Pier column maintenance method in high-altitude and high-severe-cold area

Abstract

The invention relates to the technical field of concrete pier column maintenance, and discloses a high-altitude high-severe-cold area pier column maintenance method which comprises the following steps: step 1, before pier column form removal, covering a pier top with geotechnical cloth, and arranging fixed automatic spraying maintenance equipment on the pier top so as to enable the pier top to infiltrate a pier body; 2, when the pier column is demoulded, pier body formworks are demoulded step by step from top to bottom, and after each layer of formwork is demoulded, the formwork is wrapped with a composite geomembrane and tightened with a rope; and 3, after the pier column is demoulded, steam curing equipment is built on the outer side of the pier column and used for further curing the pier column. The pier stud maintenance method provided by the invention has very strong practical engineering significance on railway pier stud maintenance in high-altitude and high-severe-cold areas, and meets the requirements of safe and civilized construction on site. Compared with a traditional pier column maintenance measure, the construction method has the advantages that the concrete quality and project safety are ensured, the project quality is comprehensively guaranteed, the construction efficiency is improved, and the maintenance cost of pier column construction is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of concrete pier column maintenance, and in particular to a pier column maintenance method in high-altitude and severe cold areas. Background Art

[0002] The significant temperature difference between day and night is a unique climatic condition in the plateau area. Facing such temperature difference changes, it will have a serious adverse impact on the quality of concrete construction. In particular, when the temperature difference in the concrete surface is large, it is easy to cause cracks in the pier body and other quality problems, which in turn affects the overall safety and stability of the pier body.

[0003] Therefore, after the pier body concrete pouring is completed, in order to ensure the quality of concrete and project safety, it is necessary to select appropriate wrapping materials and scientific maintenance methods. This is not only a strict control of construction quality, but also a comprehensive guarantee of project quality. Through the combination of carefully selected wrapping materials and professional maintenance technology, the project will effectively reduce the impact of temperature difference on concrete, ensure the integrity and strength of the pier body, and provide solid technical support for the smooth progress of the project. At the same time, this can also improve construction efficiency, reduce subsequent maintenance costs, and ensure the maximization of the economic and social benefits of the project. Summary of the invention

[0004] In order to solve the technical problems raised in the background technology, the present invention provides a pier column maintenance method in high-altitude and severe cold areas.

[0005] The present invention is implemented by the following technical solution: A method for maintaining pier columns in high-altitude and severe cold areas, comprising the following steps:

[0006] Step 1: Before removing the formwork of the pier column, cover the top of the pier with geotextile and install a fixed automatic spraying maintenance device on the top of the pier to allow the top of the pier to soak the pier body;

[0007] Step 2: When removing the formwork of the pier column, gradually remove the pier body formwork from top to bottom. After each layer of formwork is removed, wrap it with a composite geomembrane and secure it with ropes;

[0008] Step 3: After the pier is demoulded, a steam curing device is built on the outside of the pier for further curing of the pier.

[0009] As a further improvement of the above solution, the curing time before the pier column is demolded should not be less than 72 hours.

[0010] As a further improvement of the above solution, the composite geomembrane adopts ropes with one hoop arranged every 1m in the horizontal and vertical directions to form a rope net for encryption and tightening.

[0011] As a further improvement of the above scheme, the steam curing equipment includes a curing scaffolding built on the periphery of the pier, an insulation layer wrapped on the outside of the curing scaffolding, a wireless monitoring module installed inside the scaffolding, a steam delivery module and a steam generating module arranged outside the scaffolding; wherein:

[0012] The maintenance scaffold is formed by stacking several sets of modular unit frames step by step.

[0013] The thermal insulation layer is formed by a plurality of thermal insulation blankets wrapped around the outside of the curing scaffold, and the gaps between adjacent thermal insulation blankets are pressed and bonded together;

[0014] The wireless monitoring module includes a temperature and humidity sensor for detecting the temperature and humidity of the periphery of the pier in the maintenance scaffold;

[0015] The steam delivery module includes a steam delivery pipeline installed inside the maintenance scaffold;

[0016] The steam generation module comprises a steam generator using electricity as energy, and the output end of the steam generator is connected to the air inlet port of the steam delivery pipeline.

