperate zone monsoon and semi-humid climate, the dry season is 11 months to 4 months in the next year, and the rainy season is 5 months to 10 months. The average temperature of a meteorological station (about 35km at the downstream of a dam site and 3260m in height of the meteorological station) for many years is 9.3 ℃, the extreme highest temperature and the extreme lowest temperature are 32.5 ℃ and-16.6 ℃ respectively, the average relative humidity for many years is 51 percent, and the measured temperature of the DG hydropower station cabin surface is as shown in the following table 1.
Table 1DG hydropower station storehouse surface actual measurement temperature statistical table
Figure GDA0003933776660000011
Figure GDA0003933776660000021
Although relatively mature roller compacted concrete construction and quality control experience exists in inland countries, and roller compacted concrete quality control experience in some cold regions can be used as reference, the engineering experience in other regions cannot be completely used as reference for the DG hydropower station dam in the Tibet because of the complex weather conditions of 'four seasons of the day' such as strong sunshine, large day and night temperature difference, large evaporation capacity, large humidity change and the like which are specific to the high-altitude regions in the Tibet. In order to ensure various performances and engineering quality of the roller compacted concrete of the Tibet DG hydropower station and reduce the maintenance cost of a dam in the later period, the development of a construction method for dynamically controlling the VC value of the roller compacted concrete under the complicated weather condition is particularly important.
Disclosure of Invention
The invention provides a construction method for dynamically controlling the VC value of roller compacted concrete under complex weather conditions to solve the technical problems.
In order to achieve the above purpose, the invention adopts the following technical scheme:
a construction method for dynamically controlling VC value of roller compacted concrete under complex climate conditions comprises the following steps:
(1) Raw material detection: detecting cement, fly ash, a water reducing agent, an air entraining agent, coarse aggregate, fine aggregate and mixing water for producing roller compacted concrete according to specific detection indexes and detection frequency;
(2) Determination of VC value and unit water consumption: determining VC values when the compaction thickness, the apparent density and the slurry flooding effect are met under different temperature and humidity conditions according to field detection, and establishing a unitary regression relation curve y of the bin surface air temperature and the VC values under different humidity conditions 1 、y 2 、y 3 Selecting corresponding unitary regression relation curve to calculate VC value suitable for construction under the storehouse surface climate condition according to the storehouse surface climate environment in the production process, and establishing unitary regression relation curve y of unit water consumption and VC value 4 ；
(3) Roller compacted concrete production and machine outlet detection: feeding the raw materials into a concrete mixer, uniformly mixing, and detecting the mixing performance of the VC value, the gas content and the setting time of a roller compacted concrete outlet to see whether the mixing performance meets the requirements;
(4) And (3) field detection of roller compacted concrete: detecting the mixing performance of the on-site VC value, the air content and the setting time of the roller compacted concrete qualified by the machine outlet detection to see whether the mixing performance meets the requirements or not;
(5) Pouring and correcting: casting the roller compacted concrete qualified by detection on site, detecting the compactness of the roller compacted concrete, simultaneously recording VC (vitamin C) value, air temperature and humidity data, and utilizing real-time data to carry out regression on the unitary regression relation curve y 1 、y 2 、y 3 、y 4 Making corrections and guiding field production.
Further, in the step (1), the fine aggregate is detected for fineness modulus, stone powder content, particle content, water content and methylene blue MB value, wherein the fineness modulus, the stone powder content, the particle content and the methylene blue MB value are detected once every day, and the water content is detected for 1 time every 2 h.
Further, in the step (1), the coarse aggregate is detected with the excess diameter content, the content of the son diameter, the content of the medium diameter surplus sieve, the mud content and the water content of the small stones, wherein the excess diameter content, the content of the son diameter, the content of the medium diameter surplus sieve and the mud content are detected every 8 times, and the water content is detected every 2 hours; the preparation concentration of the solution is detected every 8 times.
Further, in step (2), the univariate regression relationship curve y 1 ＝-0.0493X 1 +2.7(R 2 VC value univariate regression relation curve with humidity of 10-20% = 0.9952); y is 2 ＝-0.0621X 2 +3.2571(R 2 VC value unary regression relation curve with humidity of 20-40% = 0.998); y is 3 ＝-0.0621X 3 +3.5571(R 2 VC value unary regression relation curve with humidity of 40-60% and = 0.998); y is 4 ＝-0.3317X 4 +30.227(R 2 = 0.994). Said X is 1 、X 2 、X 3 Respectively representing the temperature of the cabin surface when the humidity is 10-20%, 20-40% and 40-60%; x 4 Representing the unit water usage.
