Thin-walled steel sheet dam and method of construction thereof

Abstract

A thin-walled steel plate dam and its construction method are disclosed, belonging to the field of municipal water conservancy engineering technology. The dam comprises thin-walled steel plates, columns, cables, anchors, and a hydraulic membrane. The anchors are positioned on the upstream bank slope above the check flood level. The columns are evenly distributed along the arc-shaped dam axis and are tensioned to the anchors via cables. Adjacent columns are topped with struts and scissor braces, with guy ropes connected to the top. The thin-walled steel plates are welded between the columns, forming a semi-circular columnar dam surface. The dam body is embedded in the rock wall or adjacent dam sections on both sides, and the bottom is sealed to the anti-seepage wall via a hydraulic membrane. During construction, the anchors are first fixed and the anti-seepage system is arranged. The column foundations or raft slabs are poured according to geological conditions. After installing the columns, the cables and guy ropes are tensioned, the steel plates are welded, and a protective layer and hydraulic membrane are laid. This invention features a thin and lightweight structure, strong modular assembly, material savings of 70%, a 50% reduction in construction time, excellent seismic resistance, and adaptability to complex geological conditions, making it particularly suitable for long dam projects with medium to low water heads.

Description

Technical Field

[0001] This invention belongs to the field of municipal water conservancy engineering technology, specifically relating to a thin-walled steel plate dam and its construction method. It is suitable for medium and low head dams, with a thin dam body and minimal material usage. In cases where the dam line is long, the advantages in cost and speed are particularly obvious. Background Technology

[0002] Traditional dams include gravity dams, arch dams, and steel plate dams. Each of these traditional dams has its own advantages, disadvantages, and limitations when applied to complex geological conditions. Gravity dams involve large-scale engineering projects and long construction periods; earth-rock dams are difficult to integrate with other dam types for mixed construction. Arch dams have very high requirements for topographical and geological conditions and construction technology, making their application conditions demanding. Currently, commonly used steel plate dams have a monotonous structural design, with flat water-retaining surfaces. Flat plate structures have extremely low efficiency in bearing water pressure perpendicular to the plate surface, and increasing the plate thickness significantly increases costs. Currently, they can only be used in low-head projects. Furthermore, steel plate dams also have very high requirements for foundation anti-sliding and seepage prevention performance, making foundation treatment technically difficult and costly. In existing technologies, lightweight structures are used to simplify construction, such as rubber dams and inflatable dams. However, these structures have weak erosion resistance and poor durability, making them unsuitable for the needs of permanent water conservancy projects with high water heads. It is particularly noteworthy that the seepage prevention systems of traditional dams, such as clay core walls, seepage curtains, and seepage barriers, all need to be integrated with the dam body and constructed together. This process is time-consuming and can lead to mutual interference, making subsequent maintenance and repair very difficult. Summary of the Invention

[0003] The present invention aims to provide a thin-walled steel plate dam and its construction method, which has the characteristics of modular design, strong assembly, good seismic resistance and convenient construction. It is a dam that is fast, low cost and can flexibly adapt to complex geological conditions.

[0004] A thin-walled steel plate dam is characterized by comprising a thin-walled steel plate, columns, cables, anchors, and a hydraulic membrane. The anchors are set on the upstream bank slope of the dam at a position higher than the check flood level. Columns are evenly arranged along the arc-shaped dam axis with the anchors as the center. The columns are steel trusses with continuous closed flat surfaces on both sides of their water-facing side. The columns are connected to the anchors by cables.

[0005] Between adjacent columns, the tops are connected by struts, and scissor bracing is installed on the upstream facade; guy ropes are connected to the tops of the columns in the downstream direction of the dam line.

[0006] The thin-walled steel plate is welded to the flat surface of the adjacent column at both ends. The thin-walled steel plate is rolled up, and the rolled section in the middle protrudes downstream to form an upright semi-circular column with the diameter of the distance between the sides of the adjacent column. The water-facing side of the column and the thin-walled steel plate are connected in sequence to form a water-retaining dam surface.