[0017] As a further improvement of the above scheme, the unit frames are clamped together by an intermediate fixing mechanism and a corner fixing mechanism to facilitate the installation and later disassembly of the frames, and the intermediate fixing mechanism is used to fix from the middle of two adjacent groups of unit frames, and the corner fixing mechanism is used to fix from the corners of two adjacent groups of unit frames.

[0018] As a further improvement of the above solution, the intermediate fixing mechanism includes a U-shaped bolt, a pad movably mounted on the end of the U-shaped bolt, and locking nuts respectively screwed on both ends of the U-shaped bolt.

[0019] As a further improvement of the above scheme, the corner fixing mechanism also includes an alignment module based on the middle fixing mechanism, and the alignment module package includes a connecting plate, a fixed plate, a rotating plate and two clamping plates, one end of the connecting plate is used to connect with one end of the U-shaped bolt, the other end of the connecting plate is connected to the fixed plate, the rotating plate is rotatably installed in the middle of the connecting plate, the two clamping plates are respectively rotatably connected to the upper and lower ends of the fixed plate, and the movable ends of the two clamping plates are provided with through holes.

[0020] As a further improvement of the above solution, a through hole is opened in the middle of the connecting plate, a screw is fixed in the middle of one side of the rotating plate, and the end of the screw moves through the through hole and an adjusting nut is screwed on it.

[0021] As a further improvement of the above scheme, the connecting plate, fixed plate, rotating plate and clamping plate are all stainless steel plates. In terms of thickness, the connecting plate>rotating plate>fixed plate>clamping plate. The thickness of the clamping plate is greater than 5 mm, and the thickness of the connecting plate is less than 2 cm.

[0022] As a further improvement of the above scheme, the steam delivery pipeline includes a plurality of annular delivery pipes and a plurality of vertical delivery pipes, the plurality of annular delivery pipes are respectively connected to each unit skeleton, the plurality of vertical delivery pipes are used to connect the annular delivery pipes in series, and the annular delivery pipes and the plurality of vertical delivery pipes are provided with a plurality of steam outlets, the annular delivery pipe located at the bottom is externally connected to a high-temperature resistant connecting hose, and the other end of the connecting hose is used to be connected to the output end of the steam generator.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The pier maintenance method proposed in the present invention has great practical engineering significance for the maintenance of railway piers in high-altitude and severe cold areas, and meets the requirements of safe and civilized construction on site. Compared with traditional pier maintenance measures, this method ensures the quality of concrete and project safety, and the quality of the project is fully guaranteed, which not only improves the construction efficiency, but also reduces the maintenance cost of pier construction.

[0025] The steam maintenance equipment proposed in the present invention is convenient and quick to install and build, and can perform all-round maintenance on piers constructed in high-altitude and severe cold areas. It can perform maintenance construction on piers of different sizes and heights, and has wide applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a flow chart of the pier column maintenance method in high altitude and severe cold regions proposed by the present invention;

[0027] Figure 2 This is a schematic diagram of the front structure of the maintenance scaffolding proposed by the present invention;

[0028] Figure 3 This is a schematic diagram of the structure of the maintenance scaffolding proposed by the present invention after it is built outside the pier column;

[0029] Figure 4 This is a schematic diagram of the three-dimensional structure of the corner when the unit skeleton proposed by the present invention is spliced ​​and observed from the outside;

[0030] Figure 5 For the present invention Figure 4 A magnified image of point A;

[0031] Figure 6 This is a schematic diagram of the three-dimensional structure of the corner when the unit skeleton proposed by the present invention is spliced ​​and viewed from the inside;

[0032] Figure 7For the present invention Figure 6 The enlarged view of point B;

[0033] Figure 8 A top view of the foundation construction of the maintenance scaffolding proposed by the present invention;

[0034] Fig. 9 It is an installation elevation view of the bottom frame and foundation of the maintenance scaffolding of the present invention;

[0035] Fig.10 This is a real picture of the steam maintenance equipment of the present invention after installation.

