A bearing capacity detection device and construction method for water steel pipe piles

Abstract

The invention belongs to the technical field of civil engineering construction, and specifically relates to a construction method of a bearing capacity detection device for a water steel pipe pile, comprising at least three buoyancy airbags uniformly arranged around the steel pipe pile, a bearing platform being arranged on the buoyancy airbag, the bearing platform being higher than the top of the steel pipe pile, a force transmission structure being arranged between the top of the steel pipe pile and the bearing platform, a dynamometer being arranged on the top of the force transmission structure, and a detection device further comprising a displacement sensor, and comparing the actual bearing capacity calculated by the value measured by the dynamometer with the theoretically calculated limit bearing capacity standard value, so as to judge whether the steel pipe pile can be safely constructed; the detection device has a simple structure, can be intuitively detected, is easy to operate in construction, and can effectively detect the actual limit lateral friction resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of civil engineering construction, and in particular relates to an above-water steel pipe pile bearing capacity detection device and a construction method. Background Art

[0002] The pile side friction is the core issue in pile foundation design. Its bearing capacity is mainly borne by the pile side friction. In existing designs, the pile side friction is calculated. However, in actual applications, due to the influence of the environment, the influence of the pile side friction is obvious, especially the side friction of offshore steel pipe piles, which is difficult to obtain from theory. If it is only calculated, it will seriously affect the bearing capacity of the steel pipe pile and make the construction safety poor. Summary of the invention

[0003] The purpose of the present invention is to provide a bearing capacity detection device and construction method for water steel pipe piles, so as to solve the problems mentioned in the prior art that steel pipe piles are affected by the environment in which they are located, especially the bearing capacity of offshore steel pipe piles is difficult to obtain from theory and the construction safety is poor.

[0004] The first technical solution adopted by the present invention is an above-water steel pipe pile bearing capacity detection device, comprising at least three buoyancy air bags evenly arranged around the steel pipe pile, a bearing platform is provided on the buoyancy air bags, a force transmission structure is provided between the top of the steel pipe pile and the bearing platform, and a dynamometer is provided on the top of the force transmission structure; the detection device also includes a displacement sensor.

[0005] By evenly installing buoyancy airbags on the bearing platform, the bearing platform can stably support the load and effectively avoid overturning of the bearing platform; the load is evenly placed above the bearing platform, and the force is transmitted to the steel pipe piles through the force transmission device to achieve the sinking of the steel pipe piles. The displacement sensor is used to observe the limit sinking displacement, and then the force meter value is observed. By comparing the value measured by the force meter with the theoretically calculated standard value of the single pile vertical limit bearing capacity, it is determined whether the steel pipe piles can be safely constructed.

[0006] Preferably, a guide structure is further provided between the steel pipe pile and the buoyancy airbag, for fixing the positions of the steel pipe pile and the buoyancy airbag relative to each other.

[0007] The setting of the guide structure places the steel pipe pile in the center of the bearing platform, so that the bearing platform can stably support the piled objects and avoid overturning.

[0008] Preferably, the guide structure includes a guide ring provided at the center of the bottom of the bearing platform, and the guide ring is sleeved on the top of the steel pipe pile.

[0009] The guide ring is one of the structural forms of the guide structure. The setting of the guide ring places the steel pipe pile in the center of the bearing platform, so that the bearing platform can stably support the piled objects and avoid overturning.

[0010] Preferably, the guide structure includes a guide frame fixedly connected to the steel pipe pile, the position and number of the guide frame correspond to the buoyancy airbags, and the guide frame is used to fix the position of the buoyancy airbags.

[0011] The guide frame is another structural form of the guide structure. The setting of the guide frame places the steel pipe pile in the center of the bearing platform, so that the bearing platform can stably support the piled objects and avoid overturning.

[0012] Preferably, the force transmission structure is a jack.

[0013] The force transmission structure has a large bearing capacity and high structural accuracy requirements. Setting the force transmission structure as multiple jacks evenly arranged can meet the detection requirements. The top of the jack is connected to a dynamometer, which can intuitively read the value of the vertical bearing capacity of the steel pipe pile.

