Large open caisson one-time sinking construction method

Abstract

The invention discloses a one-time sinking construction method for a large open caisson. The one-time sinking construction method comprises the following steps: constructing a cushion layer and building a brick blank film; manufacturing the open caisson section by section; breaking and removing a cushion layer and a brick blank film; excavating and sinking by a small excavator; the crawler-type grab bucket excavates soil and sinks; the telescopic boom excavator excavates soil and sinks; sucking sludge by air and sinking; and the open caisson is subjected to underwater bottom sealing. The problems that in an existing open caisson construction mode, sinking is not in place easily, and the deviation exceeds the allowable deviation after the open caisson is subjected to final sinking are solved.

Description

Technical Field

[0001] The invention relates to the technical field of building construction, and in particular to a one-time sinking construction method for a large caisson. Background Art

[0002] At present, the caisson construction methods in the construction process are generally divided into two types: multiple production and one sinking method and multiple production and multiple sinking method. Compared with the multiple production and multiple sinking method, the multiple production and one sinking method can use the concrete curing time to make the next section of the caisson wall, while avoiding the problem of repeatedly setting up and dismantling scaffolding during multiple production and multiple sinking, saving construction time and cost.

[0003] During the sinking process of the caisson, sudden sinking, over-sinking, tilting, incomplete sinking, etc. may occur due to the influence of geological conditions, which may lead to extended construction period. Summary of the invention

[0004] In order to overcome the defects of the prior art, a large caisson one-time sinking construction method is provided to solve the problem that the existing caisson construction method is prone to not sinking into place and the caisson exceeds the allowable deviation after final sinking.

[0005] In order to achieve the above object, a large caisson one-time sinking construction method is provided, comprising:

[0006] Constructing a cushion layer 1 on the ground, and constructing a brick membrane on the cushion layer;

[0007] An outer scaffold and an inner scaffold are respectively set up on opposite sides of the cushion layer;

[0008] Installing the template of the first caisson section between the outer scaffolding and the inner scaffolding;

[0009] Pouring concrete in the template to form the first caisson section;

[0010] Casting a large caisson section by section from bottom to top and removing the outer scaffold and the inner scaffold so that the brick membrane is supported on the blade foot of the large caisson;

[0011] Using a small excavator with a crushing head to break the cushion layer and the brick membrane in the large caisson and remove them from the large caisson through the hopper of the crawler crane;

[0012] Before the large caisson sinks to the groundwater level, a small excavator is used to dig and remove soil in the large caisson;

[0013] After the large caisson sinks to the groundwater level, in the loose stratum, using a crawler-type grab bucket outside the large caisson to symmetrically dig and remove soil in the large caisson;

[0014] After the large caisson sinks to the groundwater level, a telescopic arm excavator is used to dig and remove soil in the large caisson;

[0015] When the large caisson is sunk to the designed elevation, air suction is used to symmetrically suck soil in the large caisson;

[0016] After the large caisson sinks to the designed elevation, underwater concrete pouring is used to seal the bottom of the large caisson.

[0017] Furthermore, the cushion layer is a plain concrete cushion layer.

[0018] Furthermore, a sand cushion layer is provided under the plain concrete cushion layer.

[0019] Furthermore, the symmetrical excavation is symmetrical excavation from inside to outside with the plane center of the large caisson as the center.

[0020] The beneficial effect of the present invention is that the large-scale caisson one-time sinking construction method of the present invention is suitable for the large-scale caisson undrained sinking construction of the multiple-time sinking method. Multiple-time sinking can utilize the concrete curing time to produce the wall of the next section of the caisson, while avoiding the problem of repeatedly setting up and dismantling scaffolding when making multiple sinkings, saving construction time and cost. According to the geological conditions, a multi-machine combination excavation sinking or air suction mud sinking is used instead of ordinary mechanical excavation sinking. Under the premise of speeding up the construction progress, it is guaranteed to meet the allowable deviation after the caisson is finally sunk, including the average elevation of the blade foot, the displacement of the center line of the blade foot, and the height difference between any two feet in the four corners, thereby improving the quality of the caisson sinking construction. The large-scale caisson one-time sinking construction method of the present invention is faster and more efficient in the large-scale caisson undrained sinking construction process of the multiple-time sinking method, and guarantees the quality of the caisson sinking construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0022] Figure 1 It is a structural schematic diagram of a large caisson one-time sinking construction method according to an embodiment of the present invention.

[0023] Figures 2 to 12 It is a schematic diagram of the steps of a one-time sinking construction method for a large caisson according to an embodiment of the present invention.

[0024] Fig.13 It is a schematic diagram of symmetrical excavation according to an embodiment of the present invention.