[0036] Description of main symbols:

[0037] Maintenance scaffolding 1, unit skeleton 110, insulation layer 2, steam delivery pipeline 3, vertical delivery pipe 310, annular delivery pipe 320, clamp 330, pier 5, steam generating module 6, intermediate fixing mechanism 7, corner fixing mechanism 8, U-bolt 9, locking nut 10, pad 11, connecting plate 13, notch 12, clamping plate 14, fixing plate 15, rotating plate 16, screw 17, through hole 18, connecting part 19, notch 20. DETAILED DESCRIPTION

[0038] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0039] Embodiment 1:

[0040] Reference Figure 1-Figure 7 The present invention proposes a maintenance method for pier columns 5 in high altitude and severe cold regions, comprising the following steps:

[0041] Step 1: Before removing the formwork of the pier column 5, cover the top of the pier with geotextile, and install a fixed automatic spraying maintenance device on the top of the pier to make the top of the pier soak into the pier body;

[0042] Step 2: When removing the formwork of pier column 5, gradually remove the pier body formwork from top to bottom. After each layer of formwork is removed, wrap it with a composite geomembrane and secure it with ropes;

[0043] Step 3: After the pier 5 is demoulded, a steam curing device is built outside the pier 5 to further maintain the pier 5.

[0044] As an optional implementation scheme of the present invention, the curing time of the pier 5 before demolding should not be less than 72 hours.

[0045] During specific operation, the composite geomembrane is wrapped tightly by arranging a binding hoop every 1m in the horizontal and vertical directions of the rope to form a rope net.

[0046] Optionally, the steam curing equipment includes a curing scaffold 1 built on the periphery of the pier 5, an insulation layer 2 wrapped on the outside of the curing scaffold 1, a wireless monitoring module installed inside the scaffold, a steam delivery module, and a steam generating module arranged outside the scaffold; wherein:

[0047] The maintenance scaffold 1 is formed by stacking a plurality of modular unit frames 110 step by step upwards;

[0048] The insulation layer 2 is formed by a plurality of insulation blankets wrapped around the outside of the curing scaffold 1, and the gaps between adjacent insulation blankets are pressed and bonded;

[0049] The wireless monitoring module includes a temperature and humidity sensor for detecting the temperature and humidity of the periphery of the pier 5 in the maintenance scaffold 1;

[0050] The steam delivery module comprises a steam delivery pipeline 3 installed inside the curing scaffold 1;

[0051] The steam generation module 6 includes a steam generator using electricity as energy, and the output end of the steam generator is connected to the air inlet port of the steam delivery pipeline 3 .

[0052] In this solution, the unit skeletons 110 are clamped together by an intermediate fixing mechanism 7 and a corner fixing mechanism 8 to facilitate the installation and later disassembly of the skeleton, and the intermediate fixing mechanism 7 is used to fix from the middle of two adjacent groups of unit skeletons 110, and the corner fixing mechanism 8 is used to fix from the corners of two adjacent groups of unit skeletons 110.

[0053] It should be noted that the intermediate fixing mechanism 7 includes a U-shaped bolt 9, a backing plate 11 movably sleeved at the end of the U-shaped bolt 9, and locking nuts 10 respectively screwed on both ends of the U-shaped bolt 9.

[0054] Furthermore, the corner fixing mechanism 8 also includes an alignment module based on the intermediate fixing mechanism 7, and the alignment module includes a connecting plate 13, a fixed plate 15, a rotating plate 16 and two clamping plates 14. One end of the connecting plate 13 is used to connect with one end of the U-shaped bolt 9, and the other end of the connecting plate 13 is connected to the fixed plate 15. The rotating plate 16 is rotatably installed in the middle of the connecting plate 13. Specifically, a notch 12 for accommodating the rotating plate 16 is provided in the middle of the connecting plate 13. The two clamping plates 14 are respectively rotatably connected to the upper and lower ends of the fixed plate 15, and the movable ends of the two clamping plates 14 are provided with through holes 18.

