Method for reinforcing column through hoop die casting

Abstract

The invention relates to the technical field of building structure reinforcement, and provides a hoop die casting column reinforcing method which comprises the following steps: step 1, pretreating a to-be-reinforced concrete column; 2, casting coating paste is prepared, and then the outer surface of the concrete column is coated with the casting coating paste; 3, a silicon carbide ceramic plate serves as a mold box, a 25mm square steel reinforcing frame is arranged on the back of the silicon carbide ceramic plate, then the mold plate is tightened and fixed to the periphery of the concrete column through angle locking buckles, the distance between the ceramic plate and the concrete face is adjusted, a uniform gap is kept, and it is guaranteed that the thickness of an alloy layer is consistent; fourthly, alloy is poured into the mold box; and fifthly, after the alloy layer is completely cured, the formwork is removed, whether the surface thickness of the reinforcing layer meets the requirement of 25-30 mm or not is checked, and then a fireproof coating is brushed to meet the building specification requirement. Through combined innovation of a hoop die casting technology, a special alloy material and an interface optimization process, the problems that a traditional reinforcing method is low in bearing capacity, large in occupied space, unreliable in bonding and the like are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building structure reinforcement, in particular to a hoop mold casting reinforced column method. BACKGROUND

[0002] In the field of building structure reinforcement, the reinforcement of concrete columns is a common requirement. The current mainstream technology is to use steel plate welding or bonded steel reinforcement method (i.e. by welding steel plates or using adhesives to fix steel plates on the outer periphery of the concrete column). This method is widely used in the industry because it can strengthen the column structure to some extent and meet the basic load-bearing requirements;

[0003] The typical layout of the traditional reinforcement scheme is that the steel plate is directly fixed on the surface of the concrete column to form a reinforcement layer through welding or bonding. This technology refers to industry standards (such as the Chinese national standard GB50367) and actual engineering data, which proves its feasibility and popularity.

[0004] However, the existing reinforcement method has the following shortcomings:

[0005] First, the load-bearing capacity improvement rate of the existing technology is usually not more than 40%. This is due to the structural limitations of the reinforcement layer, such as air bubble defects that can cause poor adhesion between the reinforcement layer and the concrete, thereby reducing the overall strength. Under extreme loads such as earthquakes or extreme wind loads, this method is prone to failure and cannot provide sufficient redundancy protection;

[0006] Second, traditional reinforcement requires welding steel plates on the outer periphery of the concrete column, which occupies a large amount of space (especially in areas with limited headroom, such as the core tube of a high-rise building). For example, the construction process involves complex operations such as precision welding, which can easily introduce human errors and increase the construction period and cost. In addition, this method is difficult to adapt to irregular columns and has poor flexibility;

[0007] Third, in special scenarios such as areas with extreme loads or space-limited high-rise building core tubes, the existing technology cannot meet the requirements. Actual data shows that in cases where the headroom is insufficient, the installation of steel plates can cause space conflicts, and the reinforcement effect is further weakened due to air bubble defects. This limits its application in large-span or high-density buildings.

[0008] In view of this, the present application proposes a hoop mold casting reinforced column method. SUMMARY

[0009] The present application proposes a hoop mold casting reinforced column method, which solves the problem of insufficient load-bearing capacity in the prior art.

[0010] The technical solution of the present application is as follows:

[0011] In one aspect, a hoop mold includes a square steel set outside a concrete column, and a lock angle buckle is arranged at each corner of the square steel, and a silicon carbide ceramic plate is arranged around the inner side of the square steel.

