Rock-fill concrete dam layer reinforcing composition and construction method thereof

Abstract

The invention discloses a rock-fill concrete dam layer reinforcing composition and a construction method thereof. The rock-fill concrete dam layer reinforcing composition at least comprises the following materials in parts by weight: 10-20 parts of pure acrylic emulsion, 1-5 parts of an expanding agent, 40-60 parts of Portland cement and 15-25 parts of water. The anti-seepage performance and the shear strength of the rock-fill concrete dam layer can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rockfill concrete material, and in particular to a rockfill concrete dam layer surface reinforcing composition and a construction method thereof. BACKGROUND

[0002] As a water retaining structure for intercepting water flow in rivers and channels, the rockfill concrete dam has the characteristics of fast construction speed, low comprehensive cost, safety and reliability, energy saving and emission reduction, and environmental friendliness, and has been widely used in water conservancy and hydropower, transportation and other engineering.

[0003] The rockfill concrete dam generally adopts a construction process of layered pouring (or referred to as warehouse segment pouring) (for example, the layer thickness is 1.5 m to 3.0 m), and in the process of layered pouring, the concrete cannot be continuously poured to form a layer surface. The layer surface is a weak area of seepage concentration channel and anti-sliding stability of the rockfill concrete dam, which can cause certain influence on the safety and stability of the rockfill concrete dam. Moreover, with the increase of the height of the rockfill concrete dam, the problems of poor anti-seepage performance and poor shear strength of the layer surface of the rockfill concrete dam are more prominent, which limits the development of the rockfill concrete dam. SUMMARY

[0004] Therefore, the embodiments of the present application provide a rockfill concrete dam layer surface reinforcing composition and a construction method thereof, which are used to solve the technical problems of poor anti-seepage performance and poor shear strength of the layer surface of the rockfill concrete dam.

[0005] In a first aspect, the embodiments of the present application provide a rockfill concrete dam layer surface reinforcing composition, which at least includes the following materials in the weight parts: 10 to 20 parts of pure acrylic emulsion, 1 to 5 parts of expanding agent, 40 to 60 parts of Portland cement, and 15 to 25 parts of water.

[0006] According to some embodiments of the present application, the rockfill concrete dam layer surface reinforcing composition further includes silica fume or fly ash, and the weight parts of the silica fume or fly ash are 5 to 10 parts; at this time, the weight parts of the Portland cement are further reduced to 35 to 50 parts.

[0007] According to some embodiments of the present application, the rockfill concrete dam layer surface reinforcing composition further includes silica fume and fly ash, and the weight parts of the silica fume and the fly ash are both 5 to 10 parts; at this time, the weight parts of the Portland cement are further reduced to 30 to 40 parts.

[0008] According to some embodiments of the present application, the expanding agent includes one of magnesium oxide, calcium oxide or a composite of magnesium oxide and calcium oxide.

[0009] In a second aspect, the embodiments of the present application provide a rock-fill concrete dam, the rock-fill concrete dam comprising a plurality of bin sections stacked along a height direction, and a rock-fill concrete dam layer surface reinforcing composition as provided in the first aspect is arranged between any two adjacent bin sections, and the rock-fill concrete dam layer surface reinforcing composition is arranged on an upper surface of a lower bin section among the any two adjacent bin sections.

[0010] According to some embodiments of the present application, optionally, the thickness of the rock-fill concrete dam layer surface reinforcing composition arranged between any two adjacent bin sections is 1-3 cm.

[0011] In a third aspect, the embodiments of the present application provide a construction method of a rock-fill concrete dam layer surface reinforcing composition, comprising: forming an i-th bin section of a rock-fill concrete dam by pouring concrete, wherein i is a positive integer; after the concrete of the i-th bin section is solidified, cleaning a layer surface of the i-th bin section; after the rock-fill concrete dam layer surface reinforcing composition as provided in the first aspect is uniformly mixed, the rock-fill concrete dam layer surface reinforcing composition is arranged on an upper surface of the i-th bin section; film curing is performed on the rock-fill concrete dam layer surface reinforcing composition arranged on the upper surface of the i-th bin section, and the film is removed after a preset curing time is reached; the above steps are cycled to construct an i+1-th bin section, until the construction of the plurality of bin sections of the rock-fill concrete dam is completed.

[0012] According to some embodiments of the present application, after the rock-fill concrete dam layer surface reinforcing composition is uniformly mixed, the rock-fill concrete dam layer surface reinforcing composition is arranged on the upper surface of the i-th bin section, and further comprising: after the rock-fill concrete dam layer surface reinforcing composition is uniformly mixed, the rock-fill concrete dam layer surface reinforcing composition is sprayed or brushed and arranged on the upper surface of the i-th bin section.

[0013] According to some embodiments of the present application, after the rock-fill concrete dam layer surface reinforcing composition is uniformly mixed, the rock-fill concrete dam layer surface reinforcing composition is sprayed or brushed and arranged on the upper surface of the i-th bin section, and further comprising: 1-3 cm thick rock-fill concrete dam layer surface reinforcing composition is sprayed or brushed on the upper surface of the i-th bin section.