And further, in the step (3), if the roller compacted concrete is qualified in outlet detection, the next procedure is performed, if the roller compacted concrete is unqualified in outlet detection, the waste treatment procedure is performed, the batching procedure is performed, and the raw material ratio is readjusted.
And (5) in the step (4), if the roller compacted concrete is qualified in field detection, entering the next procedure, if the roller compacted concrete is unqualified in field detection, entering a waste treatment procedure, returning to a batching procedure, and readjusting the mixture ratio of the raw materials.
Further, in the step (5), the compaction degree of the roller compacted concrete meets the conditions that the compaction degree of the third-level mixed roller compacted concrete is more than or equal to 97 percent and the compaction degree of the second-level mixed roller compacted concrete is more than or equal to 98 percent.
Further, when strong wind or rainfall occurs on the surface of the bin, the VC value of the roller compacted concrete is compensated according to the strong wind level and the rainfall.
Further, the rain speed of the rainfall is 1-3 mm/h.
All the detection quality deteriorations of the cement accord with the requirements of moderate heat portland cement, low heat portland cement and low heat slag portland cement (GB/T200-2017); technical Specifications for blending fly ash into hydraulic concrete (DL/T5055-2007); technical specification of admixture for hydraulic concrete (DL/T5100-2014); water quality analysis test protocol for Hydraulic concrete (DL/T5152-2017); specification for Hydraulic concrete construction (DL/T5144-2015); technical Specifications for durability of Hydraulic concrete (DL/T5241-2010); specification of Hydraulic roller compacted concrete construction (DL/T5112-2009); part 8 of the evaluation standard of the unit engineering quality level of the hydropower and water conservancy basic construction engineering: hydraulic roller compacted concrete engineering (DL/T5113.8-2012),
the raw materials are used, and the cement production company is Huaxin cement company, and the model/grade is P.MH 42.5; the fly ash production company is Ningxia Jinxin environmental protection science and technology limited company, and the model/grade is II grade; the water reducing agent is GK-4A/high-efficiency water reducing agent (retarding type) of Shijiazhuang cichang Yongyuen building materials Co., ltd, or HT-5/high-efficiency water reducing agent (retarding type) of Shanxi Hengtai Weiyuen building materials Co., ltd; the air entraining agent is GK-9A/air entraining agent of Shijiazhuang cichangnyu building materials Co., ltd, or HT-11/air entraining agent of Shanxi Hengtai Weiyu building materials Co., ltd; the coarse aggregate production company is a DG hydropower station nine-part sandstone system, and the type/grade is artificial macadam; the fine aggregate production company is a DG hydropower station nine-part sand and stone system, and the model/grade is artificial sand; the mixing water production company is a DG hydropower station nine-office sand-stone system, and the model/grade is drinking water.
By dynamically controlling the VC value of the roller compacted concrete, when the roller compacted concrete is vibrated and rolled for 2-3 times in the construction process, the surface is grouted to form a thin slurry layer and the slurry layer has slight elasticity, and simultaneously, the upper layer is paved and rolled before the concrete is initially set, so that the slurry and aggregate can be embedded into the lower layer concrete when the upper layer concrete is rolled and vibrated, and the upper layer concrete and the lower layer concrete are mutually penetrated and staggered to form a whole body so as to ensure good interlayer combination; meanwhile, a nuclear density meter is used for detecting the compaction degree of the roller compacted concrete, and the compaction degree of the third-level prepared roller compacted concrete is not less than 97 percent, and the compaction degree of the second-level prepared roller compacted concrete is not less than 98 percent.
Adopt intelligence to roll monitored control system and grind vibration and carry out real time monitoring, the vibration is ground the parameter and is pressed: constructing 2 times without vibration, 6 times with vibration and 2 times without vibration (the walking speed is 1.0 km/h-1.5 km/h), and grinding the strips which do not meet the grinding requirement to meet the quality requirement.
Under the special complex climatic conditions of strong sunshine, large day-night temperature difference, large evaporation capacity, large humidity change and the like of a Tibetan DG hydropower station, the VC value of the roller compacted concrete has large loss difference under different time periods and different temperature conditions every day, so the VC value control of the roller compacted concrete can not be treated by the same standard, otherwise, the quality control of the roller compacted concrete is not facilitated. The VC value of the roller compacted concrete is accurately adjusted and controlled according to the weather conditions of each time period every day, the good interlayer combination of the roller compacted concrete is ensured by dynamically controlling the VC value of the roller compacted concrete under the complex weather conditions, and the main control key points are as follows: VC value determination, unit water consumption determination and VC value compensation.