[0012] In another aspect, a hoop mold casting reinforced column method is achieved by the above-mentioned hoop mold, including the following steps:

[0013] Step one: pretreat the concrete column to be reinforced, and the specific implementation process is as follows:

[0014] A1, polish the concrete column into a circular arc angle to eliminate stress concentration points;

[0015] A2, drill a through hole with a diameter of 30mm every 50cm vertically on the concrete column, and the hole depth penetrates the column;

[0016] A3, remove the stains and dust on the surface of the column, rinse with water and dry until no water residue is left, and ensure the surface is clean;

[0017] Step two: prepare the casting coating paste, and then apply the casting coating paste to the outer surface of the concrete column with a thickness of 2-3mm;

[0018] Step three: use the silicon carbide ceramic plate as a mold box, back up the 25mm square steel reinforcement frame, then use the lock angle buckle to tighten and fix the mold plate around the concrete column, and then adjust the distance between the ceramic plate and the concrete surface to maintain a uniform gap of 25-30mm, ensure the uniform thickness of the alloy layer, and check the position of the mold plate after the gap;

[0019] Step four: pour the alloy into the mold box, and the specific implementation process is as follows:

[0020] B1, melt the special alloy to remove surface impurities;

[0021] B2, slowly pour the pure alloy along the four sides into the mold box at the same time, and the pouring speed is controlled at 5-10cm / min, the single pouring height is 300mm, not more than 500mm, and the pouring thickness is about 25-30mm to prevent poor adhesion or internal bubbles due to excessive height;

[0022] B3, naturally cool and solidify after pouring, and the alloy cooling shrinkage generates a ring force, so that the internal concrete is in a three-way compression state;

[0023] Step five: after the alloy layer is completely solidified, remove the mold plate, check whether the thickness of the reinforced layer surface meets the requirement of 25-30mm, and then apply a fireproof coating to meet the requirements of building specifications.

[0024] Preferably, the preparation process of the defoaming agent coating is as follows:

[0025] C1, take the appropriate amount of paraffin block, placed in a heat-resistant container, heated to 80-100℃, avoid overheating carbonization, continuous stirring until completely melted into a transparent liquid, let the melted paraffin naturally cool to 40-50℃ for standby;

[0026] C2, take the same amount of casting paint defoamer as the melted paraffin;

[0027] C3, pour the cooled liquid paraffin into the defoamer according to 1:1, use a mechanical stirrer or a manual tool to stir until a uniform, viscous paste-like mixture is formed.

[0028] Preferably, the defoamer is an organic polyether ester, mineral oil, alcohol complex product.

[0029] Preferably, the stirring speed of the mechanical stirrer or manual tool is 100-200 rpm, and the stirring time is 5-10 minutes.

[0030] Preferably, the main material of the special alloy is composed of iron (Fe) as the main component, and the remaining elements include chromium (Gr) 3.5-4.5%, carbon (C) 1.05-1.20%, manganese (Mn) 0.25-0.30%, silicon (Si) 0.15-0.35%, sulfur (S) ≤0.025%, phosphorus (P) ≤0.025%, and copper (Cu) ≤0.25%.

[0031] Preferably, the specific melting process of the special alloy is as follows:

[0032] D1, preheat the melting furnace to 1200-1500℃ to ensure uniform heating;

[0033] D2, put the mixed raw materials of the special alloy into the furnace in batches, first add Fe, then add the remaining raw materials after it is semi-melted, keep the furnace temperature stable throughout to prevent oxidation, the melting time is 30-60 minutes, until the raw materials are completely liquefied to form a uniform molten pool;

[0034] D3, after melting, let the molten liquid stand for 2-5 minutes, let the impurities float to the surface, and remove the surface dross with refractory tools.

[0035] Preferably, after the special alloy is melted, if there are more impurities, 0.05-0.15% of high-purity aluminum powder can be added, and the specific adding process is as follows:

[0036] E1, preheat the aluminum powder in an oven at 80-100℃ for 10 minutes;

[0037] E2, sprinkle the aluminum powder on the surface of the molten liquid with a refractory steel spoon in 3-4 times, do not pour it all at once to avoid local violent reaction spatter;

[0038] E3. Stir the molten liquid at low speed with a graphite rod for 1-2 minutes to promote uniform diffusion of aluminum powder. After stirring, let it stand for 1 minute to allow Al2O3 to float fully.

[0039] The working principle and beneficial effects of this invention are as follows:

[0040] 1. The cooling and shrinkage of the alloy layer generates 0.1% to 0.3% circumferential stress, which puts the concrete in a triaxial compression state, greatly improving the compressive strength. Test data shows that the ultimate load after reinforcement reaches 1600kN, which is 60% higher than the original column (1000kN) without reinforcement, far exceeding the traditional steel plate reinforcement.