[0055] Furthermore, a through hole is formed in the middle of the connecting plate 13, a screw rod 17 is fixed in the middle of one side of the rotating plate 16, and the end of the screw rod 17 moves through the through hole and is screwed with an adjusting nut (not shown).

[0056] As a further improvement of the above scheme, the connecting plate 13, the fixed plate 15, the rotating plate 16 and the clamping plate 14 are all stainless steel plates. In terms of thickness, the connecting plate 13>rotating plate 16>fixed plate 15>clamping plate 14, the thickness of the clamping plate 14 is greater than 5 mm, and the thickness of the connecting plate 13 is less than 2 cm.

[0057] It is worth mentioning that the steam delivery pipeline 3 includes a plurality of annular delivery pipes 320 and a plurality of vertical delivery pipes 310, the plurality of annular delivery pipes 320 are respectively connected to each unit frame 110, the plurality of vertical delivery pipes 310 are used to connect the annular delivery pipes 320 in series, and the annular delivery pipes 320 and the plurality of vertical delivery pipes 310 are provided with a plurality of steam outlets, the annular delivery pipe 320 located at the bottom is externally connected with a high temperature resistant connecting hose, the other end of the connecting hose is used to be connected to the output end of the steam generator, and the annular delivery pipe 320 is connected and fixed to the unit frame by a clamp 330 for easy installation and disassembly.

[0058] Reference Figure 8-Figure 10 , more specifically, the following is explained with examples of specific application scenarios:

[0059] The present invention proposes a pier column maintenance method for high-altitude and severe cold regions, including pre-demolding maintenance and post-demolding maintenance; after the concrete pouring of the bridge pier body is completed, it is necessary to carry out maintenance with the formwork, that is, pre-demolding maintenance, and the maintenance time before demolding should not be less than 72 hours; before demolding, the sprinkler pipe and suspension system are installed in advance on the pier top, and the water pipe joint is reserved; when demolding, the pier body formwork is gradually removed from top to bottom, and each time a layer of formwork is removed, it is wrapped with a composite geomembrane and secured with ropes. The wrapping principle is "one mold, two layers, and grid layout", that is, a rope is used to arrange a binding hoop every 1m horizontally, and a grid is used to encrypt and wrap it vertically;

[0060] The following measures are adopted in the maintenance stage before demolding:

[0061] Cover the top of the pier with geotextile and install fixed automatic spraying maintenance equipment on the top of the pier to make the top of the pier soak into the pier body;

[0062] The following measures are adopted in the maintenance stage after demolding:

[0063] The "water energy curing membrane + two cloths and one membrane" is used to wrap the outside of the pier column and tied firmly with ropes. This wrapping method can ensure that the pier body is tightly wrapped while ensuring beauty, reducing the impact of external factors such as strong winds on the pier body. The impermeable material composed of geotextiles and geomembranes has high physical and mechanical performance indicators such as tensile resistance, tear resistance, and bursting resistance, and has the advantages of UV protection and non-aging. The wrapping and curing time is no less than 6 months.

[0064] The specific operations are as follows:

[0065] When removing the formwork, the pier body formwork is gradually removed from top to bottom. After each layer of formwork is removed, it is wrapped with a composite geomembrane and secured with ropes. The wrapping principle is "one formwork, two lines, grid layout", that is, a rope is used to tie the pier body every 1m horizontally, and a grid is used to tighten the pier body vertically.

[0066] Wrap multiple layers of thermal insulation film on the outside of the pier to isolate the pier from the surrounding environment;

[0067] A wireless monitoring system is installed on the outside of the pier to monitor the concrete core, surface temperature and strain history in real time;

[0068] Steam maintenance equipment is installed on the outside of the pier, and the steam maintenance equipment performs adaptive work according to the results monitored by the wireless monitoring system;

[0069] The above steam curing equipment includes the following steps during the specific construction:

[0070] Pier body steam curing scaffolding construction:

[0071] 1. Foundation treatment; (with attached pictures), refer to Figure 8 .