[0007] The columns on both sides or at the ends of the thin-walled steel plate dam are directly embedded in the rock wall or adjacent dam sections; a hydraulic membrane is laid between the lower part of the dam face and the top of the anti-seepage wall of the anti-seepage curtain, and the edges of the hydraulic membrane are sealed to the water-facing dam face and the anti-seepage wall with water-stop plates respectively; a protective layer is set under the hydraulic membrane, and hydraulic fabric is laid in steep places and fine river sand is laid in gentle places.

[0008] Furthermore, the connection point of the cable between the top of all the columns and the bottom of the columns fixed on the raft and the anchor is lower than the position of the waterstop plate on the column.

[0009] Furthermore, when the cable length is greater than four times the diameter of the thin-walled steel plate coiled section, segmented installation is adopted. The cable merges near the anchor and branches near the column, specifically:

[0010] The columns are divided into single-cable columns and double-cable columns, and the cables are divided into main cables and auxiliary cables;

[0011] At least one double-cable column should be installed at equal intervals between single-cable columns;

[0012] A main cable is installed on a single-cable column and is directly connected to the anchor. Two auxiliary cables are installed on a double-cable column. The angles between the auxiliary cables and the lines connecting the column and the anchor are equal to ensure that the resultant force of the two cables points towards the anchor.

[0013] The auxiliary cables are connected to the main cables on both sides. At each branch point of the main cable, auxiliary cables branch off to both sides at an angle equal to that of the main cable, so as to balance the tension on both sides, or to take other measures to ensure that the position of the main cable does not shift.

[0014] Furthermore, the portion of the cable located below the normal water level covers the buoy.

[0015] Furthermore, when the water depth at the location of the thin-walled steel plate dam is greater than 20m, the columns are vertical layered trusses, each layer is equipped with bracing and scissor bracing, and tie cables are placed between the middle of the column and the anchor.

[0016] Furthermore, a waterproof tie rod is used to watertightly connect the cable and the hydraulic membrane at the point where the cable penetrates the hydraulic membrane. The waterproof tie rod is a solid metal rod with its two ends connected to the cable. A water-stop ring is provided in the middle of the waterproof tie rod. A hole is made in the hydraulic membrane, and the waterproof tie rod is inserted through the hole. The outer edge of the opening in the hydraulic membrane is fixed to the water-stop ring by a flange and an integrated screw.

[0017] A method for constructing a thin-walled steel plate dam, characterized by comprising the following steps:

[0018] S1, anchorage is fixed on the rock foundation above the check flood level on the upstream bank slope of the right bank of the dam;

[0019] S2, An underground seepage prevention system is arranged upstream of the dam axis of the thin-walled steel plate dam. A reinforced concrete seepage prevention wall is set at the top of the seepage prevention system, and a seepage prevention and water-stopping joint plate is buried on the top of the wall.

[0020] S3, excavate the dam foundation, divide it into sections according to depth, and shape the cross-section into a stepped shape with vertical bank slope. In sections where the foundation is bedrock, pour concrete column foundations on the foundation, and directly pour and connect the end column with the column foundation on the bank side. In sections where the foundation is a stable sedimentary layer, carry out consolidation grouting and other strengthening treatments to improve the bearing capacity and scour resistance of the foundation surface. Pour raft slabs on the foundation as enlarged foundations for the columns. The columns are erected on the raft slabs, and limit blocks are set on both sides of the column base to restrict the rotation and displacement of the columns. The foundation between the raft slabs, located below the thin-walled steel plate, is poured with concrete to the same height as the top surface of the raft slab.

[0021] S4, Erect supports and scaffolding, and cast the columns to the column foundation or erect them on the raft slab;

[0022] S5, install struts and scissor braces, pull cables and guy ropes, cover the floating body on the cables below the normal water level, after all the cables and guy ropes are connected, tighten them gradually and symmetrically in a cycle. After the cables are tightened, weld the thin-walled steel plate to the column. The gap between the bottom of the thin-walled steel plate and the raft plate and foundation is less than 1cm. Weld the water-stop plate at the bottom of the dam surface. After completion, dismantle and remove the supports and scaffolding.

