Inclined surface concrete pouring method for stable control of pre-buried diversion and shear-compression coupling

Abstract

The invention relates to a slope concrete pouring method for stable control of pre-buried diversion and shear-compression coupling. The slope concrete pouring method comprises the following steps: step 1, pre-burying a galvanized steel pipe in a first-stage bracket; secondly, first-stage bracket concrete pouring is conducted; thirdly, scabbling treatment is conducted on the contact face of the first-stage bracket concrete and the second-stage bracket concrete; fourthly, a second-stage bracket concrete formwork is constructed; and fifthly, a second-stage bracket concrete pouring and vibrating process is carried out. The method has the beneficial effects that concrete between different layers is vibrated through the vibrating rod, it is guaranteed that interfaces between the layers are fully fused, the cold seam or layering defect is avoided, the integrated strength of the whole structure is improved, and meanwhile through the low-pressure control technology of hopper customization, bin separation feeding, steel pipe flow guiding and directional vibrating, the construction efficiency is improved. Uniform pouring, compact vibration and forming quality are guaranteed; by constructing a control model, quantitative analysis is performed on the anti-floating stability of the galvanized steel pipe, and theoretical verification is performed on the anti-floating and anti-sliding structure of the galvanized steel pipe.

Description

Technical Field

[0001] The invention belongs to the technical field of corbel construction, and in particular relates to a slope concrete pouring method with pre-embedded diversion and shear-compression coupled stable control. Background Art

[0002] The radial gate corbel is an important load-bearing component supporting the gate arm. The quality of its concrete pouring directly affects the structural safety and long-term operational stability of hydraulic structures. In traditional construction techniques, the second-phase concrete is often poured by setting a pouring port at the upper end of the formwork and coarsely feeding it with a guide trough. However, due to the limited space and a certain inclination angle of the lower slope of the corbel, there are problems with the concrete being difficult to put into the silo and the coarse aggregate sliding and separating seriously. At the same time, since the vibrator is difficult to insert vertically or fit the slope, the vibration effect is limited, the local density of the concrete is insufficient, and quality defects such as honeycomb surface and voids are prone to occur.

[0003] These defects not only affect the structural quality and appearance, but also weaken the effective contact area between the bracket and the support arm, reducing its shear and compressive bearing capacity. Under multiple loads such as long-term head pressure, gate opening and closing vibrations, and temperature stress, they can easily induce stress concentration, microcrack expansion, and even structural instability, seriously threatening the operational safety of the gate system.

[0004] Therefore, optimizing the concrete pouring path and molding process in the sloped area, achieving directional concrete placement and efficient vibration within a small space, and ensuring the quality of the concrete molding on the sloped surface have become key technical challenges in the construction of radial gate bracket structures. Developing a patented method to address this issue and improve the construction quality and structural stability of the second phase of concrete construction has important engineering significance and practical value. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for pouring inclined concrete with pre-embedded diversion and shear-compression coupled stable control.

[0006] The method for pouring inclined concrete with pre-embedded diversion and shear-compression coupled stability control includes the following steps:

[0007] Step 1: Pre-embed the galvanized steel pipe in the first-phase corbel: After fixing the first-phase corbel to the gate pier, fix the two galvanized steel pipes in the first-phase corbel steel mesh through the fixed steel bars. The lower end of the galvanized steel pipe fits the inclined template of the first-phase corbel, and the upper end of the galvanized steel pipe extends out of the top of the first-phase corbel;

[0008] Step 2: First-stage corbel concrete pouring: pour the first-stage corbel concrete layer by layer in the first-stage corbel template. When pouring the first-stage corbel concrete of the upper layer, insert a vibrating rod into the first-stage corbel concrete of the lower layer and vibrate it.

[0009] Step 3: Roughening the contact surface between the first-stage corbel concrete and the second-stage corbel concrete: Roughen the first-stage corbel bevel template. After the chiseling is completed, remove the scum and dust and rinse the chiseled surface.

[0010] Step 4: Install the second-phase corbel concrete formwork: Fix the second-phase corbel concrete formwork and the first-phase corbel concrete through dowel bars and tension screws;

[0011] Step 5. Second-phase corbel concrete pouring and vibration process: The second-phase corbel concrete flows into the pouring funnel through the discharge funnel, and then is poured into the second-phase corbel concrete template through the pouring funnel. Two galvanized steel pipes are used alternately for the second-phase corbel concrete pouring and vibration.

[0012] Preferably, in step one, a groove is provided on the side wall of the first-phase corbel template, and the lower end of the galvanized steel pipe is beveled, and the bevel angle is consistent with the inclination angle of the side wall of the first-phase corbel template groove; the upper and lower ends of the galvanized steel pipe are wrapped with alkali-resistant geotextile and tied with galvanized iron wire; the top of the first-phase corbel template is provided with a buried position for the support hinge plate anchor bolt; before the galvanized steel pipe is buried, the center point position of the support hinge plate anchor bolt is measured so that a distance is left between the galvanized steel pipe and the support hinge plate anchor bolt; the fixed steel bars include U-shaped clamps and inverted V-shaped supporting structure steel bars; the steel mesh of the side wall of the first-phase corbel inclined template in the first-phase corbel groove is welded with a U-shaped clamp, and the two ends of the U-shaped clamp are welded to the steel mesh of the side wall of the first-phase corbel groove, and the lower end of the galvanized steel pipe is fixed in the U-shaped clamp; the upper end of the galvanized steel pipe is obliquely supported by two steel bars, the upper end of the steel bar is welded to the outer wall of the galvanized steel pipe, and the lower end of the steel bar is fixed on the steel mesh at the top of the first-phase corbel, and the two steel bars form an inverted V-shaped supporting structure.

[0013] As a preference, in step 1, a composite stability control model combining buoyancy, frictional resistance and the structure's own gravity is established, and the stability control coefficient λ is used for evaluation. The stability control coefficient expression for the galvanized steel pipe's anti-floating and anti-slip properties is:

[0014]

[0015] Where, k is the construction coefficient; A f is the bearing area of ​​the U-shaped clamp and the inverted V-shaped support structure steel bar; σ y is the yield strength of the inverted V-shaped support structure steel bars and U-shaped clamp steel bars; γ c is the concrete density; r is the inner radius of the galvanized steel pipe; h is the effective height of the galvanized steel pipe buried in the first-stage corbel concrete; μ is the friction coefficient between the galvanized steel pipe and the first-stage corbel concrete; d is the outer diameter of the galvanized steel pipe; ρ s is the material density of the galvanized steel pipe; r0, r i are the outer radius and inner radius of the galvanized steel pipe respectively; g is the acceleration due to gravity;

[0016] According to the value of λ, U-shaped clamps and inverted V-shaped supporting structural steel bars are used to clamp the galvanized steel pipe in the first-stage bracket.

[0017] Preferably, in step three, several equidistant dovetail-shaped shallow grooves are provided on the roughened surface; a friction shear stress model is established, and the functional relationship between the shear strength and the stress of the roughened surface is:

[0018] τ=c+σ n tanφ

[0019] Where, τ is the shear strength of the roughened surface; c is the adhesion of the roughened surface; σ n is the normal stress of the roughened surface; φ is the friction angle of the roughened surface.

[0020] Preferably, in step 4, a rubber strip is pasted between the second-phase corbel concrete formwork and the first-phase corbel concrete and the gate pier concrete; one end of the dowel is inserted into the first-phase corbel concrete, and the other end is extended out of the first-phase corbel concrete and welded with a U-shaped fixing ring; the opposite surfaces of the second-phase corbel concrete formwork are connected by a tension screw, and the tension screw and the U-shaped fixing ring are fixed; a stop grout strip is provided at the joint of the second-phase corbel concrete formwork to seal, and the tension screw is tightened until there is no grout leakage; the lateral horizontal load applied to the inner wall of the second-phase corbel concrete formwork by the second-phase corbel concrete from the free-falling state of the galvanized steel pipe is checked, and the expression is:

[0021]

[0022] Where σ h is the horizontal lateral pressure of the second-phase corbel concrete formwork; γ c is the weight of the second-stage corbel concrete; R is the radius of the lower end of the galvanized steel pipe; μ is the interface friction coefficient between the second-stage corbel concrete and the second-stage corbel concrete formwork; K is the lateral pressure diffusion coefficient.

