CN117949129A - Group column axial force detection method, device, equipment and storage medium - Google Patents
Group column axial force detection method, device, equipment and storage medium Download PDFInfo
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Abstract
The invention relates to the technical field of engineering structure detection, and discloses a method, a device, equipment and a storage medium for detecting column axial force, wherein the method comprises the following steps: classifying the group of columns to be detected according to the boundary condition of each column in the group of columns to be detected to obtain classified columns; collecting excitation response data fed back by the classification column after excitation, and determining an axial force calculation formula based on the excitation response data; and detecting axial force of a plurality of measuring points of the classified columns through an axial force calculation formula, and determining group column axial force corresponding to the group columns to be detected based on detection results. According to the invention, the axial force calculation formula is determined based on excitation response data obtained after excitation is carried out on different types of classified columns in the group column to be detected, and axial force detection is carried out according to the axial force calculation formula, so that quantification of the axial force state of the group column to be detected is realized in a nondestructive mode, and the problems that the axial force of the bottom group column of the existing building structure is difficult to quantify, in-situ damage to the column is large due to on-site axial force detection and the like are solved.
Description
Technical Field
The present invention relates to the field of engineering structure detection technologies, and in particular, to a method, an apparatus, a device, and a storage medium for detecting column axial force.
Background
With the acceleration of the urban process and the attention of people to building safety, the health condition and the stability of engineering structures become important concerns. The pillar is one of the main load bearing members in the building responsible for bearing and transmitting the upper load (including the weight of structural members such as floors, beams, and external loads) to the foundation, and the safety status of the pillar is directly related to the safety of the entire building structure. However, the columns may suffer from reduced load carrying capacity, cracking, deformation, etc. due to factors such as external environment, structural aging, design defects, or material degradation. Therefore, accurate assessment of column axial force becomes a key element in ensuring structural safety.
The current commonly used column axial force testing means is mainly a column testing method based on a strain monitoring technology, and the implementation way of the method comprises in-situ testing of the stress of the concrete column of the served structure. Firstly, chiseling a protective layer of a structure; then laying and reading the initial value of the strain gauge on the longitudinal ribs; then, an angle grinder or other grinding methods are adopted at a certain position from the upper end and the lower end of the strain gauge to reduce the area of the measured steel bar, and a strain recorder records the strain increment epsilon of the steel bar, which is obtained by reducing the area of the steel bar; repeating the steps until the measured strain increment is not changed after the two times of grinding, and taking the total strain increment as the actual stress strain value of the reinforcing steel bar at the moment to calculate the bearing shaft pressure value of the concrete column. However, the main disadvantages of the in-situ testing technology for the stress of the steel bars of the service structure include: the method can cause great damage to the components, and the method with danger can not be adopted for the components with great stress; also, because the breakage detection technology is dangerous, the breakage detection technology cannot be applied to the axial force test of a large number of group columns, and can only be applied to 1-2 concrete columns; the steel bar polishing and cutting method brings about a temperature additional effect, and an effective method for eliminating the effect is not available.
The foregoing is provided merely for the purpose of facilitating understanding of the technical solutions of the present invention and is not intended to represent an admission that the foregoing is prior art.
Disclosure of Invention
The invention mainly aims to provide a group column axial force detection method, device, equipment and storage medium, and aims to solve the technical problem that the prior art cannot be applied to a group column axial force test scene with a large number.
In order to achieve the above object, the present invention provides a method for detecting column axial force, the method comprising the steps of:
Classifying the group of columns to be detected according to the boundary conditions of all the columns in the group of columns to be detected to obtain classified columns, wherein the boundary conditions comprise column top boundary constraint conditions and boundary lateral side movement conditions of the bottom and the top of the columns;
Collecting excitation response data fed back by the classification column after excitation, and determining an axial force calculation formula based on the excitation response data;
performing axial force detection on a plurality of measuring points of the classification column through the axial force calculation formula, and determining group column axial forces corresponding to the group columns to be detected based on detection results;
The axial force calculation formula is as follows:
wherein Xc is the layout height of each acquisition measuring point, EI is the bending rigidity of the column, m is the mass of the column, N is the axial force of the column, ω is the fixed vibration frequency of the column, and C1, C2, C3 and C4 are all undetermined coefficients.
Optionally, the step of collecting excitation response data fed back by the classification column after being excited includes:
Selecting a calibration test column from the classification columns, uniformly arranging acquisition test points on the calibration test column, and installing a speed sensor on the acquisition test points;
And applying knocking excitation to the calibration test column, and collecting excitation response data fed back by the calibration test column after being knocked.
