Real-time monitoring and evaluation method for construction quality of cast-in-situ bored pile

Abstract

The invention discloses a real-time monitoring and evaluation method for the construction quality of a cast-in-situ bored pile, and relates to the technical field of pile foundation construction quality detection.The real-time monitoring and evaluation method comprises the steps that S1, a construction quality evaluation index system is constructed; s2, obtaining index layer monitoring data corresponding to the construction quality evaluation index system; s3, calculating the correlation degree of the index layer monitoring data and the construction standard value by adopting an absolute value grey proximity correlation degree method; s4, calculating an index layer combination weight corresponding to the construction quality evaluation index system by adopting an AHP-entropy weight combination weighting method; and S5, calculating a comprehensive evaluation vector by adopting a fuzzy comprehensive evaluation method, and determining the construction process quality of the cast-in-situ bored pile according to the comprehensive evaluation vector. Compared with the prior art, the quality of the cast-in-situ bored pile in the construction process can be monitored in real time, construction problems can be found in time, adjustment stop or reworking is avoided, the construction period is shortened, and the construction cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of pile foundation construction quality inspection, and particularly relates to a method for real-time monitoring and evaluation of the construction quality of bored cast-in-place piles. Background Art

[0002] As a concealed project, bored cast-in-place piles have multiple construction procedures, difficult quality control, and low automation. At present, most of the construction of bored cast-in-place piles in China still relies on manual operation, and the construction quality has high requirements for the technical level and personal qualities of operators.

[0003] The existing quality inspection of bored cast-in-place piles generally conducts sampling inspection on the construction results. Affected by the subjectivity of personnel and the limitations of sampling inspection methods, the effect of construction quality inspection is usually not ideal. The existing quality inspection of bored cast-in-place piles is usually carried out after the construction is completed, which has hysteresis. Once the pile foundation quality is detected to be unqualified, mediation or rework is required, affecting the construction period and increasing costs. In addition, the existing quality inspection of bored cast-in-place piles usually focuses on the quality inspection of the formed piles after the construction is completed, lacking the inspection of the construction process quality of bored cast-in-place piles, which is not conducive to the timely discovery of problems in the construction process.

[0004] In view of this, how to provide a device and method for inspecting the construction process quality of bored cast-in-place piles is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for real-time monitoring and evaluation of the construction quality of bored cast-in-place piles to solve the problems existing in the prior art.

[0006] To achieve the above purpose, the present invention provides a method for real-time monitoring and evaluation of the construction quality of bored cast-in-place piles, including:

[0007] S1: Construct a construction quality evaluation index system, including a drilling project layer, a pile position project layer, a mud project layer, and a pile body project layer; the drilling project layer includes a drilling depth index layer, a drilling verticality index layer, a drilling hole collapse index layer, a sediment thickness index layer, and a wellbore wall quality index layer; the pile position project layer includes a pile position coordinate index layer; the mud project layer includes a mud viscosity index layer and a mud specific gravity index layer; the pile body project layer includes a steel cage length index layer, a steel cage verticality index layer, a concrete pouring uniformity index layer, a sediment thickness index layer, and a wellbore wall quality index layer;

[0008] S2: Obtain the index layer monitoring data corresponding to the construction quality evaluation index system;

[0009] S3: Based on the index layer monitoring data and construction specification values obtained in step S2, use the absolute value grey approximate correlation degree method to calculate the correlation degree between the index layer monitoring data and the construction specification values;

[0010] S4: Based on the correlation degree between the monitoring data of the index layer calculated in step S3 and the construction specification values, use the AHP-entropy weight combined weighting method to calculate the combined weight of the index layer corresponding to the construction quality evaluation index system.

[0011] S5: Based on the combined weight of the index layer obtained in step S4, use the fuzzy comprehensive evaluation method to calculate the comprehensive evaluation vector, and determine the construction quality of the bored cast-in-place pile according to the comprehensive evaluation vector.

