Construction method of small, medium and large square reserved hole in radiation-proof structure

Abstract

This invention discloses a construction method for small to medium-sized square pre-reserved openings in a radiation-shielding structure. The method includes processing a molded iron box using steel plates according to the opening dimensions; arranging crisscrossing longitudinal and transverse reinforcing ribs on the outer surface of the iron box; adding an internal support in the middle of the square opening; sealing both ends of the iron box with multiple plastic bags before installation; setting a trapezoidal support frame at the lower part of the pre-embedded design position of the iron box and fixing the iron box to the trapezoidal frame; simultaneously arranging a steel wire mesh on the upper part of the iron box to reduce direct impact from concrete; after the radiation-shielding structure is cast, equipment is inserted first, and after equipment debugging, the gap between the equipment and the iron box is pre-sealed with barite mortar, reserving grouting ports and overflow ports, followed by injection of cement grout; after grouting, the surface is reinforced with lead plates for radiation protection. This invention can better control the precision of reserving small to medium-sized square pre-reserved openings and has high construction quality stability.

Description

Technical Field

[0001] This invention relates to the field of construction of small and medium-sized square reserved openings in the building industry, and specifically to a method for constructing small and medium-sized square reserved openings in a radiation protection structure. Background Technology

[0002] With rapid societal development and rising living standards, the demand for medical services has increased. To better serve cancer patients, many hospitals have equipped themselves with advanced radiotherapy equipment—heavy ion or proton linear accelerators. Radiotherapy using heavy ion or proton linear accelerators generates a large amount of radiation. To reduce radiation hazards, the accelerator area is reinforced with numerous ultra-thick concrete walls, 2-4 meters high. These concrete walls require precise precision and numerous openings for heavy ion equipment processes, electromechanical pipelines, etc. Due to the large wall thickness and the fact that they are all cast-in-place concrete structures, many traditional construction methods for pre-reserved openings are not feasible, especially in the construction of medium and small square openings. Firstly, the interior lacks the necessary facilities for personnel to operate, making the use of wooden formwork difficult and impossible to remove later. Secondly, the construction of square openings differs from that of round openings. Round openings, due to their good load-bearing capacity, can be pre-embedded using sleeves of matching sizes, and various ready-made round sleeves are readily available on the market. However, square openings have poor load-bearing capacity, are easily deformed, and it is difficult to purchase suitable ready-made structures on the market. Thirdly, medium and small square openings (cross-sectional dimensions 300~600 mm) are relatively large in size, easily deformed, and extremely difficult to install, so it is necessary to use materials with high rigidity and light weight. Fourthly, radiation protection sealing is required after the equipment is inserted into the opening. Summary of the Invention

[0003] Based on the above practical problems, the purpose of this invention is to provide a construction method for medium and small square reserved openings in radiation protection structures that has reliable construction accuracy, convenient installation and relatively low construction cost, so as to meet the construction needs of medium and small square reserved openings in radiation protection structures.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A construction method for medium and small square reserved openings in a radiation protection structure, comprising the following steps: Step 1: Measure the dimensions of the square opening, and process the mold box using a steel plate according to the opening dimensions. The inner diameter of the iron box is slightly larger than the opening dimensions. Step 2: Arrange longitudinal and transverse reinforcing ribs on the outer surface of the iron box, and spot weld the reinforcing ribs together. The distance between the transverse and / or longitudinal reinforcing ribs and the iron box spot welds shall not be greater than 10cm. Step 3: When the side cross-sectional dimension of the square opening is greater than 600mm, add an internal support in the middle of the square opening and fix it with light spot welding; Step 4: Before installing the metal box, seal both ends with multiple plastic bags; Step 5: Install a trapezoidal support frame at the lower part of the pre-embedded design position of the iron box, fix the iron box to the trapezoidal support frame, and then arrange horizontal and vertical opening reinforcements in the structural reinforcement around the iron box to constrain the longitudinal and lateral displacement of the opening. Step 6: At the same time, install a steel wire mesh at a height of 50cm above the iron box to reduce the direct impact of concrete. Step 7: When pouring concrete, control the pouring height to not exceed 3 meters. When the concrete falls, it is strictly forbidden to directly impact the pipe. When vibrating the concrete, keep the vibrator 10cm away from the iron box. Step 8: After the radiation shielding structure is cast and formed, insert the equipment first. After the equipment is debugged, seal the gap between the equipment and the iron box with barite mortar, leaving grouting ports and overflow ports. Then inject cement grout. After grouting is completed, add lead plates to the surface for radiation shielding reinforcement, extending 10cm on both the equipment and structure surfaces.

[0005] Optionally, in step 1, the mold box is made of 3mm steel plate, and the inner diameter of the box is slightly larger than the opening size by 2cm.

[0006] Optionally, in step 2, both the longitudinal reinforcing ribs and the transverse reinforcing ribs are made of Φ16 steel bars with a spacing of 400mm.

[0007] Optionally, in step 3, the spacing between adjacent inner supports is 400mm.

