A reinforcement structure for waterproof board seepage and deformation in the basement

Abstract

The present invention belongs to the technical field of building construction, and relates to a reinforcement structure for the water seepage and deformation of a basement waterproof board, including: prestressed anchor rods, non-prestressed anchor rods, steel anchor plates, and steel strips. By arranging a plurality of prestressed anchor rods and non-prestressed anchor rods vertically and horizontally in a staggered manner in the water seepage and deformation area, the prestressed anchor rods are used to completely restore the deformed original waterproof board and then the non-prestressed anchor rods are used for fixing and maintaining. Then, the steel strips are used to strengthen the fixing and maintaining effect. Finally, a fine aggregate concrete protective layer and leveling layer are covered on the anchor rods and the steel strips; the structure of the present invention can reinforce the water seepage and deformation of the waterproof board more quickly and efficiently, and the repair quality is durable and effective.

Description

Technical Field

[0001] The invention belongs to the technical field of building construction, and relates to a reinforcement structure for water seepage and deformation of a basement waterproof board. Background Art

[0002] In the prior art, when the basement of a building is affected by dampness and water seepage, and warping, deformation cracking, water seepage and leakage occur locally or even entirely on the floor and the waterproof board, seriously affecting the safe use of the building, the commonly adopted method is to clean the water seepage and leakage parts and then re-lay and construct. The engineering quantity is large and the treatment effect is not good. Especially for public buildings in use, it is obviously unacceptable to the user to stop using them for a long time for construction.

[0003] Therefore, there is a need for a faster, more efficient and quality-guaranteed method for treating water seepage and leakage of the basement waterproof board to solve this building construction problem. Summary of the Invention

[0004] The technical solution adopted by the invention to solve the technical problem is: a reinforcement structure for water seepage and deformation of a basement waterproof board, comprising: prestressed anchor rods, non-prestressed anchor rods, steel anchor plates, and steel strips. The prestressed anchor rods and non-prestressed anchor rods are reinforced concrete anchor rods. The lower parts of the prestressed anchor rods and non-prestressed anchor rods are vertically grouted and anchored in the subgrade layer with qualified engineering properties. The upper ends of the prestressed anchor rods and non-prestressed anchor rods extend out of the top surface of the original waterproof board. The steel anchor plate is a steel plate with a square outer contour and a circular hole inside. The circular hole of the steel anchor plate is sleeved on the upper ends of the prestressed anchor rods and non-prestressed anchor rods. After the steel anchor plate is pressed by prestress to completely restore the deformation of the original waterproof board to be flat, the upper ends of the prestressed anchor rods and non-prestressed anchor rods are bent and welded to fixedly connect to the upper surface of the steel anchor plate, so that the prestressed anchor rods and non-prestressed anchor rods tension and lock the steel anchor plate to prevent the original waterproof board from deforming again. The subgrade layer with qualified engineering properties refers to the subgrade layer with good engineering properties that can provide sufficient anchorage for the anchor rods;

[0005] The prestressed anchor rods and non-prestressed anchor rods are arranged longitudinally and transversely in the deformed area of the original waterproof board. The prestressed anchor rods and non-prestressed anchor rods are arranged at intervals and staggered. The outermost circle of anchor rods in the deformed area of the original waterproof board are all non-prestressed anchor rods; The steel strips are respectively welded longitudinally and transversely to connect the steel anchor plates locked by adjacent two anchor rods, and then all the steel anchor plates in the deformed area of the original waterproof board are connected into a whole;

[0006] Epoxy resin flexible grouting liquid is grouted into the local cracks and fissures in the deformed area of the original waterproof board; A fine aggregate concrete protective layer and leveling layer are laid on the upper surface of the deformed area of the original waterproof board, and the fine aggregate concrete protective layer and leveling layer completely cover the anchor rod steel bars, steel anchor plates and steel strips.

[0007] Preferably, the inner steel bar of the prestressed anchor rod is a single steel bar. The upper end of the inner steel bar of the prestressed anchor rod is provided with a thread, and a nut anchor is equipped on the thread; through the threaded fit of the nut, the steel anchor plate can be pressed tightly to restore the original waterproof board around the prestressed anchor rod to be flat.

[0008] Preferably, the inner steel bar of the non-prestressed anchor rod is a bundle of 2 to 4 steel bars spot-welded together. After the steel anchor plate is sleeved on the upper end of the inner steel bar of the non-prestressed anchor rod and is pressed by prestress to completely restore the deformation of the original waterproof board to be flat, the 2 to 4 steel bars at the upper end of the inner steel bar of the non-prestressed anchor rod are evenly bifurcated and then bent and welded to connect the steel anchor plate; through the non-prestressed anchor rod, the restored and flat original waterproof board with water seepage deformation is maintained and strengthened so that it will no longer deform.