Optionally, the excitation response data includes a speed response time signal and a fixed vibration frequency, and the step of applying a knocking excitation to the calibration test column and collecting excitation response data fed back by the calibration test column after being knocked excitation includes:
After a manual hammer is adopted to apply knocking excitation at the preset height of the calibration test column, acquiring a speed response time signal of the acquisition test point through the speed sensor;
and carrying out spectrum analysis on the speed response time signal, and determining the fixed vibration frequency corresponding to the calibration test column from a spectrum analysis result based on a peak value picking method.
Optionally, the step of determining an axial force calculation formula based on the excitation response data includes:
determining the layout height, the column bending rigidity, the column mass, the column axial force, the fixed vibration frequency and the undetermined coefficient of the acquisition measuring points corresponding to the classified columns based on the excitation response data;
and determining an axial force calculation formula according to the layout height of the acquisition measuring points, the bending rigidity of the pillars, the mass of the pillars, the axial force of the pillars, the fixed vibration frequency and the undetermined coefficient.
Optionally, the step of performing axial force detection on the plurality of measuring points of the classification column through the axial force calculation formula includes:
Pasting strain gauges on the classification columns, and fully packing steel plates on part of columns of the classification columns, wherein hole sites are reserved on the steel plates;
The hole site is implanted with steel bars, so that the steel plates and the classification columns are connected to form a whole, and steel corbels are welded at the bottom end parts of the classification columns fully covered with the steel plates;
The hydraulic digital display jack and the cushion block are installed, and the cushion block is installed on the ground and used for propping the jack and the steel corbel;
and carrying out step-by-step pressure glue filling on the hydraulic digital display jack, and carrying out axial force detection on a plurality of measuring points of the classification column through the axial force calculation formula after the numerical value of the strain gauge turns.
Optionally, the step of determining the group column axial force corresponding to the group column to be detected based on the detection result includes:
And detecting the axial force of each column in the group column to be detected through an axial force calculation formula, and determining the group column axial force corresponding to the group column to be detected based on the detection result.
Optionally, the classification post includes two-sided constraint post, three-sided constraint post and four-sided constraint post, according to the boundary condition of each post in waiting to detect the crowd post to wait to detect the crowd post classifies, obtains the step of classifying post, includes:
if the boundary condition of the current column in the group of columns to be detected is two-side constraint, classifying the current column into two-side constraint columns;
If the boundary condition of the current column in the group of columns to be detected is three-side constraint, classifying the current column as a three-side constraint column;
And if the boundary condition of the current column in the group of columns to be detected is four-side constraint, classifying the current column as a four-side constraint column.
In addition, in order to achieve the above object, the present invention also provides a group column axial force detection device, including:
The group column classification module is used for classifying the group columns to be detected according to the boundary conditions of all the columns in the group columns to be detected to obtain classified columns, wherein the boundary conditions comprise column top boundary constraint conditions and boundary lateral side movement conditions of the bottom and the top of the columns;
The data acquisition module is used for acquiring excitation response data fed back by the classification column after excitation, and determining an axial force calculation formula based on the excitation response data;
and the axial force detection module is used for detecting the axial force of a plurality of measuring points of the classification column through the axial force calculation formula and determining the group column axial force corresponding to the group column to be detected based on the detection result.
In addition, in order to achieve the above object, the present invention also proposes a column axial force detection apparatus, the apparatus comprising: a memory, a processor and a group column axial force detection program stored on the memory and executable on the processor, the group column axial force detection program configured to implement the steps of the group column axial force detection method as described above.
In addition, in order to achieve the above object, the present invention also proposes a storage medium having stored thereon a group column axial force detection program which, when executed by a processor, implements the steps of the group column axial force detection method as described above.
Classifying the group of columns to be detected according to the boundary conditions of all the columns in the group of columns to be detected to obtain classified columns, wherein the boundary conditions comprise column top boundary constraint conditions and boundary lateral side movement conditions of the bottom and the top of the columns; collecting excitation response data fed back by the classification column after excitation, and determining an axial force calculation formula based on the excitation response data; and detecting axial force of a plurality of measuring points of the classification column according to the axial force calculation formula, and determining group column axial force corresponding to the group column to be detected based on a detection result. Compared with the traditional group column axial force detection method based on in-situ test of the reinforcement stress of the concrete column of the served structure, the method provided by the invention has the advantages that excitation response data is obtained after excitation is carried out on different types of classified columns in the group column to be detected, then an axial force calculation formula is determined based on the excitation response data, and finally the axial force of the group column to be detected is calculated according to the axial force calculation formula, so that the quantification of the axial force state of the group column to be detected is realized in a lossless manner, and the problems that the axial force of the group column at the bottom layer of the existing building structure is difficult to quantify, the in-situ damage to the column caused by on-site axial force detection is large and the like are solved.