[0023] S6. A protective layer of pebbles with a particle size of 2-4cm is laid on the upstream face of the dam toe. The pavement is thickened at the corners. A hydraulic fabric is laid on the protective layer as an interlayer. Fine river sand is laid on the hydraulic fabric, and a hydraulic fabric is laid on top of the fine river sand.

[0024] S7, covering the hydraulic membrane, the hydraulic membrane is connected to the waterstop plate and waterproof tie rod for waterproofing; for the substructure, the protruding parts in contact with the hydraulic membrane are rounded or covered with a protective layer.

[0025] The beneficial effects of this invention are as follows:

[0026] (1) This invention uses thin-walled steel plates, cables, columns, etc. to construct the dam body. The load characteristics of the columns with the same diameter and depth and the combination of thin-walled steel plates are completely consistent, and the shapes and specifications are the same. The steel plate walls, segmented columns and anchor cables are highly assemblable, which is conducive to standardization, fine design and mass production, and modular construction. The dam body is thin and simple in structure, and the components are light and small, which facilitates the rapid assembly of the dam body and reduces the use of large construction machinery and equipment. Compared with traditional gravity dams, the material consumption is reduced by more than 70% and the construction period is shortened by 50%, which is especially suitable for situations where the dam line is long and there is a lack of dam construction materials.

[0027] (2) The arc-shaped dam axis and the semi-circular thin-walled steel plate form a curved flexible deformation-resistant structure. The segmented columns are erected in the sliding groove at the top of the raft slab, forming an elastic dynamic stability system with the cables, which significantly improves the seismic resistance of the traditional rigid dam.

[0028] (3) By combining the cable segmentation and merging, the cable arrangement is simplified, the amount of cable used is reduced by 30%, and the cable is horizontally positioned by the float, which effectively balances the self-weight of the cable and reduces the internal stress of the structure.

[0029] (4) Steel plate dam foundations only require load-bearing and scour resistance. The anchorages, underground seepage barriers, and steel plate dam foundations of the dam can be arranged separately, reducing the requirements for engineering geological conditions and foundation treatment at the dam site. It also facilitates parallel construction and accelerates the construction speed. The ends of steel plate dams are regular, vertical, and narrow cross-sections, which facilitates the connection between different dam sections or dam types, allowing for flexible matching and giving full play to their respective advantages to adapt to complex geological and topographical conditions. Steel plate dams are lightweight and do not require the complete removal of alluvial deposits from the riverbed, which can significantly reduce the amount of dam foundation excavation. It makes full use of the original strata and protects the geomorphological ecology. The materials can be disassembled and recycled easily, which is in line with the concept of green engineering.

[0030] The construction method described in this invention is flexible, fast, economical, environmentally friendly, and has a wide range of applications, making it of great value for promotion and application as well as social and economic benefits. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the floor plan layout for Example 2.

[0032] Figure 2 This is a partial top view of a thin-walled steel plate dam.

[0033] Figure 3 This is a schematic cross-sectional view of a thin-walled steel plate dam along the direction of water flow.

[0034] Figure 4 This is a perspective view of the upstream facade of Example 1.

[0035] Figure 5 Partial perspective view of the upstream facade.

[0036] Figure 6 A schematic diagram showing the connection between the waterproof joint plate and the waterproof tie rod.

[0037] Figure 7 This is a schematic diagram of a waterproof tie rod structure.

[0038] Among them: 1-anchor seat, 2-cable, 21-buoy, 22-guest rope, 3-column, 31-column foundation, 4-thin-walled steel plate, 5-strut, 6-raft plate, 61-limiting block, 7-hydraulic membrane, 71-waterstop plate, 72-hydraulic fabric, 8-waterproof tie rod, 81-waterstop ring, 82-integral screw, 83-flange, 9-fine river sand, 10-pebbles, 11-seepage barrier wall, 12-seepage barrier curtain, 13-seepage barrier base line, 14-concrete gravity dam, 15-spillway, 16-bedrock, 17-riverbed alluvial layer, 18-grouting consolidation body. Detailed Implementation