[0009] More preferably, the inner steel bar of the non-prestressed anchor rod is a bundle of 2 steel bars spot-welded together.

[0010] Preferably, the concrete grouting of the prestressed anchor rod and the non-prestressed anchor rod is two-stage grouting. The height of the first grouting in the two-stage grouting is the height of the original plain concrete cushion at the bottom of the original waterproof board, and the height of the second grouting in the two-stage grouting is lower than the upper surface height of the original waterproof board; the first grouting provides tensile adhesion for prestressed anchoring, and the second grouting provides support for restoring the original waterproof board to be flat and plugs the anchor rod holes.

[0011] More preferably, the length of the first grouting part of the prestressed anchor rod and the non-prestressed anchor rod is not less than 30-45 times the diameter of the anchor rod hole; to ensure sufficient anchor rod tension.

[0012] Preferably, before the steel strip is longitudinally and transversely welded to connect adjacent two anchor rods, an A-level structural adhesive is applied between the bottom of the steel strip and the upper surface of the original waterproof board.

[0013] More preferably, before the steel strip is longitudinally and transversely welded to connect adjacent two anchor rods, the bottoms of all the steel strips are pasted to the upper surface of the original waterproof board.

[0014] Preferably, a polymer cement-based waterproof layer is also provided between the bottom surface of the fine aggregate concrete protective layer and leveling layer and the upper surface of the original waterproof board.

[0015] More preferably, a moisture-proof layer and coating isolation layer are also provided between the bottom surface of the fine aggregate concrete protective layer and leveling layer and the polymer cement-based waterproof layer.

[0016] The beneficial effects of the present invention are:

[0017] In the present invention, a plurality of prestressed anchor rods and non-prestressed anchor rods are evenly distributed vertically and horizontally in the seepage deformation area. The prestressed anchor rods are used to completely restore the deformed original waterproof board, and then the non-prestressed anchor rods are used for fixation and maintenance. Then, the fixing effect is strengthened by steel strip, and finally, a fine aggregate concrete protective layer and leveling layer are covered on the anchor rods and steel strips. The structure of the present invention strengthens the waterproof board, making the seepage deformation faster, more efficient, and the repair quality durable and effective. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic plan view of the arrangement of anchor rods for a basement waterproof board seepage deformation reinforcement structure;

[0019] Figure 2 is a schematic diagram of a prestressed anchor rod;

[0020] Figure 3 is a schematic diagram of a non-prestressed anchor rod;

[0021] Figure 4 is a schematic plan view of the steel strip reinforcement arrangement;

[0022] Figure 5 is a schematic diagram of the bending and welding of the steel bars of the non-prestressed anchor rod;

[0023] Figure 6 is a schematic diagram of the waterproof reinforcement and repair;

[0024] In the figure, 1, prestressed anchor rod; 2, non-prestressed anchor rod; 3, steel anchor plate; 4, steel strip; 5, original waterproof board; 6, fine aggregate concrete protective layer and leveling layer; 7, polymer cement-based waterproof layer. SPECIFIC EMBODIMENTS

[0025] Next, the relevant technologies in the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0026] Reference Figures 1 to 6, A waterproof board seepage and deformation reinforcement structure for a basement, comprising: prestressed anchor rods 1, non-prestressed anchor rods 2, steel anchor plates 3, and steel strips 4. The prestressed anchor rods 1 and non-prestressed anchor rods 2 are reinforced concrete anchor rods. The lower parts of the prestressed anchor rods 1 and non-prestressed anchor rods 2 are vertically grouted and anchored in the subgrade layer with qualified engineering properties. The upper ends of the steel bars of the prestressed anchor rods 1 and non-prestressed anchor rods 2 protrude from the top surface of the original waterproof board 5. The steel anchor plate 3 is a steel plate with a square outer contour and a round hole inside. The round hole of the steel anchor plate 3 is sleeved on the heads of the upper ends of the steel bars of the prestressed anchor rods 1 and non-prestressed anchor rods 2. After the steel anchor plate 3 is pressed by prestress to flatten the original waterproof board 5 so that the deformation of the original waterproof board 5 is completely restored to a flat state, the upper ends of the steel bars of the prestressed anchor rods 1 and non-prestressed anchor rods 2 are bent and welded to fixedly connect to the upper surface of the steel anchor plate 3, so that the prestressed anchor rods 1 and non-prestressed anchor rods 2 tension and lock the steel anchor plate 3 to prevent the original waterproof board 5 from deforming again. The subgrade layer with qualified engineering properties refers to a subgrade layer with good engineering properties that can provide sufficient anchorage for the anchor rods;