[0014] The rockfill concrete dam layer surface reinforcing composition and the construction method thereof provided by the embodiment of the present application comprises at least the following materials in the following weight parts: 10-20 parts of pure acrylic emulsion, 1-5 parts of expanding agent, 40-60 parts of Portland cement, and 15-25 parts of water. The Portland cement has good adhesion and can be used to better connect two adjacent bin sections of the rockfill concrete dam. The addition of the expanding agent can reduce the cracking caused by the shrinkage of the Portland cement, reduce the gap between the two adjacent bin sections of the rockfill concrete dam, further improve the connection strength between the two adjacent bin sections of the rockfill concrete dam, and make the connection layer of the two adjacent bin sections have good impermeability and shear strength. In addition, the pure acrylic emulsion has good adhesion, which can further improve the connection strength between the two adjacent bin sections of the rockfill concrete dam, and the film formed after the drying of the pure acrylic emulsion has good flexibility and is not easy to crack, which can further improve the impermeability. The rockfill concrete dam layer surface reinforcing composition and the weight parts of the above materials can not only improve the impermeability of the rockfill concrete dam layer surface, but also improve the shear strength of the rockfill concrete dam layer surface, solve the defects of poor impermeability and poor shear strength of the rockfill concrete dam layer surface, and thus provide quality guarantee for the safe operation and maintenance of the rockfill concrete dam. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings in the embodiments of the present application.

[0016] Figure 1 A structural schematic diagram of the rockfill concrete dam layer surface reinforcing composition provided by the embodiment of the present application.

[0017] Figure 2 A flowchart of the construction method of the rockfill concrete dam layer surface reinforcing composition provided by the embodiment of the present application.

[0018] Figure 3 A construction process schematic diagram of the rockfill concrete dam layer surface reinforcing composition. DETAILED DESCRIPTION

[0019] The features and exemplary embodiments of various aspects of the present application will be described in detail below, in order to make the purposes, technical solutions and advantages of the present application more clear and apparent, the present application will be further described in detail below in combination with the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, but not to limit the present application. The present application can be implemented without some of these specific details by those skilled in the art. The following description of the embodiments is only to provide a better understanding of the present application by showing examples of the present application.

[0020] It should be noted that the relative terms such as first and second and the like in this text are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment. Without more limitations, the elements defined by the statement "include" do not exclude the presence of additional identical elements in the process, method, article or equipment including the elements.

[0021] It should be understood that the term "and / or" used herein is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this text generally represents that the front and rear associated objects are in an "or" relationship.

[0022] Various modifications and changes can be made to the present application without departing from the spirit or scope of the present application, which will be apparent to those skilled in the art. Therefore, the present application intends to cover the modifications and changes of the present application falling within the scope of the corresponding claims (claimed technical solutions) and their equivalents. It should be noted that the embodiments provided by the present application can be combined with each other without contradiction.

[0023] Before describing the technical solutions provided by the embodiments of the present application, in order to facilitate the understanding of the embodiments of the present application, the present application first specifically describes the problems existing in the related art:

[0024] As a water retaining structure for intercepting water flow in rivers and channels, the rock-filled concrete dam has the characteristics of fast construction speed, low comprehensive cost, safety and reliability, energy saving and emission reduction, and environmental friendliness, and has been widely used in water conservancy and hydropower, transportation and other engineering.

[0025] The rock-filled concrete dam generally adopts the construction technology of layer pouring (or called warehouse segment pouring) (such as layer thickness of 1.5m-3.0m), and in the process of layer pouring, the concrete cannot be continuously poured to form a layer surface. The layer surface is a weak area of seepage concentration channel and anti-sliding stability of the rock-filled concrete dam, which will cause certain influence on the safety and stability of the rock-filled concrete dam. Moreover, with the increase of the height of the rock-filled concrete dam, the problems of poor anti-seepage performance and poor shear strength of the layer surface of the rock-filled concrete dam are more prominent, which limits the development of the rock-filled concrete dam.

[0026] To solve the above technical problems, the present application firstly covers cement paste (i.e. a mixture of cement and water) between two adjacent bin sections of the rock-fill concrete dam. For example, after the lower bin section is set, a certain thickness of cement paste is covered on the upper surface of the lower bin section. After the cement paste is set into solid, the upper bin section is poured thereon. However, it is found through verification that, due to the poor impermeability of cement itself and the shrinkage characteristics of cement, there is still a relatively large crack between the two adjacent bin sections of the rock-fill concrete dam, and the impermeability and shear strength of the connecting layer (or connecting part) between the two adjacent bin sections are still poor.

[0027] Therefore, the present application adds a certain proportion of flexible material to the cement paste to improve the impermeability of the cement paste. However, adding a certain proportion of flexible material to the cement paste still cannot solve the problem of easy shrinkage and cracking of cement, and therefore the present application further considers adding an expanding agent to the cement paste to reduce the cracking caused by the shrinkage of cement and reduce the gap between the two adjacent bin sections of the rock-fill concrete dam, so as to improve the connecting strength between the two adjacent bin sections of the rock-fill concrete dam. Finally, through experiments and verification, a rock-fill concrete dam layer reinforcing composition mainly composed of pure acrylic emulsion, expanding agent, Portland cement and water is obtained.