[0012] Further, in step S4, construct a project layer judgment matrix and an index layer judgment matrix according to the construction quality evaluation index system; based on the correlation degree between the monitoring data of the index layer calculated in step S3 and the construction specification values, calculate the subjective weight of the index layer corresponding to the construction quality evaluation index system through the project layer judgment matrix and the index layer judgment matrix, use the entropy weight method to calculate the objective weight of the index layer corresponding to the construction quality evaluation index system, and use the combined weighting method to determine the combined weight.

[0013] Further, there is a fixed sleeve inside the drill pipe, and an inertial measurement unit is arranged at a position of the fixed sleeve close to the drill bit; the inertial measurement unit is used to measure the real-time drilling depth of the drill bit, and then obtain the index layer of the drilling depth.

[0014] Further, a biaxial angle sensor is arranged on the truss of the collar turntable of the drill pipe; the biaxial angle sensor is used to measure the inclination of the collar turntable, and then obtain the index layer of the drilling verticality.

[0015] Further, a float level gauge is suspended in the mud pit or the casing, a torque measurement unit is arranged on the bearing of the drill bit, and an online rotational viscometer is arranged at a position in the mud pit close to the mud delivery pipe;

[0016] The online rotational viscometer is used to monitor the viscosity of the mud and then obtain the index layer of the mud viscosity;

[0017] When the float level gauge measures that the mud level rises, the torque measurement unit measures that the torque of the drill bit increases, and the online rotational viscometer measures that the viscosity of the mud increases, it is determined that the drilling hole collapses, and then the index layer of the drilling hole collapse is obtained.

[0018] Further, after hole cleaning, the drill bit rotates reversely from the bottom of the hole and the drill bit is lifted. The torque of the drill bit during the lifting process of the drill bit is monitored through the torque measurement unit, and the lifting height of the drill bit is recorded through the inertial measurement unit. When the torque becomes smaller, the height corresponding to the drill bit is determined as the sediment height, and then the index layer of the sediment thickness is obtained.

[0019] Further, a micro-resistivity three-dimensional scanning logging tool is set at the central position of the bottom of the steel reinforcement cage. The micro-resistivity three-dimensional scanning logging tool is lowered together with the steel reinforcement cage. Based on the resistivity difference between the wellhead and the bottom hole wall of the wellbore, the boundary line between the mud and the wellbore wall is identified, so as to judge whether the wellbore wall is regular and obtain the quality index layer of the wellbore wall.

[0020] After the concrete is poured, the micro-resistivity three-dimensional scanning logging tool is lifted upward. Based on the resistivity difference between the bottom and the wellhead of the wellbore wall, the uniformity of the pile body concrete pouring is judged, so as to obtain the concrete pouring uniformity index layer.

[0021] Further, a GNSS locator is set at the top of the construction pile frame, and a GNSS receiver is set on the platform of the construction pile frame. The GNSS locator monitors its relative distance from the drill pipe, determines the pile position coordinates, and further obtains the pile position coordinate index layer.

[0022] Further, an insertion type tuning fork is set in the mud pit; the insertion type tuning fork is used to detect the mud specific gravity, and further obtain the mud specific gravity index layer.

[0023] Further, a cross-shaped horizontal connecting rod is set at the top of the steel reinforcement cage, infrared laser rangefinders are set at the four ends of the cross-shaped horizontal connecting rod, and an infrared laser counter is set on the inner side wall of the casing. The infrared laser counter is close to the upper edge of the casing; when the steel reinforcement cage is lowered, the infrared laser counter records the start of the steel reinforcement cage entering the drilling hole, and the infrared laser rangefinders record the lowering depth and speed of the steel reinforcement cage, and further obtain the steel reinforcement cage length index layer; when the lowering depths of the steel reinforcement cage recorded by the infrared laser rangefinders at the four ends are inconsistent, it is determined that the verticality of the steel reinforcement cage is unqualified, and further obtain the steel reinforcement cage verticality index layer.

