Concrete road repairing method

Abstract

The invention discloses a concrete road repairing method, a repairing material is used for repairing a concrete road, the raw material of the repairing material contains an additive, and the concrete road repairing method comprises the following steps: verifying the mixing amount of the additive in the raw material of the repairing material, uniformly mixing the raw materials in proportion according to a verification result to obtain a premixed material; and transporting the premixed material to a construction site, pouring the premixed material to a required construction position, and carrying out surface finishing, maintenance and scrapping of part of the premixed material. According to the concrete road repairing method disclosed by the invention, the mixing amount of the additive in the raw materials of the repairing material is verified, and the mixing amount of the additive is adaptively adjusted according to the change of air temperature, so that the repairing material for repairing the road has long-time slump retaining performance, concrete does not need to be mixed on site, and the repairing material can be quickly coagulated after being poured; therefore, the construction period is effectively shortened, the production cost is saved, and the repaired concrete road has better strength.

Description

Technical Field

[0001] The invention belongs to the technical field of road repair, and in particular relates to a concrete road repair method. Background Art

[0002] In the prior art, when repairing roads, ordinary cement concrete is poured on the damaged road surface or the expansion joints between roads. This traditional repair method takes a long time to construct and solidify, and requires a long waiting time for closing roads, bridges, and businesses, which seriously affects the operation of cities and economic development. In addition, concrete materials are mixed on site, which causes great pollution to the site, and raw materials need to be piled on site. At the same time, the dust and noise generated during the on-site mixing process will also affect the surrounding residents. Summary of the invention

[0003] In view of this, in order to overcome the defects of the prior art, an object of the present invention is to provide an improved concrete road repairing method.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A concrete road repair method, using a repair material to repair the concrete road, the raw material of the repair material contains an admixture, and the concrete road repair method comprises the following steps:

[0006] Verify the dosage of the admixture in the raw materials of the repair material, and mix the raw materials in proportion to obtain a premix according to the verification result; transport the premix to the construction site and pour it to the required construction position, and then perform finishing, maintenance and scrapping of part of the premix.

[0007] According to some preferred implementation aspects of the present invention, the admixture includes a sulphoaluminate retarder and a first component, and the first component includes a water reducer. In some embodiments of the present invention, the first component also includes a common retarder tartaric acid, and the admixture includes 2 to 6 parts of water reducer, 3 to 10 parts of sulphoaluminate retarder, and 0 to 1.5 parts of tartaric acid in parts by weight.

[0008] According to some preferred implementation aspects of the present invention, the method for verifying the dosage of the admixture in the raw material of the repair material is: verifying the dosage of the sulphoaluminate retarder in the admixture and the dosage of the water reducer in the first component.

[0009] Preferably, in some embodiments of the present invention, the initial slump of the concrete is greater than or equal to 180 mm, and the slump decreases by no more than 30 mm within three hours. In addition, if the slump is insufficient during the preparation of the concrete, the water content in the raw materials is ensured to be no more than 10 kg / m 3 Under the premise of this, the slump can be adjusted by adding water reducing agent.

[0010] According to some preferred embodiments of the present invention, the method for verifying the dosage of the sulphoaluminate retarder in the admixture is: determining a reference temperature, when the ambient temperature during concrete road repair is compared with the reference temperature, the change rate of the dosage of the sulphoaluminate retarder is 10% to 30% for every 15°C change in the ambient temperature.

[0011] According to some preferred implementation aspects of the present invention, when the ambient temperature during concrete road repair is compared with the reference temperature, the dosage of the sulphoaluminate retarder is reduced by 10% to 30% for every 15°C decrease, preferably, the dosage of the sulphoaluminate retarder is reduced by 15% to 25% for every 15°C decrease; the dosage of the sulphoaluminate retarder is increased by 10% to 30% for every 15°C increase, preferably, the dosage of the sulphoaluminate retarder is increased by 15% to 25% for every 15°C increase. Specifically, too low a content of sulphoaluminate retarder will result in insufficient collapse retention time and premature solidification of concrete; too much content of sulphoaluminate retarder will result in insufficient concrete strength. However, changes in air temperature will lead to different requirements for sulphoaluminate retarder in the raw materials of the repair material. When the temperature is low, the required sulphoaluminate retarder will be less than the sulphoaluminate retarder required in a high temperature environment. Adjusting the content of sulphoaluminate retarder according to the change in temperature can save production costs while ensuring the strength of concrete.

