Prefabricated open caisson and construction method thereof

Abstract

The invention discloses a prefabricated assembly type open caisson and a construction method thereof, and relates to the technical field of open caisson construction, the prefabricated assembly type open caisson comprises a plurality of layers of prefabricated assembly sections, every two adjacent layers of prefabricated assembly sections are in butt joint through an embedded structure, and the two layers of prefabricated assembly sections can be in butt joint and positioned rapidly through the embedded structures; a plurality of connecting holes allowing steel strands to penetrate through are formed in the prefabricated assembly sections, the connecting holes penetrate through the prefabricated assembly sections from one ends to the other ends, wire penetrating grooves are formed in the middles of the side faces of the prefabricated assembly sections, the connecting holes penetrate through the wire penetrating grooves, and the steel strands are connected through the wire penetrating grooves. The same steel strand rope penetrates through the connecting holes of the two adjacent layers of prefabricated assembly sections, enters the connecting hole from the threading groove of one layer of prefabricated assembly section, and then penetrates out of the threading groove after penetrating through the connecting hole of the adjacent prefabricated assembly section, so that connection of the two adjacent layers of prefabricated assembly sections in the vertical direction is completed; and the assembled open caisson is more stable.

Description

Technical Field

[0001] The present application relates to the technical field of caisson construction, and in particular to a prefabricated assembled caisson and a construction method thereof. Background Art

[0002] Traditional caisson construction often relies on on-site casting. This, combined with the lengthy excavation process, results in a long construction period for cast-in-place caissons. This can significantly impact urban traffic if the caisson is located on a major urban road. Caisson construction using prefabricated caisson components in a factory and then transported to the site for connection can significantly reduce on-site construction time.

[0003] Prefabricated construction technology involves transferring much of the on-site work involved in traditional construction methods to factories, where building components and accessories are processed and manufactured, transported to the construction site, and finally assembled and installed on-site using reliable connections. Prefabricated buildings are characterized by high efficiency, excellent precision, minimal labor requirements, and energy conservation and environmental protection. Applying prefabricated construction technology to caisson construction can effectively improve efficiency, reduce construction costs, and shorten the construction period. However, existing prefabricated caissons still suffer from issues such as inconvenient assembly and unstable assembly. Summary of the Invention

[0004] The present application aims to solve one of the above-mentioned technical problems in the prior art. To this end, an embodiment of the present application provides a prefabricated assembled caisson.

[0005] The embodiment of the present application also provides a construction method for a prefabricated assembled caisson.

[0006] According to an embodiment of the first aspect of the present application, a prefabricated and assembled caisson is provided, comprising several layers of prefabricated assembly segments, wherein two adjacent layers of the prefabricated assembly segments are butt-jointed together by a chimeric structure, wherein the prefabricated assembly segments are provided with a plurality of connecting holes for steel ropes to pass through, the connecting holes extending from one end of the prefabricated assembly segments to the other end, a threading groove being provided in the middle portion of the side surface of the prefabricated assembly segments, the connecting holes passing through the threading groove, the same steel rope passing through the connecting holes of the two adjacent layers of the prefabricated assembly segments, the steel rope entering the connecting hole from the threading groove of one layer of the prefabricated assembly segments, and then the steel rope passing through the connecting hole of the adjacent prefabricated assembly segments and then exiting from the threading groove.

[0007] The above-mentioned prefabricated and assembled caisson has at least the following beneficial effects: the two layers of prefabricated assembly segments can be quickly docked and positioned through the interlocking structure, and are not prone to loosening after docking. After the two adjacent layers of prefabricated assembly segments are docked, the steel rope is passed through the threading groove of one layer of prefabricated assembly segments into the connecting hole, and then the steel rope passes through the connecting hole of the adjacent prefabricated assembly segment and then out of the threading groove of the adjacent prefabricated assembly segment, thereby completing the vertical connection of the two adjacent layers of prefabricated assembly segments. The connection is convenient, and each layer of prefabricated assembly segments is connected vertically through the steel rope, which can also make the assembled caisson more stable.

[0008] According to the prefabricated and assembled caisson described in the embodiment of the first aspect of the present application, a protrusion is provided at one end of the prefabricated assembly segment, and a groove is provided at the other end of the prefabricated assembly segment, wherein the protrusion of one layer of the prefabricated assembly segment can be docked with the groove of another layer of the prefabricated assembly segment, thereby forming the mosaic structure.

[0009] According to the prefabricated assembled caisson described in the embodiment of the first aspect of the present application, a hollow hole is provided in the middle of the prefabricated assembly segment, and the raised portion and the groove portion are both provided along the edge of the hollow hole.