[0072] After the foundation is leveled, drainage should be done around the foundation to prevent water accumulation. The bearing capacity should not be less than 120kPa. The strip foundation is cast in 1m*0.5mC30 concrete with a center size of 8.4*4.1m; φ12L steel bars are embedded in the corresponding columns in the foundation. After pouring, the surface is leveled;

[0073] 2. Processing of maintenance shed skeleton modules;

[0074] All steel components should be placed on a 1:1 construction sample before production, and the material can only be cut after verification. Steel materials should be calibrated before processing to make them flat, so as not to affect the production accuracy;

[0075] The 8.4×2m long side module columns and crossbars are welded with 100×50×3mm steel, and the diagonal braces are welded with 50×50×3mm angle steel;

[0076] 4.1×2m long side module columns and crossbars are welded with 100×50×3mm steel, and diagonal braces are welded with 50×50×3mm angle steel;

[0077] 3. Installation of the maintenance shed base, refer to Fig. 9 .

[0078] Install the bottom layer of the frame on the strip foundation base and weld it with the embedded steel bars and columns.

[0079] 4. Template assembly;

[0080] After the base is installed, the upper modular assembly is carried out in sequence, and the angle steel is pre-welded between the columns.

[0081] 5. Segment closure and heightening

[0082] Connect the two sets of long sides and the two sets of short sides with bolts to form a four-sided closed circle. During installation, ensure that the verticality of the poles is within 1‰. Follow the steps one by one and install the maintenance shed layer by layer to the preset working height.

[0083] 6. The scaffolding construction is completed.

[0084] Insulation is installed

[0085] The vertical height of the insulation blanket is 2m per section. After the maintenance shed frame is installed, the insulation blanket is installed on its outside. The insulation blanket has self-adhesive adhesive on the outside to facilitate the connection of each section. Fig.10 The specific effect after the insulation is installed is shown in the figure.

[0086] Intelligent temperature and humidity control module

[0087] The intelligent temperature and humidity control system is the core part of the pier body construction and maintenance system. It consists of a temperature and humidity controller, a sensor, and a heating and humidification system. The controller is used to intelligently control and adjust the temperature and humidity of the maintenance area.

[0088] Temperature and humidity sensors are installed in the steam curing shed to monitor the temperature and humidity in real time. The equipment automatically adjusts the temperature and humidity according to the data. The humidity of the steam shed is controlled above 90%, and the internal temperature is kept uniform and not lower than 10℃, and should not be higher than 25℃;

[0089] Intelligent temperature and humidity execution module

[0090] Steam is introduced into the insulation system (i.e. the shed covered with insulation blanket) through pipes. The steam delivery pipeline is arranged according to the temperature change law and fluidity in the sealed space.

[0091] The pier body is steam cured for 9 days and then wrapped with film + geotextile.

[0092] The pier body curing equipment adopts a fully automatic temperature control system, which monitors the temperature and humidity in real time and automatically adjusts the temperature and humidity. During the steam curing of the pier body, the on-site quality inspector will inspect it four times a day and record the temperature, humidity and sealing condition of the curing shed.

[0093] The water storage tank for steaming the pier body is filled with water once every morning at 8:00 and afternoon at 2:00.

[0094] After steam curing is completed, the curing records and data shall be submitted to the information room for archiving.

[0095] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A method for maintaining pier columns in high altitude and severe cold regions, characterized in that: The steps include: Step 1: Before removing the formwork of the pier column, cover the top of the pier with geotextile and install a fixed automatic spraying maintenance device on the top of the pier to allow the top of the pier to soak the pier body; Step 2: When removing the formwork of the pier column, gradually remove the pier body formwork from top to bottom. After each layer of formwork is removed, wrap it with a composite geomembrane and secure it with ropes; Step 3: After the pier is demoulded, a steam curing device is built on the outside of the pier for further curing of the pier.