[0012] According to some preferred implementation aspects of the present invention, when at the reference temperature, the admixture includes 3 to 10 parts of sulphoaluminate retarder.

[0013] According to some preferred implementation aspects of the present invention, the reference temperature is room temperature, and the room temperature is 20-30°C, preferably 20-25°C.

[0014] According to some preferred implementation aspects of the present invention, the raw materials of the repair material further include composite cementitious material, aggregate, characteristic components and water, and the method of uniformly mixing the raw materials in proportion to obtain the premix is:

[0015] The composite cementitious material and aggregate in the raw materials of the verified repair material are mixed evenly in proportion to obtain a premix; then the characteristic components, admixtures and water in the raw materials of the repair material are added into the premix in proportion and mixed evenly to obtain the premix.

[0016] Preferably, in some embodiments of the present invention, the raw materials of the repair material include, by weight, 320-770 parts of composite cementitious material, 1500-1800 parts of aggregate, 0-5 parts of characteristic component, 8-12 parts of admixture, and 130-180 parts of water.

[0017] Preferably, the aggregate includes coarse aggregate and fine aggregate, the particle size of the fine aggregate is medium sand with a fineness modulus of 2.5 to 2.9 and a particle size of 5 to 15 mm or a continuously graded crushed stone with a particle size of 5 to 25 mm according to the engineering requirements; the mass ratio of fine aggregate to coarse aggregate is 30 to 50:30 to 55. In parts by weight, the composite cementitious material includes 200 to 400 parts of silicate cement, 100 to 250 parts of sulphoaluminate cement, 10 to 40 parts of gypsum and 10 to 80 parts of admixture; in parts by weight, the characteristic components include 0 to 2 parts of flow regulator, 0 to 1 part of water retaining agent and 0 to 1.5 parts of early strength agent. Among them, silicate cement is silicate cement with a 28-day standard mortar compressive strength greater than 52.5 MPa; the strength grade of sulphoaluminate cement can be SAC52.5; gypsum is one or a combination of anhydrous hard gypsum and semi-hydrated gypsum; and the admixture is one or a combination of fly ash, mineral powder, and microspheres.

[0018] According to some preferred implementation aspects of the present invention, the finishing includes primary finishing and secondary finishing, and the secondary finishing needs to be completed before the initial setting of the concrete and within 4 hours after the pouring is completed.

[0019] According to some preferred embodiments of the present invention, the method for scrapping part of the premix is: after obtaining the premix, for the part of the premix that has not been used for more than 3 hours, it is scrapped by adding water and the sulphoaluminate retarder to this part of the premix.

[0020] Preferably, the concrete road repair method of the present invention comprises the following steps:

[0021] Step 1: Verify the dosage of admixtures in the raw materials of the repair material.

[0022] Step 2: According to the verification result in step 1, the composite cementitious material and aggregate in the raw materials of the verified repair material are put into a concrete mixer in proportion and stirred for 30 to 60 seconds to obtain a premix (dry material).

[0023] Step 3: Add the characteristic components, admixtures and water in the raw materials of the repair material into a concrete mixer in proportion and stir for 240 to 360 seconds until the system reaches a colloidal state to obtain a premix.

[0024] Step 4: Place the premix in a tank truck, transport it to the construction site and pour it to the required construction position. Use a vibrating rod to vibrate it to increase the working performance of the concrete, and then perform a finishing operation. No watering or curing can be performed after the first finishing operation. In addition, during the transportation of the premix, the tank body of the tank truck needs to rotate slowly and continuously. The first finishing operation needs to be performed within 3 hours after the pouring is completed.