[0024] The present invention discloses the following technical effects:

[0025] Based on a number of representative indicators in the construction process of bored cast-in-place piles, the present invention constructs a construction quality evaluation index system, monitors various indicators in real time during the construction process, calculates the combined weight of the index layer corresponding to the construction quality evaluation index system by comparing the correlation between the detected indicators and the construction specification values, so as to obtain a comprehensive evaluation vector, and determines the construction process quality of the bored cast-in-place pile according to the comprehensive evaluation vector. Compared with the prior art, it can monitor the quality of the bored cast-in-place pile construction process in real time, timely discover construction problems, avoid mediation or rework, save construction period, and reduce construction costs. Description of the Drawings

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0027] Figure 1 It is the layout diagram of the present invention;

[0028] Figure 2 It is the schematic diagram of the steel reinforcement cage;

[0029] Among them, 1. GNSS locator; 2. GNSS receiver; 3. Inertial measurement unit; 4. Biaxial angle sensor; 5. Inserted tuning fork; 6. On-line rotational viscometer; 7. Float level gauge; 8. Torque measurement unit; 9. Infrared laser rangefinder; 10. Infrared laser counter; 11. Micro-resistivity three-dimensional scanning logging tool. Specific implementation manners

[0030] In the retrieved prior art:

[0031] CN109457691B discloses an integrated monitoring device and its control method for the hole forming and pile forming of deep water bored cast-in-place piles. The monitoring device includes a deep water bored cast-in-place pile casing for enclosing the deep water bored cast-in-place pile, and a hole forming and pile forming monitoring mechanism arranged on the inner wall of the deep water bored cast-in-place pile casing; the hole forming and pile forming monitoring mechanism includes a plurality of reinforcing rib structures vertically arranged on the inner wall of the deep water bored cast-in-place pile casing, a detection structure main body arranged in the reinforcing rib structure, and a monitoring control structure connected to the detection structure main body, and the monitoring control structure is arranged outside the deep water bored cast-in-place pile casing; the detection structure main body is set as an ultrasonic transmitting and receiving device, or a radar device, or a sonar device, or a CT device, or a thermal imaging device, or an infrared device. This patent monitors fewer construction quality indicators, and the sensitivity of the received signals of radar and ultrasonic waves is weak during underwater construction, making it difficult to achieve its ideal effect.

[0032] CN112160743B discloses a method for detecting the perpendicularity of a drill hole. By lowering a circular ring body into the drill hole until the circular ring body is close to the hole wall of the drill hole, the inclination angle of the drill hole is deduced. A device for measuring the perpendicularity of a drill hole and a pile body is adopted, including a circular ring body, a cord and a marker. One end of the cord is connected to the center of the circular ring body, and the marker is movably arranged on the cord. The detection method includes the following steps: after core drilling the pile body, filling the drill hole with water; putting the circular ring body into the drill hole, lowering the cord and exposing the marker above the water surface; once the circular ring body is close to the hole wall of the drill hole, stop lowering the cord; measure the distance S between the marker and the center of the drill hole, and measure the length L of the cord below the water surface, then the inclination angle of the drill hole: α = arctan(S / L). This patent is too idealistic in considering the construction process. In the actual drilling process, the inclination angle may change continuously and is not a consistent inclination. Moreover, this method can only be used for inspection after construction is completed and cannot achieve real-time verification during construction.

[0033] CN118029457B discloses a detection device and control method for reinforced concrete cast-in-place piles based on resistivity tomography, which relates to the technical field of quality detection of reinforced concrete cast-in-place piles. This application includes a number of embedded detection electrodes and a number of electrode caps; each embedded detection electrode is respectively connected to a first matrix switch, and each electrode cap is respectively connected to a second matrix switch; the first matrix switch and the second matrix switch are connected to a voltage detection circuit through a first selector, the first matrix switch and the second matrix switch are connected to a current source circuit through a second selector, and the voltage detection circuit is connected to a computer; the control pins of the first matrix switch, the second matrix switch, the first selector, and the second selector are connected to the computer; the reinforced concrete cast-in-place pile is divided into an intermediate measurement area surrounded by electrode caps and a number of peripheral measurement areas surrounded by the cooperation of electrode caps and embedded detection electrodes. The intermediate measurement area and each peripheral measurement area meet the conditions for resistivity tomography imaging to perform resistivity tomography imaging. The detection scheme of this patent is too complex. It is necessary to drill holes around the pile hole and there is also a complex circuit control system, which is difficult to apply in the actual construction of each cast-in-place pile.