[0041] 2. The casting coating paste (containing a composite formula of paraffin wax and defoamer) effectively eliminates air bubbles, ensuring a gapless bond between the alloy and concrete. The pre-treated permeable round holes form a mechanical embedding, preventing the risk of peeling.

[0042] 3. The alloy layer is only 25-30mm thick, which is much less than the space required for traditional steel plate reinforcement. It is especially suitable for areas with limited clearance (such as high-rise core tubes). The silicon carbide ceramic template backs the square steel frame and the gap is quickly locked by the corner lock to ensure uniform thickness.

[0043] 4. The alloy composition uses high-carbon chromium steel, which can provide high hardness, wear resistance and shrinkage crack resistance. The alloy layer forms a permanent hoop constraint on the concrete, delaying crack development. Attached Figure Description

[0044] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0045] Figure 1 This is a schematic diagram of the structure of a ring clamp mold according to the present invention;

[0046] Figure 2 This is a flowchart of a method for reinforcing columns by ring-hoop casting according to the present invention.

[0047] In the diagram: 1. Concrete column; 2. Silicon carbide ceramic plate; 3. Square steel; 4. Corner lock; 5. Casting coating paste; 6. Rounded corner; 7. Round hole. Detailed Implementation

[0048] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0049] Example 1:

[0050] like Figure 1As shown, the embodiment proposes a hoop mold, including a square steel 3 sleeved outside the concrete column 1, and a lock angle buckle 4 arranged at each corner outside the square steel 3, and a silicon carbide ceramic plate 2 arranged around the inside of the square steel 3.

[0051] Embodiment two:

[0052] The embodiment proposes a hoop mold casting reinforced column method, which is realized by the hoop mold in embodiment one, including the following steps:

[0053] Step one: pretreat the concrete column 1 to be reinforced, and the specific implementation process is as follows:

[0054] A1, polish the concrete column 1 into a circular arc corner 6 to eliminate stress concentration points;

[0055] A2, drill a through circular hole 7 with a diameter of 30 mm every 50 cm vertically in the concrete column 1, and the hole depth penetrates the column;

[0056] A3, remove the stains and floating dust on the column surface, rinse with clean water and dry until no water residue is left, and ensure the surface is clean;

[0057] Step two: prepare the casting coating paste 5, and then apply the casting coating paste 5 on the outer surface of the concrete column 1 with a thickness of 2 mm;

[0058] Step three: use the silicon carbide ceramic plate 2 as a mold box, back up a 25 mm square steel reinforcement frame, then tighten and fix the mold plate around the concrete column 1 with the lock angle buckle 4, and keep the distance between the ceramic plate and the concrete surface at 25 mm to ensure the uniform gap and the uniform thickness of the alloy layer, and check the gap and lock the position of the mold plate;

[0059] Step four: pour the alloy into the mold box, and the specific implementation process is as follows:

[0060] B1, melt the special alloy to remove the surface impurities;

[0061] B2, slowly pour the pure alloy along the four sides into the mold box at the same time, and control the pouring speed at 5 cm / min, the single pouring height is 300 mm, not more than 500 mm, and the pouring thickness is about 25 mm to prevent poor adhesion or internal bubbles due to too high pouring;

[0062] B3, naturally cool and solidify after pouring, and the alloy cooling shrinkage generates 0.1% to 0.3% ring force, so that the internal concrete is in a three-way compression state, thereby further improving the vertical bearing capacity of the reinforced column;

[0063] Step five: remove the mold plate after the alloy layer is completely solidified, check whether the thickness of the reinforced layer surface meets the requirement of 25-30 mm, and then brush a fireproof coating to meet the requirements of the building specification.

[0064] Further, in step two, the preparation process of the defoaming agent coating 5 is as follows:

[0065] C1, take the appropriate amount of paraffin block, placed in a heat-resistant container, heated to 80℃, avoid overheating carbonization, continuous stirring until completely melted into a transparent liquid, the melting process needs to be carried out in a ventilated environment to prevent harmful gases, let the melted paraffin cool to 40℃ naturally (keep liquid but not too hot) for standby;

[0066] C2, measure the same amount of casting coating defoaming agent as the melted paraffin;

[0067] C3, pour the cooled liquid paraffin into the defoaming agent according to the ratio of 1:1, use a mechanical stirrer or manual tool for stirring, the stirring speed is 100rpm, the stirring time is 5 minutes, until a uniform, viscous paste-like mixture is formed.