The optimal VC value when the compaction thickness, the apparent density and the slurry flooding effect are met under different temperature and humidity conditions is determined through field detection, and the optimal VC value is obtained through statistics and analysis of a large amount of data: establishing a unitary regression relationship curve y of the bin surface air temperature and the VC value under different humidity conditions 1 、y 2 、y 3 Unary regression relationship curve y 1 、y 2 、y 3 The VC value under different humidity conditions with the temperature change of the bin surface is shown in a graph of figure 2 when the humidity is 10-20%, 20-40% and 40-60%. And in the production process, according to the climate environment of the warehouse surface, selecting a corresponding unary regression relationship curve to calculate the VC value suitable for the construction under the climate condition of the warehouse surface.
Factors influencing the VC value of the roller compacted concrete in the production process include: the characteristics and the using amount of the raw materials such as the aggregate, the fly ash, the cement, the admixture and the like are determined in construction, the unit water consumption is most directly influencing the VC value of the roller compacted concrete, and in order to accurately control the VC value of the roller compacted concrete in the construction process, a relation curve graph (figure 3) of the unit water consumption and the VC value and a unitary regression relation curve y of the unit water consumption and the VC value are determined through tests (figure 3) 4 ，y 4 ＝-0.3317X 4 +30.227(R 2 ＝0.994)。
The relation curve diagram (figure 3) of the unit water consumption and the VC value, the accurate unit water consumption of the roller compacted concrete is calculated by utilizing the relation curve diagram (figure 3) of the unit water consumption and the VC value and the water content of the sandstone aggregate according to the calculated VC value suitable for the construction of the warehouse surface climate condition in the production process, so as to achieve the aim of accurately controlling the VC value of the roller compacted concrete.
When strong wind or rainfall (the rain speed is 1-3 mm/h) appears on the surface of the bin, the VC value of the roller compacted concrete needs to be properly compensated according to the strong wind level and the rainfall, so that the roller compacted concrete can be effectively ensured to have good rollability, good plasticity and good interlayer combination.
Using a simple regression curve y 1 、y 2 、y 3 、y 4 In the process of guiding field production, data needs to be collected, sorted and analyzed continuously, and the curve needs to be corrected continuously, so that the curve has better reliability and relevance, and is more favorable for accurately guiding field production.
Due to the adoption of the technical scheme, the invention has the following beneficial effects:
(1) The process has the characteristics of advanced technology, wide application range, economy, environmental protection, easy quality guarantee, high work efficiency and the like. The VC value of the roller compacted concrete can be dynamically controlled according to the climatic environment conditions, so that the roller compacted concrete can adapt to the change of the climatic environment, and the stability of the workability, the workability and the grindability of the roller compacted concrete is ensured; effectively ensures various performances and engineering quality of the roller compacted concrete, and ensures the pouring speed and efficacy of the roller compacted concrete due to the stable and good workability and workability of the roller compacted concrete.
(2) The process is suitable for the complex and changeable single-day climate environment, for example, the production control of the roller compacted concrete under the conditions of large day-night temperature difference (day-night temperature difference is more than 10 ℃) in a day, large temperature difference and large humidity change under the condition of no day illumination in the Tibet high-altitude area, and the problem of accurately carrying out dynamic control on the VC value of the roller compacted concrete under the complex climate environment of the Qinghai-Tibet plateau is solved.
(3) The process firstly detects the quality of the raw materials entering the ground, allows the raw materials to enter the ground for use after the raw materials are detected to be qualified, secondly controls the quality of the raw materials in the production process of the roller compacted concrete, and allows the raw materials to be used for the production of the concrete after the raw materials are detected to be qualified; and then collecting the optimal VC value when the compaction thickness, the apparent density and the slurry spreading effect are met under different temperature and humidity conditions on the surface of the bin, determining a relation curve of the unit water consumption of the roller compacted concrete and the VC value according to indoor tests by establishing a unitary regression relation curve of the surface temperature and the optimal VC value under different humidity conditions, establishing a unitary regression relation curve of the VC value and the unit water consumption, guiding field production by using the unitary regression relation curve, and continuously collecting relevant data in the production process to continuously correct the unitary regression relation curve.