[0034] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0035] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

[0036] An embodiment of the present invention provides a method for real-time monitoring and evaluation of the construction quality of bored cast-in-place piles, including:

[0037] S1: Construct a construction quality evaluation index system, including a drilling project layer, a pile position project layer, a mud project layer, and a pile body project layer; the drilling project layer includes a drilling depth index layer, a drilling verticality index layer, a drilling collapse index layer, a sediment thickness index layer, and a wellbore wall quality index layer; the pile position project layer includes a pile position coordinate index layer; the mud project layer includes a mud viscosity index layer and a mud specific gravity index layer; the pile body project layer includes a steel cage length index layer, a steel cage verticality index layer, a concrete pouring uniformity index layer, a sediment thickness index layer, and a wellbore wall quality index layer;

[0038] S2: Obtain the index layer monitoring data corresponding to the construction quality evaluation index system;

[0039] S3: Based on the index layer monitoring data obtained in step S2 and the construction specification values, use the absolute value grey proximity correlation degree method to calculate the correlation degree between the index layer monitoring data and the construction specification values;

[0040] (1) Determine the data sequence

[0041] Extract the real-time quality monitoring data recorded every minute. Suppose there are n quality monitoring data for the quality monitoring index i, and the set of these data constitutes the quality monitoring data sequence X i ;

[0042] X i = x i (1), x i (2), …, x i (n)

[0043] Each quality monitoring index corresponds to a specification value x0(n), and the set of specification values constitutes the specification sequence X0;

[0044] X0 = x0(1), x0(2), …, x0(n)

[0045] If the specification value is a given interval range value, take x0 equal to the average of the upper and lower limit values of the range.

[0046] (2) Correlation degree calculation

[0047] Considering that quality indicators should not compensate for each other's defects, abandon the traditional proximity correlation model that only considers the area between broken lines, and adopt the absolute value area and area difference calculation method to effectively prevent the positive and negative quality indicator effects from canceling each other out.

[0048] It is known that X i has the same length as X0, and let

[0049]

[0050] Then:

[0051]

[0052] ρ i0 represents the closeness between the monitoring value and the specification value of the i-th index during the construction of the foundation pile.

[0053] S4: Construct the project-level judgment matrix and the index-level judgment matrix according to the construction quality evaluation index system; based on the correlation degree between the index-level monitoring data and the construction specification values calculated in step S3, calculate the subjective weights of the index level corresponding to the construction quality evaluation index system through the project-level judgment matrix and the index-level judgment matrix, calculate the objective weights of the index level corresponding to the construction quality evaluation index system using the entropy weight method, and determine the combined weights using the method of combined weighting;

[0054] (1) Calculation of subjective weights

[0055] Adopt the analytic hierarchy process, including: constructing the index system, constructing the judgment matrix, calculating the weight coefficient vector of the judgment matrix, consistency test, and finally hierarchical ranking.

[0056] (2) Calculation of objective weights

[0057] Adopt the entropy weight method, and the entropy weight reflects the amount of useful information provided by each index for decision-making evaluation.

[0058] The calculation steps are as follows:

[0059] ① Construct the judgment matrix of m foundation piles and r indexes

[0060] D pi =[ρ pi p = 1, 2,..., m; i = 1, 2,..., r

[0061] In the formula, ρ pi is the i-th index of the p-th pile foundation.