[0010] According to the prefabricated assembled caisson described in the embodiment of the first aspect of the present application, a first inclined surface is provided on the side of the raised portion away from the hollow hole, and a second inclined surface is provided on the groove portion that is adapted to the first inclined surface.

[0011] According to the prefabricated assembled caisson described in the embodiment of the first aspect of the present application, the prefabricated assembly segment includes two symmetrical assembly parts, and the two assembly parts are connected by a locking structure.

[0012] According to the prefabricated assembled caisson described in the embodiment of the first aspect of the present application, the locking structure includes a screw member, and a through hole for the screw to pass through is provided at the same position on the side of the two assembly parts, and the through hole of one of the assembly parts is pre-embedded with an anchor plate and a nut. One end of the screw enters the through hole of one assembly part and passes through the through hole to be connected with the nut in the through hole of the other assembly part, and the other end of the screw is locked and limited by the nut to connect the two assembly parts into one.

[0013] According to the prefabricated assembled caisson described in the embodiment of the first aspect of the present application, a hidden hole is provided at the end of the through hole of the assembly part without embedded anchor plates and nuts, and the end of the screw connecting the two assembly parts into one is located in the hidden hole.

[0014] According to the prefabricated assembled caisson described in the embodiment of the first aspect of the present application, grouting holes are provided on the side of the assembly part with pre-embedded anchor plates and nuts, and the grouting holes are used to pour cement mortar into the through hole.

[0015] According to the prefabricated assembled caisson described in the embodiment of the first aspect of the present application, a single-hole anchor is provided in the wire threading groove, and the single-hole anchor is used to lock the steel rope.

[0016] According to an embodiment of the second aspect of the present application, a construction method of a prefabricated caisson is provided, comprising the following steps: The site is leveled and positioned, and after the first layer of prefabricated assembly segments are hoisted into place, excavation is carried out to sink the prefabricated assembly segments to the designed elevation. The second layer of prefabricated assembly segments are then hoisted to connect with the first layer of prefabricated assembly segments. The two layers of prefabricated assembly segments are vertically connected by using steel ropes. Excavation is then continued to sink the prefabricated assembly segments to the designed elevation for the second time. The hoisting, connection, excavation and sinking of the prefabricated assembly segments are repeated until the caisson is sunk to the designed depth. Finally, the base layer is cleaned and the bottom is sealed.

[0017] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present application is further described below with reference to the accompanying drawings and embodiments; Figure 1 This is a schematic diagram of the connection of the prefabricated assembly segments in the embodiment of the present application. Figure 1 ; Figure 2 This is a schematic diagram of the connection of prefabricated assembly segments in the embodiment of the present application. Figure 2 ; Figure 3 This is a schematic diagram of the connection of prefabricated assembly segments in the embodiment of the present application. Figure 3 ; Figure 4 is a schematic diagram of two assembly parts connected by a locking structure in an embodiment of the present application; Figure 5 This is a schematic diagram of the fixing structure of the steel strand at the threading groove in an embodiment of the present application; Figure 6 It is a structural diagram of a prefabricated assembled caisson in an embodiment of the present application.

[0019] Figure numerals: assembly part 100, grouting hole 101, hidden hole 110, connecting hole 120, threading groove 130, protrusion 140, groove portion 150, through hole 160, screw 200, nut 211, anchor plate 212, steel strand 300, single-hole anchor 400. DETAILED DESCRIPTION

[0020] This section will describe the specific embodiments of the present application in detail. The preferred embodiments of the present application are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present application, but it cannot be understood as a limitation on the scope of protection of the present application.

[0021] In the description of this application, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on this application.

[0022] In the description of this application, "several" means one or more, "many" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The terms "first" and "second" are used solely to distinguish technical features and are not to be construed as indicating or implying relative importance, or as implicitly specifying the number or order of the technical features indicated.

[0023] In the description of this application, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in this application based on the specific content of the technical solution.

[0024] Reference Figures 1 to 3 as well as Figure 6 The prefabricated assembled caisson provided in this application includes several layers of prefabricated assembly segments, and the two adjacent layers of prefabricated assembly segments are connected together by a chimeric structure. The chimeric structure enables the two layers of prefabricated assembly segments to be quickly docked and positioned, and is not prone to loosening after docking.