[0023] Preferably, in step five, the discharge funnel is connected to the pouring funnel through a U-shaped steel bar, a funnel switch is provided at the bottom of the pouring funnel, and a height difference is provided between the bottom of the funnel switch and the top of the galvanized steel pipe; the amount of material discharged each time is controlled by the funnel switch; after the second-phase corbel concrete flows to the middle of the galvanized steel pipe, the material feeding is suspended and the pouring funnel is turned to the top of another galvanized steel pipe, and an inserted vibrating rod is inserted into the galvanized steel pipe for vibration at the same time; the two galvanized steel pipes are alternately filled with materials and vibrated.

[0024] As a preferred method, in step 5, the second-phase corbel concrete is poured into the second-phase corbel concrete module at a low pressure and a closed-loop model for on-site pouring control is established. First, the relationship between the viscous resistance and the driving pressure difference during the flow of the second-phase corbel concrete in the galvanized steel pipe is analyzed, and a safe feed rate function per unit time q is established, which is expressed as:

[0025]

[0026] Where, q is the volume of material passing through the galvanized steel pipe per unit time; r is the inner radius of the galvanized steel pipe; ΔP is the static pressure difference of the pouring funnel; η is the dynamic viscosity of the second-stage corbel concrete; L is the effective length of the galvanized steel pipe; ψ is the comprehensive resistance coefficient;

[0027] Secondly, the single discharge volume V of the pouring funnel is set with the q value as the upper limit dose and the release interval t, satisfying:

[0028]

[0029] Finally, the η parameter is corrected:

[0030]

[0031] Where η0 is the initial viscosity of the second-stage corbel concrete under standard conditions; T is the ambient temperature; α is the viscosity-temperature sensitivity coefficient; and T is the test reference temperature.

[0032] As a preferred method, in step five, a directional intubation vibration work density model is proposed, and the vibration work density expression is established:

[0033]

[0034] Where: W is the vibration input work density per unit volume of the second-stage corbel concrete; α is the vibration energy conversion coefficient; f is the vibrator frequency; A is the projected area of ​​the vibrating rod end; t is the single-point vibration time; V c is the volume of concrete within the vibration influence range;

[0035] V c Calculated by vibration radius:

[0036]

[0037] Where R is the effective action radius of the vibrator in the second-stage corbel concrete, and the empirical model is:

[0038] R=β·d

[0039] Where, d is the diameter of the vibrating rod; β is the empirical coefficient;

[0040] The spacing between galvanized steel pipes is obtained based on the directional pipe insertion vibration work density model.

[0041] As a preferred method, step 6 is further performed after step 5, i.e., shear-compression stress analysis and structural stability verification: the stress mode of the inclined concrete is calculated and analyzed, and compared with the shear strength of the contact surface to verify the actual normal stress per unit area of ​​the first-stage corbel slope σ n and the shear stress τ is:

[0042]

[0043] Where P is the total weight of the gate between the first-stage corbel and the gate pier, A is the casting area of ​​the inclined surface acting on the first-stage corbel, θ is the inclination angle of the inclined surface, σ n =τ, constituting a typical shear-compression coupled stress state;

[0044] Verify whether the shear stress is within the safe range and compare it with the shear strength of the first-stage bracket slope; the first-stage bracket slope shear strength calculated by the friction shear stress model is τ 界面 , the safety factor of the first-stage corbel slope is obtained as:

[0045]

[0046] The safety factor is higher than the value recommended by the specification, and the shear stress is within the safe range.

[0047] The beneficial effects of the present invention are:

[0048] 1) The present invention uses a vibrating rod to vibrate the concrete between different layers to ensure that the interfaces between the layers are fully integrated, avoid cold joints or delamination defects, and improve the integrated strength of the overall structure. At the same time, the low-pressure control process of "customized funnel + compartment feeding + steel pipe diversion + directional vibration" is used to ensure uniform pouring, dense vibration and molding quality.

[0049] 2) The present invention constructs a "composite buoyancy-friction-fluid pressure balance" control model to quantitatively analyze the anti-floating stability of galvanized steel pipes, and provides theoretical verification for the anti-floating and anti-slip structure of galvanized steel pipes.

[0050] 3) The present invention pre-buries a guide steel pipe in the initial construction stage to guide the concrete path and place it in a fixed position, thus solving the problems of uncontrolled material flow, blind vibration areas and quality defects in narrow slope areas caused by the traditional top pouring method.

[0051] 4) The galvanized steel pipe arrangement of the present invention adopts an upper and lower graded support structure, and stability analysis is performed based on the material buoyancy, sliding tendency and interface friction characteristics to ensure its reliable spatial positioning throughout the casting process.

[0052] 5) The concrete pouring of the present invention adopts quantitative low-pressure feeding combined with rhythm control and directional vibration, which effectively ensures controllable flow rate and dense molding.

[0053] 6) In order to improve the structural bonding strength, the present invention sets a geometric structure with an interlocking effect at the contact interface to enhance the shear bearing performance; the formwork system performs support design and node reinforcement based on the load distribution and deformation response during the pouring stage.

[0054] 7) The overall method of the present invention realizes multi-dimensional coordinated control of the concrete entry path, interface connection and structural stress, and has good adaptability and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 It is a construction process flow chart of the present invention;

[0056] Figure 2 This is a diagram of the first phase of corbel concrete pouring of the present invention;

[0057] Figure 3 This is the concrete pouring diagram of the first and second phase corbels of the present invention;

[0058] Figure 4 This is a cross-sectional view of the corbel position of the present invention;

[0059] Figure 5 It is the pouring funnel diagram of the present invention;

[0060] Figure 6 It is a feeding funnel diagram of the present invention.

[0061] Explanation of the accompanying symbols: first-phase corbel concrete 1, galvanized steel pipe 2, second-phase corbel concrete 3, hanging ear 4, corbel 5, switch control lever 6, funnel switch 7, discharge funnel 8, U-shaped steel bar 9. DETAILED DESCRIPTION

[0062] The present invention will be further described below with reference to the following examples. The following examples are provided only to facilitate understanding of the present invention. It should be noted that, without departing from the principles of the present invention, it is possible for a person skilled in the art to make various modifications to the present invention, and such improvements and modifications fall within the scope of the claims of the present invention.

