Method for judging whether bottom elevation of tubular pile reaches standard or not

Abstract

The invention discloses a method for judging whether the pile bottom elevation of a pipe pile reaches the standard or not, pile bottom control information is imported into a control system of a pile machine in advance, and the pile bottom control information comprises predicted pile bottom elevation information corresponding to each pile position; then, the coordinates of the pile position in construction are automatically recognized through a pile position recognition system, and the predicted pile bottom elevation corresponding to the pile position is determined in combination with pile bottom control information; meanwhile, the pile top elevation of the pipe pile being constructed is measured in real time, and the actual pile bottom elevation is obtained by combining the pile length; the actual pile bottom elevation is compared with the predicted pile bottom elevation, if the design requirement is met, it is considered that the pile bottom elevation of the tubular pile reaches the standard, and otherwise, the pile bottom elevation does not reach the standard. Whether the pipe pile bottom elevation reaches the standard or not can be automatically judged in real time, pipe pile construction can be accurately guided, the pipe pile construction quality is improved, human participation is not needed in the whole process, and the influence of human participation on the result is avoided.

Description

Technical Field

[0001] The invention relates to pipe pile construction process control, in particular to a method for judging whether a pipe pile bottom elevation reaches a standard or not, and belongs to the technical field of pipe pile construction. Background Art

[0002] Pile foundation is a foundation form with high bearing capacity, wide application range and long history. It is widely used in high-rise buildings, ports, bridges and other projects. It is mainly used to improve the bearing capacity of the foundation and is the most widely used deep foundation form. Pile foundation can be divided into two categories according to the construction method: cast-in-place piles and precast piles. Precast piles are increasingly widely used in the market due to their advantages such as visible and controllable quality, low cost, short construction period and clean site.

[0003] Prefabricated piles include wooden piles, steel piles, pipe piles, etc., among which pipe piles are the most widely used. The construction methods are generally hammering and static pressure. Hammering means driving the pipe piles into the ground with a pile driver.

[0004] One of the main control items of pile foundation quality is bearing capacity. The bearing capacity of pipe piles can be divided into two categories: end-bearing piles and friction piles. In the construction process, end-bearing piles generally adopt dual control, that is, the penetration and pile bottom elevation are required to meet the requirements at the same time. Generally, the penetration is controlled first, and the hammer is withdrawn after the penetration meets the requirements. After the hammer is withdrawn, it is verified whether the pile bottom elevation meets the requirements. If it does not meet the requirements, the subsequent treatment method will be discussed. Therefore, in the construction process of end-bearing piles, whether the pile bottom enters a certain depth of the bearing layer according to the design requirements has an important influence on the bearing capacity and is also an important control factor. In addition, the pile foundation project is a concealed project. After the pipe pile is driven into the ground, it is difficult to accurately measure its pile bottom elevation and it is not traceable. Therefore, it is easy to cause distortion of the pile bottom elevation due to human factors, which brings huge risks to the quality and safety of the pile foundation and also generates a lot of unnecessary costs for the construction unit. Therefore, how to objectively and accurately determine whether the pile bottom elevation of the pipe pile meets the standard during the construction process is particularly important, and it is also a technical problem that technicians in this field need to solve urgently.

[0005] The current method of measuring pile bottom elevation is generally to manually measure the pile top elevation first, and then calculate the pile bottom elevation based on the pile length data. Then, by manually checking the geological survey drilling data near the pile position, the bearing layer elevation information of the pile position is estimated, and combined with the designed bearing layer entry depth requirements, it is determined whether the pile bottom elevation of the pile position meets the standard. This process requires manual measurement of a large amount of data, which consumes manpower and is prone to data distortion caused by human factors. The bearing layer elevation information is manually estimated, which is greatly affected by the experience of the estimator and is difficult to guarantee accuracy. Summary of the invention

[0006] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a method for judging whether the bottom elevation of a pipe pile meets the standard. The present invention can automatically determine in real time whether the bottom elevation of the pipe pile meets the standard, which is conducive to accurately guiding the construction of the pipe piles and improving the quality of the construction of the pipe piles. The whole process does not require human participation, thus avoiding the influence of human participation on the results.

[0007] The technical solution of the present invention is achieved in this way: A method for judging whether the bottom elevation of a pipe pile meets the standard is carried out in the following steps: 1) Import the coordinates of each drilling point and the bearing layer elevation information in the geological survey drawings into the system platform, and import the coordinates of each pile position and the depth of each pile bottom into the bearing layer in the construction drawings into the system platform; the system platform generates a geological model based on the coordinates of each drilling point and the bearing layer elevation information, and then determines the estimated pile bottom elevation information of each pile position in combination with the coordinates of each pile position and the depth of each pile bottom into the bearing layer imported from the construction drawings; send the pile position coordinates and the estimated pile bottom elevation information as pile bottom control information to the control system on the pile driver; 2) The pile position identification system automatically identifies the coordinates of the pile position currently under construction and matches them with the coordinates of each pile position imported from the construction drawings to determine the pile position and pile position coordinates in the construction drawings corresponding to the pile position under construction. Combined with the pile bottom control information, the estimated pile bottom elevation information corresponding to the coordinates of the pile position under construction is determined; 3) Real-time measurement of the pile top elevation of the pipe pile under construction, and the actual pile bottom elevation can be obtained in real time based on the pile top elevation and the pile length; 4) Compare the actual pile bottom elevation with the estimated pile bottom elevation information obtained in step 2). If the difference between the two data meets the design requirements, it is considered that the pile bottom elevation meets the standard; otherwise, it does not meet the standard.