[0025] The prefabricated assembly segment is provided with a plurality of connection holes 120 for the steel strands 300 to pass through. The connection holes 120 pass through from one end of the prefabricated assembly segment to the other end. A threading groove 130 is provided in the middle of the side of the prefabricated assembly segment. The connection holes 120 pass through the threading groove 130. The same steel strand 300 passes through the connection holes 120 of the adjacent two layers of prefabricated assembly segments. After the adjacent two layers of prefabricated assembly segments are docked, the steel strand 300 enters the connection hole from the threading groove 130 of the prefabricated assembly segment of one layer. 120, and then the steel strand 300 passes through the connection hole 120 of the adjacent prefabricated assembly segment and then passes through the threading groove 130 of the adjacent prefabricated assembly structure. After fixing the two ends of the steel strand 300, the connection and fixation of the two adjacent prefabricated assembly segments can be completed, thereby completing the vertical connection of the two adjacent layers of prefabricated assembly segments. The connection is convenient, and after each layer of prefabricated assembly segments is connected, the steel strand 300 is used for vertical connection, which can also make the assembled caisson more stable.

[0026] In some specific embodiments, a protrusion 140 is provided at one end of the prefabricated assembly segment, and a groove 150 is provided at the other end of the prefabricated assembly segment, wherein the protrusion 140 of one layer of prefabricated assembly segment can be docked with the groove 150 of another layer of prefabricated assembly segment to form a mosaic structure.

[0027] During the docking assembly of two adjacent layers of prefabricated assembly segments, the raised portion 140 of one layer of prefabricated assembly segments docks with the groove portion 150 of the other layer of prefabricated assembly segments to complete the positioning docking of the two adjacent layers of prefabricated assembly segments, and then the two adjacent layers of prefabricated assembly segments can be firmly locked together through the steel rope 300.

[0028] In the embodiment of the present application, the prefabricated assembly segment is a rectangular structure, a hollow hole is provided in the middle of the prefabricated assembly segment, and the protrusion 140 and the groove portion 150 are both provided along the edge of the hollow hole. Figures 1 to 3 As shown, the butt joint of adjacent prefabricated assembly segments is made more stable.

[0029] In some specific embodiments, a first inclined surface is provided on the side of the protrusion 140 away from the hollow hole, and a second inclined surface is provided on the groove portion 150 to match the first inclined surface. The first and second inclined surfaces act as guides, allowing the protrusion 140 to engage the groove portion 150 without requiring perfect alignment.

[0030] like Figure 1 As shown, the prefabricated assembly segment of the embodiment of the present application includes two symmetrical assembly parts 100, which are connected by a locking structure. Splitting the prefabricated assembly segment into two symmetrical assembly parts 100 makes production and transportation very convenient.

[0031] Among them, Figures 1 to 4 As shown, the locking structure includes a screw rod 200, and a through hole 160 for the screw rod 200 to pass through is provided at the same position on the side of the two assembly parts 100, wherein the through hole 160 of one assembly part 100 is pre-embedded with an anchor plate 212 and a nut 211, and one end of the screw rod 200 enters from the through hole 160 of one assembly part 100 and passes through the nut 211 in the through hole 160 of the other assembly part 100 to be connected, and the other end of the screw rod 200 is locked and limited by the nut 211 to connect the two assembly parts 100 as one, thereby completing the horizontal locking of the two assembly parts 100.

[0032] In some embodiments, a hidden hole 110 is provided at the end of the through hole 160 of the assembly part 100 that is not pre-embedded with the anchor plate 212 and the nut 211, and the end of the screw 200 that connects the two assembly parts 100 into one is in the hidden hole 110. In some embodiments, the anchor plate 212 is now provided in the hidden hole 110, and then the screw 200 is locked with the nut 211.

[0033] In some embodiments, a grouting hole 101 is provided on the side of the assembly 100, which is pre-embedded with the anchor plate 212 and the nut 211. The grouting hole 101 is used to pour cement mortar into the through hole 160. After the two assembly parts 100 are connected together by the locking structure, the cement mortar is poured into the through hole 160 through the grouting hole 101 to fill the gap between the screw 200 and the through hole 160, making the connection between the two assembly parts 100 more integrated.

[0034] In some embodiments, such as Figure 5 As shown, a single-hole anchor 400 is provided in the threading groove 130, and the single-hole anchor 400 is used to lock the steel strand 300. When the single-hole anchor 400 is used to limit the end of the steel strand 300, an anchor plate 212 is provided between the threading groove 130 and the single-hole anchor 400.