[0027] The prestressed anchor rods 1 and non-prestressed anchor rods 2 are arranged vertically and horizontally in the deformation area of the original waterproof board 5. The prestressed anchor rods 1 and non-prestressed anchor rods 2 are arranged at intervals and staggered. The outermost circle of anchor rods in the deformation area of the original waterproof board 5 are all non-prestressed anchor rods 2; The steel strips 4 are respectively welded vertically and horizontally to connect the steel anchor plates 3 locked by adjacent two anchor rods, and then all the steel anchor plates 3 in the deformation area of the original waterproof board 5 are connected into a whole;

[0028] Epoxy resin flexible grouting liquid is grouted into the local cracks and fissures in the deformation area of the original waterproof board 5; A fine aggregate concrete protective layer and leveling layer 6 is laid on the upper surface of the deformation area of the original waterproof board 5, and the fine aggregate concrete protective layer and leveling layer 6 completely cover the anchor bar steel heads, steel anchor plates 3 and steel strips 4.

[0029] Further, the inner steel bar of the prestressed anchor rod 1 is a single steel bar, and the upper end of the inner steel bar of the prestressed anchor rod 1 is provided with a thread, and a nut anchor is equipped on the thread; Through the threaded cooperation of the nut, the steel anchor plate 3 can be pressed to restore the original waterproof board 5 around the prestressed anchor rod 1 to a flat state.

[0030] Further, the inner steel bar of the non-prestressed anchor rod 2 is 2 to 4 steel bars spot-welded into a bundle. After the steel anchor plate 3 is sleeved on the upper end of the inner steel bar of the non-prestressed anchor rod 2 and is pressed by prestress to flatten the original waterproof board 5 so that the deformation of the original waterproof board 5 is completely restored to a flat state, the 2 to 4 steel bars at the upper end of the inner steel bar of the non-prestressed anchor rod 2 are evenly bifurcated and then bent and welded to connect to the steel anchor plate 3; The restored flat seepage and deformed original waterproof board 5 is maintained and reinforced by the non-prestressed anchor rod 2 so that it no longer deforms.

[0031] Furthermore, the inner steel bar of the non-prestressed anchor rod 2 is 2 steel bars spot-welded into a bundle.

[0032] Further, the concrete grouting of the prestressed anchor rod 1 and the non-prestressed anchor rod 2 is carried out in two stages. The height of the first-stage grouting for both is the height of the original plain concrete cushion plate at the bottom of the original waterproof board 5, and the height of the second-stage grouting for both is lower than the upper surface height of the original waterproof board 5. The first-stage grouting provides tensile attachment for prestressed anchoring, and the second-stage grouting provides support for restoring the flatness of the original waterproof board 5 and seals the anchor holes.

[0033] Furthermore, the length of the first-stage grouting part of the prestressed anchor rod 1 and the non-prestressed anchor rod 2 is not less than 30 - 45 times the diameter of the anchor hole; this ensures sufficient anchor tension.

[0034] Further, before the steel strip 4 is longitudinally and transversely welded to connect adjacent two anchor rods, an A-level structural adhesive is applied between the bottom of the steel strip 4 and the upper surface of the original waterproof board 5.

[0035] Furthermore, before the steel strip 4 is longitudinally and transversely welded to connect adjacent two anchor rods, the bottom of all the steel strips 4 is completely pasted to the upper surface of the original waterproof board 5.

[0036] Further, a polymer cement-based waterproof layer 7 is also provided between the bottom surface of the fine aggregate concrete protective layer and leveling layer 6 and the upper surface of the original waterproof board 5.

[0037] Furthermore, a moisture-proof layer and coating isolation layer are also provided between the bottom surface of the fine aggregate concrete protective layer and leveling layer 6 and the polymer cement-based waterproof layer 7.

[0038] Embodiment

[0039] This embodiment is an art museum in a certain city. The total building area is 5500 ㎡, including 2553 ㎡ on three above-ground floors and 2947 ㎡ on one basement floor with a partial second basement floor. The main functions of the basement floor and its mezzanine of the art museum are equipment rooms, temporary exhibition halls, multimedia demonstration halls, multi-functional lecture halls, restoration rooms, offices, collection storages, etc.; the main function of the first above-ground floor is an exhibition hall, and auxiliary rooms such as duty rooms, reception rooms, and calligraphy and painting classrooms are arranged; the second floor is a calligraphy and painting exhibition hall; the third floor is a fine art exhibition hall.

[0040] The construction of this project started in June 2016 and the main body was completed in June 2017. Subsequently, it entered the installation and decoration stage. In November of the same year, the waterproof board in the basement of the art museum was unexpectedly impacted by a high water head pressure. Local warping, deformation cracking, water seepage and leakage occurred on the waterproof board of the multi-functional lecture hall at the -7.000m elevation in the basement, seriously affecting the safe use of the project. The original design for the external waterproofing of the basement was two coats of polymer cement waterproof coating.