[0062] ② Normalize the judgment matrix

[0063] ③ For the r evaluation indexes, the entropy of the i-th evaluation index is

[0064]

[0065] ④ The entropy weight of the i-th evaluation index is

[0066]

[0067] w″ i is the objective weight value of the i-th evaluation index, and the objective weight vector W″ = (w″1, w″2,..., w″n ) T 。

[0068] (3) Comprehensive weight calculation

[0069] To avoid the defects of subjective weight and objective weight themselves. Let the comprehensive weight vector of each index be W = (w1, w2,..., w r ) T , then the comprehensive weight w i of the i-th index is

[0070] w i = (1 - δ)w i '+ δw i ″

[0071] In the formula:

[0072] δ is the weight linear combination index, satisfying 0 ≤ δ ≤ 1;

[0073] When δ = 0, only subjective judgment of personnel can be provided during evaluation;

[0074] When δ = 1, only objective evaluation can be provided during evaluation;

[0075] When δ = 0.5, the accuracies of both are roughly equivalent during evaluation;

[0076] If there are differences in the accuracies of the two, δ can be flexibly selected.

[0077] S5: Based on the combined weights of the index layer obtained in step S4, use the fuzzy comprehensive evaluation method to calculate the comprehensive evaluation vector, and determine the quality of the bored pile construction process according to the comprehensive evaluation vector. Based on fuzzy mathematics, construct a membership function, and comprehensively judge by methods such as the maximum membership principle or weighted average. The steps are as follows:

[0078] (1) Determine the factor set: Based on the established evaluation index system and the threshold of the evaluation standard for the construction process quality indicators, express the correlation degree of the monitored values of each evaluation index corresponding to the specification values as: U = (u1, u2,..., u i ).

[0079] (2) Determine the scheme set: Divide the quality of the index construction process into excellent, qualified, and unqualified.

[0080] (3) Establish a membership function

[0081] The relationship between the factor set and the scheme set is expressed through the membership function. Select the membership function with a trapezoidal distribution.

[0082] Excellent Qualified Unqualified

[0083] a, b, c, and d represent the boundary values of the membership function distribution. The boundary values corresponding to different indicators are different and are determined by the specification values.

[0084] The fuzzy evaluation matrix of r indicators can be expressed as:

[0085]

[0086] (4) Calculate the comprehensive evaluation vector

[0087]

[0088] In the formula, H p is the comprehensive evaluation vector; W is the comprehensive weight matrix; (h1, h2, h3) are the membership degrees of the quality of the pile foundation construction process with respect to the first, second, and third evaluation comments; represents the fuzzy composition operator. In this paper, the M(·, ⊕) operator is selected.

[0089] In this embodiment, a fixed sleeve is provided inside the drill pipe, and an inertial measurement unit 3 is arranged at a position of the fixed sleeve close to the drill bit; the inertial measurement unit 3 is used to measure the real-time drilling depth of the drill bit, and then obtain the drilling depth index layer.

[0090] In this embodiment, a biaxial angle sensor 4 is arranged on the truss of the collar turntable of the drill pipe; the biaxial angle sensor 4 is used to measure the inclination of the collar turntable, and then obtain the drilling verticality index layer.

[0091] In this embodiment, a float level gauge 7 is suspended in the mud pit or the casing, a torque measurement unit 8 is arranged on the bearing of the drill bit, and an on-line rotational viscometer 6 is arranged at a position in the mud pit close to the mud delivery pipe;

[0092] The on-line rotational viscometer 6 is used to monitor the viscosity of the mud and then obtain the mud viscosity index layer;

[0093] When the float level gauge 7 measures an increase in the mud level, the torque measurement unit 8 measures an increase in the drill bit torque, and the on-line rotational viscometer 6 measures an increase in the mud viscosity, it is determined that the drilling has caved in, and then the drilling caving index layer is obtained.

[0094] In this embodiment, after hole cleaning, the drill bit rotates reversely from the bottom of the hole and the drill bit is lifted. The torque of the drill bit during the lifting process of the drill bit is monitored by the torque measurement unit 8, and the lifting height of the drill bit is recorded by the inertial measurement unit 3. When the torque becomes smaller, the height corresponding to the drill bit is determined as the sediment height, and then the sediment thickness index layer is obtained.