Drawings
FIG. 1 is a schematic diagram of a group column axial force detection device in a hardware operating environment according to an embodiment of the present invention;
FIG. 2 is a flow chart of a first embodiment of a method for detecting axial force of a column group according to the present invention;
FIG. 3 is a flow chart of a second embodiment of the method for detecting axial force of a column group according to the present invention;
FIG. 4 is a schematic diagram of a micro-segment analysis unit of the group column axial force detection method of the present invention;
FIG. 5 is a flow chart of a third embodiment of a method for detecting axial force of a column group according to the present invention;
FIG. 6 is a graph of the lift-off and unload test of the column axial force detection method of the present invention;
FIG. 7 is a schematic diagram of column classification in the method for detecting axial force of a column in a group according to the present invention;
fig. 8 is a block diagram of a first embodiment of the group column axial force detecting device according to the present invention.
The achievement of the objects, functional features and advantages of the present invention will be further described with reference to the accompanying drawings, in conjunction with the embodiments.
Detailed Description
It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
Referring to fig. 1, fig. 1 is a schematic structural diagram of a group column axial force detection device in a hardware operation environment according to an embodiment of the present invention.
As shown in fig. 1, the group column axial force detection apparatus may include: a processor 1001, such as a central processing unit (Central Processing Unit, CPU), a communication bus 1002, a user interface 1003, a network interface 1004, a memory 1005. Wherein the communication bus 1002 is used to enable connected communication between these components. The user interface 1003 may include a Display, an input unit such as a Keyboard (Keyboard), and the optional user interface 1003 may further include a standard wired interface, a wireless interface. The network interface 1004 may optionally include a standard wired interface, a Wireless interface (e.g., a Wireless-Fidelity (Wi-Fi) interface). The Memory 1005 may be a high-speed random access Memory (Random Access Memory, RAM) or a stable nonvolatile Memory (NVM), such as a disk Memory. The memory 1005 may also optionally be a storage device separate from the processor 1001 described above.
It will be appreciated by those skilled in the art that the structure shown in fig. 1 is not limiting of the group column axis force detection apparatus and may include more or fewer components than shown, or certain components may be combined, or a different arrangement of components.
As shown in fig. 1, an operating system, a network communication module, a user interface module, and a group column axial force detection program may be included in the memory 1005 as one type of storage medium.
In the group column axial force detection device shown in fig. 1, the network interface 1004 is mainly used for data communication with a network server; the user interface 1003 is mainly used for data interaction with a user; the processor 1001 and the memory 1005 in the group column axial force detection device of the present invention may be disposed in the group column axial force detection device, where the group column axial force detection device invokes a group column axial force detection program stored in the memory 1005 through the processor 1001, and executes the group column axial force detection method provided by the embodiment of the present invention.
An embodiment of the invention provides a method for detecting axial force of a group column, referring to fig. 2, fig. 2 is a schematic flow chart of a first embodiment of the method for detecting axial force of a group column.
In this embodiment, the group column axial force detection method includes the following steps:
Step S10: classifying the group of pillars to be detected according to the boundary conditions of the pillars in the group of pillars to be detected to obtain classified pillars, wherein the boundary conditions comprise the boundary constraint condition of the top of the pillars and the lateral side movement condition of the boundaries of the bottom and the top of the pillars.
It should be noted that, the execution body of the method of this embodiment may be a terminal device having functions of axial force detection, data processing, and program running, for example, a smart phone, a computer, or the like, or may be an electronic device having the same or similar functions, for example, the group column axial force detection device described above. The present embodiment and the following embodiments will be described below with reference to a group column axial force detection device (hereinafter referred to as a detection device).
It is understood that the group of columns to be detected may be a collection of a plurality of columns. In construction, a column is a vertical support structure used to bear and transfer the weight of an overhead structure to the foundation of a building. When a building is subjected to vertical loads (e.g., gravity), these loads are transferred to the columns through horizontal members such as beams, plates, etc., and from the columns to the foundation.