[0035] The embodiment of the present application also provides a construction method for a prefabricated and assembled caisson, comprising the following steps: leveling and positioning the site, hoisting the first layer of prefabricated assembly segments into place, excavating to sink the prefabricated assembly segments to the designed elevation, then hoisting the second layer of prefabricated assembly segments to dock with the first layer of prefabricated assembly segments, connecting the two layers of prefabricated assembly segments vertically by using steel ropes 300, then continuing to excavate to sink the prefabricated assembly segments to the designed elevation for the second time, repeating the hoisting, connection, excavation and sinking of the prefabricated assembly segments until the caisson is sunk to the designed depth, and finally cleaning the base layer and sealing the bottom.

[0036] According to the design requirements of the drawings and the actual situation on site, when the caisson depth exceeds 10m, the first-floor prefabricated assembly segment should be equipped with blade feet, and the sinking should be carried out using the undrainage method. The soil should be excavated using a long-arm telescopic excavator or grab.

[0037] To prevent significant displacement of the working pit during construction, the caisson foundation was reinforced with Ø600 uniaxial, bidirectional mixing piles. Three rows of Ø700@500 uniaxial, bidirectional mixing piles were arranged on the outside of the caisson sidewalls, extending to 2 meters below the blade foot. The foundation at the blade foot was pre-treated with gravel replacement and compaction to achieve a bearing capacity of 100 kPa. A 50 cm sand cushion layer was then backfilled. Finally, a 100 mm thick plain concrete layer was poured, reaching a width of 2 meters.

[0038] Before cushion construction, coordinates and benchmarks are measured and positioned according to the design drawings. Coordinate control points and temporary leveling points are also located around the caisson, outside the construction area. The established control points have an accuracy of ±1mm. Gantry piles are set around the caisson and marked with lime powder. The caisson's centerline and foundation pit outline serve as the basis for positioning during caisson hoisting and sinking.

[0039] The assembly parts 100 of the first layer of prefabricated assembly segments are hoisted into place, and the screw 200 is inserted into the through hole 160 reserved in one assembly part 100 to connect to the second assembly part 100, and is locked by the reserved nut and anchor plate 212. After the screw 200 is anchored, M5 cement mortar is poured into the through hole 160 through the grouting hole 101 to realize the horizontal connection of the caisson prefabricated assembly segments.

[0040] During the caisson heightening process, the second-layer assembly fittings 100 are hoisted near the caisson. After completing the horizontal connection of the prefabricated assembly segments using the same method as the first-layer assembly fittings 100, the entire layer of prefabricated assembly segments is hoisted above the first-layer prefabricated assembly segments, completing the caisson heightening process. Finally, a steel strand 300 is threaded through the threading slots 130 of the second-layer prefabricated assembly segments into the reserved connection holes 120, then out through the threading slots 130 of the first-layer prefabricated assembly segments. After tightening and anchoring, grouting is performed to complete the vertical connection of the adjacent first and second-layer prefabricated assembly segments. Seams between the prefabricated assembly segments are sealed with waterstop strips.

[0041] The first sinking operation. A crane grab bucket is used to excavate and sink the caisson 1 meter below the ground. The concrete blocks of the cushion layer are evenly removed around the shaft walls. Due to the high groundwater level, to prevent the caisson from floating and to account for landslides and sand flow during excavation, a non-drained sinking operation is employed. Clean water is first injected into the shaft, keeping the water level no higher than 1 meter below the ground. Using a crane, the grab bucket is then used to excavate the soil in the center of the shaft, forming a pot bottom. In sandy or gravelly soils, the caisson sinks under its own weight when the pot bottom is 1-1.5 meters below the blade foot. This pushes the soil below the blade foot toward the central pot bottom. Further soil is then grabbed from the wellbore, allowing the caisson to continue sinking. In clayey or compact soils, where the soil below the blade foot is less likely to collapse toward the center, a water jet is used to loosen the soil. An air sludge suction machine is then used to extract the sludge, which is then filtered through a grit chamber and discharged into the sewer. During the sinking process, surveyors use levels to monitor the caisson's progress and make timely corrections to ensure uniform sinking. The excavation sequence is from the inside out: first loosen the soil in the center, absorb the soil in the middle, then take and combine the soil from the surrounding inner part, and finally form a large pot bottom supported by the full blade foot, so that the caisson can sink safely. At the same time, the soil plug outside the blade foot must be strictly controlled. To ensure that the force on the caisson is even and there is no internal stress concentration, when the full support of the blade foot cannot meet the sinking requirements, it is necessary to use a shovel to dig the soil at the blade foot. When removing the soil, it should be uniform, symmetrical, and peeled off layer by layer in a step-by-step manner.