[0025] Step 5: Complete the secondary finishing before the concrete begins to set and within 4 hours after pouring to ensure a smooth concrete surface.

[0026] Step 6: After the final setting of the concrete, watering and film covering are carried out for maintenance; after the final setting, the surface of the concrete turns white and has initial hardness.

[0027] Step 7: For the part of premix that has not been used for more than 3 hours, add water and sulphoaluminate retarder to this part of premix to scrap it. Do not leave it in the concrete tanker or other means of transportation.

[0028] In some embodiments of the present invention, for projects that require secondary pouring, if the second pouring time cannot be guaranteed to be completed within 3 hours, it is necessary to prepare the premix again for construction, and the remaining premix shall not be used.

[0029] In some embodiments of the present invention, in step 3, steel fibers with a length of 20 to 50 mm may be added according to engineering requirements, and the raw materials of the repair material include 30 to 60 parts by weight of steel fibers.

[0030] Due to the adoption of the above technical scheme, compared with the prior art, the benefits of the present invention are as follows: a concrete road repair method of the present invention verifies the dosage of the admixture in the raw materials of the repair material, and adaptively adjusts the dosage of the admixture according to the change in temperature, thereby ensuring that the road repair material has long-term collapse-resistant performance, does not require on-site mixing of concrete, and can quickly solidify after pouring, thereby effectively shortening the construction period and saving production costs. At the same time, it can also make the repaired concrete road have better strength. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0032] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0033] Example 1

[0034] In parts by weight, the raw materials of the repair material in this embodiment are composed of 290 parts of silicate cement, 200 parts of sulphoaluminate cement, 25 parts of gypsum, 30 parts of fly ash; 1000 parts of coarse aggregate, 800 parts of fine aggregate; 1 part of flow regulator, 1 part of water retaining agent, 1 part of early strength agent; 5 parts of polycarboxylic acid water reducer, 7 parts of sulphoaluminate retarder (at room temperature of 25°C), 1 part of tartaric acid; 60 parts of steel fiber and 150 parts of water.

[0035] Among them, the silicate cement is silicate cement with PO 52.5; the sulphoaluminate cement adopts sulphoaluminate cement with SAC52.5; the gypsum is anhydrite; the admixture is fly ash; the fine aggregate is river sand with a particle size of less than 4.75mm and continuous graded; the coarse aggregate is crushed stone with a particle size of 5-25mm and continuous graded; the steel fiber is a 4cm long coarse steel fiber.

[0036] This embodiment provides a concrete road repair method under the condition of 5°C in winter, comprising the following steps:

[0037] Step 1: Verify the dosage of sulphoaluminate retarder and polycarboxylate water reducer in the raw materials of the repair material. The air temperature in this embodiment is 20°C lower than the reference temperature. Accordingly, the dosage of sulphoaluminate retarder is reduced from 7 parts of the reference temperature to 5 parts (the dosage of sulphoaluminate retarder is reduced by 28.6%) to avoid excessive content of sulphoaluminate retarder and insufficient concrete strength. In addition, the dosage of water reducer is adjusted by trial mixing, as long as the initial fluidity of the concrete is controlled between 180 and 220 mm, it meets the requirements.

[0038] Step 2: Put 290 parts of Portland cement, 200 parts of sulphoaluminate cement, 25 parts of gypsum, 30 parts of fly ash, 1000 parts of coarse aggregate and 800 parts of fine aggregate into a concrete mixer and stir for 60 seconds until evenly mixed to obtain a premix.

[0039] Step 3: Add 1 part of flow regulator, 1 part of water retaining agent, 15 parts of early strength agent, 1 part of polycarboxylic acid water reducer, 7 parts of sulphoaluminate retarder, 1 part of tartaric acid and 150 parts of water into the premix in step 2 and stir for 300 seconds until the system reaches a colloidal state, then add 60 parts of steel fiber into the concrete mixer and mix thoroughly to obtain a premix.