[0063] Example 1

[0064] As an embodiment, a slope concrete pouring method with pre-embedded diversion and shear-compression coupled stable control is proposed, such as Figure 1-6 As shown, the following steps are included:

[0065] Step 1: Pre-embed the galvanized steel pipe 2 in the first-phase corbel: After fixing the first-phase corbel to the gate pier, fix the two galvanized steel pipes 2 in the first-phase corbel steel mesh through the fixed steel bars. The lower end of the galvanized steel pipe 2 fits the inclined template of the first-phase corbel, and the upper end of the galvanized steel pipe 2 extends out of the top of the first-phase corbel;

[0066] Specifically, a groove is provided on the side wall of the first-phase corbel formwork, and two galvanized steel pipes 2 with an outer diameter of Φ100mm and a wall thickness of ≥3mm are used as guide pipes. Their length is cut according to the actual height of the lower inclined surface of the corbel to ensure that the upper end of the steel pipe is not less than 200mm higher than the top surface of the first-phase concrete after installation; the lower end of the galvanized steel pipe 2 is beveled, and the bevel angle is consistent with the inclination angle of the side wall of the groove of the first-phase corbel formwork, which is controlled within the error range of ±2° to prevent installation dislocation and ensure structural tightness; the upper and lower ends of the galvanized steel pipe 2 are wrapped with alkali-resistant geotextile and tied with galvanized iron wire; the top of the first-phase corbel formwork is provided with a buried position for the support hinge plate anchor bolt; before burying the galvanized steel pipe 2, the center point position of the support hinge plate anchor bolt is measured to leave a distance between the galvanized steel pipe 2 and the support hinge plate anchor bolt; when laying out, it is necessary to ensure that the distance between the guide pipe and the support hinge plate anchor bolt is not less than 80mm, reserving sufficient operating space for subsequent concrete pouring and vibration operations;

[0067] The fixed steel bars include U-shaped clamps and inverted V-shaped supporting structure steel bars; the U-shaped clamps are welded to the steel mesh on the side wall of the inclined template of the first-stage corbel in the first-stage corbel groove, and the ends of the U-shaped clamps are welded to the steel mesh on the side wall of the first-stage corbel groove. The lower end of the galvanized steel pipe 2 is fixed in the U-shaped clamps; the upper end of the galvanized steel pipe 2 is obliquely supported by two steel bars, the upper end of the steel bars is welded to the outer wall of the galvanized steel pipe 2, and the lower end of the steel bars is fixed to the steel mesh at the top of the first-stage corbel. The two steel bars form an inverted V-shaped supporting structure;

[0068] Specifically, the lower end of the galvanized steel pipe 2 should be laid close to the inclined formwork of the corbel, and the pipe body should be arranged vertically along the normal direction of the formwork. In order to prevent it from floating or shifting during the concrete pouring process, a "double fixing structure" should be set to enhance stability:

[0069] Lower fixing method: Use φ12 steel bars to be cold-bent into U-shaped clamps, tie and spot-weld the two ends of the clamps to the steel mesh at the bottom of the corbel, and clamp the lower end of the galvanized steel pipe 2;

[0070] Upper reinforcement method: Set two φ10 short steel bars to obliquely support the upper end of the galvanized steel pipe 2. The upper end is welded to the outer wall of the galvanized steel pipe 2, and the lower end is fixed to the top steel mesh or formwork bracket to form an inverted V-shaped support structure, which effectively prevents the galvanized steel pipe 2 from deformation, displacement and vibration loosening;

[0071] Specifically, in order to ensure that the galvanized steel pipe 2 maintains stable spatial positioning during the concrete pouring process and avoid floating due to buoyancy or sliding disturbance due to material flow impact, a composite stability control model combining factors such as buoyancy, frictional resistance and the structure's own gravity was constructed to guide the mechanical design of the guide pipe fixed structure.

[0072] When the concrete is still fluid and unset, the galvanized steel pipe 2, submerged within it, will tend to float upward due to the upward buoyancy generated per unit volume of concrete. If this buoyancy exceeds the combined frictional resistance and self-weight of the galvanized steel pipe 2, the pipe will rise vertically, potentially causing deviation from the pre-set flow channel, disruption of the bottom formwork, or interface separation. Therefore, a quantitative analysis of its anti-floating stability is necessary, based on the force mechanism.

[0073] According to the principles of fluid mechanics, the total buoyancy force F on the galvanized steel pipe 2 is ↑ It can be expressed as:

[0074] F ↑ =γ c ·V i =γ c ·π·r 2 ·h

[0075] Where: γ c is the concrete density (kN / m 3 ); r is the inner radius of the diversion pipe (m); h is the effective height of the diversion pipe buried in the concrete (m);

[0076] In contrast, the sliding resistance of the galvanized steel pipe 2 in the concrete mainly comes from the friction between its outer wall and the concrete, as well as the weight of the pipe. μ It can be estimated as:

[0077] F μ =μ·γ c ·h·π·d

[0078] Where: μ is the friction coefficient between the galvanized steel pipe 2 and the concrete; d is the outer diameter of the galvanized steel pipe 2 (m); the other symbols are the same as above;

[0079] Galvanized steel pipe 2 weight G s Expressed as:

[0080]

[0081] Where: s The material density of galvanized steel pipe 2 (kg / m 3 ); r0, r i are the outer radius and inner radius of the galvanized steel pipe 2 (m); g is the acceleration due to gravity (9.81m / s 2 );

[0082] The above three forces are coupled to construct the total floating driving force:

[0083] F result =F ↑ -F μ -G s

[0084] In order to ensure the stability of the galvanized steel pipe 2 during the concrete pouring process, it is necessary to design a fixed structure of V-shaped steel bracing + U-shaped clamp to provide anti-floating and anti-slip restraint. The safety design criterion is expressed as follows:

[0085]

[0086] Among them: F fix is the maximum bearing capacity that the fixing device can bear, which is determined by the bearing area A of the fixed steel bar. f , yield strength σ y It is determined together with the construction coefficient k; the construction coefficient k is a correction coefficient that comprehensively considers factors such as the fixed structure node form, force mode, weld type, and actual force conversion path. It is usually determined through finite element simulation verification, structural testing, or reference to engineering experience values.

[0087] The hybrid connection structure of V-shaped steel bar diagonal brace + U-shaped clamp is simplified and modeled with reference to the "Code for Construction of Reinforced Concrete Structures" and test data of typical engineering nodes. The construction coefficient range is 1.1-1.3. It adopts welding connection, diagonal brace embedding and structural reinforcement. The upper limit of 1.3 is recommended. When solving the specific problem, the equivalent stiffness analysis of the support system or the following simplified expression can also be used for approximate estimation:

[0088]

[0089] In summary, the stability control coefficient expression of galvanized steel pipe 2 against floating and sliding is:

[0090]

[0091] To ensure that the galvanized steel pipe 2 has sufficient resistance to floating and sliding during the concrete pouring process, a stability control coefficient λ is used for quantitative assessment. According to technical standards such as the "Code for Loads on Building Structures" (GB 50009) and the "Code for Acceptance of Construction Quality of Concrete Structures" (GB 50204), a structural safety factor of 1.5 or above is recommended. Based on the value of λ, a U-shaped clamp and inverted V-shaped supporting structural steel bars are designed to secure the galvanized steel pipe 2 in the first-stage bracket.

[0092] Step 2, pouring the first-stage corbel concrete 1: pouring the first-stage corbel concrete 1 layer by layer in the first-stage corbel template. When pouring the first-stage corbel concrete 1 of the upper layer, insert a vibrating rod into the first-stage corbel concrete 1 of the lower layer for vibrating.

[0093] Specifically, after the galvanized steel pipe 2 was embedded, the hinge anchor bolts were laid, and the first-phase corbel concrete 1 formwork was installed and passed the reinforcement acceptance, the pouring of the first-phase corbel concrete 1 was started. C35 fine stone concrete was used, and the slump was controlled within the range of 16cm±2cm to ensure good fluidity and molding quality.

[0094] The construction process of "layered and segmented, layer-by-layer pouring" is adopted, with the thickness of each layer controlled at 30-40cm and the construction interval between layers not exceeding 1 hour. When pouring the upper layer of concrete, the vibrator is inserted 5cm into the lower layer of concrete to ensure full fusion of the inter-layer interface, avoid cold joints or delamination defects, and improve the integrated strength of the overall structure.

[0095] The pre-buried galvanized steel pipe 2 is in the flowing concrete and is subjected to a large buoyancy. Especially when the concrete is highly fluid and the pouring speed is fast, the galvanized steel pipe 2 is very likely to float up, which will not only destroy its original channel angle and spatial position, but may also cause the concrete pouring to be offset, the density to be insufficient, and even the anchor bolt positioning error, which will seriously affect the subsequent slope construction accuracy and structural performance.