[0095] In this embodiment, a micro-resistivity three-dimensional scanning logging tool 11 is arranged at the central position of the bottom of the steel reinforcement cage. The micro-resistivity three-dimensional scanning logging tool 11 is fixed by a fixed hoisting rope, and the fixed hoisting rope is circularly tied. The micro-resistivity three-dimensional scanning logging tool 11 is lowered together with the steel reinforcement cage, and based on the resistivity difference between the wellhead and the bottom hole wall of the wellbore, the boundary line between the mud and the wellbore wall is identified, so as to judge whether the wellbore wall is regular and obtain the wellbore wall quality index layer;

[0096] After the concrete is poured, the fixed hoisting rope is cut, and the micro-resistivity three-dimensional scanning logging tool 11 is lifted upward. Based on the resistivity difference between the bottom and the wellhead of the wellbore wall of the wellbore, the uniformity of the pile body concrete pouring is judged, so as to obtain the concrete pouring uniformity index layer and predict the possible pile breaking situation.

[0097] In this embodiment, a GNSS locator 1 is arranged at the top of the construction pile frame, and a GNSS receiver 2 is arranged on the platform of the construction pile frame. The GNSS locator 1 monitors its relative distance from the drill pipe to determine the pile position coordinates, and then obtains the pile position coordinate index layer.

[0098] In this embodiment, an insertion type tuning fork 5 is arranged in the mud pit; the insertion type tuning fork 5 is used to detect the mud specific gravity, and then obtain the mud specific gravity index layer.

[0099] In this embodiment, a cross-shaped horizontal connecting rod is arranged at the top of the steel reinforcement cage, and infrared laser rangefinders 9 are arranged at the four ends of the cross-shaped horizontal connecting rod. An infrared laser counter 10 is arranged on the inner side wall of the casing, and the infrared laser counter 10 is close to the upper edge of the casing; when the steel reinforcement cage is lowered, the infrared laser counter 10 records the start of the steel reinforcement cage entering the drilling hole, and the infrared laser rangefinders 9 record the lowering depth and speed of the steel reinforcement cage, and then obtain the steel reinforcement cage length index layer; when the lowering depths of the steel reinforcement cage recorded by the infrared laser rangefinders 9 at the four ends are inconsistent, it is determined that the verticality of the steel reinforcement cage is unqualified, and then the steel reinforcement cage verticality index layer is obtained.

[0100] In this embodiment, the models of the above-mentioned devices are as follows:

[0101] The manufacturer of the GNSS locator 1 is Xiamen Jixun Internet of Things Technology Co., Ltd., with the model TN521. The manufacturer of the inertial measurement unit 3 is Beiwei Sensing Technology Co., Ltd., with the model IMU400C. The manufacturer of the biaxial angle sensor 4 is Shenzhen Weite Intelligent Technology Co., Ltd., with the model SINDT-485. The manufacturer of the insertion type tuning fork 5 is Shanghai Chicontrol Automation Instrument Co., Ltd., with the model CK-YCMD-2-TL. The manufacturer of the on-line rotational viscometer 6 is Jiangsu Jinglai Electronic Technology Development Co., Ltd., with the model JS-ND. The manufacturer of the float level gauge 7 is Shanghai Feizhuo Technology Co., Ltd., with the flange type. The manufacturer of the infrared laser rangefinder is Shenzhen Ruixingjia Electronic Co., Ltd., with the model GLM100-25C. The manufacturer of the infrared laser counter 10 is Huchentai Hardware Tools Franchise Store, with the model JDM11. The manufacturer of the micro-resistance three-dimensional scanning logging tool is Beijing Huanding Technology Co., Ltd., with the model WDSC.