[0028] The rock-fill concrete dam layer reinforcing composition provided by the embodiments of the present application is introduced below.

[0029] The rock-fill concrete dam layer reinforcing composition provided by the embodiments of the present application can at least include the following materials in the following weight parts: pure acrylic emulsion 10-20 parts, expanding agent 1-5 parts, Portland cement 40-60 parts, and water 15-25 parts.

[0030] The pure acrylic emulsion is a water-based polymer emulsion with acrylic acid and its esters as the main components. It is a small particle suspension formed in an aqueous phase by polymerizing acrylic acid monomers or their esters. The pure acrylic emulsion has good adhesion, which is beneficial to improve the connecting strength between the two adjacent bin sections of the rock-fill concrete dam. In addition, the film formed after drying of the pure acrylic emulsion has good flexibility and is not easy to crack, which can improve the impermeability.

[0031] By adding a certain amount of expanding agent, the rock-fill concrete dam layer reinforcing composition can be expanded, the cracking caused by the shrinkage of Portland cement can be reduced, the gap between the two adjacent bin sections of the rock-fill concrete dam can be reduced, and the connecting strength between the two adjacent bin sections of the rock-fill concrete dam can be improved, so that the connecting layer between the two adjacent bin sections has good impermeability and shear strength.

[0032] The portland cement has good adhesion, durability and frost resistance, and high strength, and the hardened portland cement has good compressive strength and tensile strength. Due to the good adhesion of the portland cement, the two adjacent bin sections of the rockfill concrete dam can be better connected together. The portland cement can be any type of portland cement, such as 32.5 grade portland cement, 42.5 grade portland cement or 52.5 grade portland cement, etc., which is not limited in the present application. The numbers of 32.5 and the like represent the compressive strength grade of the cement, in units of megapascal (MPa), for example, the compressive strength of 32.5 grade portland cement is greater than or equal to 32.5 MPa at 28 days.

[0033] The rockfill concrete dam layer surface reinforcing composition provided by the embodiments of the present application at least includes the following materials in parts by weight: 10-20 parts of pure acrylic emulsion, 1-5 parts of expanding agent, 40-60 parts of portland cement, and 15-25 parts of water. Due to the good adhesion of the portland cement, the two adjacent bin sections of the rockfill concrete dam can be better connected together. By adding the expanding agent to expand, the cracking caused by the shrinkage of the portland cement can be reduced, the gap between the two adjacent bin sections of the rockfill concrete dam can be reduced, and the connection strength between the two adjacent bin sections of the rockfill concrete dam can be further improved, so that the connection layer of the two adjacent bin sections has good impermeability and shear strength. In addition, the pure acrylic emulsion has good adhesion, which can further improve the connection strength between the two adjacent bin sections of the rockfill concrete dam, and the film formed after drying of the pure acrylic emulsion has good flexibility and is not easy to crack, which can further improve the impermeability. The rockfill concrete dam layer surface reinforcing composition using the above materials and their parts by weight can not only improve the impermeability of the rockfill concrete dam layer surface, but also improve the shear strength of the rockfill concrete dam layer surface, solve the defects of poor impermeability and poor shear strength of the rockfill concrete dam layer surface, and thus provide quality assurance for the safe operation and maintenance of the rockfill concrete dam.

[0034] The effects of the rockfill concrete dam layer surface reinforcing composition provided by the embodiments of the present application are verified in combination with Example One.

[0035] In Example One, control experiments of Group 1, Group 2 and Group 3 are carried out.

[0036] In Group 1, the rockfill concrete dam layer surface reinforcing composition is not covered between the two adjacent bin sections of the rockfill concrete dam, core sampling is carried out at the connection between the two adjacent bin sections (such as the upper surface of the lower bin section) to obtain sample 1, the impermeability grade of sample 1 is detected by using a concrete impermeability instrument, and the ultimate shear strength of sample 1 is detected by using a direct shear instrument.

[0037] The second group covers 2 cm of the rockfill concrete dam layer surface reinforcing composition between the adjacent two bin sections of the rockfill concrete dam, the rockfill concrete dam layer surface reinforcing composition comprising the following materials in parts by weight: 20 parts of pure acrylic emulsion, 5 parts of expanding agent, 60 parts of Portland cement, and 25 parts of water. Core drilling sampling is performed at the joint between the adjacent two bin sections of the rockfill concrete dam (e.g., the rockfill concrete dam layer surface reinforcing composition), to obtain sample 2. The impermeability grade of sample 2 is detected by using a concrete impermeability tester, and the ultimate shear strength of sample 2 is detected by using a direct shear tester.