[0096] To this end, a quantitative analysis of the buoyancy experienced by the galvanized steel pipe 2 in a liquid environment is required before concrete is poured, and based on this analysis, an anti-floating fixture that meets the structural safety factor requirements is designed. Buoyancy calculations are based on the uplift force generated by the volume displaced by the galvanized steel pipe 2 in the unhardened concrete and the difference in material density. This is estimated based on the pipe's dimensional parameters and actual burial depth. This serves as the basis for subsequent stability design. Buoyancy can be estimated based on the force per unit volume:

[0097] F b =γ c V = γ c ·πr 2 ·h

[0098] Among them, γ c is the concrete density (kN / m 3 ), r is the inner radius of the galvanized steel pipe 2, and h is the effective length of the galvanized steel pipe 2 effectively buried.

[0099] Calculation results show that each galvanized steel pipe (2) experiences significant buoyancy in concrete. To ensure stability, the anti-buoyancy structure should possess a resistance capacity of at least 1.5 times that force. The following fixing strategy is recommended: The lower end of the galvanized steel pipe (2) is spot-welded to the first-phase corbel inclined formwork reinforcement mesh using U-shaped steel clamps. An inverted V-shaped short steel support is installed above, welded diagonally between the end of the galvanized steel pipe (2) and the top layer of main reinforcement, forming a triangular rigid structure that provides both horizontal and vertical restraint.

[0100] Before pouring, check the firmness of each galvanized steel pipe 2 fixed node one by one to confirm that the weld is stable, without shaking or looseness. At the same time, mark the initial elevation on the galvanized steel pipe 2 so that it can be observed in real time during the construction process whether it is displaced.

[0101] This anti-floating design not only provides a quantifiable basis for controlling structural stability, but also significantly reduces engineering risks such as voids, grouting failures, and anchor displacement caused by steel pipe displacement, thereby comprehensively improving the controllability and reliability of the construction process.

[0102] During the construction process, a dedicated person should be responsible for the vibration operation, especially in the area near the galvanized steel pipe 2 and the anchor bolt. The insertion depth and operating angle of the vibrator must be strictly controlled. It is strictly forbidden for the vibrator to directly contact the galvanized steel pipe 2 to prevent it from being disturbed, deflected, damaged, or concrete slurry from seeping into the galvanized steel pipe 2.

[0103] After the concrete is poured and finished, the top surface elevation should be checked with a level to ensure that it is consistent with the design elevation; compaction, leveling and finishing should be completed manually before final setting, and after final setting, it should be immediately covered with wet burlap and watered for maintenance. The maintenance period should be no less than 7 days to ensure the strength and surface quality of the concrete.

[0104] Step 3: Chiseling the contact surface between the first-stage corbel concrete 1 and the second-stage corbel concrete 3: Chisel the first-stage corbel bevel template, remove scum and dust after chiseling, and rinse the chiseled surface;

[0105] Step 4: Install the second phase corbel concrete 3 formwork: Fix the second phase corbel concrete 3 formwork and the first phase corbel concrete 1 with dowel bars and tension screws;

[0106] Step 5, second phase corbel concrete 3 pouring and vibration process: the second phase corbel concrete 3 flows into the pouring funnel through the discharge funnel 8, and then is poured into the second phase corbel concrete 3 template through the pouring funnel. The two galvanized steel pipes 2 are alternately used for the second phase corbel concrete 3 pouring and vibration.

[0107] Example 2

[0108] As another embodiment, this embodiment 2 proposes, based on the embodiment 1, a more specific method for pouring slope concrete with pre-embedded diversion and shear-compression coupled stable control, such as Figure 1-6 As shown, the following steps are included:

[0109] Step 1: Pre-embed the galvanized steel pipe 2 in the first-phase corbel: After fixing the first-phase corbel to the gate pier, fix the two galvanized steel pipes 2 in the first-phase corbel steel mesh through the fixed steel bars. The lower end of the galvanized steel pipe 2 fits the inclined template of the first-phase corbel, and the upper end of the galvanized steel pipe 2 extends out of the top of the first-phase corbel;

[0110] Step 2, pouring the first-stage corbel concrete 1: pouring the first-stage corbel concrete 1 layer by layer in the first-stage corbel template. When pouring the first-stage corbel concrete 1 of the upper layer, insert a vibrating rod into the first-stage corbel concrete 1 of the lower layer for vibrating.

[0111] Specifically, after the galvanized steel pipe 2 was embedded, the hinge anchor bolts were laid, and the first-phase corbel concrete 1 formwork was installed and passed the reinforcement acceptance, the pouring of the first-phase corbel concrete 1 was started. C35 fine stone concrete was used, and the slump was controlled within the range of 16cm±2cm to ensure good fluidity and molding quality.

[0112] The construction process of "layered and segmented, layer-by-layer pouring" is adopted, with the thickness of each layer controlled at 30-40cm and the construction interval between layers not exceeding 1 hour. When pouring the upper layer of concrete, the vibrator is inserted 5cm into the lower layer of concrete to ensure full fusion of the inter-layer interface, avoid cold joints or delamination defects, and improve the integrated strength of the overall structure.

[0113] The pre-buried galvanized steel pipe 2 is in the flowing concrete and is subjected to a large buoyancy. Especially when the concrete is highly fluid and the pouring speed is fast, the galvanized steel pipe 2 is very likely to float up, which will not only destroy its original channel angle and spatial position, but may also cause the concrete pouring to be offset, the density to be insufficient, and even the anchor bolt positioning error, which will seriously affect the subsequent slope construction accuracy and structural performance.

[0114] To this end, a quantitative analysis of the buoyancy experienced by the galvanized steel pipe 2 in a liquid environment is required before concrete is poured, and based on this analysis, an anti-floating fixture that meets the structural safety factor requirements is designed. Buoyancy calculations are based on the uplift force generated by the volume displaced by the galvanized steel pipe 2 in the unhardened concrete and the difference in material density. This is estimated based on the pipe's dimensional parameters and actual burial depth. This serves as the basis for subsequent stability design. Buoyancy can be estimated based on the force per unit volume:

[0115] F b =γ c V = γ c ·πr 2 ·h

[0116] Among them, γ c is the concrete density (kN / m 3 ), r is the inner radius of the galvanized steel pipe 2, and h is the effective length of the galvanized steel pipe 2 effectively buried.

[0117] Calculation results show that each galvanized steel pipe (2) experiences significant buoyancy in concrete. To ensure stability, the anti-buoyancy structure should possess a resistance capacity of at least 1.5 times that force. The following fixing strategy is recommended: The lower end of the galvanized steel pipe (2) is spot-welded to the first-phase corbel inclined formwork reinforcement mesh using U-shaped steel clamps. An inverted V-shaped short steel support is installed above, welded diagonally between the end of the galvanized steel pipe (2) and the top layer of main reinforcement, forming a triangular rigid structure that provides both horizontal and vertical restraint.

[0118] Before pouring, check the firmness of each galvanized steel pipe 2 fixed node one by one to confirm that the weld is stable, without shaking or looseness. At the same time, mark the initial elevation on the galvanized steel pipe 2 so that it can be observed in real time during the construction process whether it is displaced.

[0119] This anti-floating design not only provides a quantifiable basis for controlling structural stability, but also significantly reduces engineering risks such as voids, grouting failures, and anchor displacement caused by steel pipe displacement, thereby comprehensively improving the controllability and reliability of the construction process.

[0120] During the construction process, a dedicated person should be responsible for the vibration operation, especially in the area near the galvanized steel pipe 2 and the anchor bolt. The insertion depth and operating angle of the vibrator must be strictly controlled. It is strictly forbidden for the vibrator to directly contact the galvanized steel pipe 2 to prevent it from being disturbed, deflected, damaged, or concrete slurry from seeping into the galvanized steel pipe 2.

[0121] After the concrete is poured and finished, the top surface elevation should be checked with a level to ensure it is consistent with the design elevation. Before final setting, compaction, leveling, and finishing should be completed manually. After final setting, the concrete should be immediately covered with wet sacks and watered for curing. The curing period should be no less than 7 days to ensure the strength and surface quality of the concrete.