[0041] Analysis of the reasons for water seepage. According to the geological exploration report of this project, the groundwater in the site exists at a depth of -12.0m below the ground surface. The surface layer within the project land is miscellaneous fill with a thickness of 0.5 - 1.2m, and beneath it is rock stratum, consisting of strongly weathered rock with a thickness of 1.0m - 6.0m, and beneath that is slightly weathered rock, and the thickness of the slightly weathered rock stratum has not been penetrated.

[0042] According to the ex - post investigation and analysis, the entire project is located in a hilly and mountainous slope area. From the excavation of the foundation pit in June 2016 to the completion of the construction of the entire main structure in June 2017 for the art museum, no groundwater was found. It was not until November 2017 that groundwater suddenly appeared. According to analysis, the water source may come from the mountain stream water system or may come from the leakage of the water storage tank on the high ground to the north of the project. The water head height is about 1.5m, and this water head height is basically the same as the depth of the building basement foundation buried in the strongly weathered rock stratum. Since this part of the groundwater has nowhere to seep in the rock stratum, it accumulates and generates an upward buoyancy force on the building. The magnitude of the buoyancy force is about 1.5m * 10KN / m 3 = 15KN / m 2 , which is less than the base pressure of the waterproof board of the entire building (70KN / m 2 ). It will not cause the whole building to float and is safe. However, this buoyancy force will generate a large internal force on the waterproof board of the basement, especially for the waterproof board with a large span, which will generate a large buoyancy force and internal force. This is the reason for the deformation, warping, cracking and water seepage of the waterproof board at the multi - functional lecture hall.

[0043] Reinforcement plan. After on - site investigation, accident cause analysis and inference, it is determined to carry out the following reinforcement treatment on the current situation of water seepage of the waterproof floor slab of the art museum basement, and divide it into the following steps to carry out the reinforcement and repair construction according to the process:

[0044] (1) Well point dewatering around the building;

[0045] (2) Structural reinforcement of the basement waterproof board;

[0046] (3) Leakage waterproof repair of the waterproof board;

[0047] Well point dewatering around the building; Before reinforcement, first dewater the groundwater around the four sides of the building to ensure that there is no surface water inside during the reinforcement and repair of the waterproof floor slab of the art museum basement. The dewatering adopts the well point dewatering scheme. Dewatering wells are set around the periphery of the building basement, and water pumps are used to pump water in the wells to the nearby municipal rainwater wells. For the detailed outdoor dewatering scheme and construction practices, see the construction party's plan.

[0048] Anchoring reinforcement of the basement waterproof board; Considering the engineering geology and the topographic and geomorphic characteristics of the site, the site location belongs to the transitional zone from Changbai Mountain to the Songnen Plain, belonging to the low - hilly landform. The overall terrain within the site is high in the north and low in the south, and high in the east and low in the west. This project is located at the lower position of the slope.

[0049] According to the exploration report and detection results, there are no macroscopic adverse geological effects, the site area is relatively stable, and it is suitable for engineering construction. The soil layers at the site are distributed as follows:

[0050] The first layer is miscellaneous fill: with a thickness of 0.4 - 1.4 meters and poor engineering properties;

[0051] The second layer is completely weathered granite: the core is in the shape of gravel, with a thickness of 1.4 - 6.6 meters and good engineering properties; the characteristic value of the foundation bearing capacity is 300Kpa

[0052] The third layer is strongly weathered granite: with good engineering properties, the characteristic value of the foundation bearing capacity is 600Kpa, and there is no soft layer below it. No groundwater was seen during the exploration period.

[0053] General situation of the original structure foundation; in this embodiment, the foundation burial depth is -4m to -7m, all the miscellaneous fill on the surface of the foundation has been excavated, and the base has reached the second layer of completely weathered granite layer. A natural foundation is adopted in this embodiment. The current situation of the foundation pit excavation is completely consistent with the geological exploration results.

[0054] The structural system adopts a reinforced concrete frame structure, and the foundation form adopts an independent foundation under reinforced concrete columns plus a 250mm thick concrete waterproof board scheme. A concrete strip foundation is adopted under the concrete retaining walls around.

[0055] Among them, the reinforcement of the waterproof board is Φ12@200 double-layer bidirectional, and the anti-seepage grade is P6.