[0038] The third group covers 2 cm of the rockfill concrete dam layer surface reinforcing composition between the adjacent two bin sections of the rockfill concrete dam, the rockfill concrete dam layer surface reinforcing composition comprising the following materials in parts by weight: 10 parts of pure acrylic emulsion, 1 part of expanding agent, 40 parts of Portland cement, and 15 parts of water. Core drilling sampling is performed at the joint between the adjacent two bin sections of the rockfill concrete dam (e.g., the rockfill concrete dam layer surface reinforcing composition), to obtain sample 3. The impermeability grade of sample 3 is detected by using a concrete impermeability tester, and the ultimate shear strength of sample 3 is detected by using a direct shear tester.

[0039] Table 1 shows the impermeability grades and the ultimate shear strengths of sample 1, sample 2, and sample 3.

[0040] Table 1

[0041] Permeation resistance rating Ultimate shear strength / MPa Sample 1 W4 6.9 Sample 2 W6 10.9 Sample 3 W4 7.3

[0042] As shown in Table 1, compared with sample 1 without covering the rockfill concrete dam layer surface reinforcing composition, the impermeability grade of sample 2 is improved from W4 to W6, and the ultimate shear strength is improved from 6.9 MPa to 10.9 MPa, after the various materials in the rockfill concrete dam layer surface reinforcing composition reach the maximum value, and the impermeability performance and the shear strength are significantly improved. Even after the various materials in the rockfill concrete dam layer surface reinforcing composition reach the minimum value, the impermeability grade of sample 3 can still reach W4, and the ultimate shear strength of sample 3 can be improved from 6.9 MPa to 7.3 MPa. Therefore, the rockfill concrete dam layer surface reinforcing composition provided by the embodiments of the present application helps to improve the impermeability performance and / or the shear strength.

[0043] The impermeability grade is a grade standard used to represent the impermeability performance of concrete in construction engineering. The impermeability grade is generally divided into multiple grades such as W0, W1, W2, W3, W4, W5, and W6, wherein W0 represents no impermeability ability, and the greater the numerical value of the impermeability grade, the higher the impermeability grade, and the stronger the impermeability performance. For example, W6 > W4, which indicates that the impermeability performance of the impermeability grade W6 is better than that of the impermeability grade W4.

[0044] According to some embodiments of the present application, the rock-fill concrete dam layer surface reinforcing composition can further include silica fume, and the weight of the silica fume is 5-10 parts. At this time, the weight of the Portland cement is further reduced to 35-50 parts. That is, the rock-fill concrete dam layer surface reinforcing composition includes the following materials in parts by weight: pure acrylic emulsion 10-20 parts, expansive agent 1-5 parts, Portland cement 35-50 parts, silica fume 5-10 parts, and water 15-25 parts.

[0045] The compressive strength of the rock-fill concrete dam layer surface reinforcing composition can be increased by adding silica fume. For example, the compressive strength of the 42.5-grade Portland cement is about 42.5 MPa at 28 days. By adding a certain proportion of silica fume, the compressive strength of the rock-fill concrete dam layer surface reinforcing composition can be increased from 42.5 MPa to more than 50 MPa, such as 60 MPa or 70 MPa, thereby facilitating the increase of the compressive strength of the connection between the adjacent two sections of the rock-fill concrete dam.

[0046] The effects of the rock-fill concrete dam layer surface reinforcing composition provided by the embodiments of the present application are verified below in conjunction with Example Two.

[0047] In Example Two, the control experiments of Group 1 and Group 4 are performed.

[0048] In Group 1, the rock-fill concrete dam layer surface reinforcing composition is not provided between the adjacent two sections of the rock-fill concrete dam, and sample 1 is obtained by core drilling at the connection between the adjacent two sections of the rock-fill concrete dam (e.g., the upper surface of the lower section). The impermeability grade of sample 1 is detected by using a concrete impermeability instrument, and the ultimate shear strength of sample 1 is detected by using a direct shear instrument.

[0049] In Group 4, the rock-fill concrete dam layer surface reinforcing composition having a thickness of 2 cm is provided between the adjacent two sections of the rock-fill concrete dam, and the rock-fill concrete dam layer surface reinforcing composition includes the following materials in parts by weight: pure acrylic emulsion 20 parts, expansive agent 2 parts, Portland cement 50 parts, silica fume 10 parts, and water 20 parts. Sample 4 is obtained by core drilling at the connection between the adjacent two sections of the rock-fill concrete dam (e.g., the rock-fill concrete dam layer surface reinforcing composition). The impermeability grade of sample 4 is detected by using a concrete impermeability instrument, and the ultimate shear strength of sample 4 is detected by using a direct shear instrument.

[0050] Table 2 shows the impermeability grade and the ultimate shear strength of sample 1 and sample 4.

[0051] Table 2

[0052] Permeation resistance rating Ultimate shear strength / MPa Sample 1 W4 6.9 Sample 4 W6 11.26

[0053] As shown in Table 2, compared with sample 1 without the rockfill concrete dam layer surface reinforcing composition, the impermeability grade of sample 4 is improved from W4 to W6, and the ultimate shear strength is improved from 6.9 MPa to 11.26 MPa. Therefore, after increasing the proportion of silica fume, the shear strength is further improved.