[0068] Further, the defoaming agent is an organic polyether ester, mineral oil, alcohol composite product, and the specific model is TEGOFoamex 810 of Yingchuang.

[0069] Further, in step four, the main material of the special alloy is composed of iron (Fe) as the main component, and the remaining elements include chromium (Gr) 3.5%, carbon (C) 1.05%, manganese (Mn) 0.25%, silicon (Si) 0.15%, sulfur (S) 0.025%, phosphorus (P) 0.025%, and copper (Cu) 0.25%.

[0070] Further, in step four, the specific melting process of the special alloy is as follows:

[0071] D1, preheat the melting furnace to 1200℃ to ensure uniform heating;

[0072] D2, put the mixed raw materials of the special alloy into the furnace in batches, first add Fe, then add the remaining raw materials after it is half melted, keep the furnace temperature stable throughout to prevent oxidation, the melting time is 30 minutes, until the raw materials are completely liquefied to form a uniform molten pool;

[0073] D3, after melting, let the molten liquid stand for 2 minutes, let the impurities (such as sulfur, phosphorus oxides) float to the surface, and remove the surface dross with refractory tools (such as slag rake).

[0074] Further, after the special alloy is melted, if there are more impurities, 0.05% of high-purity aluminum powder can be added, and the specific adding process is as follows:

[0075] E1, preheat the aluminum powder in an 80℃ oven for 10 minutes;

[0076] E2, sprinkle the aluminum powder onto the surface of the molten liquid in 4 times with a refractory steel spoon, do not pour it all at once to avoid local violent reaction spatter;

[0077] E3, use graphite rod to stir the melt at low speed (≤30 rpm) for 1 minute to promote uniform dispersion of aluminum powder, and stand for 1 minute after stirring to allow Al2O3 to float up fully.

[0078] Example Three:

[0079] This embodiment proposes a hoop mold casting reinforced column method, which differs from example two in that it includes the following steps:

[0080] Step one: pretreat the concrete column 1 to be reinforced, and the specific implementation process is as follows:

[0081] A1, polish the concrete column 1 into a circular arc angle 6 to eliminate stress concentration points;

[0082] A2, drill a through circular hole 7 with a diameter of 30 mm every 50 cm vertically in the concrete column 1, and the hole depth penetrates the column;

[0083] A3, remove surface stains and floating dust, rinse with clean water and dry until no water residue is left to ensure surface cleanliness;

[0084] Step two: prepare the casting coating paste 5, then apply the casting coating paste 5 to the outer surface of the concrete column 1 with a thickness of 2-3 mm;

[0085] Step three: use silicon carbide ceramic plate 2 as a mold box, back up a 25 mm square steel reinforcement frame, then use angle lock buckle 4 to tighten and fix the mold plate around the concrete column 1, and adjust the distance between the ceramic plate and the concrete surface to maintain a uniform gap of 28 mm to ensure consistent alloy layer thickness. Check the gap and lock the position of the mold plate;

[0086] Step four: pour the alloy into the mold box, and the specific implementation process is as follows:

[0087] B1, melt the special alloy to remove surface impurities;

[0088] B2, slowly pour the pure alloy along the four sides into the mold box at the same time, with a pouring speed controlled at 8 cm / min, a single pouring height of 300 mm, not exceeding 500 mm, and a pouring thickness of about 28 mm to prevent poor adhesion or internal bubbles due to excessive height;

[0089] B3, naturally cool and solidify after pouring, and the alloy cooling shrinkage generates 0.1% to 0.3% ring force, making the internal concrete in a three-way compression state;

[0090] Step five: remove the mold after the alloy layer is completely solidified, check if the thickness of the reinforcement layer meets the requirement of 28 mm, then apply a fireproof coating to meet the building specification requirements.