[0008] Furthermore, in step 3), the pile length is determined as follows: a) Importing construction drawing information into the pile driver control system in advance, the construction drawing information includes the coordinates of each pile position, the pipe pile specifications of each pile position and the weight P of the pipe pile per meter corresponding to the pipe pile specifications; the pipe pile specifications include the pipe pile diameter and wall thickness; b) When the pile is lifted by the lifting device on the pile driver, the weight acting on the lifting device during the lifting process is measured in real time, and the weight is transmitted to the control system in real time; when the weight fluctuation is less than the set value and lasts for more than the set time, it is considered that the pile is completely off the ground, and the weight at this time is the pile weight M; c) Automatically identify the coordinates of the pile position currently under construction through the pile position identification system, and combine it with the construction drawing information pre-imported into the control system in step a) to determine the weight P of the pile per meter at the pile position, that is, obtain the pile length L=M / P.

[0009] Furthermore, the pile position identification system includes a GNSS receiver, which is two GNSS receivers symmetrically arranged on the left and right sides along the longitudinal center of the pile driver platform. The two GNSS receivers are fixed to the positions of the pipe piles to be constructed and the three are located at the three vertices of an isosceles triangle. The coordinates of two vertices in the isosceles triangle are directly measured by the two GNSS receivers, and the coordinates of the third vertex are obtained by calculation. The coordinates of the third vertex are the coordinates of the pile position currently under construction.

[0010] Furthermore, antenna brackets are respectively provided at the positions of the two GNSS receivers on the pile driver platform, and the two GNSS receivers are arranged on the top ends of the corresponding antenna brackets.

[0011] Furthermore, the lifting device is a hook and there are two of them, each hook is provided with a weighing sensor, and during the lifting process, the sum of the readings of the two weighing sensors is the weight acting on the lifting device during the pipe pile lifting process.

[0012] Furthermore, the hoisting device is a hook and there are two of them. A winch is provided on the pile driver platform, a pile frame is provided in the center in front of the pile driver platform, a traction fixed pulley is provided on the upper end of the pile frame, each hook is connected to one end of a traction steel rope, and the other end of the traction steel rope is connected to the winch after changing direction through the traction fixed pulley; a weighing sensor is provided between the pile frame and the traction fixed pulley; during the lifting process, the reading of the weighing sensor is the weight acting on the hoisting device during the pipe pile lifting process.

[0013] Step 3) The middle pile length can also be determined by the following method: when the pipe pile is lifted by the lifting device on the pile driver, the weight acting on the lifting device during the lifting process of the pipe pile is measured in real time. The weight continues to increase to a certain value and then gradually stabilizes, and then drops sharply. The moment of the initial sharp drop is when the top of the pipe pile is inserted into the hammer cap and the bottom of the pipe pile touches the ground. The ground elevation and pile top elevation at this time are measured, and the pile length L = pile top elevation - ground elevation.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention imports the coordinate information and bearing layer elevation information of various geological survey holes into the system platform in advance. The system platform generates a geological model based on the imported information, and then combines the coordinates of each pile position imported through the construction drawings and the depth information of the bearing layer that the pile bottom should enter to determine the estimated pile bottom elevation information of each pile position. The pile position coordinates and the estimated pile bottom elevation information are sent to the control system on the pile driver as pile bottom control information, and then compared with the actual construction pile position coordinates to obtain the estimated pile bottom elevation information of the construction pile position. At the same time, the actual pile bottom elevation is obtained by real-time measurement of the pile top elevation and the pile length, so that it can be known whether the pile bottom elevation of the pipe pile meets the standard. The present invention can automatically determine whether the pile bottom elevation of the pipe pile meets the standard in real time, which is conducive to accurately guiding the construction of pipe piles and improving the quality of pipe pile construction. The whole process does not require human participation, avoiding the influence of human participation on the results.

[0015] In the present invention, the parameters that need to be measured include the pile top elevation, pile length, pile bottom elevation and pile position coordinates. These parameters are transmitted to the construction control system by the signal of the relevant measuring components, and the control system automatically solves them without human participation. These data directly enter the construction control system, and can be viewed by all parties, which is convenient for tracing. In addition to being used for judging whether the pile bottom elevation of the pipe pile of the present invention meets the standard, it can also be used for the calculation and process control of other indicators in the construction, effectively realizing the full supervision of the construction process, which is conducive to the improvement of construction quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 - Flow chart of the method for judging whether the bottom elevation of the pipe pile reaches the standard or not according to the present invention.

[0017] Figure 2 - Schematic diagram of the overall structure of the pile driver and its auxiliary mechanisms of the present invention.

[0018] Figure 3 - Schematic diagram of pipe pile lifting according to the present invention.