It should be understood that the above boundary conditions may be the connection and constraints between the post and the surrounding structure or member. These boundary conditions have an important influence on the stress properties, deformation behavior and overall structural stability of the column. More specifically, the connection of the column to the foundation: the bottom of the column is typically fixed to the foundation of the building, and this connection needs to be able to withstand the vertical loads transmitted by the column and other possible forces (such as wind loads, seismic loads, etc.), the rigidity and stability of the foundation having a significant impact on the boundary conditions of the column. Connection of the post to the beam: in a frame structure or a hybrid structure, the connection of the columns to the beams is usually rigid, i.e. a firm connection is achieved between them by means of welding, bolting or reinforced concrete casting, etc., which connection enables the beams and columns to bear the load together, forming a unitary structure. Restraint of the post with surrounding components: in a building, the post is typically adjacent to other components (e.g., walls, floors, etc.), and interactions between these components can affect the boundary conditions of the post, e.g., constraints between the post and the walls can limit the lateral displacement of the post, thereby affecting its stressing performance. Column constraints: depending on the design requirements, the post may be subject to different constraints, such as fixed end constraints, sliding end constraints, or elastic constraints, which may affect the stress state and deformation behavior of the post.
In a specific implementation, for the bottom layer of columns, the bottoms of all columns can be considered as solid end constraints, and therefore, columns can be classified according to the constraints of the tops of the columns.
Step S20: and collecting excitation response data fed back by the classification column after being excited, and determining an axial force calculation formula based on the excitation response data.
The excitation may be a hammering excitation, for example, a hammering excitation, which is not limited in this embodiment.
It should be appreciated that the above axial force calculation formula has versatility for columns belonging to the same class. For example, the columns a and B in a certain group of columns to be detected belong to the same class of columns, and then after the axial force calculation formula of the column a is determined based on the excitation response data, the axial force calculation formula of the column a can be directly applied without determining the axial force calculation formula of the column B, so that the detection efficiency of the group column axial force detection method of the embodiment is improved.
The axial force calculation formula is as follows:
wherein Xc is the layout height of each acquisition measuring point, EI is the bending rigidity of the column, m is the mass of the column, N is the axial force of the column, ω is the fixed vibration frequency of the column, and C1, C2, C3 and C4 are all undetermined coefficients.
Step S30: and detecting axial force of a plurality of measuring points of the classification column according to the axial force calculation formula, and determining group column axial force corresponding to the group column to be detected based on a detection result.
It should be appreciated that there may be a large error in axial force detection of only a single point of the post, resulting in an inability to guarantee accuracy of the detection result. Therefore, in this embodiment, after axial force detection is performed on a plurality of measuring points of the classification column, the axial force detection results are averaged to eliminate errors as much as possible, so that the accuracy of the group column axial force corresponding to the group column to be detected is improved.
The method comprises the steps that group columns to be detected are classified according to boundary conditions of all columns in the group columns to be detected, and classified columns are obtained, wherein the boundary conditions comprise column top boundary constraint conditions and boundary lateral side movement conditions of the bottom and the top of the columns; collecting excitation response data fed back by the classification column after excitation, and determining an axial force calculation formula based on the excitation response data; and detecting axial force of a plurality of measuring points of the classification column according to the axial force calculation formula, and determining group column axial force corresponding to the group column to be detected based on a detection result. Compared with the traditional group column axial force detection method based on in-situ test of the reinforcement stress of the concrete columns of the served structure, the method of the embodiment obtains excitation response data after excitation of different types of classified columns in the group column to be detected, then determines an axial force calculation formula based on the excitation response data, and finally calculates the axial force of the group column to be detected according to the axial force calculation formula, thereby realizing quantification of the axial force state of the group column to be detected in a nondestructive mode, and solving the problems that the axial force of the group column at the bottom layer of the existing building structure is difficult to quantify, in-situ damage to the column is large in the field axial force detection and the like.
Referring to fig. 3, fig. 3 is a flow chart of a second embodiment of the group column axial force detection method according to the present invention.
Based on the first embodiment, in this embodiment, the step S20 may include:
Step S201: and selecting a calibration test column from the classification columns, uniformly distributing acquisition test points on the calibration test column, and installing a speed sensor on the acquisition test points.
It will be appreciated that the above-described speed sensor is a sensor for measuring the speed of movement of a mechanical device that is capable of converting the rotational speed through the sensor into a corresponding analog output electrical signal to assist in measuring the real-time speed of a target object. The principle of operation of a speed sensor is based on faraday's law of electromagnetic induction, i.e. the induced electromotive force generated when a conductor moves in a magnetic field, resulting in a change in current. The sensor comprises a system of a rotating gear fixed by a magnet and a sensitive coil, and when the rotating speed changes, the system generates a changing magnetic field and generates an electric signal to be output to the display device for responding.
In a specific implementation, the calibration test column can be selected from the classification columns in a random selection manner.
Step S202: and applying knocking excitation to the calibration test column, and collecting excitation response data fed back by the calibration test column after being knocked.