[0025] Fig.14 This is a schematic diagram of the layout of a construction platform according to an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant inventions, rather than to limit the inventions. It should also be noted that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0027] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0028] Reference Figures 1 to 14 As shown, the present invention provides a large caisson one-time sinking construction method, comprising the following steps:

[0029] S1. construct a cushion layer 1 on the ground, and construct a brick membrane 4 on the cushion layer 1.

[0030] See also Figure 2 As shown, the cushion layer 1 is a plain concrete cushion layer. A sand cushion layer 11 is provided below the plain concrete cushion layer.

[0031] S2. An outer scaffold 2 and an inner scaffold 3 are respectively set up on opposite sides of the cushion layer.

[0032] In this embodiment, a sand cushion layer and a plain concrete cushion layer are arranged below the large caisson, and a basic plain concrete cushion layer is arranged below the working scaffold. The thickness of the caisson sand cushion layer is calculated according to the weight of the caisson and the bearing capacity of the foundation soil, and the width of the caisson sand cushion layer and the thickness and width of the caisson plain concrete cushion layer are determined.

[0033] The sand cushion layer is arranged in the form of full-floor paving. When the plane size of the caisson is large, it is arranged in the form of ring-wall paving. Medium sand and coarse sand with good particle grading are used for layered compaction.

[0034] The plain concrete cushion layer of the caisson, the plain concrete cushion layer of the working scaffolding foundation inside the caisson, and the plain concrete cushion layer of the working scaffolding foundation outside the caisson are separated by wooden formwork and poured with plain concrete.

[0035] The brick membrane is laid under the blade foot of the large caisson, and holes for fixing the caisson template are reserved on it.

[0036] S3. See Figure 3 As shown, the template of the first caisson section 51 is installed between the outer scaffolding and the inner scaffolding.

[0037] S4. Continue reading Figure 3 As shown, concrete is poured into the formwork to form the first caisson section 51.

[0038] S5. See Figure 4 and Figure 5As shown, a large caisson is formed by pouring sections from bottom to top and removing the external scaffolding and internal scaffolding, so that the brick membrane is supported on the blade foot of the large caisson.

[0039] Specifically, in this embodiment, the specific construction process of the caisson segment production of a large caisson is as follows:

[0040] The first caisson section 51 internal and external working scaffolding was set up;

[0041] The first caisson was made in 51 sections;

[0042] The inner and outer working scaffolding of the second section caisson 52 is set up;

[0043] Section 2 Caisson Production;

[0044] Section 3: Erection of scaffolding for working inside and outside caisson 53;

[0045] Section 3 Caisson Production;

[0046] The scaffolding inside and outside the caisson is removed.

[0047] S6. Use a small excavator 6 with a crushing head to break the cushion layer and brick membrane in the large caisson and remove them from the large caisson through the hopper of the crawler crane 7.

[0048] See also Figure 6 , Figure 7 As shown, the cushion layer and brick membrane are broken and cleared out, and a small excavator with a crushing head is used to symmetrically break the cushion layer and brick membrane in the caisson. The small excavator cleans the materials into the hopper in the caisson, and the crawler crane clears the materials out of the hopper and piles them outside the caisson. The excavator is used to load them into a dump truck, which is then transported to the waste dump for disposal.

[0049] S7. Before the large caisson sinks to the groundwater level, a small excavator 6 is used to dig and remove the soil in the large caisson.

[0050] See also Figure 8 , a small excavator digs the soil and sinks it. Before the caisson sinks below the groundwater level, a small excavator is used to symmetrically dig the soil in the caisson and clean it into the hopper. The crawler crane lifts the hopper and clears it out of the caisson for centralized stacking. The excavator is used to load it into a dump truck, which is then transported to the waste dump for disposal.

[0051] S8. After the large caisson sinks to the groundwater level, the crawler grab 8 outside the large caisson is used to symmetrically dig and remove the soil in the large caisson.

[0052] See also Fig. 9The crawler grab bucket digs the soil and sinks it. After the caisson sinks to the groundwater level and is located in a loose stratum, the crawler grab bucket is used to symmetrically dig the soil outside the caisson, and the soil is cleared and piled outside the caisson. The soil is loaded onto a dump truck by an excavator and transported to the dump site for disposal.

[0053] S9. After the large caisson sinks to the groundwater level, a telescopic arm excavator 9 is used to dig and remove soil in the large caisson.

[0054] See also Fig.10 The telescopic arm excavator digs the soil and sinks. After the caisson sinks to the groundwater level and is located in a dense stratum, the telescopic arm excavator is used to dig the soil symmetrically outside the caisson, and the soil is cleared and piled outside the caisson. The excavator is used to load the soil onto a dump truck, which is then transported to the dump site for disposal.

[0055] S10. When a large caisson is sunk to the designed elevation, air suction is used to symmetrically suck soil inside the caisson.