[0014] Preferably, a bearing plate is provided on the top of the steel pipe pile, and a plurality of jacks are evenly arranged on the bearing plate around the center of the steel pipe pile.

[0015] The setting of the bearing plate can make the jacks more evenly distributed and the force stable.

[0016] Preferably, the load-bearing platform comprises a plurality of uniformly arranged steel beams.

[0017] Steel beams have large bearing capacity and stable structure, so the bearing platform is composed of evenly arranged steel beams.

[0018] The second technical solution adopted by the present invention is a construction method of an above-water steel pipe pile bearing capacity detection device, which is specifically implemented according to the following steps:

[0019] Step 1, install and debug the detection device; firstly, theoretically estimate the standard value of the vertical ultimate bearing capacity of a single pile, determine the size of the buoyancy airbag according to the weight of the pile, and the bearing capacity of the detection platform is greater than the theoretically estimated standard value of the vertical ultimate bearing capacity of a single pile, then install the buoyancy airbag on the bearing platform, install the force transmission structure and the dynamometer on the top of the steel pipe pile, then move the bearing platform to the center of the upper part of the steel pipe pile, and then install the displacement sensor;

[0020] Step 2: Perform a loading experiment: first, evenly place the load on the load-bearing platform and observe the displacement sensor;

[0021] Step 3: When the displacement value of the displacement sensor reaches the required value, stop loading the pile load and observe the force measurement value;

[0022] Step 4: Compare the dynamometer value with the theoretical bearing capacity value;

[0023] Step 5, disassemble the detection device; first evenly unload the piled objects, then move the bearing platform out of the steel pipe pile, float the bearing platform to storage, deflate the buoyancy airbag, and store it after disassembly.

[0024] Preferably, in step 1, the height of the bearing platform after the buoyancy airbag is installed is greater than the height of the steel pipe pile above water.

[0025] Preferably, the standard value of the ultimate lateral friction resistance of the pile, i.e., the q value, is found out according to the geological survey report, L is the thickness of the soil layer around the pile, d is the pile diameter, and the standard value of the ultimate vertical bearing capacity of the single pile, i.e., the Q value, is obtained by the formula Q=πqdL;

[0026] When the displacement value of the displacement sensor reaches the requirement, the value measured by the dynamometer is Q', which is the actual bearing capacity value of the steel pipe pile;

[0027] Compare Q and Q' again. When Q'>Q, construction can be carried out safely.

[0028] Beneficial effects of the present invention:

[0029] By evenly installing buoyancy airbags on the bearing platform, the bearing platform can stably support the piled objects, effectively avoiding the overturning of the bearing platform; the piled objects are evenly placed above the bearing platform, and the force is transmitted to the steel pipe piles through the force transmission structure to achieve the sinking of the steel pipe piles. The displacement sensor is used to observe the limit sinking displacement, and then the force meter value is observed. By comparing the value measured by the force meter with the theoretically calculated standard value of the single pile vertical limit bearing capacity, it is determined whether the steel pipe piles can be safely constructed; the detection device has a simple structure, can be detected intuitively, is easy to operate, and can effectively detect the actual bearing capacity of the steel pipe piles. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the main structure of the present invention;

[0031] Figure 2 It is a schematic diagram of the top view of the structure of the present invention;

[0032] Figure 3 It is a structural schematic diagram when the guide structure of the present invention is a guide ring;

[0033] Figure 4 This is a structural schematic diagram when the guide structure of the present invention is a guide frame.

[0034] Explanation of the reference numerals: 1-steel pipe pile; 2-buoyancy airbag; 3-bearing platform; 4-force transmission structure; 5-dynamometer; 6-displacement sensor; 7-guide structure; 8-guide ring; 9-guide frame; 10-bearing plate. DETAILED DESCRIPTION

[0035] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] In the description of the present invention, it should be understood that the terms "center, lateral, longitudinal, up, down, front, back, left, right, vertical, horizontal, top, bottom, inside, outside" and the like indicate directions or positional relationships based on the attached Figure 1 The orientation or positional relationship shown is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0037] The first technical solution of the present invention is a bearing capacity detection device for a water steel pipe pile, the main structural diagram of which is shown in FIG. Figure 1 As shown, the top view of the structure is as follows Figure 2 As shown, it includes at least three buoyancy airbags 2 evenly arranged around the steel pipe pile 1, a bearing platform 3 is provided on the buoyancy airbags 2, the bearing platform 3 is higher than the top of the steel pipe pile 1, a force transmission structure 4 is provided between the top of the steel pipe pile 1 and the bearing platform 3, and a dynamometer 5 is provided on the top of the force transmission structure 4; the detection device also includes a displacement sensor 6.