[0102] Application Example

[0103] The renovation project of the 220 kV Nantong Haian Substation is located in Dingjiaqiao Village, Chengdong Town, northern part of Haian City, Nantong City, Jiangsu Province. The pile foundation form of this project is bored cast-in-place pile, with the pile diameter D being 600 mm and the effective pile length being about 27 m. The total number of pile foundations is 350. The equipment is installed in the above manner and real-time monitoring is carried out.

[0104] The following are the real-time monitoring indicators of pile positions Z0012 and Z0103.

[0105] Table 1 Monitoring of Indexes during the Drilling Stage of Pile Position Z0012

[0106]

[0107]

[0108]

[0109] Table 2 Monitoring of Indexes during the Hole-Forming Stage of Pile Position Z0012

[0110]

[0111]

[0112] Table 3 Monitoring of Indexes during the Drilling Stage of Pile Position Z0103

[0113]

[0114]

[0115]

[0116] Table 4 Monitoring of Indexes during the Hole-Forming Stage of Pile Position Z0103

[0117]

[0118]

[0119] As can be seen from the above table, the comprehensive evaluation calculation results of the construction process quality of pile positions Z0012 and Z0103 are

[0120]

[0121] According to the principle of taking the larger value, the evaluation results of the construction process quality of the test bored cast-in-place piles are as follows: for pile position Z0012, the value 0.507 belonging to the qualified level is the largest, so it is determined that the construction process quality of pile position Z0012 is qualified; for pile position Z0103, the value 0.612 belonging to the excellent level is the largest, so it is determined that the construction process quality of pile position Z0103 is excellent.

[0122] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0123] The above-described embodiments are only used to describe the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A real-time monitoring and evaluation method for the construction quality of bored cast-in-place piles, characterized in that, Including: S1: Construct a construction quality evaluation index system, including a drilling project layer, a pile position project layer, a mud project layer, and a pile body project layer; the drilling project layer includes a drilling depth index layer, a drilling verticality index layer, a drilling hole collapse index layer, a sediment thickness index layer, and a wellbore wall quality index layer; the pile position project layer includes a pile position coordinate index layer; the mud project layer includes a mud viscosity index layer and a mud specific gravity index layer; the pile body project layer includes a steel cage length index layer, a steel cage verticality index layer, a concrete pouring uniformity index layer, a sediment thickness index layer, and a wellbore wall quality index layer; S2: Obtain the index layer monitoring data corresponding to the construction quality evaluation index system; S3: Based on the index layer monitoring data and construction specification values obtained in step S2, use the absolute value grey proximity correlation degree method to calculate the correlation degree between the index layer monitoring data and the construction specification values; S4: Based on the correlation degree between the index layer monitoring data and the construction specification values calculated in step S3, use the AHP-entropy weight combined weighting method to calculate the combined weight of the index layer corresponding to the construction quality evaluation index system; S5: Based on the combined weight of the index layer obtained in step S4, use the fuzzy comprehensive evaluation method to calculate the comprehensive evaluation vector, and determine the quality of the bored pile construction process according to the comprehensive evaluation vector.

2. The real-time monitoring and evaluation method for the construction quality of bored cast-in-place piles according to claim 1, characterized in that, In step S4, construct a project layer judgment matrix and an index layer judgment matrix according to the construction quality evaluation index system; based on the correlation degree between the index layer monitoring data and the construction specification values calculated in step S3, calculate the subjective weight of the index layer corresponding to the construction quality evaluation index system through the project layer judgment matrix and the index layer judgment matrix, use the entropy weight method to calculate the objective weight of the index layer corresponding to the construction quality evaluation index system, and use the combined weighting method to determine the combined weight.

3. The real-time monitoring and evaluation method for the construction quality of bored cast-in-place piles according to claim 2, characterized in that, There is a fixed sleeve inside the drill pipe, and an inertial measurement unit (3) is arranged at a position of the fixed sleeve close to the drill bit; the inertial measurement unit (3) is used to measure the real-time drilling depth of the drill bit, and then obtain the drilling depth index layer.