[0040] Step 4: Place the premixed material in step 3 in a tank truck, transport it to the construction site and pour it to the location where the road surface needs to be repaired, and vibrate it with a vibrating rod to increase the working performance of the concrete; and perform a finishing operation within 3 hours after the pouring is completed. No watering maintenance can be performed after the finishing operation.

[0041] Among them, during the transportation of premixed materials, the tank body of the tank truck needs to rotate slowly and continuously; the first surface finishing needs to be carried out in time.

[0042] Step 5: Complete the secondary finishing before the concrete begins to set and within 4 hours after pouring to ensure a smooth concrete surface.

[0043] Step 6: After the final setting of the concrete, water it and cover it with film for maintenance; after the final setting, the concrete surface turns white and has initial hardness.

[0044] Step 7: For the premix prepared in step 3, if it is not used for more than 3 hours after it is obtained, this part of the premix cannot be used any more. It is necessary to add 100 kg of water and 5-10 kg of sulphoaluminate retarder to this part of the premix to scrap it. It cannot be left in the concrete tanker or other means of transportation.

[0045] The repaired position in this embodiment can solidify within 4 hours after repair, and the strength reaches 35MPa within 6-8 hours, meeting the requirements for traffic. In addition, the repair material is in premixed form and does not need to be mixed at the construction site, which can effectively shorten the road closure time. In addition, due to the low temperature, while reducing the dosage of sulphoaluminate retarder, the strength of the repair material is also guaranteed to avoid waste of raw materials.

[0046] Example 2

[0047] At the reference temperature, the amount of raw materials used in this embodiment is the same as that of the raw materials used in Example 1. Unlike Example 1, this embodiment provides a concrete road repair method under the condition of 35°C in summer, comprising the following steps:

[0048] Step 1: Verify the dosage of sulphoaluminate retarder and polycarboxylate water reducer in the raw materials of the repair material. The air temperature in this embodiment is 30°C higher than the reference temperature. Accordingly, the dosage of sulphoaluminate retarder is increased from 7 parts of the reference temperature to 9 parts (the dosage of sulphoaluminate retarder is increased by 28.6%) to avoid the slump retention time being insufficient due to the low content of sulphoaluminate retarder, and the concrete solidifies prematurely. Similarly, the dosage of water reducer is adjusted by trial mixing so that the initial fluidity of the concrete is controlled between 180 and 220 mm, which meets the requirements.

[0049] Step 2: Put 290 parts of Portland cement, 200 parts of sulphoaluminate cement, 25 parts of gypsum, 30 parts of fly ash, 1000 parts of coarse aggregate and 800 parts of fine aggregate into a concrete mixer and stir for 60 seconds until evenly mixed to obtain a premix.

[0050] Step 3: Add 1 part of flow regulator, 1 part of water retaining agent, 1 part of early strength agent, 5 parts of polycarboxylate water reducer, 9 parts of sulphoaluminate retarder, 1 part of tartaric acid and 150 parts of water into the premix in step 2 and stir for 300 seconds until the system reaches a colloidal state, then add 60 parts of steel fiber into the concrete mixer and mix thoroughly to obtain a premix.

[0051] Step 4: Place the premixed material in step 3 in a tank truck, transport it to the construction site and pour it to the location where the road surface needs to be repaired, and vibrate it with a vibrating rod to increase the working performance of the concrete; and perform a finishing operation within 3 hours after the pouring is completed. No watering maintenance can be performed after the finishing operation.

[0052] Among them, during the transportation of premixed materials, the tank body of the tank truck needs to rotate slowly and continuously; the first surface finishing needs to be carried out in time.

[0053] Step 5: Complete the secondary finishing before the concrete begins to set and within 4 hours after pouring to ensure a smooth concrete surface.