Further, in the present embodiment, the excitation response data includes a speed response time signal and a fixed vibration frequency, and the step S202 may include:
Step S2021: and after the manual hammer is adopted to apply knocking excitation at the preset height of the calibration test column, acquiring a speed response time signal of the acquisition test point through the speed sensor.
Step S2022: and carrying out spectrum analysis on the speed response time signal, and determining the fixed vibration frequency corresponding to the calibration test column from a spectrum analysis result based on a peak value picking method.
It should be noted that spectrum analysis is a technique or method for studying the frequency component and energy distribution of a signal. It involves the process of decomposing a signal into different frequency components, typically by representing the signal as a spectrogram or a spectral density map. The core concept of spectral analysis is to convert a signal in the time domain (time domain) into a representation in the frequency domain (frequency domain), which conversion is typically achieved using fourier transforms or variants thereof. The fourier transform can decompose the signal into a combination of sine or cosine waves of different frequencies, thereby displaying the relative intensity and phase information of the individual frequency components in the signal.
Based on the first embodiment, in this embodiment, the step S20 may include:
Step S203: and determining the layout height, the bending rigidity, the column mass, the column axial force, the fixed vibration frequency and the undetermined coefficient of the acquisition measuring points corresponding to the classified columns based on the excitation response data.
Step S204: and determining an axial force calculation formula according to the layout height of the acquisition measuring points, the bending rigidity of the pillars, the mass of the pillars, the axial force of the pillars, the fixed vibration frequency and the undetermined coefficient.
In a specific implementation, the above axial force calculation formula may be expressed as formula 1:
wherein Xc is the layout height of each acquisition measuring point, EI is the bending rigidity of the column, m is the mass of the column, N is the axial force of the column, ω is the fixed vibration frequency of the column, and C1, C2, C3 and C4 are all undetermined coefficients.
More specifically, the above-described axial force calculation formula may be determined based on the following procedure. The present calculation and analysis units include a rod unit, a beam unit, and a plate unit. Wherein the rod unit is mainly used for analyzing longitudinal vibration, the beam unit is used for analyzing transverse vibration, and the plate unit is used for analyzing transverse vibration of two-dimensional conditions. The axial force state of the column is calculated by analyzing the vibration response of the column obtained under the knocking test, and the axial force state belongs to transverse vibration analysis under the one-dimensional condition, so that the analysis is performed by adopting a beam unit. The beam units mainly comprise unit types such as Euler-Bernoulli beams, timoshenko beams and the like. Euler-Bernoulli beams are mainly used for slim beam analysis (slenderness >10 or length of the beam is 5 times greater than the beam height); the Timoshenko beam is mainly used for non-slender beam analysis, and influences of shear deformation and section moment of inertia are considered in a model. The bottom columns of conventional building structures have a large calculated height and can be analyzed as Euler-Bernoulli beams. In order to confirm this point, in this embodiment, a calculation analysis is performed by taking the structural dimensions of a residential building as an example. The first layer of a civil residential building is 5m high, the size of a bottom column is 400 multiplied by 700, the strength of the concrete of the bottom column is C50, the density is about 3000kg/m3, the elastic modulus E=3.45 multiplied by 104N/mm2, the short axis inertia moment I=b multiplied by h 3/12=3.73 multiplied by 109mm4, the short axis bending rigidity EI=3.45 multiplied by 104N/mm2 multiplied by 3.73 multiplied by 109mm4 is approximately equal to 1.287 N.mm 2, and the column mass m=4200 kg. The slenderness ratio is calculated as in formula 2:
Wherein μ is a length factor, μ=0.5 when two ends are fixedly connected; l is the length of the column, l=5 meters can be roughly taken; i is the radius of gyration, and the calculation formulas of radius of gyration in two directions are shown as formula 3 and formula 4:
According to the structural size data, the slenderness ratio of the long axis direction of the two directions of the column is 12.5, and the slenderness ratio of the short axis direction is 21.7. The ratio of the length of the columns in the two axial directions is greater than 10, so that the analysis can be carried out by using an Euler-Bernoulli beam unit.