[0019] Figure 4 - Schematic diagram of the hammer frame displacement measuring mechanism of the present invention. DETAILED DESCRIPTION

[0020] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0021] The present invention provides a method for judging whether the pile bottom elevation is up to standard, which is carried out according to the following steps. Figure 1 , 1) The coordinates of each drilling point in the geological survey drawings and the bearing layer elevation information are imported into the system platform, and at the same time, the coordinates of each pile position in the construction drawings and the bearing layer depth information of each pile bottom should be imported into the system platform; the system platform generates a geological model based on the coordinates of each drilling point and the bearing layer elevation information, and then determines the estimated pile bottom elevation information of each pile position in combination with the coordinates of each pile position and the bearing layer depth information of the pile bottom imported through the construction drawings; the pile position coordinates and the estimated pile bottom elevation information are sent to the control system on the pile driver as pile bottom control information. Since the bearing layer elevation information of each drilling point is in the geological survey drawings, and these points are discrete, the present invention first fits the bearing layer elevation information corresponding to the discrete drilling points in the geological survey drawings into a continuous geological model that can know the bearing layer elevation information of any coordinate point, so that the estimated pile bottom elevation information corresponding to each pile position can be known by combining the coordinates of each pile position in the construction drawings and the bearing layer depth information of the pile bottom.

[0022] 2) The pile position identification system automatically identifies the coordinates of the pile position currently under construction and matches them with the coordinates of each pile position imported from the construction drawings to determine the pile position and pile position coordinates in the construction drawings corresponding to the pile position under construction. Combined with the pile bottom control information, the estimated pile bottom elevation information corresponding to the coordinates of the pile position under construction is determined; 3) Real-time measurement of the pile top elevation of the pipe pile under construction, and the actual pile bottom elevation can be obtained in real time based on the pile top elevation and the pile length; 4) Compare the actual pile bottom elevation with the estimated pile bottom elevation information obtained in step 2). If the difference between the two data meets the design requirements on the construction drawings, the pile bottom elevation is considered to meet the standard; otherwise, it does not meet the standard.

[0023] The present invention imports pile bottom control information including pile position coordinates and expected pile bottom elevation into the control system in advance, compares the pile bottom control information with the actual construction pile position coordinates, and obtains the expected pile bottom elevation information corresponding to the actual construction pile position. At the same time, the actual pile bottom elevation is obtained by real-time measurement of the pile top elevation and the pile length, so as to know whether the pile bottom elevation of the pipe pile meets the standard. The present invention can automatically determine whether the pile bottom elevation of the pipe pile meets the standard in real time, which is conducive to accurately guiding the construction of pipe piles and improving the quality of pipe pile construction. The whole process does not require human participation, thus avoiding the influence of human participation on the results.

[0024] It can be seen from the above description that the parameters that need to be known in the present invention are the pile length, pile top elevation, pile bottom elevation and pile position coordinates, which will be described one by one below.

[0025] 1. Pile length measurement.

[0026] There are many ways to measure pile length, and two of the more preferred ones are given below.

[0027] Pile length measurement method 1: a) Similar to the geological survey map, the construction drawing information is pre-imported into the pile driver control system. The construction drawing information includes the coordinates of each pile position, the pile specifications of each pile position, and the weight P of the pile per meter corresponding to the pile specifications; the pile specifications include the pile diameter and wall thickness; b) When the pipe pile is lifted by the hanger on the pile driver, the weight acting on the hanger during the lifting process of the pipe pile is measured in real time, and the weight is transmitted to the control system in real time; when the weight fluctuation is less than 50kg and lasts for more than 5 seconds, the pipe pile is considered to be completely off the ground, and the weight at this time is the weight M of the pipe pile. Since the pipe pile usually shakes when it is just lifted off the ground, the weight often fluctuates to a certain extent, and the maximum value that appears during the fluctuation process is usually larger than the actual weight of the pipe pile, so it is necessary to wait until the pipe pile is stable before taking a reading, and only then can the true weight of the pipe pile be obtained. If you have to wait until the reading has no fluctuation at all, it will take a long time, which will affect the construction efficiency and will not substantially improve the measurement results. Therefore, the present invention considers the pipe pile to be in a stable state when the fluctuation is small and lasts for a certain period of time, and such treatment will not affect the final pile length measurement result.

[0028] c) The pile position identification system automatically identifies the coordinates of the current pile position under construction, and combines them with the construction drawing information pre-imported into the control system in step a) to determine the weight P of the pipe pile per meter corresponding to the pile position, and the pipe pile length L=M / P can be obtained.

[0029] Pile length measurement method 2: The process of pipe pile lifting and piling is to first lift the hammer frame to a height slightly higher than the length of the pipe pile, then use the left and right hooks to pull the steel rope wrapped around the pipe pile, lift the pipe pile from the ground, and after the pipe pile is completely suspended in the air, put the pipe pile into the hammer cap on the hammer frame, and then slowly lower the hook until the pipe pile touches the ground. During the lowering of the pipe pile, the hammer frame drops synchronously, and the pile top remains in the hammer cap to prevent the pipe pile from tipping over. The weight of the pipe pile is mainly borne by the hook and then mainly borne by the ground. At this time, the force on the hook drops sharply. Method 2 is designed based on the characteristics of pipe pile construction, as follows.

[0030] When the pipe pile is lifted by the hoisting device on the pile driver, the weight acting on the hoisting device during the lifting process of the pipe pile is measured in real time. The weight continues to increase to a certain value and then gradually stabilizes, and then drops sharply. The moment of the initial sharp drop is when the top of the pipe pile is inserted into the hammer cap and the bottom of the pipe pile touches the ground at the same time. The ground elevation and pile top elevation at this time are measured, and the pile length L = pile top elevation - ground elevation.