[0039] Example 1: A certain river is a wide and shallow river with a steep right bank and a relatively gentle left bank. The riverbed has a thick layer of sand, gravel, and pebbles, and the bedrock on both bank slopes is solid and shallow. A hybrid dam is designed and constructed, with a thin-walled steel plate dam for the main channel and concrete gravity dams for both banks. The dam is generally divided into five sections from right to left. The two middle sections, C and D, are thin-walled steel plate dams, and sections A, B, and E are concrete gravity dams. Section B is the spillway section, located on the open left bank, with a spillway. The bank slope is gentle and stable, and the water flow returns to the channel well.

[0040] A thin-walled steel plate dam includes a thin-walled steel plate 4, columns 3, cables 2 and anchors 1. The anchors 1 are set on the upstream bank slope of the right bank of the dam at a position higher than the check flood level. The columns 3 are evenly arranged along the arc-shaped dam axis with the anchors 1 as the center. The columns 3 are steel trusses, and their water-facing surface and both sides are continuous closed flat surfaces.

[0041] When column 3 is set on bedrock, column 3 is fixed on column foundation 31, and column foundation 31 is fixed on bedrock. Column foundation 31 is a reinforced concrete load-bearing anti-slide pile, which is connected to column 3 by anchor bolts or buried in one piece.

[0042] When the column 3 is set on the sand and gravel sedimentary layer, the column 3 is erected on the raft 6, and a limiting block 61 is set on the raft 6 to restrict the rotation and displacement of the column 3. The sedimentary layer below the raft 6 is subjected to consolidation grouting treatment.

[0043] The top of all columns 3 and the bottom of columns 3 erected on the raft slab 6, as well as the tie cables 2 between the middle of columns 3 and the anchor 1, are used to balance the horizontal thrust of the water carried by the columns 3.

[0044] Between adjacent columns 3, the top ends are connected by struts 5, and scissor bracing is installed on the upstream facade; guy ropes 22 are connected to the top of column 3 in the downstream direction of the dam line.

[0045] The thin-walled steel plate 4 is welded to the flat surfaces of the adjacent columns 3 at both ends. The thin-walled steel plate 4 is rolled up and protrudes downstream in the middle, forming a semi-circular vertical column surface with the diameter of the distance between the sides of the adjacent columns 3. The water-facing surfaces of the columns 3 and the thin-walled steel plate 4 are connected in sequence to form the dam surface. The columns 3 on both sides or at the ends of the dam are directly embedded in the rock wall or adjacent dam sections.

[0046] A protective layer of 2-4 cm pebbles 10 is laid at the upstream toe of the dam face, with the pebbles thickened at the corners. A hydraulic geotextile 72 is laid on the protective layer as an interlayer, and fine river sand 9 is laid on the interlayer. A hydraulic geotextile 72 cushion layer is laid on top of the fine river sand 9. Above the cushion layer, a hydraulic membrane 7 is laid between the lower part of the dam face and the top of the anti-seepage wall 11 of the anti-seepage curtain 12. The edges of the hydraulic membrane 7 are sealed to the upstream dam face and the anti-seepage wall 11 with water-stop plates 71 respectively. A hydraulic geotextile 72 cushion layer is laid between the hydraulic membrane 7 and the dam face for protection.

[0047] The connection point of the cable 2, which is connected to the bottom of the column 3, is lower than the position of the water-stop plate 71 on the column 3. The cable 2 penetrates the water-membrane using a waterproof tie rod 8 to connect the cable 2 and the water-membrane 7 in a watertight manner. The waterproof tie rod 8 is a solid metal rod with its two ends connected to the cable 2. A water-stop ring 81, which is integrated with the waterproof tie rod 8, is set in the middle of the waterproof tie rod 8. A hole is made in the water-membrane 7, and the waterproof tie rod 8 is inserted through the hole. The outer edge of the hole in the water-membrane 7 is fixed to the water-stop ring 81 by a flange 83 and an integrated screw 82.