[0038] The installation position of the displacement sensor 6 is not fixed, and may be on the steel pipe pile 1 , or on the bearing platform 3 or the force transmission structure 4 .

[0039] The structure of the bearing platform 3 can be a plurality of steel beams evenly arranged horizontally and vertically. The preferred structural shape of the bearing platform 3 is a square. Four buoyancy airbags 2 are installed at the four corners below the bearing platform 3. The airbags can be inflated by a high-pressure air pump. The buoyancy airbags 2 are cube airbag bags. The cube airbag bags have good stability and are easy to process. The buoyancy airbags 2 are connected to the bearing platform 3 as a whole to form a bearing capacity detection platform for the steel pipe pile 1. First, the standard value of the vertical ultimate bearing capacity of a single pile is theoretically estimated. The size of the buoyancy airbag 2 is designed according to the weight of the pile. The bearing capacity of the detection platform must be greater than the theoretically estimated standard value of the vertical ultimate bearing capacity of a single pile so that the experiment can proceed smoothly. The piled material can be concrete blocks, soil, sand, etc.

[0040] By evenly installing buoyancy airbags 2 on the bearing platform 3, the bearing platform 3 can stably support the piled objects, effectively avoiding the overturning of the bearing platform 3; the piled objects are evenly placed on the bearing platform 3, and the force is transmitted to the steel pipe pile 1 through the force transmission structure 4 to realize the sinking of the steel pipe pile 1. After the displacement sensor 6 observes the limit sinking displacement, the force measurement 5 counts and compares the value measured by the force meter 5 with the theoretically calculated standard value of the single pile vertical limit bearing capacity to determine whether the steel pipe pile can be safely constructed.

[0041] The judgment process is as follows: according to the geological survey report, the standard value of the ultimate lateral friction resistance of the pile is found, that is, the q value, L is the thickness of the soil layer around the pile, d is the pile diameter, and the formula Q=πqdL is used to obtain the standard value of the ultimate vertical bearing capacity of the single pile, that is, the Q value; when the displacement value of the displacement sensor 6 reaches the requirement, the value measured by the dynamometer 5 is Q', and then Q and Q' are compared. When Q'>Q, construction can be carried out safely.

[0042] Another way to judge is to observe the value of the dynamometer 5 during the continuous loading of the pile. When the value reaches the Q value, check whether the displacement value of the displacement sensor 6 reaches the required value. When the actual displacement value is less than the ultimate bearing capacity displacement value, construction can be carried out safely.

[0043] The displacement value of the displacement sensor 6 is in accordance with the provisions of the specification manual. For example, when the sinking deformation exceeds 100 mm, the loading of the piled load can be stopped.

[0044] This detection device has a large structural size and is subject to large forces. Each component of the corresponding device has high structural bearing capacity requirements and the structure needs to be stable and reliable.

[0045] Since the bearing platform 3 is placed on the top of the steel pipe pile 1, in order to enable the bearing platform 3 to stably support the piled objects and avoid overturning, a guide structure 7 can be provided between the steel pipe pile 1 and the bearing platform 3 to relatively fix the positions of the steel pipe pile 1 and the bearing platform 3. One structure of the guide structure 7 is that a guide ring 8 is provided at the bottom center of the bearing platform 3, and the guide ring 8 is sleeved on the top of the steel pipe pile 1. The structural schematic diagram of the guide structure 7 when it is a guide ring 8 is shown in FIG. Figure 3 The setting of the guide ring 8 enables the steel pipe pile 1 to be located at the center of the bearing platform 3, so that the bearing platform 3 can stably support the piled objects.