[0054] According to still another embodiment of the present application, optionally, the rockfill concrete dam layer surface reinforcing composition can further include fly ash, and the weight of the fly ash is 5-10 parts. At this time, the weight of the Portland cement is further reduced to 35-50 parts. That is, the rockfill concrete dam layer surface reinforcing composition includes the following materials in the following weights: pure acrylic emulsion 10-20 parts, expansive agent 1-5 parts, Portland cement 35-50 parts, fly ash 5-10 parts, and water 15-25 parts.

[0055] The addition of fly ash can reduce the amount of Portland cement, and the hydration heat release of fly ash is less, which can reduce the hydration heat release of the rockfill concrete dam layer surface reinforcing composition, thus helping to reduce the temperature rise during construction and reduce cracks caused by temperature changes.

[0056] The effect of the rockfill concrete dam layer surface reinforcing composition provided by the embodiments of the present application is verified below in connection with Example Three.

[0057] In Example Three, the control experiments of the first group and the fifth group are taken.

[0058] The first group does not cover the rockfill concrete dam layer surface reinforcing composition between the adjacent two bin sections of the rockfill concrete dam, and core sampling is performed at the connection between the adjacent two bin sections of the rockfill concrete dam (such as the upper surface of the lower bin section) to obtain sample 1. The impermeability grade of sample 1 is detected by using a concrete impermeability instrument, and the ultimate shear strength of sample 1 is detected by using a direct shear instrument.

[0059] The fifth group covers 2 cm of the rockfill concrete dam layer surface reinforcing composition between the adjacent two bin sections of the rockfill concrete dam, and the rockfill concrete dam layer surface reinforcing composition includes the following materials in the following weights: pure acrylic emulsion 20 parts, expansive agent 2 parts, Portland cement 40 parts, fly ash 10 parts, and water 20 parts. Core sampling is performed at the connection between the adjacent two bin sections of the rockfill concrete dam (such as the rockfill concrete dam layer surface reinforcing composition) to obtain sample 5. The impermeability grade of sample 5 is detected by using a concrete impermeability instrument, and the ultimate shear strength of sample 5 is detected by using a direct shear instrument.

[0060] Table 3 shows the impermeability grade and the ultimate shear strength of sample 1 and sample 5.

[0061] Table 3

[0062] Permeation resistance rating Ultimate shear strength / MPa Sample 1 W4 6.9 Sample 5 W6 7.6

[0063] As shown in Table 3, compared with sample 1 without the rockfill concrete dam layer surface reinforcing composition, the impermeability grade of sample 5 is improved from W4 to W6, and the ultimate shear strength is also slightly improved from 6.9 MPa to 7.6 MPa. Therefore, after increasing the proportion of fly ash, the impermeability grade and shear strength can be improved to a certain extent even if the amount of Portland cement is appropriately reduced.

[0064] According to still another embodiment of the present application, optionally, the rockfill concrete dam layer surface reinforcing composition can further include silica fume and fly ash, and the weight parts of the silica fume and the fly ash are both 5-10 parts. At this time, the weight parts of the Portland cement are further reduced to 30-40 parts. That is, the rockfill concrete dam layer surface reinforcing composition includes the following weight parts of materials: 10-20 parts of pure acrylic emulsion, 1-5 parts of expanding agent, 30-40 parts of Portland cement, 5-10 parts of silica fume, 5-10 parts of fly ash, and 15-25 parts of water.

[0065] The effects of the rockfill concrete dam layer surface reinforcing composition provided by the embodiments of the present application are verified below in combination with Example Four and Example Five.

[0066] In Example Four, the control experiments of the first group and the sixth group are taken.

[0067] The first group does not cover the rockfill concrete dam layer surface reinforcing composition between the adjacent two bin sections of the rockfill concrete dam, and the core sampling is performed at the connection between the adjacent two bin sections of the rockfill concrete dam (such as the upper surface of the lower bin section) to obtain sample 1. The impermeability grade of sample 1 is detected by using a concrete impermeability instrument, and the ultimate shear strength of sample 1 is detected by using a direct shear instrument.

[0068] The sixth group covers 1 cm of the rockfill concrete dam layer surface reinforcing composition between the adjacent two bin sections of the rockfill concrete dam, and the rockfill concrete dam layer surface reinforcing composition includes the following weight parts of materials: 20 parts of pure acrylic emulsion, 5 parts of expanding agent, 40 parts of Portland cement, 10 parts of silica fume, 10 parts of fly ash, and 20 parts of water. The core sampling is performed at the connection between the adjacent two bin sections of the rockfill concrete dam (such as the rockfill concrete dam layer surface reinforcing composition) to obtain sample 6. The impermeability grade of sample 6 is detected by using a concrete impermeability instrument, and the ultimate shear strength of sample 6 is detected by using a direct shear instrument.

[0069] Table 4 shows the impermeability grade and the ultimate shear strength of sample 1 and sample 6.