[0056] like Fig.11 As shown, the air sucks the mud down. When the caisson is about to sink to the bottom of the well, in order to avoid damage to the bored piles in the well, a water reservoir 17, a high-pressure water pump 18, a water supply pipe 19, a high-pressure water gun 20, a mud pump 21, a mud outlet pipe 22, and a mud sedimentation tank 23 are used to form a circulating flushing and suction system to symmetrically absorb the soil. The mud and sand deposited in the mud sedimentation tank need to be cleaned regularly, loaded into a dump truck by an excavator, and transported to a dump site for disposal by the dump truck.

[0057] As a preferred implementation method, the symmetrical excavation is symmetrical excavation from the inside to the outside with the plane center of the large caisson as the center.

[0058] Combination Fig.13 As shown, in the digging and sinking of small excavators, crawler grab buckets, telescopic arm excavators, and air suction mud sinking, Fig.13 Proceed in sequence, taking soil symmetrically from the center to the surrounding areas, that is, in the order of abcd, ABCD, to form the bottom of the pot and sink evenly.

[0059] Steel plates are laid at the bottom of crawler grab buckets and telescopic arm excavators to expand the supporting surface and reduce the impact on the foundation pit during construction.

[0060] The caisson is sunk without drainage and the water level in the caisson is not less than 0.5m higher than the groundwater level.

[0061] S11. After the large caisson sinks to the designed elevation, the bottom of the large caisson is sealed by underwater pouring of concrete.

[0062] The underwater bottom sealing of large caissons shall be carried out after the large caissons sink to the designed elevation and then observed for 6 to 8 hours. If the cumulative sinking amount of the caisson is not more than 10mm, the underwater concrete bottom sealing shall be carried out.

[0063] See also Fig.12 As shown, the underwater concrete bottom seal uses C30 commercial concrete, which is transported to the construction site by a concrete transport truck and pumped to the hopper by a concrete pump truck. The underwater concrete is poured bin by bin through the conduit, and the double-jointed I-beam construction platform and concrete pouring frame assist in the operation. For the layout of the construction platform, please refer to Fig.14 shown.

[0064] The large-scale caisson one-time sinking construction method of the present invention is suitable for the large-scale caisson undrained sinking construction of the multiple-time sinking method. Multiple-time sinking can utilize the concrete curing time to produce the wall of the next section of the caisson, while avoiding the problem of repeatedly setting up and dismantling scaffolding during multiple-time sinking, saving construction time and cost. According to the geological conditions, multiple mechanical combined excavation and sinking or air suction mud sinking is used instead of ordinary mechanical excavation and sinking. Under the premise of speeding up the construction progress, it is ensured that the allowable deviation after the caisson is finally sunk is met, including the average elevation of the blade foot, the displacement of the center line of the blade foot, and the height difference between any two feet in the four corners, thereby improving the quality of the caisson sinking construction. The large-scale caisson one-time sinking construction method of the present invention is faster and more efficient in the large-scale caisson undrained sinking construction process of the multiple-time sinking method, and ensures the quality of the caisson sinking construction.

[0065] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with the technical features with similar functions disclosed in this application (but not limited to) by each other.

Claims

1. A large caisson one-time sinking construction method, characterized in that: The following steps are involved: Constructing a cushion layer on the ground, and constructing a brick membrane on the cushion layer; An outer scaffold and an inner scaffold are respectively set up on opposite sides of the cushion layer; Installing the template of the first caisson section between the outer scaffolding and the inner scaffolding; Pouring concrete in the template to form the first caisson section; Casting a large caisson section by section from bottom to top and removing the outer scaffold and the inner scaffold so that the brick membrane is supported on the blade foot of the large caisson; Using a small excavator with a crushing head to break the cushion layer and the brick membrane in the large caisson and remove them from the large caisson through the hopper of the crawler crane; Before the large caisson sinks to the groundwater level, a small excavator is used to dig and remove soil in the large caisson; After the large caisson sinks to the groundwater level, in the loose stratum, using a crawler-type grab bucket outside the large caisson to symmetrically dig and remove soil in the large caisson; After the large caisson sinks to the groundwater level, in the compact stratum, a telescopic arm excavator is used to dig and remove soil in the large caisson; When the large caisson is sunk to the designed elevation, air suction is used to symmetrically suck soil in the large caisson; After the large caisson sinks to the designed elevation, underwater concrete pouring is used to seal the bottom of the large caisson.

2. The large caisson one-time sinking construction method according to claim 1 is characterized in that: The cushion layer is a plain concrete cushion layer.

3. The large caisson one-time sinking construction method according to claim 2 is characterized in that: A sand cushion layer is provided under the plain concrete cushion layer.

4. The large caisson one-time sinking construction method according to claim 1 is characterized in that: The symmetrical excavation is symmetrical excavation from inside to outside with the plane center of the large caisson as the center.

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