The system degree of freedom type comprises a single degree of freedom, multiple degrees of freedom and a continuous system. And respectively carrying out vibration response analysis on each column, and taking the fitting degree with the actual situation into consideration, wherein a continuous system is adopted for analysis. The column member is equivalent to an Euler-Bernoulli beam unit, and the load condition of the beam unit is as follows: the beam end is subjected to column axial force N, the cross section is subjected to hammering load P (x, t), the bending rigidity of the cross section is constant EI, and the mass of the cross section is constant m. The micro-segment is taken from the position x of the end face to be analyzed, as shown in a schematic diagram of a micro-segment analysis unit of the group column axial force detection method shown in fig. 4, Q (x, t) is the shearing force at the position x of the moment t, M (x, t) is the bending moment at the position x of the moment t, and dx is the length of the micro-element body. At the x+dx position, the vertical equilibrium condition can be expressed by equation 5:
Wherein, Is the vertical deformation of the beam unit micro-element body,/>Second-order partial differentiation of vertical deformation of beam unit micro-element body,/>Is the first order partial derivative of shear force,/>As inertial force, the formula 6 is obtained after finishing:
taking moment from the center point of the right section of the micro-segment according to the moment balance condition, and obtaining the formula 7:
The higher order small amount is omitted and, The first-order partial differentiation of the vertical deformation of the beam unit micro element body can be obtained after finishing, and the formula 8 is obtained:
bringing equation 8 into equation 6 yields equation 9:
According to the theory of elementary deformation of the beam, the relationship between the bending moment and the curvature of the beam can be expressed as formula 10:
bringing equation 10 into equation 9 yields equation 11:
Solving based on the separation variable method, the general solution of equation 11 has the form of equation 12 as follows:
u(x,t)=y(x)T(t)
where T (T) =sin (ωt+Φ), T (T) is a vibration time-course function, ω is a fixed vibration frequency of the beam, and y (x) is a modal function.
Based on the above formula, formula 13 can be obtained:
simplifying equation 13 yields equation 14:
Equation 14 belongs to a fourth-order linear non-homogeneous differential equation, and first, its homogeneous equation solution is solved, as shown in equation 15:
The characteristic equation corresponding to equation 15 can be expressed as equation 16:
where a is the deflection function of the beam unit infinitesimal, p and q are the two constant coefficients of equation 16, p=n/EI, q=mω 2/EI, respectively.
Solving equation 16 yields equation 17:
and/> Based on the above equations, two characteristic roots of equation 16, respectively, equation 18 and equation 19 can be derived:
Wherein C 1、C2、C3、C4 is a coefficient to be determined, which can be obtained according to different constraint conditions and boundary conditions.
Bringing equation 18 into equation 14 yields equation 20:
wherein P (x, t) is a hammering load, having the form of formula 21:
Wherein C is the equivalent hammering force of the load, x 0 is the hammering excitation application height, and t 0 is the load application time.
Taking equation 20 into equation 12, the beam's lateral vibration equations can be found as equation 22, equation 23, and equation 24:
v max (x) is the maximum value of the vibration velocity at the x height position, as can be seen from equation 24, for a certain measurement point at a fixed height of a specific column, the values of x=x c, EI and m are fixed, ω can be determined by first performing a preliminary test, so that the maximum value of the velocity response only includes the column axial force N to be solved, as shown in equation 25:
Therefore, the maximum value v max of the velocity response has a clear functional relation with the column axial force N, and when the undetermined coefficients C 1、C2、C3 and C 4 are determined, the numerical relation between the column axial force N and the maximum value v max of the velocity response is unique, and the column axial force N can be solved by the actually measured v max. However, since the actual boundary conditions of the structure are difficult to determine ideally, the undetermined coefficients C 1、C2、C3 and C 4 are often difficult to solve, and thus the undetermined coefficients C 1、C2、C3 and C 4 can be determined here in combination with the lift-off unloading method, and finally an explicit formula of the column axis force N is obtained.
According to the embodiment, calibration test columns are selected from the classification columns, acquisition test points are uniformly distributed on the calibration test columns, and a speed sensor is arranged on each acquisition test point; after a manual hammer is adopted to apply knocking excitation at the preset height of the calibration test column, acquiring a speed response time signal of the acquisition test point through the speed sensor; performing spectrum analysis on the speed response time signal, and determining a fixed vibration frequency corresponding to the calibration test column from a spectrum analysis result based on a peak picking method; determining the layout height, the column bending rigidity, the column mass, the column axial force, the fixed vibration frequency and the undetermined coefficient of the acquisition measuring points corresponding to the classified columns based on the excitation response data; and determining an axial force calculation formula according to the layout height of the acquisition measuring points, the bending rigidity of the pillars, the mass of the pillars, the axial force of the pillars, the fixed vibration frequency and the undetermined coefficient. Compared with the traditional group column axial force detection method, the method of the embodiment determines an axial force calculation formula by classifying the layout height, the column bending rigidity, the column mass, the column axial force, the fixed vibration frequency and the undetermined coefficient of the acquisition measuring points corresponding to the columns, thereby realizing the nondestructive test of qualitatively and quantitatively obtaining the group column axial force of the bottom layer of the structure.