[0031] Although both methods involve measuring the weight of the pipe pile, the pile length measurement principles are completely different. Method 1 directly uses the weight M as the basis for calculating the pile length. The weight of the pipe pile per meter is P, and M / P is the pile length L. Method 2 only uses the weight of the pipe pile obtained at a specific time as the time to measure the elevation. The weight of the pipe pile is not used in the actual calculation of the pile length. At this moment, the bottom of the pipe pile just touches the ground, so the pile length at this time is the difference between the ground elevation and the pile top elevation. By measuring the ground elevation and the pile top elevation, the pile length can be obtained.

[0032] The pile length measurement of the present invention involves hoisting, and the structures related to hoisting can be seen in Figure 2 and Figure 3 As can be seen from the figure, the sling is a hook 20 and there are two of them, and each hook 20 is provided with a weighing sensor 26. A winch 21 is provided on the pile driver platform 2, and a traction fixed pulley 22 is provided on the upper end of the pile frame 3. Each hook 20 is connected to one end of a traction steel rope 23, and the other end of the traction steel rope 23 is connected to the winch 21 after changing direction through the traction fixed pulley 22. The winch drives the traction steel rope to be retracted and released to achieve the lifting of the pipe pile. During the lifting process, the sum of the readings of the two weighing sensors 26 is the weight acting on the sling during the lifting process of the pipe pile. In actual operation, the measurement is started only when the sum of the readings of the two weighing sensors exceeds 1t, and the weight is monitored in real time. This is because the lifting weight may be greater than 1t after the lifting starts, and the lifting process only accounts for a small part of the entire construction process. Most of the time, it is not necessary to monitor the weight. The weight is monitored only after it exceeds 1t. This can save system resources and also reflect that the pile driver is currently in the lifting link of the operation.

[0033] In the above two pile length measurement methods, it is also possible to not set a weighing sensor on the hook, but to modify the traction fixed pulley 22 through which the traction steel rope 23 of the hook passes, that is, to set a weighing sensor between the pile frame 3 and the traction fixed pulley 22. During the lifting process, the reading of the weighing sensor is the weight acting on the hanger during the lifting process of the pipe pile. By measuring the change in the force of the traction fixed pulley through the weighing sensor, the weight of the pipe pile can also be measured based on the same principle.

[0034] The pile length measurement of the present invention is automatically realized in the lifting link of the pipe pile construction, without changing the existing lifting operation, and does not require human participation. It only needs to adapt the existing pile driver structure (add a weighing sensor on the hook or the traction fixed pulley), and the modification is simple. The present invention avoids the influence of human participation in the measurement process on the result, and saves labor costs. Method 1 calculates the length by the weight of the pipe pile. Since the pile length in the specification is an integer meter, such as 10 meters, 12 meters, and 15 meters, the final calculated pile length L is determined in meters and rounded according to the rounding rule. Therefore, even if there is a slight error in the weighing sensor during measurement, it will be offset by rounding and will not affect the final result. In method 2, the weight is only used to determine the elevation measurement time, and it is not used for pile length calculation itself, and the weight accuracy requirements are lower. Therefore, the two methods have lower requirements for the accuracy and installation of weight sensors, are cheap, and are easier to implement.

[0035] 2. Measure the pile top elevation.

[0036] In addition to being the basic data for pipe pile construction, the pile top elevation is also required in the present invention when determining the pile bottom elevation and when measuring the pile length in method 2; therefore, the measurement of the pile top elevation is an important part of the present invention.

[0037] In order to measure the pile top elevation, the present invention specifically proposes a structure for real-time measurement of the pile top elevation, see Figure 2 and Figure 4 , including a pile driver 1, the pile driver 1 includes a pile driver platform 2 and a pile frame 3 arranged in the middle of the front end of the pile driver platform, a hammer frame 5 is provided on the front side of the pile frame 3 through a hammer clamp 4, and the hammer frame 5 can be raised and lowered along the pile frame 3 through the hammer clamp 4 under the drive of a driving mechanism.

[0038] An antenna bracket 6 is provided on the pile driver platform 2, and a GNSS receiver 7 for detecting elevation is provided on the top of the antenna bracket 6. The present invention sets the GNSS receiver on the top of the antenna bracket, and the antenna bracket is located in an open position of the pile driver platform away from the pile frame, so that the influence of the pile frame, hammer frame, etc. on the GNSS receiver can be avoided, and the elevation measurement can be accurately performed.

[0039] The present invention also includes a hammer frame displacement measuring mechanism, see Figure 4 The hammer frame displacement measuring mechanism includes a pull rope 8, a deceleration mechanism and a displacement sensor 9. The deceleration mechanism includes a fixed pulley group composed of a plurality of fixed pulleys 10 and a movable pulley group composed of a plurality of movable pulleys 11. The fixed pulley group is located directly above the movable pulley group. All the fixed pulleys 10 are fixed on the pulley bracket 12 at intervals side by side horizontally, and all the movable pulleys 11 are fixed on the counterweight 13 at intervals side by side horizontally. One end of the pull rope 8 is fixed on the pulley bracket 12, and the other end of the pull rope is alternately bypassed from one side in the order of the fixed pulley 10 and the movable pulley 11, and then turned from the fixed pulley 10 to be led downward. The pull rope 8 led downward is changed in direction by the changing fixed pulley 14 and then vertically upward and fixedly connected to the hammer clamp 4; the pulley bracket 12 is fixed on the pile driver platform 2 and is located behind the pile frame 3; the displacement sensor 9 is connected to the counterweight 13 to detect the displacement of the counterweight after deceleration during the downward movement of the hammer frame; the deceleration mechanism is used to decelerate the displacement of the other end of the pull rope 8 and transmit it to the counterweight 13.