[0122] Step 3: Chiseling the contact surface between the first-stage corbel concrete 1 and the second-stage corbel concrete 3: Chisel the first-stage corbel bevel template, remove scum and dust after chiseling, and rinse the chiseled surface;

[0123] Step 4: Install the second phase corbel concrete 3 formwork: Fix the second phase corbel concrete 3 formwork and the first phase corbel concrete 1 with dowel bars and tension screws;

[0124] Step 5, second phase corbel concrete 3 pouring and vibration process: the second phase corbel concrete 3 flows into the pouring funnel through the discharge funnel 8, and then is poured into the second phase corbel concrete 3 template through the pouring funnel. The two galvanized steel pipes 2 are alternately used for the second phase corbel concrete 3 pouring and vibration.

[0125] It should be noted that the parts in this embodiment that are the same or similar to those in the first embodiment can be referenced to each other and will not be described in detail in this application.

[0126] Example 3

[0127] As another embodiment, this embodiment 3 proposes, based on the embodiment 2, a more specific method for pouring slope concrete with pre-embedded diversion and shear-compression coupled stable control, such as Figure 1-6 As shown, the following steps are included:

[0128] Step 1: Pre-embed the galvanized steel pipe 2 in the first-phase corbel: After fixing the first-phase corbel to the gate pier, fix the two galvanized steel pipes 2 in the first-phase corbel steel mesh through the fixed steel bars. The lower end of the galvanized steel pipe 2 fits the inclined template of the first-phase corbel, and the upper end of the galvanized steel pipe 2 extends out of the top of the first-phase corbel;

[0129] Step 2, pouring the first-stage corbel concrete 1: pouring the first-stage corbel concrete 1 layer by layer in the first-stage corbel template. When pouring the first-stage corbel concrete 1 of the upper layer, insert a vibrating rod into the first-stage corbel concrete 1 of the lower layer for vibrating.

[0130] Step 3: Chiseling the contact surface between the first-stage corbel concrete 1 and the second-stage corbel concrete 3: Chisel the first-stage corbel bevel template, remove scum and dust after chiseling, and rinse the chiseled surface;

[0131] Specifically, when the strength of the first-phase concrete reaches more than 70% of the design value, the roughening operation of the contact interface with the second-phase concrete can be carried out; this interface area includes the top surface of the corbel, the side edge and the contact area with the inclined formwork, which is the key influencing area for the subsequent structural bonding performance.

[0132] Before roughening, the interface boundary line should be laid out and accurately marked according to the construction drawings; the boundary treatment should be strictly controlled within the design line position to avoid cross-border operations that may cause structural linear damage, increased carbonization risk or weakening of mechanical properties, to ensure appearance quality and durability.

[0133] During the construction of the radial gate bracket slope, the contact interface is located in the stress-bearing area of ​​the slope and is subjected to the combined effects of the structural self-weight decomposition force and the dynamic load of opening and closing for a long time. If the interface bond is not strong, it is very easy to cause cracking and slippage, and in severe cases, it can lead to the overall instability of the slope. Therefore, improving the overall structural stability by enhancing the shear bearing capacity of the interface is the core link to ensure the safety of subsequent operation; the chiseling depth should be controlled at 5-8mm, with 1 / 3 of the concrete coarse aggregate exposed. After the chiseling is completed, the slag and dust must be removed and the surface must be thoroughly rinsed with a high-pressure water gun to ensure the quality of the subsequent pouring. The chiseling method is carried out in different areas: an electric impact drill is used in conjunction with a hand hammer for precise operation in the edge area within 30mm of the boundary line; a small jackhammer is used for mechanized construction in the large area in the middle.

[0134] To verify the interface shear resistance, a force decomposition analysis of the shear stress state of the contact surface was performed, and a functional relationship between shear strength and interface stress was established. This relationship takes into account the effects of interface bonding properties, compressive state, and interface roughness, and its expression is as follows:

[0135] τ=c+σ n tanφ

[0136] Where, τ is the interface shear strength (MPa); c is the concrete interface bond strength (MPa); σ n is the interface normal stress (MPa); φ is the concrete interface friction angle (°);

[0137] Calculations show that the interface already has basic shear resistance based on conventional roughening.

[0138] However, to enhance the structure's fatigue resistance and resistance to sudden slip under long-term dynamic loads, six equidistant shallow "dovetail" grooves (each 5 cm wide and 2 cm deep) were further provided on the contact surface. Their structure resembles gear meshing and provides additional mechanical engagement force. This force can be estimated as follows:

[0139] F 键合 =n·b·H·τ c

[0140] Where n = 6 is the number of grooves; b = 0.05m is the groove width; H = 0.02m is the groove depth; τ c is the shear bond strength of concrete (MPa);

[0141] The mechanical bite force is distributed to the contact area A (m 2 ) can be converted into effective shear stress increase value:

[0142]

[0143] The total shear capacity of the interface is thus increased to:

[0144] τ 总 =τ+Δτ

[0145] Although the numerical improvement is limited, the mechanical interlocking structure has a very strong "limited anti-slip" function, and its actual anti-disturbance effect is far greater than the estimated bonding strength. At the same time, after the grooves are set, the shear force no longer acts solely on the interface, but is converted into a tensile failure mechanism of the tooth-shaped nested structure, which improves the overall plasticity and toughness of the interface and significantly improves the fatigue life of the structure. During construction, a jackhammer should be used to accurately chisel the contact surface, and boundary line control technology should be used to define the treatment range. The grooves need to be evenly distributed to avoid concentrated stress areas; after chiseling, the interface should be cleaned with high-pressure water to ensure that there is no slurry residue in the groove body, providing good conditions for the subsequent "secondary growth" of concrete.

[0146] Then, remove the geotextile at the bottom of the galvanized steel pipe 2 and clean the residue inside the pipe. Remove the geotextile at the top just before the template is closed to prevent debris from falling into the warehouse.

[0147] Step 4: Install the second phase corbel concrete 3 formwork: Fix the second phase corbel concrete 3 formwork and the first phase corbel concrete 1 with dowel bars and tension screws;

[0148] Specifically, after completing the roughening treatment of the contact surface between the first-phase corbel concrete 1 and the second-phase corbel concrete 3, the construction of embedded parts such as the support and hinge seat plate, and passing the relevant process acceptance, the installation of the formwork system in the pouring area of ​​the second-phase corbel concrete 3 can be started.

[0149] The formwork for this phase will be 1.8cm thick, high-strength bamboo plywood. 5mm thick sponge strips will be applied to the areas where the formwork contacts the existing concrete, such as the first-phase corbel concrete and the pier structure, to effectively seal the joints and prevent defects such as leakage and misalignment during the concrete pouring process.

[0150] The formwork structure utilizes a combination of single-sided formwork, bidirectional dowel rods, and tension rods. The dowel rods are pre-welded with U-shaped retaining rings and drawn from the concrete of the corbel or gate pier. They are connected to the tension rods through the formwork deck, forming a complete rigid support framework. The formwork is sealed on the longitudinal, transverse, and bottom sides, with stoppers installed at the joints. The rods are tightened until there is no leakage, forming a closed load-bearing unit that meets the construction requirements of pressure resistance, vibration resistance, and no leakage.

[0151] To ensure the safety and stability of the formwork system during concrete pouring and vibration operations, a combined mechanical evaluation of its bearing capacity, stiffness, and stability was required. The Jansen theory was used to calculate the maximum lateral static pressure that the second-stage corbel concrete 3 formwork could withstand. This theory is based on the lateral horizontal load exerted on the inner wall of the second-stage corbel concrete 3 formwork by concrete freely falling from a vertical channel such as the galvanized steel pipe 2. The formula is as follows:

[0152]

[0153] Where σ h is the horizontal lateral pressure of the second phase corbel concrete 3 formwork (kPa); γ c is the concrete density (kN / m 3 ); R is the radius of the funnel and the pouring port (m); μ is the interface friction coefficient between concrete and formwork; K is the lateral pressure diffusion coefficient.