[0042] When the top surface of the second-story prefabricated assembly segment sinks to 2m above the ground, excavation and sinking are stopped. After the caisson stabilizes, the third and fourth-story prefabricated assembly segments are connected using the same method. Repeat the above steps and continue sinking using the undrained method until the top surface of the fourth-story prefabricated assembly segment sinks to 2m above the ground. Excavation and sinking are stopped. After the caisson stabilizes, the fifth and sixth-story prefabricated assembly segments are connected using the same method.

[0043] After the caisson sinks to the designed elevation, its stability is observed. When the caisson has stabilized, underwater bottom seal concrete is poured to seal the bottom. Once the underwater concrete reaches the designed strength, the water in the caisson is drained. The bottom plate reinforcement is then tied above the bottom seal, and the surface of the blade foot concrete is roughened to expose the gravel, facilitating the bonding of the blade foot concrete with the bottom plate concrete.

[0044] After the reinforcement is tied, pour the bottom slab concrete. The entire bottom surface of the caisson should be poured continuously, from the periphery to the center, and compacted with a vibrator. After the bottom slab concrete is poured, it should be cured in time to complete the construction of the rectangular multi-hole prefabricated caisson.

[0045] The embodiments of the present application are described in detail above in conjunction with the accompanying drawings, but the present application is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the technical field without departing from the purpose of the present application.

Claims

1. A prefabricated caisson, characterized by: It comprises several layers of prefabricated assembly segments, and the two adjacent layers of the prefabricated assembly segments are butt-jointed together by a chimeric structure, wherein the prefabricated assembly segments are provided with a plurality of connection holes for steel strands to pass through, and the connection holes pass through from one end of the prefabricated assembly segment to the other end, and a threading groove is provided in the middle of the side surface of the prefabricated assembly segment, and the connection holes pass through the threading groove, and the same steel strand passes through the connection holes of the two adjacent layers of the prefabricated assembly segments, and the steel strand enters the connection hole from the threading groove of one layer of the prefabricated assembly segments, and then passes through the connection hole of the adjacent prefabricated assembly segment and out of the threading groove.

2. The prefabricated caisson according to claim 1, characterized in that: A protrusion is provided at one end of the prefabricated assembly segment, and a groove is provided at the other end of the prefabricated assembly segment, wherein the protrusion of one layer of the prefabricated assembly segment can dock with the groove of another layer of the prefabricated assembly segment, thereby forming the mosaic structure.

3. The prefabricated caisson according to claim 2, characterized in that: A hollow hole is provided in the middle of the prefabricated assembly segment, and the protrusion and the groove are both provided along the edge of the hollow hole.

4. The prefabricated caisson according to claim 3, characterized in that: A first inclined surface is provided on a side of the protrusion away from the hollow hole, and a second inclined surface adapted to the first inclined surface is provided on the groove portion.

5. The prefabricated caisson according to claim 1, characterized in that: The prefabricated assembly segment includes two symmetrical assembly parts, which are connected by a locking structure.

6. The prefabricated caisson according to claim 5, characterized in that: The locking structure includes a screw member, and a through hole for the screw to pass through is provided at the same position on the side of the two assembly parts. The through hole of one of the assembly parts is pre-embedded with an anchor plate and a nut. One end of the screw enters the through hole of one assembly part and passes through the through hole to be connected to the nut in the through hole of the other assembly part. The other end of the screw is locked and limited by the nut to connect the two assembly parts into one.

7. The prefabricated caisson according to claim 6, characterized in that: A hidden hole is provided at the end of the through hole of the assembly part without pre-embedded anchor plates and nuts, and the end of the screw connecting the two assembly parts into one is located in the hidden hole.

8. The prefabricated caisson according to claim 6, characterized in that: Grouting holes are provided on the side of the assembly part in which the anchor plate and the nut are pre-embedded, and the grouting holes are used to pour cement mortar into the through hole.

9. The prefabricated caisson according to claim 1, characterized in that: A single-hole anchor is provided in the threading groove, and the single-hole anchor is used for locking the steel rope.

10. A construction method for a prefabricated caisson according to any one of claims 1 to 9, characterized in that: The steps include: The site is leveled and positioned, and after the first layer of prefabricated assembly segments are hoisted into place, excavation is carried out to sink the prefabricated assembly segments to the designed elevation. The second layer of prefabricated assembly segments are then hoisted to connect with the first layer of prefabricated assembly segments. The two layers of prefabricated assembly segments are vertically connected by using steel ropes. Excavation is then continued to sink the prefabricated assembly segments to the designed elevation for the second time. The hoisting, connection, excavation and sinking of the prefabricated assembly segments are repeated until the caisson is sunk to the designed depth. Finally, the base layer is cleaned and the bottom is sealed.

Images