[0040] The displacement sensor of the present invention needs to measure the downward displacement of each hammer of the hammer frame throughout the whole process, and calculate the pile top elevation based on this. The speed span of the hammer frame at different stages is very large. In the early stage of hammering or when the geology is relatively soft, the hammer frame may fall several meters after one hammer is struck. In this case, the speed is very fast; while in the later stage of the pile being buried in the soil, the downward speed of each hammer is very slow, especially in the hammer-collecting stage, which is measured in millimeters. Therefore, the existing detection objects have put forward very high requirements on the displacement sensor. In the case of very fast speed, the displacement sensor may fail to detect. Based on this, the present invention uses a deceleration mechanism to decelerate the falling speed of the hammer frame 5 and then transmit it to the displacement sensor 9, ensuring that the displacement sensor 9 can detect reliably. The actual falling displacement of the hammer frame is the displacement detected by the displacement sensor multiplied by the deceleration ratio. In the embodiment, the downward speed of the hammer frame can be adjusted to 1 / 2-1 / 16 (actually 1 / 8 or 1 / 10) by using the pulley block as a deceleration mechanism. The hammer clamp and the pulley block are connected by a steel rope. A counterweight is used to pull the movable pulley block downward. A displacement sensor is connected to the counterweight. The relative position of the hammer and the pile driver plane can be obtained by combining the deceleration multiple. A GNSS receiver is installed on the pile driver plane to obtain the elevation of the pile driver plane. Combined with the relative position with the hammer and the hammer length, the top elevation of the pipe pile can be obtained.

[0041] The present invention only needs to calibrate the relevant constants in the early stage. In the later actual measurement, the displacement sensor is connected to the measurement system, and the measurement system reads the displacement sensor detection value in real time, and the measurement system can automatically calculate the real-time elevation of the pile top. In addition to being used to determine the pile bottom elevation and for measuring the length of the pipe pile in method 2, the pile top elevation can also be stored in the measurement system as construction data for controlling construction quality and cost settlement.

[0042] Furthermore, the displacement sensor 9 is an encoder, which is connected to the speed measuring fixed pulley 15 through a pulley shaft; one end of the speed measuring rope 16 is fixedly connected to the counterweight 13, and the other end is connected to the take-up device 17 after winding around the speed measuring fixed pulley 15. When the counterweight falls, the upper end of the speed measuring rope will fall with it, and the take-up device will tighten the speed measuring rope in real time, causing the speed measuring fixed pulley to rotate during the tightening process. The encoder can obtain the corresponding displacement according to the rotation angle and diameter of the speed measuring fixed pulley. The encoder technology is mature, with high measurement accuracy and reliable operation.

[0043] There are two direction-changing fixed pulleys 14, which are fixedly installed on the front and rear sides below the pile frame 3. The direction-changing fixed pulley located on the rear side of the pile frame is used to change the direction of the pull rope from vertically downward to forward; the direction-changing fixed pulley located on the front side of the pile frame is used to change the direction of the pull rope from forward to vertically upward. Through the two direction-changing fixed pulleys 14, the pull rope can be reliably changed in direction without interfering with the surroundings. In actual installation, the two direction-changing fixed pulleys do not necessarily need to be on the same horizontal line. The installation position of the front direction-changing fixed pulley needs to be as low as possible, but any position below the platform plane may be damaged by collision during the pipe pile lifting process, so it can only be installed above the platform. This is why a pull rope bracket (to be introduced below) is required.

[0044] Furthermore, a pull rope bracket 18 facing vertically upward is fixedly installed on the hammer clamp 4, and the other end of the pull rope 8 is fixed on the top of the pull rope bracket 18. The pull rope bracket should be installed inwardly so that the horizontal distance between the connection with the pull rope and the front direction-changing fixed pulley is 1-2 cm, which can avoid collision with the direction-changing fixed pulley and shorten the horizontal distance with the direction-changing fixed pulley as much as possible to reduce the impact of the deflection angle. Because the pile driver platform 2 has a certain height, the setting of the pull rope bracket 18 can ensure that the other end of the pull rope 8 is always facing upward when the pipe pile 19 is hammered. If the other end of the pull rope is lower than the pile driver platform, the steering fixed pulley will fail. In this case, the deeper the pipe pile is buried, the more the counterweight will be pulled upward through the pull rope, resulting in abnormal measurement of the pile top elevation. Even if the other end of the pull rope is above the platform, it is difficult to make the pull rope go straight up after passing the steering fixed pulley due to the actual installation environment. There will be a certain external deviation angle from the vertical direction. If the other end of the pull rope is close to the steering fixed pulley, the deviation angle will be more obvious. As a result, the small displacement of the other end of the pull rope (the displacement is very small in the hammer retraction stage) may be difficult to detect on the displacement sensor after deceleration, thereby affecting the measurement accuracy of the displacement sensor. In the embodiment, the hammer clamp 4 is arranged in two groups up and down, and the pull rope bracket 18 is fixedly installed vertically upward on the lower hammer clamp 4.