[0056] Design scheme of the waterproof board anchor bolts; according to the actual situation on site, the design adopts the method of rock anchor bolts + pasted steel plates for reinforcement and repair of the waterproof board. A total of 55 anchor bolts are designed and constructed. See the following design plan of the anchor bolt layout:

[0057] Among them, there are 41 non-prestressed anchor bolts No. 2 and 14 prestressed anchor bolts No. 1. The specific layout is as Figure 1 shown. The following calculations are required to estimate the characteristic value of the tensile resistance of a single anchor bolt: (1) Calculation of the rod body strength. (2) Calculation of the shear strength between the mortar body and the rock and soil layer. (3) Calculation of the bond strength between the anchor bolt rod body and the grouting body. The minimum value of the calculation results of the above three is taken as the characteristic value of the tensile resistance of a single anchor bolt. The following is the calculation of the anchor bolts for this project:

[0058] Limited by the construction space in the basement, this embodiment plans to adopt small-diameter Φ100 anchor bolts, and the anti-floating head height is designed according to 1.5m high. The calculation of its characteristic value of the tensile resistance is as follows:

[0059] The area A of the multi-functional banquet hall is 11.67m * 17.1m = 199.6㎡, taking 200㎡

[0060] Water buoyancy: F = 200㎡ * 15KN / ㎡ * 1.2 = 3600KN

[0061] Number of anchor bolts: n = 3600 kN / 70 = 51.4 pieces, and the actual layout is n = 55 pieces

[0062] Characteristic value of tensile bearing capacity: Nak = 3600 kN / 55 pieces = 65.5 kN

[0063] According to the calculation, Nak = 70 kN is actually taken, and the reinforcing bar of the tendon body is HRB400, fy = 360 N / m²

[0064] (1) Calculation of steel bar area (in accordance with Article 8.2.2 of Technical Code for Building Slope Engineering GB50330 - 2013)

[0065] As ≥ (Kb * Nak) / fy = (2.0 * 70 * 10^3) / 360 = 380 mm²

[0066] One steel bar of 22 can be adopted, As = 380 mm²

[0067] (2) Anchorage length between the anchor bolt anchor body and the stratum (in accordance with Article 8.2.3 of Technical Code for Building Slope Engineering GB50330 - 2013)

[0068] La ≥ (K * Nak) / (π * D * frbk)

[0069] = 2.4 * 70 / (3.14 * 100 * 0.2) = 2.68 m

[0070] (3) Anchorage length between the anchor bolt steel bar and the anchoring mortar (in accordance with Article 8.2.4 of Technical Code for Building Slope Engineering GB50330 - 2013)

[0071] La ≥ (K * Nak) / (n * π * d * fb)

[0072] = 2.4 * 70 / (1 * 3.14 * 22 * 2.4) = 1.01 m

[0073] Taking the above factors into consideration, the rock - entering length of a single anchor bolt is taken as La ≥ 3.50 m

[0074] Consolidation body: In this embodiment, 30 MPa cement slurry is selected, and the strength grade meets the requirements of the design and national codes

[0075] Anchor bolts: There are two types, namely prestressed anchor bolt 1 and non - prestressed anchor bolt 2. The fully - bonded non - prestressed anchor bolt 2 adopts anchor bars of 2φ16 (HRB400), spot - welded into bundles; the total number is 41 pieces. As shown in the appendix Figure 3 As shown. The prestressed anchor bolt 1 adopts anchor bars of 1φ22 (HRB400), and the total number of anchor bolts: 14 pieces. As shown in the appendix Figure 2 As shown

[0076] All anchor rods are grouted with cement slurry. In this embodiment, 30MPa cement slurry is used, which is grouted twice. The outlet of the grouting pipe should be inserted 300-500mm from the bottom of the hole. The cement slurry is continuously grouted from bottom to top, and it is ensured that the hole is drained and exhausted smoothly. The first grouting height is to the bottom of the cushion layer of the original waterproof board 5. The prestressed anchor rod 1 is grouted once before prestressing. After the prestressing is completed, the second grouting is performed.

[0077] The plan layout and detailed drawings of anchor rods are constructed according to the requirements in the above figure. The characteristic value of the pull-out bearing capacity of the anchor rod is controlled at Nak = 70KN.

[0078] Anchor bolt construction process flow; a. Non-prestressed anchor bolt 2 construction process flow: anchor hole positioning number → drilling rig in place → drilling → anchoring → grouting and pulling out the pipe → secondary grouting → anchor sealing. b. Prestressed anchor bolt 1 construction process flow: anchor hole positioning number → drilling rig in place → drilling → anchoring → grouting and pulling out the pipe → maintenance → anchor bolt tensioning and locking → secondary grouting → anchor sealing.