[0070] Table 4

[0071] Permeation resistance rating Ultimate shear strength / MPa Sample 1 W4 6.9 Sample 6 W8 11.6

[0072] As shown in Table 4, compared with sample 1 without the rock-fill concrete dam layer surface reinforcing composition, the impermeability grade and the ultimate shear strength of sample 6 are greatly improved after the various materials in the rock-fill concrete dam layer surface reinforcing composition reach the maximum value, for example, the impermeability grade of sample 6 is improved from W4 to W8, and the ultimate shear strength of sample 6 is improved from 6.9 MPa to 11.6 MPa. Therefore, after increasing the proportion of silica fume and fly ash, it is beneficial to further improve the impermeability grade and the shear strength.

[0073] In Example Five, the control experiments of Group 1 and Group 7 are taken.

[0074] Group 1 does not cover the rock-fill concrete dam layer surface reinforcing composition between the adjacent two sections of the rock-fill concrete dam, core sampling is taken at the joint between the adjacent two sections of the rock-fill concrete dam (such as the upper surface of the lower section), sample 1 is obtained, the impermeability grade of sample 1 is detected by using the concrete impermeability instrument, and the ultimate shear strength of sample 1 is detected by using the direct shear instrument.

[0075] Group 7 covers 1 cm of the rock-fill concrete dam layer surface reinforcing composition between the adjacent two sections of the rock-fill concrete dam, the rock-fill concrete dam layer surface reinforcing composition includes the following materials in parts by weight: pure acrylic emulsion 10 parts, expansive agent 1 part, Portland cement 30 parts, silica fume 5 parts, fly ash 5 parts, and water 15 parts. Core sampling is taken at the joint between the adjacent two sections of the rock-fill concrete dam (such as the rock-fill concrete dam layer surface reinforcing composition), sample 7 is obtained, the impermeability grade of sample 7 is detected by using the concrete impermeability instrument, and the ultimate shear strength of sample 7 is detected by using the direct shear instrument.

[0076] Table 5 shows the impermeability grade and the ultimate shear strength of sample 1 and sample 7.

[0077] Table 5

[0078] Permeation resistance rating Ultimate shear strength / MPa Sample 1 W4 6.9 Sample 7 W4 7.6

[0079] As shown in Table 5, compared with sample 1 without the rock-fill concrete dam layer surface reinforcing composition, the impermeability grade of sample 7 can still reach W4 after the various materials in the rock-fill concrete dam layer surface reinforcing composition reach the minimum value, and the ultimate shear strength of sample 7 can be improved from 6.9 MPa to 7.6 MPa. Therefore, even if the various materials in the rock-fill concrete dam layer surface reinforcing composition reach the minimum value of the respective preset range, it is beneficial to improve the impermeability grade and / or the shear strength to a certain extent.

[0080] According to some embodiments of the present application, optionally, the expansive agent can include one of magnesium oxide, calcium oxide, or a composite of magnesium oxide and calcium oxide.

[0081] The magnesium oxide can generate magnesium hydroxide crystals by hydration to produce an expansion effect. The hydration product of magnesium oxide, magnesium hydroxide, has a fine flaky structure and is packed densely, which can improve the compactness of the rockfill concrete dam layer surface reinforcing composition, thereby compensating for the shrinkage of Portland cement, maintaining volume stability, and inhibiting cracking.

[0082] Calcium oxide is a strong alkaline substance, which reacts with water to release a large amount of heat and generate calcium hydroxide, while producing a large amount of gas (mainly hydrogen), forming bubbles and forming pores in the material, thereby playing a bulking effect.

[0083] Based on the rockfill concrete dam layer surface reinforcing composition provided in any of the above embodiments, the application further provides a rockfill concrete dam.

[0084] Figure 1 A structural schematic diagram of the rockfill concrete dam layer surface reinforcing composition provided in the embodiments of the application is shown in FIG. 1. As shown in FIG. 1, the rockfill concrete dam can include a plurality of bin sections 10 stacked along the height direction (e.g., the Z direction as shown in FIG. 1). Figure 1 As shown in FIG. 1, the rockfill concrete dam can include a plurality of bin sections 10 stacked along the height direction (e.g., the Z direction as shown in FIG. 1). Figure 1 For example, the rockfill concrete dam is shown by taking two bin sections 10 stacked along the height direction as an example. The height of each bin section 10 can be flexibly adjusted according to actual conditions, which is not limited in the application. For example, the height of each bin section 10 can be 1.5-3 meters. The number of bin sections 10 can also be flexibly adjusted according to the height of the rockfill concrete dam, which is not limited in the application. Figure 1 The rockfill concrete dam layer surface reinforcing composition 11 provided in any of the above embodiments is arranged between any two adjacent bin sections 10. The rockfill concrete dam layer surface reinforcing composition 11 can be arranged on the upper surface (or layer surface) a of the lower bin section 10 among the any two adjacent bin sections 10.

[0085] In this way, by arranging the rockfill concrete dam layer surface reinforcing composition between any two adjacent bin sections of the rockfill concrete dam, not only the impermeability of the rockfill concrete dam layer surface can be improved, but also the shear strength of the rockfill concrete dam layer surface can be improved, thereby solving the problems of poor impermeability and poor shear strength of the rockfill concrete dam layer surface, and providing quality assurance for the safe operation and maintenance of the rockfill concrete dam.