[0091] Embodiment Four

[0092] The embodiment proposes a hoop mold casting reinforced column method, which is different from the embodiment two and comprises the following steps.

[0093] Step one: pretreat the concrete column 1 to be reinforced, and the specific implementation process is as follows:

[0094] A1, polish the concrete column 1 into a circular arc angle 6 to eliminate stress concentration points;

[0095] A2, drill a through circular hole 7 with a diameter of 30mm every 50cm vertically in the concrete column 1, and the hole depth penetrates the column body;

[0096] A3, remove the stains and floating dust on the column surface, rinse with clean water and dry until no water residue is left to ensure the surface is clean;

[0097] Step two: prepare the casting coating paste 5, and then apply the casting coating paste 5 on the outer surface of the concrete column 1 with a thickness of 2-3mm;

[0098] Step three: use the silicon carbide ceramic plate 2 as a mold box, back up the 25mm square steel reinforcement frame, then use the angle lock buckle 4 to tighten and fix the mold plate around the concrete column 1, and adjust the distance between the ceramic plate and the concrete surface to maintain a uniform gap of 30mm to ensure the uniform thickness of the alloy layer. After checking the gap, lock the position of the mold plate;

[0099] Step four: pour the alloy into the mold box, and the specific implementation process is as follows:

[0100] B1, melt the special alloy to remove surface impurities;

[0101] B2, slowly pour the pure alloy along the four sides into the mold box at the same time, and control the pouring speed at 10cm / min, the single pouring height is 300mm, not more than 500mm, and the pouring thickness is about 30mm to prevent poor adhesion or internal bubbles due to too high pouring;

[0102] B3, naturally cool and solidify after pouring, and the alloy cooling shrinkage generates 0.1%~0.3% annular force, so that the internal concrete is in a three-way compression state;

[0103] Step five: after the alloy layer is completely solidified, remove the mold plate, check whether the thickness of the reinforcement layer surface meets the requirement of 30mm, and then apply a fireproof coating to meet the building specification requirements.

[0104] Test Example

[0105] The test example is used to detect the single column bearing capacity, and the specific experimental steps are as follows:

[0106] (1) Take a standard concrete square column of 300mm×300mm×1500mm, and cast a molded alloy layer on the outside of the square column according to the method of Example 1, as the experimental group (ring-hoop molded reinforced column).

[0107] (2) Set up control groups: control group A (original column without reinforcement) and control group B (conventional steel-bonded reinforced column);

[0108] (3) Place the three sets of specimens vertically on the press platform and level them with a spirit level;

[0109] (4) Apply an initial load (10% of the estimated ultimate load), hold the load for 5 minutes to eliminate the gap, and check the zeroing status of the strain gauges and displacement gauges.

[0110] (5) Graded loading levels, namely 0%~30%Fu (two minutes), 30%~80%Fu (three minutes), 80%~destruction;

[0111] (6) Check whether the gold layer in the experimental combination delays concrete cracking due to shrinkage constraint, the bond state between the alloy layer and concrete at failure, and collect the peak reading of the press and the axial compression value at the corresponding Fu. Δ L), load-bearing capacity improvement rate, specific experimental data are shown in the table below:

[0112]

[0113] As can be seen in the upper right corner, the bearing capacity of the ring-studded reinforced column has been increased by 60%, which is a significant technological advancement compared to existing technologies.

[0114] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A ring clamp mold, characterized in that, It includes a square steel (3) sleeved on the outside of the concrete column (1), with corner locks (4) provided at the four corners of the outside of the square steel (3), and silicon carbide ceramic plates (2) provided on the four sides of the inside of the square steel (3).