[0079] Anchor construction process; 1) Anchor hole construction equipment: Drilling machine: Since the drilling construction is limited by the basement space, it is determined to use a small, portable, fully pneumatic down-the-hole hammer drill to drill holes. The hole diameter is Φ100 and the diameter is all the way to the bottom. Air compressors and other equipment are also provided. 2) Drilling layout and positioning: Determine the hole position according to the construction anchor plan layout, and make markings and pre-inspections. 3) Anchor hole: Install the anchor hole drill, level, adjust the vertical position, and stabilize it. Start the air compressor. When the air pressure reaches a certain pressure, the down-the-hole hammer forms a rotating vibration, and the drilling rig power head is started for punching and drilling. In order to prevent the hole from being biased, slow impact should be adopted when drilling; uniform and slow advance is adopted during the punching and drilling process. When encountering large resistance, the down-the-hole hammer is lifted upward, and the lifting distance is about 0.30-0.50 meters. The penetration is impacted again with the rotating vibration. After the hole is drilled to a certain depth, the drill residue is removed until the hole depth reaches the design requirement. After the hole reaches the designed depth, the bottom of the down-the-hole hammer is cleaned by air pressure for 2-3 minutes, and the sediment is removed as the drill pipe is lifted.

[0080] The anchor hole diameter is 100mm, the hole diameter deviation is no more than 2cm, the drilling depth deviation should not be less than 1% of the design depth, nor should it be greater than 500mm of the design depth, and the hole depth should meet the design requirements;

[0081] After the anchor hole is formed, the air duct connected to the air compressor is placed in the hole, and flushed repeatedly from top to bottom and then from bottom to top to ensure that there is no debris in the hole;

[0082] Manufacture and Installation of Anchor Rod Body in Hole: The non-prestressed anchor rod 2 is made of 2Φ16 (HRB400), and the main steel bars are spot-welded into bundles; the prestressed anchor rod 1 is made of 1Φ22 (HRB400). To apply prestress at the end of the prestressed tendon, threads with nuts that can be tightened are required at the upper end of the prestress, and the threads should have sufficient length to ensure that the stroke of the nut during prestress application can deform and reset the waterproof board. The thread length L≥350mm.

[0083] Primary Grouting of Anchor Rod: The grouting of the anchorage section adopts the bottom-up grouting method. The outlet of the grouting pipe should be inserted 300 - 500mm from the bottom of the hole, and the slurry should be continuously poured from bottom to top. The grouting pipe should be pulled out while grouting, and the pulling height should not exceed the slurry level in the hole until the designed height of the anchorage section, that is, the lower surface height of the plain concrete cushion under the original waterproof board 5, is reached.

[0084] Cleaning of Waterproof Board: After the primary grouting of the anchorage section in the anchor rod hole has set, start the grouting pump and use clean water to wash the slurry in the anchor rod hole and the slurry on the entire indoor waterproof board. Especially, the sediment in the hollow part under the waterproof board should be cleaned thoroughly.

[0085] Waterproof Repair of Waterproof Board: Use flexible waterproof grouting liquid such as PNC901 (a type of grouting liquid based on Penetron cement) to grout, filling the voids and cracks under the waterproof board. Conduct local waterproof repair at the bottom of the waterproof board around the anchor rod drilling.

[0086] Application of Prestress: After the mortar strength of the anchor body of the prestressed anchor rod 1 reaches 100% of the designed strength, install the steel anchor plate 3 (i.e., the bearing plate) according to the design requirements and layout of the prestressed anchor rod 1, and turn the nut to apply prestress to the free section of the tendon. According to the construction sequence starting from the anchor rod at the mid-span position of the plate and moving towards the surrounding edge anchor rods, the prestress is applied manually by tightening the nut. The prestress application should ensure that the prestress of the 14 prestressed anchor rods 1 is applied evenly and synchronously as much as possible to ensure that the deformation of the waterproof board is completely restored to flatness.

[0087] Secondary Grouting of Non-prestressed Anchor Rod 2: After the stress construction of all prestressed anchor rods 1 is completed, the secondary grouting of the non-prestressed anchor rod 2 can be carried out. The requirements for the mortar are the same as before, and the non-prestressed anchor rod 2 is sealed and the anchor bars are anchored according to the design requirements. Use epoxy resin mortar to paste the anchor plate firmly and densely at the grouting port of the anchor rod hole.

[0088] Secondary Grouting of Prestressed Anchor Rod 1: After the secondary grouting of the non-prestressed anchor rod 2 and the anchoring of the anchor bars, at this time, the non-prestressed anchor rod 2 can replace the prestressed anchor rod to apply stress to the waterproof board. The anchor fittings (anchor plate and nut) of the prestressed anchor rod 1 can be removed to release the previous prestress of the tendon. Then, grout to the top of the waterproof board, and use epoxy resin mortar to paste the anchor plate firmly and densely at the grouting port of the anchor rod hole, and then bend and weld the tendon to be integrated with the anchor plate. As Figure 5 shown.