[0086] According to some embodiments of the application, the thickness of the rockfill concrete dam layer surface reinforcing composition arranged between any two adjacent bin sections can be 1-3 cm. The thickness of the rockfill concrete dam layer surface reinforcing composition can be flexibly adjusted according to actual conditions, which is not limited in the application.

[0087]

[0088] ​Based on the same technical concept of the rockfill concrete dam layer reinforcement composition and the rockfill concrete dam provided in any of the above embodiments, the present application also provides a construction method of the rockfill concrete dam layer reinforcement composition.

[0089] Based on the rock-fill concrete dam layer reinforcement composition provided in the above embodiments, the present application also provides a construction method of the rock-fill concrete dam layer reinforcement composition.

[0090] Figure 2 A schematic diagram of a construction method for a rockfill concrete dam layer reinforcement composition provided in an embodiment of the present application. Figure 2 As shown, the construction method of the rockfill concrete dam layer reinforcement composition provided in the embodiment of the present application may include the following steps S201 to S205.

[0091] S201: Forming the i-th section of the rockfill concrete dam by pouring concrete, where i is a positive integer.

[0092] The i-th compartment section of the rockfill concrete dam may be any compartment section of the rockfill concrete dam, for example, i may be equal to 1, 2 or other values.

[0093] Figure 3 This is a schematic diagram of the construction process of a rockfill concrete dam layer reinforcement composition. Figure 3 As shown, in S201, after laying rockfill of a preset height and pouring concrete, the i-th bin section 10 of the rockfill concrete dam is formed. In some embodiments, the proportion of rockfill with a particle size less than 300 mm can be less than or equal to 30%, and the proportion of rockfill with a particle size greater than 400 mm can be greater than 30%.

[0094] S202: After the concrete of the i-th bin section solidifies, clean the upper surface of the i-th bin section.

[0095] After the concrete of the i-th bin section solidifies, the upper surface (or layer) a of the i-th bin section can be cleaned by a cleaning device. For example, the cleaning device includes but is not limited to a fan or a water gun.

[0096] S203: After uniformly mixing the rockfill concrete dam layer reinforcement composition, apply it on the upper surface of the i-th bin section.

[0097] For example, the various materials in the rockfill concrete dam layer reinforcement composition can be uniformly mixed according to predetermined weights using a mixer. The uniformly mixed rockfill concrete dam layer reinforcement composition 11 is then applied to the upper surface a of the i-th bin section. Exemplary mixers include, but are not limited to, horizontal concrete mixers or mortar mixers. The rockfill concrete dam layer reinforcement composition can be any of the rockfill concrete dam layer reinforcement compositions described in the aforementioned embodiments.

[0098] S204: Film curing is performed on the rockfill concrete dam layer surface reinforcing composition overlaid on the upper surface of the i-th segment, and the film is removed after the curing time reaches a preset duration.

[0099] The film is overlaid on the rockfill concrete dam layer surface reinforcing composition 11 on the upper surface a of the i-th segment, and film curing is performed to reduce cracking of the rockfill concrete dam layer surface reinforcing composition due to rapid evaporation of moisture. The film is removed after the curing time reaches a preset duration. The preset duration can be flexibly adjusted according to actual conditions, which is not limited in the present application. Exemplarily, the preset duration can be 1-2 days, i.e. 24-48 hours.

[0100] S205: The above steps are cycled to perform construction of the i+1-th segment until the construction of the multiple segments of the rockfill concrete dam is completed.

[0101] After film curing, the construction of the i+1-th segment can be performed on the rockfill concrete dam layer surface reinforcing composition on the upper surface a of the i-th segment according to the same steps S201-S204 as the i-th segment until the construction of the multiple segments of the rockfill concrete dam is completed.

[0102] In this way, by overlaying the rockfill concrete dam layer surface reinforcing composition on the upper surface (or layer surface) of the i-th segment of the rockfill concrete dam, not only the impermeability of the rockfill concrete dam layer surface can be improved, but also the shear strength of the rockfill concrete dam layer surface can be improved, solving the problems of poor impermeability and poor shear strength of the rockfill concrete dam layer surface, thereby providing quality assurance for safe operation and maintenance of the rockfill concrete dam.

[0103] According to some embodiments of the present application, optionally, after the rockfill concrete dam layer surface reinforcing composition is uniformly mixed, S203: the rockfill concrete dam layer surface reinforcing composition is further overlaid on the upper surface of the i-th segment, further comprising the following steps:

[0104] After the rockfill concrete dam layer surface reinforcing composition is uniformly mixed, it is sprayed or brushed and overlaid on the upper surface of the i-th segment.

[0105] That is, after the rockfill concrete dam layer surface reinforcing composition is uniformly mixed, the uniformly mixed rockfill concrete dam layer surface reinforcing composition can be brushed and overlaid on the upper surface of the i-th segment. Of course, the uniformly mixed rockfill concrete dam layer surface reinforcing composition can also be sprayed and overlaid on the upper surface of the i-th segment by a spraying device, thereby improving the construction efficiency and shortening the construction time. Exemplarily, the spraying device includes but is not limited to a spraying machine.