[0008] Optionally, in step 5, the trapezoidal support frame is a frame structure welded from support uprights, support longitudinal bars, and support horizontal bars, and the distance between two adjacent support uprights is no more than 600mm.

[0009] Furthermore, the support frame is welded from Φ18 steel bars.

[0010] Furthermore, in step 6, the wire mesh barrier is made of a Φ14 steel bar skeleton and a 4mm wire mesh connected together.

[0011] Optionally, in step 8, the lead plate is 20cm wide and 10mm thick.

[0012] Therefore, the present invention utilizes a square steel sleeve structure formed by fully welding prefabricated steel plates: Firstly, it can resist the deformation pressure caused by the ultra-high and ultra-thick concrete around the reserved opening when pouring concrete. Because the iron box is reinforced with steel bars and stirrups, it can also eliminate the potential deformation hazards that the vibrator may cause to the precast iron box to a certain extent.

[0013] Secondly, a protective mesh made of steel keel and wire mesh is arranged on the upper part of the iron box to reduce the impact of the falling concrete and avoid adverse effects on the pre-embedded sleeve.

[0014] Third, all pre-embedded openings are reinforced with steel bars to form trapezoidal support frames at the bottom. The support frames are spaced no more than 600mm apart, and the height of the support frames is set according to the bottom elevation of the opening to reduce the impact of downward deflection along the length.

[0015] Fourth, after the equipment is installed, barite mortar is used to seal the gap between the equipment and the mold, which can provide good radiation protection.

[0016] This invention can not only effectively enhance the overall stability of the formwork during the construction of structural openings, but also eliminates the need for formwork removal due to the material of the steel plate, protecting the external corners of the openings. Furthermore, the subsequent sealing with steel grit can effectively solve the problem of radiation leakage from gaps.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: According to the above technical solution, the present invention adopts a construction method with reliable construction accuracy, convenient installation and relatively low construction cost to solve the construction problem of medium and small square reserved openings in radiation protection structures. It can better control the reservation accuracy of medium and small square reserved openings, and the construction quality stability is relatively high.

[0018] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the mold for the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the mold for the present invention. Figure 2 ; Figure 3 This is a schematic diagram of the mold for the present invention. Figure 3 ; Figure 4 This is an elevation view of the mold mounting bracket of the present invention; Figure 5 This is a schematic diagram of the mold mounting bracket of the present invention. Figure 6 This is a schematic diagram of the steel wire barrier mesh of the present invention; Figure 7 This is a schematic diagram of the installation of the opening of the present invention. Figure 1 ; Figure 8 This is a schematic diagram of the installation of the opening of the present invention. Figure 2 ; Figure 9 This is a schematic diagram of the opening forming process of the present invention.

[0020] Among them, 1-3mm steel plate, 2-longitudinal reinforcing rib, 3-transverse reinforcing rib, 4-internal support, 5-support upright, 6-support longitudinal rod, 7-support horizontal rod, 8-opening reinforcing bar, 9-structural bar, 10-steel wire mesh, 11-steel skeleton, 12-steel wire mesh, 13-radiation protection structure, 14-cement grout, 15-barite mortar, 16-equipment, 17-lead plate, 18-welding. Detailed Implementation

[0021] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention. Example 1

[0022] A construction method for small to medium-sized square pre-reserved openings within a radiation shielding structure, such as... Figures 1 to 9 As shown, it includes the following steps: Step 1: Measure the dimensions of the square opening. Use a 3mm steel plate 1 to weld 18 along the four edges according to the opening dimensions to process the mold iron box. The inner diameter of the iron box is about 2cm larger than the opening size.

[0023] Step 2: The outer surface of the iron box is arranged with crisscrossing longitudinal reinforcing ribs 2 and transverse reinforcing ribs 3. Both longitudinal reinforcing ribs 2 and transverse reinforcing ribs 3 are made of Φ16 steel bars with a spacing of 400mm. The reinforcing ribs are spot welded together, and the spot weld distance between the transverse and / or longitudinal reinforcing ribs and the iron box is no more than 10cm.

[0024] Step 3: When the cross-sectional dimension of the square opening is greater than 600mm, add an inner support 4 in the middle of the square opening. The spacing between adjacent inner supports 4 is 400mm, and they can be fixed by light spot welding.

[0025] Step 4: Before installing the iron box, seal both ends with multiple plastic bags to prevent concrete slurry from flowing into the mold later.

[0026] Step 5: Install a trapezoidal support frame at the pre-embedded design position of the iron box. The trapezoidal support frame is welded with Φ18 steel bars. The support frame is a frame structure composed of support uprights 5, support longitudinal bars 6, and support horizontal bars 7. The distance between two adjacent support uprights 5 is no more than 600mm. After placing the iron box on the trapezoidal support frame and adjusting the position of the iron box to the design requirements, fix the iron box to the trapezoidal support frame. Then, arrange horizontal and vertical opening reinforcement bars 8 in the structural reinforcement bars 9 around the iron box. The opening reinforcement bars 8 are made of Φ14 steel bars to restrain the longitudinal and lateral displacement of the opening and reduce the possible deviation of the opening.