2. The method for maintaining pier columns in high altitude and severe cold regions according to claim 1, characterized in that: The curing time before the pier is demoulded should not be less than 72 hours.

3. The method for maintaining pier columns in high altitude and severe cold regions according to claim 1, characterized in that: The composite geomembrane adopts ropes to arrange a binding hoop every 1m horizontally and vertically to form a rope net for encryption and tightening.

4. The method for maintaining pier columns in high altitude and severe cold regions according to claim 1, characterized in that: The steam curing equipment includes a curing scaffolding built on the periphery of the pier, a heat preservation layer wrapped on the outside of the curing scaffolding, a wireless monitoring module installed inside the scaffolding, a steam delivery module and a steam generation module arranged outside the scaffolding; wherein: The maintenance scaffold is formed by stacking several sets of modular unit frames step by step. The thermal insulation layer is formed by a plurality of thermal insulation blankets wrapped around the outside of the curing scaffold, and the gaps between adjacent thermal insulation blankets are pressed and bonded together; The wireless monitoring module includes a temperature and humidity sensor for detecting the temperature and humidity of the periphery of the pier in the maintenance scaffold; The steam delivery module includes a steam delivery pipeline installed inside the maintenance scaffold; The steam generation module comprises a steam generator using electricity as energy, and the output end of the steam generator is connected to the air inlet port of the steam delivery pipeline.

5. The method for maintaining pier columns in high altitude and severe cold regions as claimed in claim 1, characterized in that: The unit frames are connected by intermediate fixing mechanisms and corner fixing mechanisms to facilitate installation and later disassembly of the frames. The intermediate fixing mechanisms are used to fix from the middle of two adjacent groups of unit frames, and the corner fixing mechanisms are used to fix from the corners of two adjacent groups of unit frames.

6. The method for maintaining pier columns in high altitude and severe cold regions as claimed in claim 1, characterized in that: The intermediate fixing mechanism comprises a U-shaped bolt, a pad movably sleeved on the end of the U-shaped bolt, and locking nuts respectively screwed on both ends of the U-shaped bolt.

7. The method for maintaining pier columns in high altitude and severe cold regions as claimed in claim 1, characterized in that: The corner fixing mechanism also includes an alignment module based on the middle fixing mechanism. The alignment module includes a connecting plate, a fixed plate, a rotating plate and two clamping plates. One end of the connecting plate is used to connect with one end of the U-shaped bolt, and the other end of the connecting plate is connected to the fixed plate. The rotating plate is rotatably installed in the middle of the connecting plate. The two clamping plates are respectively rotatably connected to the upper and lower ends of the fixed plate, and the movable ends of the two clamping plates are provided with through holes.

8. The method for maintaining pier columns in high altitude and severe cold regions as claimed in claim 1, characterized in that: A through hole is opened in the middle of the connecting plate, a screw is fixed in the middle of one side of the rotating plate, and the end of the screw movably passes through the through hole and is spirally installed with an adjusting nut.

9. The method for maintaining pier columns in high altitude and severe cold regions as claimed in claim 1, characterized in that: The connecting plate, fixed plate, rotating plate and clamping plate are all stainless steel plates. In terms of thickness, the connecting plate is greater than the rotating plate, the fixed plate is greater than the clamping plate, and the thickness of the clamping plate is greater than 5 mm, and the thickness of the connecting plate is less than 2 cm.

10. The method for maintaining pier columns in high altitude and severe cold regions according to claim 1, characterized in that: The steam delivery pipeline includes a plurality of annular delivery pipes and a plurality of vertical delivery pipes, wherein the plurality of annular delivery pipes are respectively connected to each unit frame, and the plurality of vertical delivery pipes are used to connect the annular delivery pipes in series, and the annular delivery pipes and the plurality of vertical delivery pipes are each provided with a plurality of steam outlets, and the annular delivery pipe located at the bottom is externally connected with a high-temperature resistant connecting hose, and the other end of the connecting hose is used to be connected to the output end of the steam generator.

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