[0106] According to some embodiments of the present application, optionally, after the rockfill concrete dam surface reinforcing composition is mixed evenly, S203: the rockfill concrete dam surface reinforcing composition is sprayed or brushed on the upper surface of the i th warehouse section, further comprising the following steps:

[0107] Spraying or brushing the rockfill concrete dam surface reinforcing composition with a thickness of 1-3 cm on the upper surface of the i th warehouse section.

[0108] In this way, the rockfill concrete dam surface reinforcing composition can completely cover the upper surface of the i th warehouse section, and the permeability resistance and shear strength of the rockfill concrete dam surface reinforcing composition are improved.

[0109] It should be understood that the structure and construction process of the rockfill concrete dam provided by the drawings of the embodiments of the present application are only some examples and are not used to limit the present application. In addition, the above-mentioned embodiments provided by the present application can be combined with each other in a non-contradictory manner.

[0110] It should be clear that each of the embodiments in the specification is described in a progressive manner, and the same or similar parts of each embodiment can be referred to each other, and each embodiment focuses on the difference from other embodiments. According to the above-described embodiments of the present application, these embodiments do not describe all the details and do not limit the present application to the specific embodiments described. Obviously, according to the above description, many modifications and changes can be made. The embodiments selected and described in the specification are to better explain the principles and practical applications of the present application, so that those skilled in the art can well utilize the present application and make modifications and uses on the basis of the present application. The present application is limited by the claims and their entire scope and equivalents.

[0111] Those skilled in the art should understand that the above-mentioned embodiments are exemplary and not limited. Different technical features appearing in different embodiments can be combined to achieve beneficial effects. Those skilled in the art can understand and implement other changed embodiments of the disclosed embodiments based on the drawings, the specification and the claims. In the claims, the term "comprising" does not exclude other structures; the number of "one" does not exclude multiple; the terms "first", "second" are used to mark the name and not to represent any specific order. Any reference signs in the claims should not be understood as limiting the scope of protection. The fact that certain technical features appear in different dependent claims does not mean that these technical features cannot be combined to achieve beneficial effects.

Claims

1. A rockfill concrete dam layer reinforcement composition, characterized in that: The invention comprises at least the following materials in parts by weight: 10 to 20 parts of pure acrylic emulsion, 1 to 5 parts of expansion agent, 40 to 60 parts of Portland cement and 15 to 25 parts of water.

2. The rockfill concrete dam surface reinforcement composition according to claim 1, characterized in that: It also includes silica fume or fly ash, which is 5 to 10 parts by weight; At this time, the weight of the Portland cement is further reduced to 35 to 50 parts.

3. The rockfill concrete dam surface reinforcement composition according to claim 1, characterized in that: It also includes silica fume and fly ash, wherein the weight portions of the silica fume and the fly ash are 5 to 10 parts each; At this time, the weight of the Portland cement is further reduced to 30 to 40 parts.

4. The rockfill concrete dam surface reinforcement composition according to claim 1, characterized in that: The expansion agent includes one of magnesium oxide, calcium oxide or a compound of magnesium oxide and calcium oxide.

5. A rockfill concrete dam comprising a plurality of bin sections stacked in a height direction, characterized in that: The rockfill concrete dam surface reinforcement composition according to any one of claims 1 to 4 is provided between any two adjacent bin sections, and the rockfill concrete dam surface reinforcement composition is covered on the upper surface of the lower bin section of any two adjacent bin sections.

6. The rockfill concrete dam according to claim 5, characterized in that: The thickness of the rockfill concrete dam surface reinforcement composition arranged between any two adjacent bin sections is 1 to 3 cm.

7. A construction method for a rockfill concrete dam layer reinforcement composition, characterized in that: include: The i-th section of the rockfill concrete dam is formed by pouring concrete, where i is a positive integer; After the concrete of the i-th bin section solidifies, clean the surface of the i-th bin section; Mixing the rockfill concrete dam surface reinforcement composition according to any one of claims 1 to 4 uniformly and applying the mixture on the upper surface of the i-th bin section; Performing film curing on the rockfill concrete dam surface reinforcement composition covered on the upper surface of the i-th bin section, and removing the film after the curing time reaches a preset time; The above steps are repeated to construct the i+1th bin section until the construction of multiple bin sections of the rockfill concrete dam is completed.

8. The construction method of the rockfill concrete dam surface reinforcement composition according to claim 7, characterized in that: After the rockfill concrete dam surface reinforcement composition is mixed evenly, it is covered on the upper surface of the i-th bin section, further comprising: After the rockfill concrete dam surface reinforcement composition is evenly mixed, it is sprayed or brushed onto the upper surface of the i-th bin section.

9. The construction method of the rockfill concrete dam surface reinforcement composition according to claim 8, characterized in that: After the rockfill concrete dam layer reinforcement composition is evenly mixed, it is sprayed or brushed onto the upper surface of the i-th bin section, further comprising: The rockfill concrete dam surface reinforcement composition is sprayed or painted on the upper surface of the i-th bin section with a thickness of 1 to 3 cm.

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