[0027] Step 6: At the same time, steel wire mesh 10 is arranged at a height of 50cm above the iron box to reduce the direct impact of concrete. The height is selected according to the deformation of the steel wire mesh and the influence of concrete pouring to ensure the accuracy of the opening. The steel wire mesh 10 is made of Φ14 steel bar skeleton 11 and 4mm steel wire mesh 12 connected together.

[0028] Step 7: When pouring concrete, control the pouring height to not exceed 3 meters; when concrete falls, it is strictly forbidden to directly impact the pipe; when vibrating concrete, keep the vibrator about 10cm away from the iron box.

[0029] Step 8: After the radiation shielding structure 13 is cast and formed, the equipment 16 is inserted first. After the equipment 16 is debugged, the gap between the equipment 16 and the iron box is sealed with barite mortar 15 in advance, and the grouting port and overflow port are reserved. Then, cement grouting liquid 14 is injected. After the grouting is completed, a 20cm wide and 10mm thick lead plate 17 is added to the surface for radiation shielding reinforcement, extending 10cm on both the equipment and structure surfaces.

[0030] In this embodiment, the barite mortar is composed of the following raw materials in parts by weight: cement: barite powder: barite sand: coarse sand = 1:0.25:2.5:1, wherein the barite sand particle size is within 1.2mm. The cement grouting fluid is composed of the following raw materials in parts by weight: cement: sand: water: expanding agent = 1:2:0.5:0.1, wherein the expanding agent is sodium thiosulfate, and the sand is medium-coarse river sand with a particle size of approximately 0.75mm.

[0031] The above-described embodiments of the construction method for medium and small square reserved openings in a radiation protection structure of the present invention do not constitute a limitation on the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A construction method for medium and small square reserved openings within a radiation protection structure, characterized in that, Includes the following steps: Step 1: Measure the dimensions of the square opening, and process the mold box using a steel plate according to the opening dimensions. The inner diameter of the iron box is slightly larger than the opening dimensions. Step 2: Arrange longitudinal and transverse reinforcing ribs on the outer surface of the iron box, and spot weld the reinforcing ribs together. The distance between the transverse and / or longitudinal reinforcing ribs and the iron box spot welds shall not be greater than 10cm. Step 3: When the side cross-sectional dimension of the square opening is greater than 600mm, add an internal support in the middle of the square opening and fix it with light spot welding; Step 4: Before installing the metal box, seal both ends with multiple plastic bags; Step 5: Install a trapezoidal support frame at the lower part of the pre-embedded design position of the iron box, fix the iron box to the trapezoidal support frame, and then arrange horizontal and vertical opening reinforcements in the structural reinforcement around the iron box to constrain the longitudinal and lateral displacement of the opening. Step 6: At the same time, install a steel wire mesh at a height of 50cm above the iron box to reduce the direct impact of concrete. Step 7: When pouring concrete, control the pouring height to not exceed 3 meters. When the concrete falls, it is strictly forbidden to directly impact the pipe. When vibrating the concrete, keep the vibrator 10cm away from the iron box. Step 8: After the radiation shielding structure is cast and formed, insert the equipment first. After the equipment is debugged, seal the gap between the equipment and the iron box with barite mortar, leaving grouting ports and overflow ports. Then inject cement grout. After grouting is completed, add lead plates to the surface for radiation shielding reinforcement, extending 10cm on both the equipment and structure surfaces.

2. The construction method for medium and small square reserved openings within the radiation protection structure according to claim 1, characterized in that, In step 1, the mold box is made of 3mm steel plate, and the inner diameter of the box is slightly larger than the opening size by 2cm.

3. The construction method for medium and small square reserved openings within the radiation protection structure according to claim 1, characterized in that, In step 2, both the longitudinal reinforcing ribs and the transverse reinforcing ribs are made of Φ16 steel bars with a spacing of 400mm.

4. The construction method for medium and small square reserved openings within the radiation protection structure according to claim 1, characterized in that, In step 3, the spacing between adjacent inner supports is 400mm.

5. The construction method for medium and small square reserved openings within the radiation protection structure according to claim 1, characterized in that, In step 5, the trapezoidal support frame is a frame structure welded from support uprights, support longitudinal bars, and support horizontal bars, and the distance between two adjacent support uprights is no more than 600mm.

6. The construction method for medium and small square reserved openings within a radiation-proof structure according to claim 1 or 5, characterized in that, The support frame is welded from Φ18 steel bars.

7. The construction method for medium and small square reserved openings within a radiation-proof structure according to claim 1, characterized in that, In step 6, the steel wire barrier is made of a Φ14 steel bar skeleton and a 4mm steel wire mesh.

8. The construction method for medium and small square reserved openings within the radiation protection structure according to claim 1, characterized in that, In step 8, the lead plate is 20cm wide and 10mm thick.

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