Referring to fig. 5, fig. 5 is a flow chart of a third embodiment of the group column axial force detection method according to the present invention.
Based on the above embodiments, in this embodiment, the step S30 may include:
Step S301: and pasting a strain gauge on the classification column, fully wrapping a steel plate on part of columns of the classification column, and reserving a hole site on the steel plate.
It is understood that the strain gauge is an element for measuring strain, which is constituted by a sensitive grating or the like. It is a passive sensor that converts mechanical displacement into a change in resistance. The working principle of the strain gauge is based on the strain effect, namely, when a conductor or a semiconductor material is mechanically deformed under the action of external force, the resistance value of the strain gauge is correspondingly changed, and the change can be used for measuring the strain or the external force. The structure of the strain gauge typically includes a sensitive gate, a gauge insulating substrate, and a cover layer. The sensitive grating is a core part of the strain gauge and is made of thin metal foil and is used for sensing mechanical strain and generating resistance change. The strain gage insulating substrate provides support and isolation for the sensitive grating to prevent interference with the electrical signal. The cover layer is used for protecting the sensitive grid and the insulating substrate so as to improve the durability and the stability of the strain gage.
Step S302: and (3) carrying out steel bar implantation on the hole site, so that the steel plate and the classification column are connected to form a whole, and carrying out steel corbel welding on the bottom end part of the classification column full-packed steel plate.
Step S303: and the hydraulic digital display jack and the cushion block are installed, and the cushion block is installed on the ground and is used for propping the jack and the steel corbel.
Step S304: and carrying out step-by-step pressure glue filling on the hydraulic digital display jack, and carrying out axial force detection on a plurality of measuring points of the classification column through the axial force calculation formula after the numerical value of the strain gauge turns.
Step S305: and detecting the axial force of each column in the group column to be detected through an axial force calculation formula, and determining the group column axial force corresponding to the group column to be detected based on the detection result.
In specific implementation, reference may be made to fig. 6, and fig. 6 is a lifting and unloading test chart of the group column axial force detection method according to the present invention. Fully wrapping the steel plate and performing reinforcement implantation on the steel plate and the column, so that firm connection is formed between the outer wrapping steel plate and the test column; the steel corbels and the outer-covered steel plates are welded to form a whole; the hydraulic digital display jack realizes the application of the lifting acting force of the column by controlling hydraulic pressure; the jacking force applied by the jack acts on the steel corbel, and the jacking force is transmitted to the outer-coating steel plate through the shearing force between the steel corbel and the outer-coating steel plate; the force is transmitted to the test column by the steel-embedded bars between the steel-encased plates and the column, so that the column jacking force is applied.
Based on the above embodiments, in this embodiment, the step S10 may include:
step S101: and if the boundary condition of the current column in the group of columns to be detected is two-side constraint, classifying the current column as a two-side constraint column.
Step S102: and if the boundary condition of the current column in the group of columns to be detected is three-side constraint, classifying the current column as a three-side constraint column.
Step S103: and if the boundary condition of the current column in the group of columns to be detected is four-side constraint, classifying the current column as a four-side constraint column.
In a specific implementation, for the bottom layer of columns, the bottoms of all columns can be considered as solid end constraints, and therefore, columns can be classified according to the constraints of the tops of the columns. For example, referring to fig. 7, fig. 7 is a column classification schematic diagram of the group column axial force detection method according to the present invention, for an ideal new building, the lateral sides of the two ends of the bottom column of the structure can be regarded as 0, and the columns in fig. 7 can be classified into three types: the white pillars in the middle of the structure can be classified as four-sided constraint pillars, the peripheral gray pillars can be classified as three-sided constraint pillars, and the black pillars at the four corners are classified as two-sided constraint pillars. Column axial force tests were performed separately for different classes of columns.
In the embodiment, strain gauges are stuck on the classification columns, and part of columns of the classification columns are fully covered with steel plates, wherein hole sites are reserved on the steel plates; the hole site is implanted with steel bars, so that the steel plates and the classification columns are connected to form a whole, and steel corbels are welded at the bottom end parts of the classification columns fully covered with the steel plates; the hydraulic digital display jack and the cushion block are installed, and the cushion block is installed on the ground and used for propping the jack and the steel corbel; performing progressive pressure glue filling on the hydraulic digital display jack, and performing axial force detection on a plurality of measuring points of the classification column through the axial force calculation formula after the numerical value of the strain gauge turns; performing axial force detection on each column in the group column to be detected through an axial force calculation formula, and determining group column axial force corresponding to the group column to be detected based on a detection result; if the boundary condition of the current column in the group of columns to be detected is two-side constraint, classifying the current column into two-side constraint columns; if the boundary condition of the current column in the group of columns to be detected is three-side constraint, classifying the current column as a three-side constraint column; and if the boundary condition of the current column in the group of columns to be detected is four-side constraint, classifying the current column as a four-side constraint column. Compared with the traditional group column axial force detection method, the method in the embodiment realizes quantification of the axial force state of the column at the bottom layer of the structure in a nondestructive mode, and solves the problems that the axial force of the group column at the bottom layer of the existing building structure is difficult to quantify, in-situ damage to the column is large due to in-situ axial force detection and the like.