[0046] Another structure of the guide structure 7 is a guide frame 9 fixed around the steel pipe pile 1. The guide frame 9 is used to fix the position of the buoyancy airbag 2. The position and number of the guide frame 9 correspond to the buoyancy airbag 2. The structural schematic diagram of the guide structure 7 when it is the guide frame 9 is as shown in FIG. Figure 4 The setting of the guide frame 9 enables the steel pipe pile 1 to be located at the center of the bearing platform 3, so that the bearing platform 3 can stably support the piled objects and avoid overturning.

[0047] The force transmission structure 4 has a large bearing capacity and high structural accuracy requirements. The force transmission structure 4 is set to multiple jacks that are evenly arranged to meet the detection requirements. The top of the jack is connected to a dynamometer 5, and the dynamometer 5 can intuitively read the value of the vertical bearing capacity of the steel pipe pile.

[0048] In order to make the jacks evenly distributed on the steel pipe pile 1 and to ensure stable force, a bearing plate 10 is provided on the top of the steel pipe pile 1 , and a plurality of jacks are evenly arranged on the bearing plate 10 around the center of the steel pipe pile 1 .

[0049] According to the geological survey report, the standard value of the ultimate side friction resistance of the pile, i.e., the q value, is found. L is the thickness of the soil layer around the pile, and d is the pile diameter. The formula Q=πqdL is used to obtain the standard value of the ultimate vertical bearing capacity of a single pile, i.e., the Q value. First, according to the theoretical calculation of the Q value, the parameter model of the dynamometer 6 is selected. According to the Q value and the number of jacks, the parameter model of the jack is selected. Then, according to the displacement value required by the specification, the displacement sensor 7 is selected.

[0050] The second technical solution of the present invention is a construction method of an above-water steel pipe pile bearing capacity detection device, which is specifically implemented according to the following steps:

[0051] Step 1, installation and debugging of the detection device; firstly, theoretically estimate the standard value of the vertical ultimate bearing capacity of a single pile, determine the size of the buoyancy airbag 2 according to the weight of the pile, and the bearing capacity of the detection platform is greater than the theoretically estimated standard value of the vertical ultimate bearing capacity of a single pile, then install the buoyancy airbag 2 on the bearing platform 3, install the force transmission structure 4 and the dynamometer 5 on the top of the steel pipe pile 1, then move the bearing platform 3 to the upper center position of the steel pipe pile 1, and install the displacement sensor 6; in order to enable the installed bearing platform 3 to be smoothly installed with the steel pipe pile 1, the height of the bearing platform 3 after the buoyancy airbag 2 is installed is greater than the water height of the steel pipe pile 1.

[0052] Step 2: Perform a loading experiment; first, place the load evenly on the carrying platform 3 and observe the displacement sensor 6.

[0053] Step 3: When the displacement value of the displacement sensor 6 reaches the required value, stop loading the pile and observe the value of the dynamometer 5.

[0054] Step 4, compare the value of the dynamometer 5 with the theoretical bearing capacity value; find out the standard value of the ultimate lateral friction resistance of the pile according to the geological survey report, that is, the q value, L is the thickness of the soil layer around the pile, d is the pile diameter, and the formula Q=πqdL is used to obtain the standard value of the vertical ultimate bearing capacity of the single pile, that is, the Q value;

[0055] When the displacement value of the displacement sensor 6 reaches the requirement, the value measured by the dynamometer 5 is Q', which is the actual bearing capacity value of the steel pipe pile 1;

[0056] Compare Q and Q' again. When Q'>Q, construction can be carried out safely.

[0057] Step 5, disassemble the detection device; first, unload the pile evenly, then move the bearing platform 3 out of the steel pipe pile 1, and float the bearing platform 3 to storage, then deflate the buoyancy airbag 2, and store it after disassembly.