[0045] Furthermore, the pulley bracket 12 is a tubular structure with a closed upper end and an open lower end. The fixed pulley block, the movable pulley block, the counterweight 13, the displacement sensor 9, the speed measuring fixed pulley 15 and the take-up device 17 are all located in the tubular cavity; the other end of the pull rope 8 passes through the lower opening. The corresponding components are hidden inside the tubular cavity. On the one hand, the corresponding components are well protected to prevent interference and influence from external factors, so that they can work reliably; on the other hand, the overall structure looks simple and regular. At the same time, the tubular cavity has a restraining and limiting function to ensure that the counterweight moves up and down in the tubular cavity and avoid the scaling of the steel rope caused by the horizontal shaking of the counterweight. In the embodiment, rollers are respectively provided on both sides of the counterweight, and the counterweight is fitted with the inner wall of the tubular cavity through the rollers, so that the counterweight can descend more smoothly.

[0046] Based on the structure designed above for measuring the top elevation of pipe piles in real time, the present invention measures the top elevation of the piles in the following steps: S1) Constant C calibration; the pile 19 is hoisted to a vertical state by the pile driver 1 in advance; and the pile top elevation calibration reading X is measured according to the existing method. 桩0 ; Read the calibration elevation Y0 obtained by the GNSS receiver on the pile driver platform bracket, and get the pile top elevation X 桩0 The corresponding displacement sensor calibration reading is Z0; assuming the reduction ratio of the reduction mechanism is n, the calibration displacement of the other end of the rope is nZ0; there is the equation X 桩0 =Y0+nZ0+C; then the constant C=X 桩0 -Y0-nZ0. When measuring, the pile top elevation is calibrated to read X 桩0 It can be manually calibrated, that is, the GNSS receiver is placed directly on the top of the pile to measure its elevation. In order to prevent the high metal components around the GNSS receiver from affecting the measurement, the pile can be hammered into the ground to a certain depth (or hammered directly into place), and then Y0 and Z0 can be measured. Then, the pile can be kept still, the pile driver can be removed, and the GNSS receiver can be placed directly on the top of the pile to measure its elevation. This will allow accurate X0 and Z0 measurements to be obtained without interference. 桩0 ; S2) During the actual measurement, the displacement sensor reading Z is read in real time, and the real-time displacement of the other end of the rope is nZ; the elevation reading obtained by the GNSS receiver is Y; the real-time elevation of the pile top is X 桩 =Y+nZ+C.

[0047] The reduction ratio is 2-16.

[0048] Theoretically, the pile driver platform is required to be in a horizontal state during measurement. However, considering the complexity of the actual construction site environment, the pile driver platform is not always in a horizontal state and may be tilted between the left and right sides. In view of this, the present invention has two GNSS receivers on the left and right sides, which are symmetrically arranged along the longitudinal center of the pile driver platform. Y in step S2) is the arithmetic mean of the elevation readings obtained by the two GNSS receivers.

[0049] Similarly, there may be a certain degree of inclination between the front and the back. Different inclination angles will have different effects on the measurement results. To eliminate this effect, the present invention sets a constant A related to the inclination angle. The constant A is the straight-line distance from the line connecting the two GNSS receivers to the vertical center line of the hammer, which can be measured using a tape measure.

[0050] In the actual measurement of step S2), it is also necessary to measure the inclination angle θ of the pile driver platform relative to the horizontal plane by using an inclinometer, so the real-time elevation of the pile top is X 桩 =Y+nZ+C+A*tgθ.

[0051] In the pile length measurement method 2, in addition to knowing the pile top elevation, the ground elevation also needs to be known. To measure the ground elevation, the present invention installs a laser rangefinder 24 at the middle position of the front end of the pile driver platform 2, which is vertically downwardly aimed at the front leg 25 of the pile driver. When the front leg rises and falls, the laser rangefinder data changes by the same amount. A protective tube is installed at the front end of the laser rangefinder to prevent the laser rangefinder lamp from being dirty.

[0052] To measure the ground elevation, follow the steps below: 1) Constant E calibration: When the pile driver is in a stationary state, the ground elevation calibration reading X is measured according to the existing method (i.e., using a GNSS receiver, level or total station and other measuring equipment to manually measure the ground elevation). 地0 ; Read the calibration elevation Y1 obtained by the GNSS receiver on the pile driver platform bracket, and get the ground elevation X 地0 The laser rangefinder calibration reading F0 at the time of 地0 =Y1+F0+E; then the constant E=X 地0 -Y1-F0; 2) During actual measurement, the laser rangefinder reading F is read in real time; the elevation reading obtained by the GNSS receiver is Y; then the ground elevation X 地 =Y+F+E.

[0053] Considering the influence of the inclination angle of the pile driver platform, a constant A related to the inclination angle is set as in the pile top elevation measurement. The constant A is the straight-line distance from the line connecting the two GNSS receivers to the vertical center line of the hammer. In step 2), during the actual measurement, the inclination angle θ of the pile driver platform relative to the horizontal plane is measured at the same time. At this time, the ground elevation X 地 =Y+F+E+A*tgθ.