(4) This application compares with traditional roller compacted concrete VC value control, and the advantage can be according to the VC value of storehouse face climatic environment accurate control roller compacted concrete, combines between in order to guarantee roller compacted concrete good layer through VC value dynamic control roller compacted concrete under complicated climatic condition. Therefore, the technical scheme is suitable for the production control of the roller compacted concrete in the areas with complicated and changeable single-day climate environments, such as the special strong sunshine of the Qinghai-Tibet plateau, large day-night temperature difference, large evaporation capacity, large humidity change and the like under the complicated climate conditions of four seasons per day.
(5) The technical scheme of the application enables the VC value of the roller compacted concrete under the complex climatic condition to dynamically form a standardized control program, lays a foundation for creating national high-quality engineering, and is convenient for building and accumulating technical parameters for the roller compacted concrete dam of the hydropower station upstream and downstream of the drainage basin.
(6) Under the condition that the VC value is not dynamically controlled, the phenomena of undersize and oversize can occur, and the phenomenon that the field VC value is oversize is represented as follows: aggregate is easy to concentrate after unloading, the common method is to adopt manual work to concentrate the aggregate for treatment, aggregate concentration, roller compacted concrete mortar spraying treatment and the like need to fix at least 4 workers per shift, and the total of at least 600 shifts of roller compacted concrete pouring of the project is counted according to the site construction progress, so that the construction labor cost is increased. After the method is adopted for carrying out VC value dynamic control, the labor cost of aggregate concentration, roller compacted concrete mortar spraying and the like in civil engineering treatment in the roller compacted concrete pouring process can be reduced, good interlayer combination of the roller compacted concrete is ensured, the risk of water seepage between dam layers is reduced, and the later maintenance cost of the dam is reduced.
Drawings
In order to illustrate the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only some examples of the present invention, and for a person skilled in the art, without inventive step, other drawings can be obtained according to these drawings:
FIG. 1 is a flow chart of the process of the present application;
FIG. 2 is a graph showing VC content as a function of the temperature of the cabin surface under different humidity conditions;
FIG. 3 is a graph of VC versus water usage per unit.
In the drawings: the three univariate regression curves of y1, y2 and y3 are curves of VC value varying with the temperature of the cabin surface when the humidity is 10-20%, 20-40% and 40-60%.
Detailed Description
The following is a detailed description of the embodiments of the present invention, but the present invention is not limited to these embodiments, and any modifications or substitutions in the basic spirit of the embodiments are included in the scope of the present invention as claimed in the claims.
Example 1
A construction method for dynamically controlling VC value of roller compacted concrete under complex climate conditions comprises the following steps:
(1) Raw material detection: detecting cement, fly ash, a water reducing agent, an air entraining agent, coarse aggregate, fine aggregate and mixing water for producing roller compacted concrete according to specific detection indexes and detection frequency;
detecting a fineness modulus, a stone powder content, a particle content, a water content and a methylene blue MB value of the fine aggregate, wherein the fineness modulus, the stone powder content, the particle content and the methylene blue MB value are detected once a day, and the water content is detected 1 time every 2 hours; detecting the oversize content, the sub-diameter content, the middle-diameter screen residue content, the sludge content and the water content of small stones by the coarse aggregate, wherein the oversize content, the sub-diameter content, the middle-diameter screen residue content and the sludge content are detected for 1 time every 8 hours, and the water content is detected for one time every 2 hours; detecting the solution preparation concentration of the admixture every 8h for 1 time;
(2) Determination of VC value and unit water consumption: determining at different temperatures based on field testingVC value when the compaction thickness, apparent density and slurry effect are satisfied under the humidity condition, and establishing a unitary regression relation curve y of the bin surface air temperature and the VC value under different humidity conditions 1 、y 2 、y 3 Selecting corresponding unitary regression relation curve to calculate VC value suitable for construction under the storehouse surface climate condition according to the storehouse surface climate environment in the production process, and establishing unitary regression relation curve y of unit water consumption and VC value 4 ；
The unary regression relationship curve y 1 ＝-0.0493X 1 +2.7(R 2 VC value univariate regression relation curve with humidity of 10-20% = 0.9952); y is 2 ＝-0.0621X 2 +3.2571(R 2 VC value univariate regression relation curve with humidity of 20-40% = 0.998); y is 3 ＝-0.0621X 3 +3.5571(R 2 VC value univariate regression relation curve with humidity of 40-60% of 0.998); y is 4 ＝-0.3317X 4 +30.227(R 2 ＝0.994)；
(3) Roller compacted concrete production and machine outlet detection: feeding the raw materials into a concrete mixer, uniformly mixing, and detecting the mixing performance of VC value, gas content and condensation time at a roller compacted concrete outlet to see whether the mixing performance meets the requirements or not;