[0154] This value represents the maximum static pressure that the local area of ​​the Phase II corbel concrete formwork can withstand during the pouring process. Considering the dynamic disturbance caused by concrete vibration, the formwork structure must be designed to withstand a peak lateral pressure no less than this to prevent failure risks such as bulging, instability, or grouting.

[0155] The formwork support should be structurally checked according to the above loads to ensure sufficient strength, rigidity and anti-slip ability. In particular, the side wall area of ​​the formwork should be equipped with reinforcing slats, limit blocks and temporary supports to resist local slippage and lateral deformation.

[0156] During the construction process, in order to prevent excessive local impact force from causing overpressure and instability of the second-phase corbel concrete 3 formwork, a control strategy of "segmented feeding and speed-limited pouring" should be adopted; a special homemade funnel should be used to pour concrete in a quantitative manner, and each feeding should be controlled within the range of 5-8L, and the filling process at the lower end of the galvanized steel pipe 2 should be ensured to be smooth to prevent high-speed impact on the formwork from causing local stress peaks.

[0157] In addition, the vibration operation must be highly coordinated with the pouring rhythm to avoid concentrated material discharge and high-frequency vibration in local areas of the formwork, which may cause instantaneous overpressure. Before pouring, all nodes of the formwork reinforcement system must be fully reviewed to confirm that all bolts are tightened, joints are sealed without leakage, and the support structure is not loose, to ensure the structural stability and sealing of the formwork system throughout the construction process.

[0158] Step 5, second phase corbel concrete 3 pouring and vibration process: the second phase corbel concrete 3 flows into the pouring funnel through the discharge funnel 8, and then is poured into the second phase corbel concrete 3 template through the pouring funnel. The two galvanized steel pipes 2 are alternately used for the second phase corbel concrete 3 pouring and vibration.

[0159] It should be noted that the parts in this embodiment that are the same or similar to those in the second embodiment can be referenced to each other and will not be described in detail in this application.

[0160] Example 4

[0161] As another embodiment, this fourth embodiment proposes, based on the third embodiment, a more specific method for pouring slope concrete with pre-embedded diversion and shear-compression coupled stable control, such as Figure 1-6 As shown, the following steps are included:

[0162] Step 1: Pre-embed the galvanized steel pipe 2 in the first-phase corbel: After fixing the first-phase corbel to the gate pier, fix the two galvanized steel pipes 2 in the first-phase corbel steel mesh through the fixed steel bars. The lower end of the galvanized steel pipe 2 fits the inclined template of the first-phase corbel, and the upper end of the galvanized steel pipe 2 extends out of the top of the first-phase corbel;

[0163] Step 2, pouring the first-stage corbel concrete 1: pouring the first-stage corbel concrete 1 layer by layer in the first-stage corbel template. When pouring the first-stage corbel concrete 1 of the upper layer, insert a vibrating rod into the first-stage corbel concrete 1 of the lower layer for vibrating.

[0164] Step 3: Chiseling the contact surface between the first-stage corbel concrete 1 and the second-stage corbel concrete 3: Chisel the first-stage corbel bevel template, remove scum and dust after chiseling, and rinse the chiseled surface;

[0165] Step 4: Install the second phase corbel concrete 3 formwork: Fix the second phase corbel concrete 3 formwork and the first phase corbel concrete 1 with dowel bars and tension screws;

[0166] Step 5, second phase corbel concrete 3 pouring and vibrating process: the second phase corbel concrete 3 flows into the pouring funnel through the discharge funnel 8, and then is poured into the second phase corbel concrete 3 template through the pouring funnel. The two galvanized steel pipes 2 are alternately used for the second phase corbel concrete 3 pouring and vibrating;

[0167] Specifically, during the pouring of the second-phase slope concrete, in order to ensure that the concrete can be stably and smoothly introduced into the second-phase corbel concrete 3 template through the pre-buried galvanized steel pipe 2, it is necessary to conduct a mechanical analysis of the stability of the galvanized steel pipe 2 in a vertical or inclined state, especially to prevent it from axial slippage or sinking due to static pressure during the pouring process.

[0168] If improperly controlled, when concrete enters the galvanized steel pipe 2 from the hopper, the static pressure generated by its own weight may cause the galvanized steel pipe 2 to slide down as a whole, thereby impacting the bottom formwork structure or disturbing the lower embedded components, affecting the structural positioning accuracy and the stability of the pouring quality.

[0169] To avoid this problem, it is necessary to analyze the anti-slip ability of the galvanized steel pipe 2 in the pouring state and calculate the interface friction resistance it can provide. The expression is as follows:

[0170] F 摩阻 =μ·γ c ·h·πd

[0171] Where μ is the friction coefficient between the galvanized steel pipe 2 and the concrete; γ c is the concrete density (kN / m 3 ); h is the effective height of concrete in the pipe (m); d is the inner diameter of the pipe (m);

[0172] The friction resistance value represents the maximum static pressure that the galvanized steel pipe 2 can withstand during the pouring process.

[0173] If the upper concrete pouring pressure exceeds this value, there is a risk of slippage of the galvanized steel pipe 2. To ensure safety, the following measures are taken: the discharge volume is controlled within a reasonable range of 5-8L each time; the height difference between the lower opening of the funnel and the upper opening of the galvanized steel pipe 2 is maintained at no more than 30cm; the outer wall of the galvanized steel pipe 2 is appropriately polished to improve surface roughness and enhance frictional resistance; an elevation control line is set, and a dedicated person is assigned to monitor the displacement of the galvanized steel pipe 2. If slippage is detected, pouring is stopped immediately and the position is readjusted; a triangular support structure formed by welding short steel bars to the main bars is installed at the upper opening to enhance overall anti-slip capabilities.

[0174] Considering the small volume of the second phase slope concrete (generally no more than 1.5m 3 ), complex structures, and limited space. Using conventional pumps and pipes for high-pressure delivery can easily cause impact damage to the formwork, disturb bolts, and waste concrete, posing significant construction risks. This patent proposes a low-pressure control process using a "customized funnel + compartment feeding + steel pipe diversion + directional vibration" to ensure uniform pouring, compaction, and high-quality molding.

[0175] The specific process flow is as follows: a stainless steel pouring funnel with an upper opening size of 40cm×40cm and a lower opening diameter of Φ10cm is used, and the lower part of the pouring funnel is kept unobstructed and connected with the concrete pouring area; concrete is quantitatively injected into the funnel through the tower crane bucket, and driven by gravity, it slowly descends along the galvanized steel pipe 2 to the target position of the first-phase corbel concrete 1 module.

[0176] To effectively control the flow rate of concrete during pouring and prevent aggregate separation, flow stratification, or local pipe blockage caused by excessive velocity, the present invention establishes a flow relationship expression for estimating conductivity by combining factors such as pipe diameter, fluid viscosity, pressure difference, and pipe length.

[0177] This method can be used to predict the volume flow rate of concrete passing through the galvanized steel pipe 2 per unit time, guiding the actual feeding frequency and rhythm control, thereby achieving a safe and stable silo process. Its flow capacity can be estimated by referring to the following volume flow rate expression:

[0178]

[0179] Where Q is the volume flow rate (m 3 / s); r is the inner radius of the galvanized steel pipe 2 (m); ΔP is the static pressure at the hopper outlet (kPa); μ is the dynamic viscosity of concrete (Pa·s); L is the effective length of the galvanized steel pipe 2 (m); and the maximum controllable flow rate is calculated.

[0180] According to model calculations and actual construction, the amount of material added each time is controlled at 5-8L, and the "feeding-pause-vibration" alternating operation process is implemented to prevent the material from being piled too high or the diversion path from being unstable.