[0089] Structural reinforcement and waterproof repair of the waterproof board: 1. Structural reinforcement of the waterproof board. The steel strip 4 (-1800*100*5) is used and arranged according to the designed dimensions. First, the waterproof board under the steel strip 4 is polished, cleaned, and leveled, and then A-level structural adhesive is applied to paste and reinforce the steel strip 4 on the waterproof board. After all the steel strips 4 are pasted, the steel strip 4 is welded to the anchor plate on the bolt to form a whole. 2. Waterproof repair of the waterproof board: For local cracks on the waterproof board, epoxy resin-based flexible grouting liquid is used for grouting repair. After the structural reinforcement of the waterproof board and the grouting repair of its cracks are completed, it is necessary to apply polymer cement-based (Penetron cement-based PNC401) waterproof coating on the surface of the waterproof board twice, with a total thickness of 1.0 mm. The height of the upper wall around is 0.5 meters. After the surface waterproof construction is completed, a 300g polypropylene fabric is used to construct a moisture-proof layer and also serve as a coating isolation layer for laying one layer. Then, a 40mm thick C25 fine aggregate concrete material is used as a protective layer and also as a leveling layer to cover the bolt steel bar heads and the steel strip 4, completing the reinforcement and waterproof repair of the waterproof board. Only then can the interior decoration surface layer be constructed on it.

[0090] The construction of this embodiment started in November 2017 and was fully completed in March 2018. It has been 5 years since the project was put into use, and there has been no more water seepage phenomenon in the basement waterproof board. For the structural reinforcement and waterproof repair of the basement waterproof board of this project, there are the following advantageous features:

[0091] 1) A small-diameter bolt system is adopted, with small stress on a single bolt, and the anti-floating stress distribution of the waterproof board is uniform.

[0092] 2) The prestressed bolt 1 and the non-prestressed bolt 2 are adopted simultaneously, and after the reinforcement effect of the prestressed bolt 1 is completed, it is converted to eliminate the prestress and become the non-prestressed bolt 2.

[0093] 3) The durability of the bolt structure is greatly improved and enhanced by adopting the secondary grouting bolt method. The adverse factor that it is difficult to protect the steel bar from corrosion and durability in the free section of the prestressed anchor bar is eliminated. The adopted bolt system not only solves the structural reinforcement of the waterproof board but also strengthens its anti-floating and anti-pulling abilities.

[0094] 4) Using the steel strip 4 pasted to reinforce the waterproof board can give full play to the respective roles of the connection between the steel strip 4 and the bolt bearing plate. The anti-floating and bending resistance of the waterproof board are both improved.

[0095] 5) For the damaged condition of the waterproof board, adopting crack grouting repair and additional waterproof coating on the waterproof board are effective waterproof measures.

[0096] In terms of construction:

[0097] 1) Considering the construction environment and space limitations, a small-sized, fully pneumatic down-the-hole hammer drilling rig is adopted for hole formation. The opening diameter is Φ100 and it goes straight to the bottom, with a hole depth of up to 4m. This equipment is convenient and flexible for construction, and its small size makes it suitable for drilling operations in various rock formations. For construction in the basement space of an existing building, the use of this equipment is both convenient and reliable.

[0098] 2) Small-diameter drilled rock bolts are evenly arranged at a spacing of 2m * 2m, which is convenient for removing sediment in the voids under the waterproof board, causes little damage to the waterproof layer under the waterproof board, and is relatively easy to repair by grouting.

[0099] 3) A polymer cement-based waterproof material is painted on the surface of the waterproof board as a whole to enhance the waterproof performance of the basement waterproof board. From the actual use for 5 years, the effect is good, and there is no more water seepage and deformation phenomenon in the basement waterproof board.

[0100] In summary, the present invention provides a reinforced structure for water seepage and deformation of a basement waterproof board. By arranging a plurality of prestressed bolts and non-prestressed bolts in a criss-cross pattern in the water seepage and deformation area, the prestressed bolts are used to completely restore the deformed original waterproof board and then the non-prestressed bolts are used for fixation and maintenance. Then, a steel strip is used to strengthen the fixation and maintenance effect. Finally, a fine aggregate concrete protective layer and leveling layer are covered on the bolts and steel strips; the structure of the present invention is more efficient and faster in reinforcing the water seepage and deformation of the waterproof board, and the repair quality is durable and effective. Therefore, the present invention has a wide range of application prospects.