if the roller compacted concrete is qualified, entering the next procedure, if the roller compacted concrete is unqualified, entering the waste treatment procedure, returning to the batching procedure, and readjusting the raw material ratio;
(4) And (3) field detection of roller compacted concrete: detecting the mixing performance of the on-site VC value, the air content and the setting time of the roller compacted concrete qualified by the machine outlet detection to see whether the mixing performance meets the requirements;
if the roller compacted concrete is qualified in field detection, entering the next procedure, if the roller compacted concrete is unqualified in field detection, entering a waste treatment procedure, returning to a batching procedure, and readjusting the mixture ratio of the raw materials;
(5) Pouring and correcting: the roller compacted concrete qualified by detection is cast in situ, the compactness of the roller compacted concrete is detected, the VC value, the air temperature and the humidity data are recorded at the same time, and the real-time data is utilized to carry out on the unitary regression relation curve y 1 、y 2 、y 3 、y 4 Correcting and guiding field production; the compaction degree of the roller compacted concrete meets the requirements that the compaction degree of the third-level mixed roller compacted concrete is more than or equal to 97 percent, and the compaction degree of the second-level mixed roller compacted concrete is more than or equal to 98 percent.
Further, when strong wind or rainfall occurs on the surface of the bin, the VC value of the roller compacted concrete is compensated according to the grade of the strong wind and the rainfall; the rain speed of the rainfall is 1mm/h.
Example 2
A construction method for dynamically controlling VC value of roller compacted concrete under complex climate conditions comprises the following steps:
(1) Raw material detection: detecting cement, fly ash, a water reducing agent, an air entraining agent, coarse aggregate, fine aggregate and mixing water for producing roller compacted concrete according to specific detection indexes and detection frequency;
detecting a fineness modulus, a stone powder content, a particle content, a water content and a methylene blue MB value of the fine aggregate, wherein the fineness modulus, the stone powder content, the particle content and the methylene blue MB value are detected once a day, and the water content is detected 1 time every 2 hours; detecting the oversize content, the content of the son diameter, the content of the medium diameter screen residue, the mud content and the water content of small stones by the coarse aggregate, wherein the oversize content, the content of the son diameter, the content of the medium diameter screen residue and the mud content are detected for 1 time every 8 hours, and the water content is detected for one time every 2 hours; detecting the solution preparation concentration of the admixture every 8h for 1 time;
(2) Determination of VC value and unit water consumption: determining VC values when the compaction thickness, the apparent density and the slurry flooding effect are met under different temperature and humidity conditions according to field detection, and establishing a unitary regression relation curve y of the bin surface air temperature and the VC values under different humidity conditions 1 、y 2 、y 3 Selecting corresponding unitary regression relation curve to calculate VC value suitable for construction under the storehouse surface climate condition according to the storehouse surface climate environment in the production process, and establishing unitary regression relation curve y of unit water consumption and VC value 4 ；
The curve y of the unary regression relationship 1 ＝-0.0493X 1 +2.7(R 2 VC value univariate regression relation curve with humidity of 10-20% = 0.9952); y is 2 ＝-0.0621X 2 +3.2571(R 2 =0.998, humidityA univariate regression relationship curve of VC value of 20-40%); y is 3 ＝-0.0621X 3 +3.5571(R 2 VC value univariate regression relation curve with humidity of 40-60% of 0.998); y is 4 ＝-0.3317X 4 +30.227(R 2 ＝0.994)；
(3) Roller compacted concrete production and machine outlet detection: feeding the raw materials into a concrete mixer, uniformly mixing, and detecting the mixing performance of VC value, gas content and condensation time at a roller compacted concrete outlet to see whether the mixing performance meets the requirements or not;
if the roller compacted concrete is qualified, entering the next procedure, if the roller compacted concrete is unqualified, entering the waste treatment procedure, returning to the batching procedure, and readjusting the raw material ratio;
(4) And (3) field detection of roller compacted concrete: detecting the mixing performance of the on-site VC value, the air content and the setting time of the roller compacted concrete qualified by the machine outlet detection to see whether the mixing performance meets the requirements or not;
if the roller compacted concrete is qualified in field detection, entering the next procedure, if the roller compacted concrete is unqualified in field detection, entering a waste treatment procedure, returning to a batching procedure, and readjusting the raw material ratio;
(5) Pouring and correcting: the roller compacted concrete qualified by detection is cast in situ, the compactness of the roller compacted concrete is detected, the VC value, the air temperature and the humidity data are recorded at the same time, and the real-time data is utilized to carry out on the unitary regression relation curve y 1 、y 2 、y 3 、y 4 Correcting and guiding field production; the compaction degree of the roller compacted concrete meets the requirements that the compaction degree of the third-level mixed roller compacted concrete is more than or equal to 97 percent, and the compaction degree of the second-level mixed roller compacted concrete is more than or equal to 98 percent.