[0048] Construct this thin-walled steel plate dam according to the following steps:

[0049] S1, anchor 1 is fixed on the rock foundation on the upstream bank slope of the right bank at the proposed dam location, above the check flood level.

[0050] S2, the underground seepage prevention base line is arranged on the upstream side of the dam axis, connecting with the seepage prevention body under the gravity dam on both banks and extending to both banks to form a continuous and closed underground seepage prevention base. The underground seepage prevention body in the foundation section of the dam body includes a seepage prevention wall 11 and a seepage prevention curtain 12. The seepage prevention wall 11 is set on the top of the seepage prevention curtain 12, and a water-stop joint plate 71 is buried on the top of the seepage prevention wall.

[0051] S3, excavation of the dam foundation, divided into sections according to depth. In the bedrock section, the cross-section is trimmed into a stepped shape with vertical bank slope. Concrete column foundations 31 are poured on the bedrock 16. The column foundations 31 are anti-slide piles with sufficient bearing capacity. The end columns 3 on the bank side are directly cast and connected to the foundation or adjacent gravity dam as one unit. In the riverbed sedimentary layer, the sand, gravel, and pebble layer with good bearing capacity is retained, and the upper layer is consolidated and reinforced with grouting to improve the bearing capacity and scour resistance of the thin-walled steel plate dam section. A raft slab 6 is poured on the grouting consolidation body 18 as an enlarged foundation for the column 3. The column 3 is erected on the raft slab 6. On the raft slab 6 on both sides of the column base, there are protruding limit blocks 61 that can restrict the rotation and displacement of the column. The column 3 is a steel truss, and its water-facing surface and both sides are continuous closed flat surfaces. The foundation between the raft slabs 6 is located below the thin-walled steel plate 4 and is poured with concrete to a height that is flush with the top surface of the raft slab 6 in order to control the gap between the thin-walled steel plate 4 and the foundation.

[0052] S4, erect supports and scaffolding, and pour and connect the column 3 to the column foundation 31 or erect it on the raft slab 6; the height of the column 3 in the D dam section is greater than 20m, and the column 3 is vertically divided into two sections. At 20m below the highest water level in the middle of the column 3, a tensioning point is added to tie the cable 2 to the anchor 1. The struts 5 and scissor braces between the columns 3 are set in two layers, with the corresponding tensioning point as the boundary.

[0053] S5, between adjacent columns 3, the top ends are connected by struts 5, and the upstream facade struts 5 are set as scissor braces; the top of the column 3 is connected to the downstream direction of the dam line with guy ropes 22; the top of all columns 3 and the bottom of the column 3 fixed on the raft slab 6 are connected to the anchor 1 with tension cables 2; the part of the tension cable 2 below the normal water level covers the floating body 21; because the length of the tension cable 2 is greater than 4 times the diameter of the thin-walled steel plate 4, the tension cable 2 is set in sections; the adjacent tension cables are merged in pairs at the end near the anchor 1, and at the position near the column 3, each cable is symmetrically divided into 3 cables, which are connected to 3 adjacent columns 3 respectively.

[0054] After all the guy ropes 2 and 22 are connected, they are gradually tightened in a symmetrical cycle. After the guy ropes are tightened, the thin-walled steel plate 4 is welded and installed. The gap between the bottom surface of the thin-walled steel plate 4 and the raft slab 6 and the foundation is controlled to be less than 1cm. The water-stop plate 71 is welded to the lower part of the water-blocking surface of the thin-walled steel plate 4. Then the support and scaffolding are disassembled and removed.

[0055] S6, lay 2-4cm pebbles 10 as a protective layer at the upstream dam toe, thicken the paving at the steps, dam toe and other corners, lay a hydraulic geotextile 72 interlayer on the pebble layer, lay a fine river sand 9 cushion layer on the interlayer layer, and lay a hydraulic geotextile 72 cushion layer on top of the fine river sand 9 cushion layer.