4. The real-time monitoring and evaluation method for the construction quality of bored cast-in-place piles according to claim 2, characterized in that, A biaxial angle sensor (4) is arranged on the truss of the collar turntable of the drill pipe; the biaxial angle sensor (4) is used to measure the inclination of the collar turntable, and then obtain the drilling verticality index layer.

5. The real-time monitoring and evaluation method for the construction quality of bored cast-in-place piles according to claim 2, characterized in that, A float level gauge (7) is suspended in the mud pit or casing, a torque measurement unit (8) is arranged on the bearing of the drill bit, and an online rotational viscometer (6) is arranged at a position in the mud pit close to the mud delivery pipe; The online rotational viscometer (6) is used to monitor the viscosity of the mud and then obtain the mud viscosity index layer; When the float level gauge (7) measures that the mud level rises, the torque measurement unit (8) measures that the torque of the drill bit increases, and the online rotational viscometer (6) measures that the viscosity of the mud increases, it is determined that the drilling hole collapses, and then the drilling hole collapse index layer is obtained.

6. The real-time monitoring and evaluation method for the construction quality of bored cast-in-place piles according to claim 5, characterized in that, After hole cleaning, the drill bit rotates reversely from the bottom of the hole and the drill bit is lifted. The torque of the drill bit during the lifting process of the drill bit is monitored by the torque measurement unit (8), and the lifting height of the drill bit is recorded by the inertial measurement unit (3). When the torque becomes smaller, the height corresponding to the drill bit is determined as the sediment height, and then the sediment thickness index layer is obtained.

7. The real-time monitoring and evaluation method for the construction quality of bored cast-in-place piles according to claim 2, characterized in that, A micro-resistivity three-dimensional scanning logging tool (11) is set at the central position of the bottom of the steel reinforcement cage. The micro-resistivity three-dimensional scanning logging tool (11) is lowered together with the steel reinforcement cage. Based on the resistivity difference between the wellhead and the bottom hole wall of the wellbore, the boundary line between the mud and the wellbore wall is identified, so as to judge whether the wellbore wall is regular and obtain the quality index layer of the wellbore wall. After the concrete pouring is completed, the micro-resistivity three-dimensional scanning logging tool (11) is lifted upward. Based on the resistivity difference between the bottom and the wellhead of the wellbore wall, the uniformity of the pile body concrete pouring is judged, so as to obtain the concrete pouring uniformity index layer.

8. The real-time monitoring and evaluation method for the construction quality of bored cast-in-place piles according to claim 2, characterized in that, A GNSS locator (1) is set at the top of the construction pile frame, and a GNSS receiver (2) is set on the platform of the construction pile frame. The GNSS locator (1) monitors its relative distance from the drill pipe to determine the pile position coordinates, and then obtains the pile position coordinate index layer.

9. The real-time monitoring and evaluation method for the construction quality of bored cast-in-place piles according to claim 2, characterized in that, An insertion type tuning fork (5) is set in the mud pit; the insertion type tuning fork (5) is used to detect the mud specific gravity, and then obtain the mud specific gravity index layer.

10. The real-time monitoring and evaluation method for the construction quality of bored cast-in-place piles according to claim 2, characterized in that, A cross-shaped horizontal connecting rod is set at the top of the steel reinforcement cage, and infrared laser rangefinders (9) are set at the four ends of the cross-shaped horizontal connecting rod. An infrared laser counter (10) is set on the inner side wall of the casing, and the infrared laser counter (10) is close to the upper edge of the casing; when the steel reinforcement cage is lowered, the infrared laser counter (10) records the start of the steel reinforcement cage entering the borehole, and the infrared laser rangefinder (9) records the lowering depth and speed of the steel reinforcement cage, and then obtains the steel reinforcement cage length index layer; when the lowering depths of the steel reinforcement cage recorded by the infrared laser rangefinders (9) at the four ends are inconsistent, it is determined that the verticality of the steel reinforcement cage is unqualified, and then the steel reinforcement cage verticality index layer is obtained.

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