Further, when the surface of the silo is windy or raining, the VC value of the roller compacted concrete is compensated according to the level of the windy and the rainfall; the rain speed of the rainfall is 3mm/h.
Example 3
A construction method for dynamically controlling the VC (vibration compaction) value of roller compacted concrete under complex climatic conditions comprises the following steps:
(1) Raw material detection: detecting cement, fly ash, a water reducing agent, an air entraining agent, coarse aggregate, fine aggregate and mixing water for producing roller compacted concrete according to specific detection indexes and detection frequency;
detecting a fineness modulus, a stone powder content, a particle content, a water content and a methylene blue MB value of the fine aggregate, wherein the fineness modulus, the stone powder content, the particle content and the methylene blue MB value are detected once a day, and the water content is detected 1 time every 2 hours; detecting the oversize content, the sub-diameter content, the middle-diameter screen residue content, the sludge content and the water content of small stones by the coarse aggregate, wherein the oversize content, the sub-diameter content, the middle-diameter screen residue content and the sludge content are detected for 1 time every 8 hours, and the water content is detected for one time every 2 hours; detecting the solution preparation concentration of the admixture every 8h for 1 time;
(2) Determination of VC value and unit water consumption: determining VC (volatile organic compound) values meeting compaction thickness, apparent density and slurry flooding effects under different temperature and humidity conditions according to field detection, and establishing a unitary regression relation curve y of bin surface temperature and VC values under different humidity conditions 1 、y 2 、y 3 Selecting corresponding unitary regression relation curve to calculate VC value suitable for construction under cabin surface climate condition during production process according to cabin surface climate environment, and establishing unitary regression relation curve y of unit water consumption and VC value 4 ；
The unary regression relationship curve y 1 ＝-0.0493X 1 +2.7(R 2 VC value univariate regression relation curve with humidity of 10-20% = 0.9952); y is 2 ＝-0.0621X 2 +3.2571(R 2 VC value univariate regression relation curve with humidity of 20-40% = 0.998); y is 3 ＝-0.0621X 3 +3.5571(R 2 VC value univariate regression relation curve with humidity of 40-60% of 0.998); y is 4 ＝-0.3317X 4 +30.227(R 2 ＝0.994)；
(3) Roller compacted concrete production and machine outlet detection: feeding the raw materials into a concrete mixer, uniformly mixing, and detecting the mixing performance of the VC value, the gas content and the setting time of a roller compacted concrete outlet to see whether the mixing performance meets the requirements;
if the roller compacted concrete is qualified, entering the next procedure, if the roller compacted concrete is unqualified, entering the waste treatment procedure, returning to the batching procedure, and readjusting the raw material ratio;
(4) And (3) field detection of roller compacted concrete: detecting the mixing performance of the on-site VC value, the air content and the setting time of the roller compacted concrete qualified by the machine outlet detection to see whether the mixing performance meets the requirements or not;
if the roller compacted concrete is qualified in field detection, entering the next procedure, if the roller compacted concrete is unqualified in field detection, entering a waste treatment procedure, returning to a batching procedure, and readjusting the raw material ratio;
(5) Pouring and correcting: the roller compacted concrete qualified by detection is cast in situ, the compactness of the roller compacted concrete is detected, the VC value, the air temperature and the humidity data are recorded at the same time, and the real-time data is utilized to carry out on the unitary regression relation curve y 1 、y 2 、y 3 、y 4 Correcting and guiding field production; the compaction degree of the roller compacted concrete meets the condition that the compaction degree of the three-level roller compacted concrete is more than or equal to 97 percent, and the compaction degree of the two-level roller compacted concrete is more than or equal to 98 percent.