[0181] After the concrete flows to the middle of the pipe, the feeding is immediately stopped and the funnel is transferred to the second opening of another galvanized steel pipe. At the same time, an inserted vibrating rod is inserted from the upper opening for vertical fixed-point vibration.

[0182] The diameter of the vibrating rod should be ≥10mm smaller than the pipe diameter to avoid obstruction in the pipe. Two galvanized steel pipes should be filled and vibrated alternately to avoid blind spots or repeated vibration.

[0183] In order to further optimize the vibration coverage, the vibration radius is estimated based on the following empirical model:

[0184] R=k·D

[0185] Where R is the vibration radius (m), D is the diameter of the vibrating rod (m), and k is the empirical coefficient;

[0186] Therefore, it is determined that the spacing between the galvanized steel pipes 2 should be no less than 0.8m to ensure that the vibration area is fully covered; a dedicated person should monitor the status of the steel pipes, the stability of the funnel suspension and the feeding rhythm throughout the construction process, focusing on checking whether there are any abnormal conditions such as loose steel pipes, backflow, blockage, etc., and make timely adjustments to ensure the safety and quality of the pouring;

[0187] Furthermore, the second-phase corbel concrete 3 is poured into the second-phase corbel concrete 3 module at a quantitative low pressure, and a closed-loop model for on-site pouring control is established. First, the relationship between the viscous resistance and the driving pressure difference during the flow of the second-phase corbel concrete 3 in the galvanized steel pipe 2 is analyzed, and the safe feeding quantity function per unit time q is established, which is expressed as:

[0188]

[0189] Where q is the volume of material passing through the galvanized steel pipe 2 per unit time; r is the inner radius of the galvanized steel pipe 2; ΔP is the static pressure difference of the pouring funnel; η is the dynamic viscosity of the second-phase corbel concrete 3; L is the effective length of the galvanized steel pipe 2; ψ is the comprehensive resistance coefficient; ψ is a functional relationship term formed by the following two factors:

[0190] ψ=a+bθ+cε+dθ 2 +eε 2 +fθε

[0191] ε is the roughness coefficient of the inner wall of the galvanized steel pipe 2 (mm), which is determined by filling with standard sandpaper;

[0192] θ is the inclination angle of the galvanized steel pipe 2 (°), determined by on-site measurement;

[0193] a, b, c, d, e, and f are empirical correction coefficients based on test data or on-site calibration;

[0194] Secondly, the single discharge volume V of the pouring funnel is set with the q value as the upper limit dose and the release interval t, satisfying:

[0195]

[0196] Finally, the η parameter is corrected:

[0197]

[0198] Where η0 is the initial viscosity of the second-stage corbel concrete 3 under standard conditions; T is the ambient temperature; α is the viscosity-temperature sensitivity coefficient; and T0 is the test reference temperature.

[0199] Furthermore, in order to ensure that the concrete is fully compacted and formed after diversion and pouring in the slope area, and to avoid quality defects such as honeycombs, voids, and slag inclusions caused by local vibration leakage, vibration dead corners, or insufficient vibration energy, a directional intubation vibration power density model was proposed based on the traditional empirical fixed-point vibration process. It is used to quantitatively evaluate the matching relationship between vibration energy input and coverage range, optimize the vibration layout and rhythm, and improve the compaction uniformity.

[0200] During the insertion and vibration operation in a small-diameter galvanized steel pipe 2, the vibrator can only move up and down in a linear direction within the pipe, limiting the effective radius of the vibration energy. This can easily lead to "blind spots" and "weak vibration zones" in a complex warehouse where multiple steel pipes are staggered. Therefore, based on the principles of energy conservation and vibration propagation, the present invention establishes the following expression for vibration work density:

[0201]

[0202] Where: W is the vibration input work density per unit volume of the second-stage corbel concrete 3; α is the vibration energy conversion coefficient, which is 0.6-0.8; f is the vibrator frequency; A is the projected area of ​​the vibrating rod end; t is the single-point vibration time; V c is the volume of concrete within the vibration influence range;

[0203] V c Calculated by vibration radius:

[0204]

[0205] Where R is the effective radius of the vibrator in the second-stage corbel concrete 3, and the empirical model is:

[0206] R=β·d

[0207] Where, d is the diameter of the vibrating rod; β is the empirical coefficient, which is 3-5;

[0208] By substituting the above expression, the vibration energy density generated by each insertion vibration point is calculated, and the minimum target density threshold W is set. min , to ensure that all locations meet the compaction requirements:

[0209] W≥W min

[0210] The coverage blind area discrimination factor Δ is introduced and defined as follows:

[0211] Δ=S 未覆盖 / S 总投影

[0212] Where: S 未覆盖 is the total projected area not covered by the effective vibration radius; S 总投影The projected area of ​​the second phase corbel concrete 3 pouring area on the horizontal plane;

[0213] When Δ≤3%, the vibration coverage is sufficient; when Δ>5%, rearrange the spacing between the galvanized steel pipes or increase the vibration frequency; the spacing between the galvanized steel pipes should be controlled to be no less than 0.8m. Combined with the vibration radius model and the "staggered alternating" vibration strategy, while ensuring no repeated vibration, more than 90% of the area can be covered in a single pass, effectively improving construction efficiency and structural density;

[0214] After step five, there is step six, shear stress analysis and structural stability verification: the stress mode of the inclined concrete is calculated and analyzed, and compared with the shear strength of the contact surface, and the actual normal stress per unit area of ​​the first-stage bracket slope is σ n and the shear stress τ is:

[0215]

[0216] Where, P is the total weight of the gate between the first-stage corbel and the gate pier, A is the casting area of ​​the inclined surface acting on the first-stage corbel, θ is the inclination angle of the inclined surface, when the inclination angle is 45°, σ n =τ, constituting a typical shear-compression coupled stress state;

[0217] Verify whether the shear stress is within the safe range and compare it with the shear strength of the first-stage bracket slope; the first-stage bracket slope shear strength calculated by the friction shear stress model is τ 界面 , the safety factor of the first-stage corbel slope is obtained as:

[0218]

[0219] The safety factor is higher than the value recommended by the specification, and the shear stress is within the safe range.

[0220] It should be noted that the parts in this embodiment that are the same or similar to those in the third embodiment can be referenced to each other and will not be described in detail in this application.

[0221] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

Claims

1. A method for pouring slope concrete with pre-embedded diversion and shear-compression coupled stable control, characterized in that: The following steps are involved: Step 1: Pre-embed the galvanized steel pipe in the first-phase corbel: After fixing the first-phase corbel to the gate pier, fix the two galvanized steel pipes in the first-phase corbel steel mesh through the fixed steel bars. The lower end of the galvanized steel pipe fits the inclined template of the first-phase corbel, and the upper end of the galvanized steel pipe extends out of the top of the first-phase corbel; Step 2: First-stage corbel concrete pouring: pour the first-stage corbel concrete layer by layer in the first-stage corbel template. When pouring the first-stage corbel concrete of the upper layer, insert a vibrating rod into the first-stage corbel concrete of the lower layer and vibrate it. Step 3: Roughening the contact surface between the first-stage corbel concrete and the second-stage corbel concrete: Roughen the first-stage corbel bevel template. After the chiseling is completed, remove the scum and dust and rinse the chiseled surface. Step 4: Install the second-phase corbel concrete formwork: Fix the second-phase corbel concrete formwork and the first-phase corbel concrete through dowel bars and tension screws; Step 5. Second-phase corbel concrete pouring and vibration process: The second-phase corbel concrete flows into the pouring funnel through the discharge funnel, and then is poured into the second-phase corbel concrete template through the pouring funnel. Two galvanized steel pipes are used alternately for the second-phase corbel concrete pouring and vibration.