[0054] The present invention involves the elevation reading Y, constant A and tilt angle θ obtained by the GNSS receiver when measuring the ground elevation and the pile top elevation. Based on the measurement principles of the two, it can be known that the two share the elevation reading Y, constant A and tilt angle θ obtained by the same GNSS receiver.

[0055] 3. Determine the pile bottom elevation.

[0056] After the pile top elevation and pile length are determined, the subtraction between the two is the pile bottom elevation, that is, pile bottom elevation = pile top elevation - pile length.

[0057] 4. Determine the pile position coordinates.

[0058] The pile position coordinates of the present invention are automatically identified by the pile position identification system. The estimated pile bottom elevation can be determined by combining the pile position coordinates with the pile bottom control information, and the pile position coordinates can be determined by combining the construction drawings with the pipe pile information corresponding to the coordinates (pipe pile specifications and the weight per meter of the pipe pile corresponding to the pipe pile specifications). The main body of the pile position identification system of the present invention is the two GNSS receivers 7 introduced above. The two GNSS receivers 7 and the pipe piles 19 (or pile frames) to be constructed are fixed in position and the three are located at the three vertices of an isosceles triangle, that is, the three sides and three angles of the isosceles triangle are known. In addition to measuring elevation, the GNSS receiver can also measure the coordinates of the point. That is, the coordinates of two vertices (vertices corresponding to the two bottom angles) in the isosceles triangle are directly measured by the two GNSS receivers 7, and the coordinates of the third vertex (vertices corresponding to the top angle) are obtained by simple mathematical calculation based on the information of the isosceles triangle. The coordinates of the third vertex are the coordinates of the pile position of the current construction.

[0059] The coordinates of actual construction are often not completely consistent with the coordinates marked on the construction drawings, and there are some differences. By matching with the construction drawings, it is easy to determine that the pile position of actual construction corresponds to a certain pile position on the construction drawings. The estimated pile bottom elevation information of the pile position on the construction drawings can be obtained through the pile bottom control information. The estimated pile bottom elevation information of the actual construction pile position can be determined by referring to the elevation information of the corresponding pile position on the construction drawings.

[0060] It can be seen from the above records that the parameters that need to be measured in the present invention include pile top elevation, pile length, pile bottom elevation and pile position coordinates. These parameters are transmitted to the construction control system by the signal of the relevant measuring components, and are automatically solved by the control system without human participation. These data directly enter the construction control system, and can be viewed by all parties, which is convenient for tracing. In addition to being used for judging whether the pile bottom elevation of the pipe pile of the present invention meets the standard, it can also be used for the calculation and process control of other indicators in construction, effectively realizing the full supervision of the construction process, which is conducive to the improvement of construction quality.

[0061] Finally, it should be noted that the above examples of the present invention are merely examples for illustrating the present invention, and are not intended to limit the embodiments of the present invention. Although the applicant has described the present invention in detail with reference to the preferred embodiments, for those of ordinary skill in the art, other different forms of changes and modifications can be made based on the above description. It is impossible to list all the embodiments here. Any obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for judging whether the bottom elevation of a pipe pile meets the standard, characterized in that: Follow the steps below, 1) Import the coordinates of each drilling point and the bearing layer elevation information in the geological survey drawings into the system platform, and import the coordinates of each pile position and the depth of each pile bottom into the bearing layer in the construction drawings into the system platform; the system platform generates a geological model based on the coordinates of each drilling point and the bearing layer elevation information, and then determines the estimated pile bottom elevation information of each pile position in combination with the coordinates of each pile position and the depth of each pile bottom into the bearing layer imported from the construction drawings; send the pile position coordinates and the estimated pile bottom elevation information as pile bottom control information to the control system on the pile driver; 2) The pile position identification system automatically identifies the coordinates of the pile position currently under construction and matches them with the coordinates of each pile position imported from the construction drawings to determine the pile position and pile position coordinates in the construction drawings corresponding to the pile position under construction. Combined with the pile bottom control information, the estimated pile bottom elevation information corresponding to the coordinates of the pile position under construction is determined; 3) Real-time measurement of the pile top elevation of the pipe pile under construction, and the actual pile bottom elevation can be obtained in real time based on the pile top elevation and the pile length; 4) Compare the actual pile bottom elevation with the estimated pile bottom elevation information obtained in step 2). If the difference between the two data meets the design requirements, it is considered that the pile bottom elevation meets the standard; otherwise, it does not meet the standard.

2. The method for determining whether the bottom elevation of a pipe pile meets the standard according to claim 1, characterized in that: Step 3) The middle pile length is determined as follows: a) Importing construction drawing information into the pile driver control system in advance, the construction drawing information includes the coordinates of each pile position, the pipe pile specifications of each pile position and the weight P of the pipe pile per meter corresponding to the pipe pile specifications; the pipe pile specifications include the pipe pile diameter and wall thickness; b) When the pile is lifted by the lifting device on the pile driver, the weight acting on the lifting device during the lifting process is measured in real time, and the weight is transmitted to the control system in real time; when the weight fluctuation is less than the set value and lasts for more than the set time, it is considered that the pile is completely off the ground, and the weight at this time is the pile weight M; c) Automatically identify the coordinates of the pile position currently under construction through the pile position identification system, and combine it with the construction drawing information pre-imported into the control system in step a) to determine the weight P of the pile per meter at the pile position, that is, obtain the pile length L=M / P.