Further, when strong wind or rainfall occurs on the surface of the bin, the VC value of the roller compacted concrete is compensated according to the grade of the strong wind and the rainfall; the rain speed of the rainfall is 2mm/h.
Application case 1
The method of example 1 was used to construct tibetan DG hydropower station engineering. The DG hydropower station is located in the county of Sungnan City, shandong province of Tibet, is a type 2 project with the development task mainly based on power generation, the normal water level of the reservoir is 3447.00m, and the corresponding storage capacity is 0.5528 hundred million m 3 The installed capacity of the power station is 660MW, the average power generation amount of years is 32.045 hundred million kW.h, and the guaranteed output (P = 5%) is 173.43MW.
The power station hub building comprises a water retaining building, a flood discharge energy dissipation building, a water diversion power generation system, a booster station and the like. The barrage is a roller compacted concrete gravity dam, the dam crest elevation is 3451.00m, the maximum dam height is 117.0m, and the dam crest length is 385.0m. The power plant adopts the arrangement of dam back type, mainly comprises main plant, auxiliary plant, transformer substation, etc., and the size of the main plant is 163.00m × 29.50m × 63.50m (length × width × height), and 4 mixed flow type hydroelectric generating sets with single machine capacity of 165MW are installed.
Through engineering practice, the construction method plays an important role under the complex climate condition of the high-altitude area, various performances and quality of the roller compacted concrete on site are guaranteed through dynamic control of the VC value of the roller compacted concrete, construction efficiency is improved, the Tibetan DG hydropower station is well built, a national high-quality project is created, powerful technical support is provided, and the construction method is well commented by owners, supervision and design parties.
Application case 2
The method of the embodiment 2 is adopted to carry out construction on the Tibet Hunan river water conservancy hub and the supporting irrigation area project. The Tibet Xiang river water conservancy hub and the supporting irrigation area project are located in the Nikedian city of the Tibet autonomous region, and are large (2) type water conservancy hub projects which mainly perform irrigation, water supply, improve the ecological environment of a protected area, and comprehensively utilize power generation and the like. Total storage capacity of reservoir 1.134X 108m 3 The installed capacity of the power station is 40MW, and the hub project comprises a dam, a tunnel type spillway, a diversion flood discharge tunnel, a water diversion power generation system, a fishway, a power generation plant and the like. Designed water diversion flow rate 11372m for matched irrigation area 3 S, increase quoted flow 14.66m 3 The land area of the irrigated area is 32.07 ten thousand mu, the designed irrigated area is 12.49 ten thousand mu, and the annual water supply is 669 ten thousand mu m 3 。
According to the embodiment 2, the construction method guides the site construction, the dynamic control of the concrete slump is realized, the working performance such as the workability and the workability of the concrete is effectively ensured, the pouring and construction speed and efficiency of the concrete are guaranteed, the key problem of the concrete production is solved, and a good effect is achieved.
In conclusion, the process has the characteristics of advanced technology, wide application range, economy, environmental protection, high work efficiency and the like, and the quality is easy to guarantee. The VC value of the roller compacted concrete can be dynamically controlled according to the climatic environment conditions, so that the roller compacted concrete can adapt to the change of the climatic environment, and the stability of the workability, the workability and the grindability of the roller compacted concrete is ensured; the method effectively ensures various performances and engineering quality of the roller compacted concrete, and ensures the pouring speed and efficacy of the roller compacted concrete due to the stability, good workability and peaceability of the roller compacted concrete, so that the VC value of the roller compacted concrete under complex climatic conditions dynamically forms a standardized control program, thereby laying a foundation for creating national high-quality engineering and facilitating the construction of the roller compacted concrete dam of the hydropower station upstream and downstream of the watershed to accumulate technical parameters.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (8)

1. A construction method for dynamically controlling VC (compaction concrete) value of rolled concrete under complex climatic conditions is characterized by comprising the following steps:
(1) Raw material detection: detecting cement, fly ash, a water reducing agent, an air entraining agent, coarse aggregate, fine aggregate and mixing water for producing roller compacted concrete according to specific detection indexes and detection frequency;