[0056] S7, covering the hydraulic membrane 7, the position where the cable 2 penetrates the hydraulic membrane 7 is connected to the hydraulic membrane 7 by a waterproof tie rod 8. The waterproof tie rod 8 is a solid metal rod, with its two ends connected to the cable 2 respectively. A water-stop ring 81 integrated with the waterproof tie rod 8 is set in the middle of the waterproof tie rod 8. A hole is made in the hydraulic membrane 7, and the hole is fixed to the water-stop ring 81 by a flange 83 and an integrated screw 82. The top of the downstream side wall of the seepage prevention wall 11 under the hydraulic membrane 7 is rounded and a protective layer is laid to protect the hydraulic membrane.

[0057] Example 2: Figure 1 As shown, the length of cable 2 is greater than 4 times the diameter of the coiled section of thin-walled steel plate 4. Cable 2 is segmented, merging near the anchor and branching near the column. Specifically:

[0058] The column 3 is divided into a single-cable column and a double-cable column, and the cable 2 is divided into a main cable and an auxiliary cable;

[0059] A double-cable column is installed in the middle of a single-cable column;

[0060] A main cable is installed on a single-cable column and is directly connected to the anchor. Two auxiliary cables are installed on a double-cable column. The angles between the auxiliary cables and the lines connecting the column and the anchor are equal to ensure that the resultant force of the two cables points towards the anchor.

[0061] The auxiliary cables are connected to the main cables on both sides respectively; at the bifurcation point of the main cables, auxiliary cables branch off to both sides at the same angle as the main cables, so as to balance the tension on both sides, or take other measures to ensure that the position of the main cables does not shift.

[0062] The columns 3 at both ends of the thin-walled steel plate dam are embedded in the adjacent concrete gravity dam 14. The auxiliary cables are connected to the columns 3 at the ends to play a balancing role and ensure that the position of the adjacent main cables does not shift.

[0063] The other structures and construction methods of the thin-walled steel plate dam are the same as in Example 1.

Claims

1. A thin-walled steel plate dam, characterized in that... It includes thin-walled steel plates, columns, cables, anchors and hydraulic membranes. The anchors are set on the upstream bank slope of the dam at a position higher than the check flood level. Columns are evenly arranged along the arc-shaped dam axis with the anchors as the center. The columns are steel trusses with continuous closed flat surfaces on both sides of their water-facing side. The columns are connected to the anchors by cables. Between adjacent columns, the tops are connected by struts, and scissor bracing is installed on the upstream facade; guy ropes are connected to the tops of the columns in the downstream direction of the dam line. The thin-walled steel plate is welded to the flat surface of the adjacent column at both ends. The thin-walled steel plate is rolled up, and the rolled section in the middle protrudes downstream to form an upright semi-circular column with the diameter of the distance between the sides of the adjacent column. The water-facing side of the column and the thin-walled steel plate are connected in sequence to form a water-retaining dam surface. The columns on both sides or at the ends of the dam are directly embedded into the rock wall or adjacent dam sections; a hydraulic membrane is laid between the lower part of the dam face and the top of the anti-seepage wall of the anti-seepage curtain, and the edges of the hydraulic membrane are sealed to the water-facing side of the column and the anti-seepage wall with water-stop plates respectively; a protective layer is set under the hydraulic membrane, and hydraulic fabric is laid in steep places and fine river sand is laid in gentle places.

2. A thin-walled steel plate dam as described in claim 1, characterized in that... When the column is located in bedrock, the column is fixed on the column foundation, and the column foundation is fixed on the bedrock. The column foundation is a reinforced concrete load-bearing anti-slide pile, which is connected to the column anchor bolt or embedded as a whole.

3. A thin-walled steel plate dam as described in claim 1, characterized in that... When the column is located in a stable sedimentary layer, the column is fixed on the raft slab, and a limiting block is set on the raft slab to restrict the rotation and displacement of the column. The sedimentary layer below the raft slab is subjected to consolidation grouting treatment.

4. A thin-walled steel plate dam as described in claim 2, characterized in that... All the tops of the columns and the bottoms of the columns fixed to the raft deck are connected to the anchors by tie cables. The connection point of the tie cable to the bottom of the column is lower than the position of the waterstop plate on the column.