2. A method for reinforcing columns by ring-hoop die casting, implemented using the ring-hoop mold as described in claim 1, characterized in that, Includes the following steps: Step 1: Pre-treatment of the concrete column (1) to be reinforced. The specific implementation process is as follows: A1. Grind the concrete column (1) into a rounded corner (6) to eliminate stress concentration points; A2. A water drill is used to drill through round holes (7) with a diameter of 30 mm every 50 cm vertically in the concrete column (1), with the hole depth penetrating the column. A3. Remove stains and dust from the column surface, rinse with clean water and let it air dry until no moisture remains to ensure the surface is clean; Step 2: Prepare casting coating paste (5), and then apply casting coating paste (5) to the outer surface of concrete column (1) with a thickness of 2-3 mm; Step 3: Use silicon carbide ceramic plate (2) as a mold box, backed with 25mm square steel reinforcement frame, and then use corner buckles (4) to tighten and fix the template around the concrete column (1). Adjust the distance between the ceramic plate and the concrete surface to maintain a uniform gap of 25-30mm to ensure that the alloy layer thickness is consistent. After checking the gap, lock the template position. Step 4: Cast the alloy into the mold box. The specific implementation process is as follows: B1. Melt special alloys to remove surface impurities; B2. Pour the pure alloy slowly into the mold box along the circumference at the same time. The casting speed should be controlled at 5-10cm / min. The single casting height should be 300mm and not exceed 500mm. The casting thickness should be about 25-30mm to prevent poor bonding or air bubbles inside after the casting is too high. B3. After casting, the alloy cools and solidifies naturally. The cooling and shrinkage of the alloy generates a ring force, which puts the internal concrete in a triaxial compression state. Step 5: After the alloy layer has fully cured, remove the formwork, check whether the surface thickness of the reinforcement layer meets the requirement of 25-30mm, and then apply a fireproof coating to meet the building code requirements.

3. The method for reinforcing columns by ring-hoop casting according to claim 2, characterized in that, In step two, the specific process for preparing the defoamer coating (5) is as follows: C1. Take an appropriate amount of paraffin wax block, place it in a heat-resistant container, heat it to 80-100℃, avoid overheating and carbonization, and continue stirring until it is completely melted into a transparent liquid. Let the melted paraffin wax cool naturally to 40-50℃ for later use. C2. Measure an equal amount of casting coating defoamer as molten paraffin wax; C3. Pour the cooled liquid paraffin into the defoamer and mix at a 1:1 ratio. Use a mechanical stirrer or hand tool to stir until a uniform, viscous paste-like mixture is formed.

4. The method for reinforcing columns by ring-hoop casting according to claim 3, characterized in that, The defoamer is a compound product of organic polyether ester, mineral oil, and alcohol.

5. The method for reinforcing columns by ring-hoop casting according to claim 3, characterized in that, The mechanical stirrer or manual tool is used at a speed of 100-200 rpm for 5-10 minutes.

6. The method for reinforcing columns by ring-hoop casting according to claim 1, characterized in that, In step four, the main material composition of the special alloy is iron (Fe), with the following content of other elements: chromium (Gr) 3.5-4.5%, carbon (C) 1.05-1.20%, manganese (Mn) 0.25-0.30%, silicon (Si) 0.15-0.35%, sulfur (S) ≤0.025%, phosphorus (P) ≤0.025%, and copper (Cu) ≤0.25%.

7. The method for reinforcing columns by ring-hoop casting according to claim 6, characterized in that, In step four, the specific smelting process of the special alloy is as follows: D1. Preheat the smelting furnace to 1200-1500℃ to ensure uniform heating; D2. Add the mixed raw materials of special alloy into the furnace in batches. First add Fe, and after it is half melted, add the remaining raw materials. Keep the furnace temperature stable throughout the process to prevent oxidation. The melting time is 30-60 minutes until the raw materials are completely liquefied and a uniform molten pool is formed. D3. After melting, let the molten liquid stand for 2-5 minutes to allow impurities to float to the surface, and remove the surface slag with refractory tools.

8. The method for reinforcing columns by ring-hoop casting according to claim 7, characterized in that, If there are many impurities after the special alloy is melted, 0.05-0.15% high-purity aluminum powder can be added. The specific addition process is as follows: E1. Preheat aluminum powder in an oven at 80-100℃ for 10 minutes; E2. Use a refractory steel spoon to sprinkle the molten liquid onto the surface in 3-4 batches. Do not pour it all at once to avoid localized violent reactions and splashing. E3. Stir the molten liquid at low speed with a graphite rod for 1-2 minutes to promote uniform diffusion of aluminum powder. After stirring, let it stand for 1 minute to allow Al2O3 to float fully.

Images