2. The method for pouring inclined concrete with pre-embedded diversion and shear-compression coupled stable control according to claim 1 is characterized in that: In step one, a groove is provided on the side wall of the first-phase corbel template, and the lower end of the galvanized steel pipe is beveled, and the bevel angle is consistent with the inclination angle of the side wall of the first-phase corbel template groove; the upper and lower ends of the galvanized steel pipe are wrapped with alkali-resistant geotextile and tied with galvanized iron wire; the top of the first-phase corbel template is provided with a buried position for the support hinge plate anchor bolt; before the galvanized steel pipe is buried, the center point position of the support hinge plate anchor bolt is measured to leave a distance between the galvanized steel pipe and the support hinge plate anchor bolt; the fixed steel bars include U-shaped clamps and inverted V-shaped supporting structure steel bars; the steel mesh of the side wall of the first-phase corbel inclined template in the first-phase corbel groove is welded with a U-shaped clamp, and the two ends of the U-shaped clamp are welded to the steel mesh of the side wall of the first-phase corbel groove, and the lower end of the galvanized steel pipe is fixed in the U-shaped clamp; the upper end of the galvanized steel pipe is obliquely supported by two steel bars, the upper end of the steel bar is welded to the outer wall of the galvanized steel pipe, and the lower end of the steel bar is fixed on the steel mesh at the top of the first-phase corbel, and the two steel bars form an inverted V-shaped supporting structure.

3. The method for pouring inclined concrete with pre-buried diversion and shear-compression coupled stable control according to claim 2, characterized in that: In step 1, a composite stability control model combining buoyancy, frictional resistance, and the structure's own gravity is established, and the stability control coefficient λ is used for evaluation. The stability control coefficient expression for the galvanized steel pipe's anti-floating and anti-slip properties is: Where, k is the construction coefficient; A f is the bearing area of ​​the U-shaped clamp and the inverted V-shaped support structure steel bar; σ y is the yield strength of the inverted V-shaped support structure steel bars and U-shaped clamp steel bars; γ c is the concrete density; r is the inner radius of the galvanized steel pipe; h is the effective height of the galvanized steel pipe buried in the first-stage corbel concrete; μ is the friction coefficient between the galvanized steel pipe and the first-stage corbel concrete; d is the outer diameter of the galvanized steel pipe; ρ s is the material density of the galvanized steel pipe; r0, r i are the outer radius and inner radius of the galvanized steel pipe respectively; g is the acceleration due to gravity; According to the value of λ, U-shaped clamps and inverted V-shaped supporting structural steel bars are used to clamp the galvanized steel pipe in the first-stage bracket.

4. The method for pouring inclined concrete with pre-buried diversion and shear-compression coupled stable control according to claim 1, characterized in that: In step 3, several equidistant dovetail-shaped shallow grooves are set on the roughened surface; a friction shear stress model is established, and the functional relationship between the shear strength and the stress of the roughened surface is: τ=c+σ n ·tanφ Where, τ is the shear strength of the roughened surface; c is the adhesion of the roughened surface; σ n is the normal stress of the roughened surface; φ is the friction angle of the roughened surface.

5. The method for pouring slope concrete with pre-embedded diversion and shear-compression coupled stable control according to claim 1, characterized in that: In step 4, adhesive strips are attached between the second-phase corbel concrete formwork and the first-phase corbel concrete and the gate pier concrete; one end of the dowel bar is inserted into the first-phase corbel concrete, and the other end is extended out of the first-phase corbel concrete and welded to a U-shaped fixing ring. The opposite surfaces of the second-phase corbel concrete formwork are connected by tension screws, which are fixed by the tension screws and the U-shaped fixing ring; stop strips are set at the joints of the second-phase corbel concrete formwork to seal, and the tension screws are tightened until there is no leakage; the lateral horizontal load exerted on the inner wall of the second-phase corbel concrete formwork by the second-phase corbel concrete in the free-falling state from the galvanized steel pipe is checked, and the expression is: Where σ h is the horizontal lateral pressure of the second-phase corbel concrete formwork; γ c is the weight of the second-stage corbel concrete; R is the radius of the lower end of the galvanized steel pipe; μ is the interface friction coefficient between the second-stage corbel concrete and the second-stage corbel concrete formwork; K is the lateral pressure diffusion coefficient.

6. The method for pouring inclined concrete with pre-embedded diversion and shear-compression coupled stable control according to claim 1, characterized in that: In step five, the discharge funnel is connected to the pouring funnel through U-shaped steel bars. A funnel switch is provided at the bottom of the pouring funnel, and a height difference is provided between the bottom of the funnel switch and the top of the galvanized steel pipe. The amount of material discharged each time is controlled by the funnel switch. After the second-phase corbel concrete flows to the middle of the galvanized steel pipe, the material feeding is stopped and the pouring funnel is turned to the top of another galvanized steel pipe. At the same time, an inserted vibrating rod is inserted into the galvanized steel pipe for vibration. The two galvanized steel pipes are alternately filled and vibrated.

7. The method for pouring inclined concrete with pre-embedded diversion and shear-compression coupled stable control according to claim 6, characterized in that: In step 5, the second-phase corbel concrete is poured into the second-phase corbel concrete module at a low pressure and a closed-loop model for on-site pouring control is established. First, the relationship between the viscous resistance and the driving pressure difference during the flow of the second-phase corbel concrete in the galvanized steel pipe is analyzed, and the safe feed rate function per unit time q is established, which is expressed as: Where, q is the volume of material passing through the galvanized steel pipe per unit time; r is the inner radius of the galvanized steel pipe; ΔP is the static pressure difference of the pouring funnel; η is the dynamic viscosity of the second-stage corbel concrete; L is the effective length of the galvanized steel pipe; ψ is the comprehensive resistance coefficient; Secondly, the single discharge volume V of the pouring funnel is set with the q value as the upper limit dose and the release interval t, satisfying: Finally, the η parameter is corrected: Where η0 is the initial viscosity of the second-stage corbel concrete under standard conditions; T is the ambient temperature; α is the viscosity temperature sensitivity coefficient; T0 is the test reference temperature.

8. The method for pouring inclined concrete with pre-embedded diversion and shear-compression coupled stable control according to claim 1, characterized in that: In step five, a directional intubation vibration work density model is proposed, and the vibration work density expression is established: Where: W is the vibration input work density per unit volume of the second-stage corbel concrete; α is the vibration energy conversion coefficient; f is the vibrator frequency; A is the projected area of ​​the vibrating rod end; t is the single-point vibration time; V c is the volume of concrete within the vibration influence range; V c Calculated by vibration radius: Where R is the effective action radius of the vibrator in the second-stage corbel concrete, and the empirical model is: R=β·d Where, d is the diameter of the vibrating rod; β is the empirical coefficient; The spacing between galvanized steel pipes is obtained based on the directional pipe insertion vibration work density model.

9. The method for pouring inclined concrete with pre-embedded diversion and shear-compression coupled stable control according to claim 4, characterized in that: After step five, there is step six, shear stress analysis and structural stability verification: calculate and analyze the stress mode of the inclined concrete, and compare and verify it with the shear strength of the contact surface. The actual normal stress per unit area of ​​the first-stage bracket slope σ n and the shear stress τ is: Where P is the total weight of the gate between the first-stage corbel and the gate pier, A is the casting area of ​​the inclined surface acting on the first-stage corbel, θ is the inclination angle of the inclined surface, σ n =τ, constituting a typical shear-compression coupled stress state; Verify whether the shear stress is within the safe range and compare it with the shear strength of the first-stage bracket slope; the first-stage bracket slope shear strength calculated by the friction shear stress model is τ 界面 , the safety factor of the first-stage corbel slope is obtained as: The safety factor is higher than the value recommended by the specification, and the shear stress is within the safe range.

10. A slope concrete, characterized in that: Obtained by the method according to any one of claims 1 to 9.

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