5. A thin-walled steel plate dam as described in claim 1, characterized in that... When the length of the cable is greater than four times the diameter of the thin-walled steel plate coiled section, it is installed in segments. The cable merges near the anchor and branches near the column. Specifically: The columns are divided into single-cable columns and double-cable columns, and the cables are divided into main cables and auxiliary cables; At least one double-cable column should be installed at equal intervals between single-cable columns; A main cable is installed on a single-cable column and is directly connected to the anchor. Two auxiliary cables are installed on a double-cable column. The angles between the auxiliary cables and the lines connecting the column and the anchor are equal to ensure that the resultant force of the two cables points towards the anchor. The auxiliary cables are connected to the main cables on both sides. At each branch point of the main cable, auxiliary cables branch off to both sides at an angle equal to that of the main cable, so as to balance the tension on both sides.

6. A thin-walled steel plate dam as described in claim 1, characterized in that... The cable partially covers the buoy below the normal water level.

7. A thin-walled steel plate dam as described in claim 1, characterized in that... When the water depth at the location of the thin-walled steel plate dam is greater than 20m, the columns are vertical layered trusses, each layer is equipped with bracing and shear bracing, and tie cables are placed between the middle of the column and the anchor.

8. A thin-walled steel plate dam as described in claim 1, characterized in that... The cable penetrates the hydraulic membrane using a waterproof tie rod to connect the cable and the hydraulic membrane in a watertight manner. The waterproof tie rod is a solid metal rod with its two ends connected to the cable. A water-stop ring is integrated with the waterproof tie rod in the middle of the waterproof tie rod. A hole is made in the hydraulic membrane, and the waterproof tie rod is inserted through the hole. The outer edge of the opening in the hydraulic membrane is fixed to the water-stop ring by a flange and an integrated screw.

9. A method for constructing a thin-walled steel plate dam, characterized in that... Includes the following steps: S1, anchorage is fixed on the rock foundation above the check flood level on the upstream bank slope of the dam; S2, An underground seepage prevention system is arranged upstream of the dam axis of the thin-walled steel plate dam. A reinforced concrete seepage prevention wall is set at the top of the seepage prevention system, and a seepage prevention and water-stopping joint plate is buried on the top of the wall. S3, excavate the dam foundation, divide it into sections according to depth, and shape the cross-section into a stepped shape with vertical bank slope. In the section where the foundation is bedrock, pour concrete column foundations on the foundation, and directly pour and connect the end column with the column foundation on the bank side. In the section where the foundation is a stable sedimentary layer, perform consolidation grouting to strengthen the foundation surface and improve the bearing capacity and scour resistance. Pour raft slabs on the foundation as enlarged foundations for the columns. The columns are erected on the raft slabs, and limit blocks are set on both sides of the column base to restrict the rotation and displacement of the columns. The foundation between the raft slabs, located below the thin-walled steel plate, is poured with concrete to the same height as the top surface of the raft slab. S4, Erect supports and scaffolding, and cast the columns to the column foundation or erect them on the raft slab; S5, install struts and scissor braces, pull cables and guy ropes, cover the floating body on the cables below the normal water level, after all the cables and guy ropes are connected, tighten them gradually and symmetrically in a cycle. After the cables are tightened, weld the thin-walled steel plate to the column. The gap between the bottom of the thin-walled steel plate and the raft plate and foundation is less than 1cm. Weld the water-stop plate at the bottom of the dam surface. After completion, dismantle and remove the supports and scaffolding. S6. Lay pebbles with a particle size of 2-4cm as a protective layer on the upstream face of the dam toe. The pebbles are thickened at the corners. A hydraulic fabric is laid on the protective layer as an interlayer. Fine river sand is laid on the hydraulic fabric, and a hydraulic fabric is laid on top of the fine river sand. S7, covering the hydraulic membrane, the hydraulic membrane is connected to the waterstop plate and waterproof tie rod for waterproofing; for the substructure, the protruding parts in contact with the hydraulic membrane are rounded or covered with a protective layer.

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