(2) Determination of VC value and unit water consumption: determining VC values when the compaction thickness, the apparent density and the slurry flooding effect are met under different temperature and humidity conditions according to field detection, and establishing a unitary regression relation curve y of the bin surface air temperature and the VC values under different humidity conditions 1 、y 2 、y 3 Selecting corresponding unitary regression relation curve to calculate VC value suitable for construction under the storehouse surface climate condition according to the storehouse surface climate environment in the production process, and establishing unitary regression relation curve y of unit water consumption and VC value 4 ；
(3) Roller compacted concrete production and machine outlet detection: feeding the raw materials into a concrete mixer, uniformly mixing, and detecting the mixing performance of VC value, gas content and condensation time at a roller compacted concrete outlet to see whether the mixing performance meets the requirements or not;
(4) And (3) field detection of roller compacted concrete: detecting the mixing performance of the on-site VC value, the air content and the setting time of the roller compacted concrete qualified by the machine outlet detection to see whether the mixing performance meets the requirements;
(5) Pouring and correcting: the roller compacted concrete qualified by detection is cast in situ, the compactness of the roller compacted concrete is detected, the VC value, the air temperature and the humidity data are recorded at the same time, and the real-time data is utilized to carry out on the unitary regression relation curve y 1 、y 2 、y 3 、y 4 Correcting and guiding field production;
in step (2), the univariate regression relationship curve y 1 ＝-0.0493X 1 +2.7 VC value unary regression relation curve y with humidity of 10-20% 1 ，R 2 ＝0.9952；y 2 ＝-0.0621X 2 +3.2571 VC value unitary regression relation curve y with humidity of 20-40% 2 ，R 2 ＝0.998；y 3 ＝-0.0621X 3 +3.5571, VC value unitary regression relation curve y with humidity of 40-60% 3 ，R 2 ＝0.998；y 4 ＝-0.3317X 4 +30.227，R 2 =0.994; and said X 1 、X 2 、X 3 Respectively representing the temperature of the cabin surface when the humidity is 10-20%, 20-40% and 40-60%; x 4 Representing the unit water usage.
2. The construction method for dynamically controlling the VC (compaction concrete) value of the roller compacted concrete under the complex climate condition as recited in claim 1, wherein: in the step (1), the fine aggregate is detected for fineness modulus, stone powder content, particle content, water content and methylene blue MB value, wherein the fineness modulus, the stone powder content, the particle content and the methylene blue MB value are detected once a day, and the water content is detected for 1 time every 2 hours.
3. The construction method for dynamically controlling the VC (vibration compaction concrete) value of the roller compacted concrete under the complex climate conditions as recited in claim 1, wherein the construction method comprises the following steps: in the step (1), detecting the oversize content, the son content, the middle-diameter oversize content, the mud content and the small stone water content of the coarse aggregate, wherein the oversize content, the son content, the middle-diameter oversize content and the mud content are detected for 1 time every 8 hours, and the water content is detected for once every 2 hours; the additive is tested for the solution preparation concentration 1 time every 8 hours.
4. The construction method for dynamically controlling the VC (vibration compaction concrete) value of the roller compacted concrete under the complex climate conditions as recited in claim 1, wherein the construction method comprises the following steps: and (3) entering the next procedure if the roller compacted concrete outlet is qualified in detection, entering a waste treatment procedure if the roller compacted concrete outlet is unqualified in detection, returning to the batching procedure, and readjusting the raw material ratio.
5. The construction method for dynamically controlling the VC (compaction concrete) value of the roller compacted concrete under the complex climate condition as recited in claim 1, wherein: and (4) entering the next procedure if the roller compacted concrete is qualified in field detection, entering a waste treatment procedure if the roller compacted concrete is unqualified in field detection, returning to the batching procedure, and readjusting the raw material ratio.
6. The construction method for dynamically controlling the VC (vibration compaction concrete) value of the roller compacted concrete under the complex climate conditions as recited in claim 1, wherein the construction method comprises the following steps: in the step (5), the compactness of the roller compacted concrete meets the requirement that the compactness of the third-level roller compacted concrete is more than or equal to 97 percent, and the compactness of the second-level roller compacted concrete is more than or equal to 98 percent.
7. The construction method for dynamically controlling the VC (compaction concrete) value of the roller compacted concrete under the complex climate condition as recited in claim 1, wherein: and when the surface of the bin is windy or raining, compensating the VC value of the roller compacted concrete according to the windy level and the rainfall.
8. The construction method for dynamically controlling the VC (compaction concrete) value of the roller compacted concrete under the complex climate condition as recited in claim 7, wherein: the rainfall speed is 1-3 mm/h.
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