3. A method for determining whether the bottom elevation of a pipe pile meets the standard according to claim 1 or 2, characterized in that: The pile position identification system includes a GNSS receiver, which is two GNSS receivers symmetrically arranged on the left and right sides along the longitudinal center of the pile driver platform. The two GNSS receivers are fixed to the positions of the pipe piles to be constructed and the three are located at the three vertices of an isosceles triangle. The coordinates of two vertices in the isosceles triangle are directly measured by the two GNSS receivers, and the coordinates of the third vertex are obtained by calculation. The coordinates of the third vertex are the coordinates of the pile position currently under construction.

4. The method for judging whether the pile bottom elevation of a pipe pile meets the standard according to claim 3, characterized in that: Antenna brackets are respectively arranged at the positions of the two GNSS receivers on the pile driver platform, and the two GNSS receivers are arranged at the top ends of the corresponding antenna brackets.

5. The method for judging whether the bottom elevation of a pipe pile meets the standard according to claim 2, characterized in that: The lifting device is a hook and there are two of them, each hook is provided with a weighing sensor, and during the lifting process, the sum of the readings of the two weighing sensors is the weight acting on the lifting device during the pipe pile lifting process.

6. The method for judging whether the pile bottom elevation of a pipe pile meets the standard according to claim 2, characterized in that: The lifting device is a hook, and there are two of them. A winch is provided on the pile driver platform. A pile frame is provided in the center in front of the pile driver platform. A traction fixed pulley is provided on the upper end of the pile frame. Each hook is connected to one end of a traction steel rope, and the other end of the traction steel rope is connected to the winch after changing direction through the traction fixed pulley. A weighing sensor is provided between the pile frame and the traction fixed pulley. During the lifting process, the reading of the weighing sensor is the weight acting on the lifting device during the pipe pile lifting process.

7. The method for judging whether the bottom elevation of a pipe pile meets the standard according to claim 1, characterized in that: Step 3) The middle pile length is determined as follows: when the pipe pile is lifted by the lifting device on the pile driver, the weight acting on the lifting device during the lifting process of the pipe pile is measured in real time. The weight increases continuously to a certain value and then gradually stabilizes, and then drops sharply. The moment of the initial sharp drop is when the top of the pipe pile is inserted into the hammer cap and the bottom of the pipe pile touches the ground. The ground elevation and pile top elevation at this time are measured, and the pile length L = pile top elevation - ground elevation.

8. The method for judging whether the bottom elevation of a pipe pile meets the standard according to claim 1, characterized in that: In step 3), the pile top elevation is determined as follows: First, a structure for measuring the top elevation of a pipe pile in real time is designed. The structure for measuring the top elevation of a pipe pile in real time includes a pile driver. The pile driver includes a pile driver platform and a pile frame arranged in the middle of the front end of the pile driver platform. A hammer frame is arranged at the front side of the pile frame through a hammer clamp. The hammer frame can be raised and lowered along the pile frame through the hammer clamp under the drive of a driving mechanism. An antenna bracket is provided on the pile driver platform, and a GNSS receiver for detecting elevation is provided on the top of the antenna bracket; It also includes a hammer frame displacement measuring mechanism, which includes a pull rope, a speed reduction mechanism and a displacement sensor, wherein the speed reduction mechanism includes a fixed pulley group composed of a plurality of fixed pulleys and a movable pulley group composed of a plurality of movable pulleys, the fixed pulley group is located directly above the movable pulley group, all the fixed pulleys are fixed horizontally and spaced side by side on the pulley bracket, and all the movable pulleys are fixed horizontally and spaced side by side on the counterweight; one end of the pull rope is fixed on the pulley bracket, and the other end of the pull rope starts from one side and alternately passes through all the fixed pulleys and movable pulleys in the order of the fixed pulley and the movable pulley, and then is led out downward from the fixed pulley, and the pull rope led out downward is changed in direction by the changing fixed pulley and then vertically upward and fixedly connected to the hammer clamp; the pulley bracket is fixed on the pile driver platform and located behind the pile frame; the displacement sensor is connected to the counterweight to detect the displacement of the counterweight generated during the downward movement of the hammer frame; the speed reduction mechanism is used to reduce the displacement of the other end of the pull rope and transmit it to the counterweight; Then, based on the structure for real-time measurement of the pile top elevation, measure the pile top elevation in the following steps: S1) Constant C calibration: Use the pile driver to lift the pile to a vertical state in advance; and measure the pile top elevation calibration reading X according to the existing method. 桩0 ; Read the calibration elevation Y0 obtained by the GNSS receiver on the pile driver platform bracket, and get the pile top elevation X 桩0 The displacement sensor calibration reading Z0 at the time of the speed reduction mechanism is assumed to be n, and the calibration displacement of the other end of the rope is nZ0; the equation X 桩0 =Y0+nZ0+C; then the constant C=X 桩0 -Y0-nZ0; S2) During actual measurement, the displacement sensor reading Z is read in real time, and the real-time displacement of the other end of the rope is nZ; the elevation reading obtained by the GNSS receiver is Y; then the pile top elevation at this time is X 桩 =Y+nZ+C.

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