[0101] It should be emphasized that the above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A waterproof board seepage deformation reinforcement structure for a basement, characterized in that, Including: Prestressed anchor rods (1), non-prestressed anchor rods (2), steel anchor plates (3), and steel strips (4). The prestressed anchor rods (1) and non-prestressed anchor rods (2) are reinforced concrete anchor rods. The lower parts of the prestressed anchor rods (1) and non-prestressed anchor rods (2) are vertically grouted and anchored in the subgrade layer with qualified engineering properties. The upper ends of the steel bars of the prestressed anchor rods (1) and non-prestressed anchor rods (2) protrude from the top surface of the original waterproof board (5). The steel anchor plate (3) is a steel plate with a square outer contour and a round hole inside. The round hole of the steel anchor plate (3) is sleeved on the heads of the upper steel bars of the prestressed anchor rods (1) and non-prestressed anchor rods (2). After the steel anchor plate (3) is pressed tightly by prestress to flatten the original waterproof board (5) so that the deformation of the original waterproof board (5) is completely restored to a flat state, the upper ends of the steel bars of the prestressed anchor rods (1) and non-prestressed anchor rods (2) are bent and welded to fixedly connect to the upper surface of the steel anchor plate (3), so that the prestressed anchor rods (1) and non-prestressed anchor rods (2) tension and lock the steel anchor plate (3) to prevent the original waterproof board (5) from deforming again; The prestressed anchor rods (1) and non-prestressed anchor rods (2) are arranged vertically and horizontally in the deformation area of the original waterproof board (5). The prestressed anchor rods (1) and non-prestressed anchor rods (2) are arranged at intervals and staggered. The outermost circle of anchor rods in the deformation area of the original waterproof board (5) are all non-prestressed anchor rods (2). The steel strips (4) are welded vertically and horizontally to connect the steel anchor plates (3) locked by adjacent two anchor rods, and then all the steel anchor plates (3) in the deformation area of the original waterproof board (5) are connected into a whole; Epoxy resin flexible grouting liquid is grouted into the local cracks and fissures in the deformation area of the original waterproof board (5). A fine aggregate concrete protective layer and leveling layer (6) are laid on the upper surface of the deformation area of the original waterproof board (5). The fine aggregate concrete protective layer and leveling layer (6) completely cover the anchor bar steel bar heads, steel anchor plates (3) and steel strips (4); The inner steel bar of the prestressed anchor rod (1) is a single steel bar, and the upper end of the inner steel bar of the prestressed anchor rod (1) is provided with threads, and nut anchors are equipped on the threads; The inner steel bars of the non-prestressed anchor rods (2) are 2 to 4 steel bars spot-welded into a bundle. After the steel anchor plate (3) is sleeved on the upper ends of the inner steel bars of the non-prestressed anchor rods (2) and is pressed tightly by prestress to flatten the original waterproof board (5) so that the deformation of the original waterproof board (5) is completely restored to a flat state, the 2 to 4 steel bars at the upper ends of the inner steel bars of the non-prestressed anchor rods (2) are evenly bifurcated, then bent and welded to connect to the steel anchor plate (3).

2. The waterproof board seepage deformation reinforcement structure for a basement according to claim 1, characterized in that, The inner steel bars of the non-prestressed anchor rods (2) are 2 steel bars spot-welded into a bundle.

3. The waterproof board seepage deformation reinforcement structure for a basement according to claim 1, characterized in that, The concrete grouting of the prestressed anchor rods (1) and non-prestressed anchor rods (2) is two-stage grouting. The height of the first-stage grouting of the two-stage grouting is the height of the original plain concrete cushion at the bottom of the original waterproof board (5), and the height of the second-stage grouting of the two-stage grouting is lower than the height of the upper surface of the original waterproof board (5).

4. The waterproof board seepage deformation reinforcement structure for a basement according to claim 3, characterized in that, The length of the first-stage grouting part of the prestressed anchor rods (1) and non-prestressed anchor rods (2) is not less than 30 - 45 times the diameter of the anchor rod hole.

5. The waterproof board seepage deformation reinforcement structure for a basement according to claim 1, characterized in that, Before the steel strip (4) is longitudinally and transversely welded to connect two adjacent anchor bolts, an A-level structural adhesive is applied between the bottom of the steel strip (4) and the upper surface of the original waterproof board (5).

6. The waterproof board seepage deformation reinforcement structure for a basement according to claim 5, characterized in that, Before the steel strip (4) is longitudinally and transversely welded to connect two adjacent anchor bolts, the bottoms of all the steel strips (4) are completely pasted to the upper surface of the original waterproof board (5).

7. The waterproof board seepage deformation reinforcement structure for a basement according to claim 1, characterized in that, A polymer cement-based waterproof layer (7) is also provided between the bottom surface of the fine aggregate concrete protective layer and leveling layer (6) and the upper surface of the original waterproof board (5).

8. The waterproof board seepage deformation reinforcement structure for a basement according to claim 7, characterized in that, A moisture-proof layer and coating isolation layer is also provided between the bottom surface of the fine aggregate concrete protective layer and leveling layer (6) and the polymer cement-based waterproof layer (7).

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