[0054] Step 6: After the final setting of the concrete, water it and cover it with film for maintenance; after the final setting, the concrete surface turns white and has initial hardness.

[0055] Step 7: For the premix prepared in step 3, if it is not used for more than 3 hours after it is obtained, this part of the premix cannot be used any more. It is necessary to add water and sulphoaluminate retarder to this part of the premix to scrap it. It cannot be left in the concrete tanker or other means of transportation.

[0056] The repaired position in this embodiment can solidify within 3.5 hours after repair, and the strength reaches 35MPa within 6-8 hours, meeting the traffic requirements, which can effectively shorten the road closure time. In addition, due to the increase in temperature, it is necessary to appropriately increase the dosage of sulphoaluminate retarder to avoid the construction being affected by the premature solidification of concrete during the construction process, and also to avoid the loss of repair materials.

[0057] The concrete road repair method of the present invention verifies the dosage of the admixture in the raw materials of the repair material before repairing the road, mainly to adaptively adjust the dosage of the admixture according to the change of temperature, so as to ensure that the road repair material has a long-term collapse-resistant performance, does not need to mix concrete on site, and can quickly solidify after pouring, thereby effectively shortening the construction period and saving production costs. At the same time, the repaired concrete road can also have better strength.

[0058] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A concrete road repair method, characterized in that: The concrete road is repaired using a repair material, wherein the raw material of the repair material contains an admixture, and the concrete road repair method comprises the following steps: Verify the dosage of the admixture in the raw materials of the repair material, and mix the raw materials in proportion to obtain a premix according to the verification result; transport the premix to the construction site and pour it to the required construction position, and then perform finishing, maintenance and scrapping of part of the premix.

2. The concrete road repair method according to claim 1, characterized in that: The admixture includes a sulphoaluminate retarder and a first component, wherein the first component includes a water reducing agent.

3. The concrete road repair method according to claim 2, characterized in that: The method for verifying the dosage of the admixture in the raw material of the repair material is: verifying the dosage of the sulphoaluminate retarder in the admixture and the dosage of the water reducing agent in the first component.

4. The concrete road repair method according to claim 3, characterized in that: The method for verifying the dosage of the sulphoaluminate retarder in the admixture is: determining a reference temperature, when the ambient temperature during concrete road repair is compared with the reference temperature, the change rate of the sulphoaluminate retarder dosage is 10% to 30% for every 15°C change.

5. The method for repairing a concrete road according to claim 4, characterized in that: When the ambient temperature during concrete road repair is compared with the reference temperature, the dosage of the sulphoaluminate retarder is reduced by 10% to 30% for every 15°C decrease; and the dosage of the sulphoaluminate retarder is increased by 10% to 30% for every 15°C increase.

6. The method for repairing a concrete road according to claim 5, characterized in that: When at the reference temperature, the admixture includes 3 to 10 parts of sulphoaluminate retarder.

7. The concrete road repair method according to claim 6, characterized in that: The reference temperature is room temperature, and the room temperature is 20-30°C.

8. The method for repairing a concrete road according to claim 1, characterized in that: The raw materials of the repair material also include composite cementitious materials, aggregates, characteristic components and water. The method of mixing the raw materials in proportion to obtain the premix is: The composite cementitious material and aggregate in the raw materials of the verified repair material are mixed evenly in proportion to obtain a premix; then the characteristic components, admixtures and water in the raw materials of the repair material are added into the premix in proportion and mixed evenly to obtain the premix.

9. The concrete road repair method according to claim 1, characterized in that: The finishing includes primary finishing and secondary finishing. The secondary finishing must be completed before the initial setting of the concrete and within 4 hours after the pouring is completed.

10. The concrete road repairing method according to claim 2, characterized in that: The method for scrapping the part of the premix is: after obtaining the premix, for the part of the premix that has not been used for more than 3 hours, water and the sulphoaluminate retarder are added to the part of the premix to scrap it.