[0058] In summary, in order to solve the problems mentioned in the prior art that the steel pipe piles are affected by the environment in which they are located, especially the bearing capacity of offshore steel pipe piles is difficult to obtain from theory, and the construction safety is poor. By evenly installing buoyancy airbags 2 on the bearing platform 3, the bearing platform 3 can stably support the piled objects, effectively avoiding the overturning of the bearing platform 3; the piled objects are evenly placed on the bearing platform 3, and then the force is transmitted to the steel pipe pile 1 through the force transmission structure 4 to achieve the sinking of the steel pipe pile 1, and the displacement sensor 6 is used to observe the limit sinking displacement, and then the force measurement 5 counts are observed. By comparing the measured value of the dynamometer 5 with the theoretically calculated single pile vertical limit bearing capacity standard value, it is determined whether the steel pipe pile can be safely constructed; the detection device has a simple structure, can be detected intuitively, is easy to operate in construction, and can effectively detect the actual bearing capacity of the steel pipe pile.

[0059] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0060] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A construction method for a bearing capacity detection device for a water steel pipe pile, characterized in that: The detection device comprises at least three buoyancy airbags (2) uniformly arranged around the steel pipe pile (1), a bearing platform (3) being provided on the buoyancy airbags (2), a force transmission structure (4) being provided between the top of the steel pipe pile (1) and the bearing platform (3), and a dynamometer (5) being provided on the top of the force transmission structure (4); The detection device further comprises a displacement sensor (6); a guide structure (7) is further provided between the steel pipe pile (1) and the buoyancy airbag (2) for fixing the positions of the steel pipe pile (1) and the buoyancy airbag (2) relative to each other; the guide structure (7) comprises a guide ring (8) provided at the bottom center of the bearing platform (3); the guide ring (8) is sleeved on the top of the steel pipe pile (1); the force transmission structure (4) is a jack; a bearing plate (10) is provided at the top of the steel pipe pile (1); a plurality of jacks are evenly arranged on the bearing plate (10) around the center of the steel pipe pile (1); Follow the steps below to implement it: Step 1, installing and debugging the detection device; firstly, theoretically estimate the standard value of the vertical ultimate bearing capacity of a single pile, determine the size of the buoyancy airbag (2) according to the weight of the piled load, and the bearing capacity of the detection platform is greater than the theoretically estimated standard value of the vertical ultimate bearing capacity of a single pile, then install the buoyancy airbag (2) on the bearing platform (3), install the force transmission structure (4) and the dynamometer (5) on the top of the steel pipe pile (1), then move the bearing platform (3) to the upper center position of the steel pipe pile (1), and install the displacement sensor (6); Step 2: Perform a loading experiment. First, evenly place the load on the load platform (3), and observe the displacement sensor (6). Step 3: When the displacement value of the displacement sensor (6) reaches the required value, stop loading the pile and observe the value of the dynamometer (5); Step 4, comparing the value of the dynamometer (5) with the standard value of the vertical ultimate bearing capacity of a single pile; Step 5, disassembling the detection device; first, evenly unload the piled material, then move the bearing platform (3) out of the steel pipe pile (1), float the bearing platform (3) to a storage location, deflate the buoyancy airbag (2), and store it after disassembly.

2. The construction method of the above-water steel pipe pile bearing capacity detection device according to claim 1, characterized in that: The bearing platform (3) comprises a plurality of uniformly arranged steel beams.

3. The construction method of the above-water steel pipe pile bearing capacity detection device according to claim 2, characterized in that: In step 1, the height of the bearing platform (3) after the buoyancy airbag (2) is installed is greater than the height of the steel pipe pile (1) above water.

4. The construction method of the above-water steel pipe pile bearing capacity detection device according to claim 3, characterized in that: According to the geological survey report, the standard value of the ultimate side friction resistance of the pile, i.e., the q value, is found. L is the thickness of the soil layer around the pile, d is the pile diameter, and the formula Q = πqdL is used to obtain the standard value of the ultimate vertical bearing capacity of a single pile, i.e., the Q value; When the displacement value of the displacement sensor (6) reaches the required value, the value measured by the dynamometer (5) is Q', that is, the actual bearing capacity value of the steel pipe pile (1); Compare Q and Q' again. When Q'>Q, construction can be carried out safely.

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