In addition, the embodiment of the invention also provides a storage medium, wherein a group column axial force detection program is stored on the storage medium, and the group column axial force detection program realizes the steps of the group column axial force detection method when being executed by a processor.
Referring to fig. 8, fig. 8 is a block diagram illustrating a first embodiment of a group column axial force detecting device according to the present invention.
As shown in fig. 8, the group column axial force detection device provided by the embodiment of the invention includes:
The group column classification module 801 is configured to classify the group columns to be detected according to boundary conditions of each column in the group columns to be detected, so as to obtain classified columns, where the boundary conditions include a column top boundary constraint condition and a boundary lateral side movement condition of the bottom and top of the column;
The data acquisition module 802 is used for acquiring excitation response data fed back by the classification column after being excited, and determining an axial force calculation formula based on the excitation response data; the axial force calculation formula is as follows:
wherein Xc is the layout height of each acquisition measuring point, EI is the bending rigidity of the column, m is the mass of the column, N is the axial force of the column, ω is the fixed vibration frequency of the column, and C1, C2, C3 and C4 are all undetermined coefficients.
And the axial force detection module 803 is configured to detect axial forces of a plurality of measurement points of the classification column according to the axial force calculation formula, and determine group column axial forces corresponding to the group column to be detected based on a detection result.
The method comprises the steps that group columns to be detected are classified according to boundary conditions of all columns in the group columns to be detected, and classified columns are obtained, wherein the boundary conditions comprise column top boundary constraint conditions and boundary lateral side movement conditions of the bottom and the top of the columns; collecting excitation response data fed back by the classification column after excitation, and determining an axial force calculation formula based on the excitation response data; and detecting axial force of a plurality of measuring points of the classification column according to the axial force calculation formula, and determining group column axial force corresponding to the group column to be detected based on a detection result. Compared with the traditional group column axial force detection method based on in-situ test of the reinforcement stress of the concrete columns of the served structure, the method of the embodiment obtains excitation response data after excitation of different types of classified columns in the group column to be detected, then determines an axial force calculation formula based on the excitation response data, and finally calculates the axial force of the group column to be detected according to the axial force calculation formula, thereby realizing quantification of the axial force state of the group column to be detected in a nondestructive mode, and solving the problems that the axial force of the group column at the bottom layer of the existing building structure is difficult to quantify, in-situ damage to the column is large in the field axial force detection and the like.
Based on the first embodiment of the group column axial force detection device of the present invention, a second embodiment of the group column axial force detection device of the present invention is provided.
In this embodiment, the data acquisition module 802 is further configured to select a calibration test column from the classification columns, and uniformly arrange acquisition test points on the calibration test column, where a speed sensor is installed on the acquisition test points; and applying knocking excitation to the calibration test column, and collecting excitation response data fed back by the calibration test column after being knocked.
Further, the data acquisition module 802 is further configured to acquire, by using the speed sensor, a speed response time signal of the acquisition test point after the tapping excitation is applied to the preset height of the calibration test column by using the manual hammer; and carrying out spectrum analysis on the speed response time signal, and determining the fixed vibration frequency corresponding to the calibration test column from a spectrum analysis result based on a peak value picking method.
Further, the data acquisition module 802 is further configured to determine, based on the excitation response data, a layout height of an acquisition measurement point corresponding to the classified pillar, a pillar bending stiffness, a pillar mass, a pillar axial force, a fixed vibration frequency, and a undetermined coefficient; and determining an axial force calculation formula according to the layout height of the acquisition measuring points, the bending rigidity of the pillars, the mass of the pillars, the axial force of the pillars, the fixed vibration frequency and the undetermined coefficient.
Further, the axial force detection module 803 is further configured to paste a strain gauge on the classification column and fully pack a part of columns of the classification column with a steel plate, where a hole site is reserved on the steel plate; the hole site is implanted with steel bars, so that the steel plates and the classification columns are connected to form a whole, and steel corbels are welded at the bottom end parts of the classification columns fully covered with the steel plates; the hydraulic digital display jack and the cushion block are installed, and the cushion block is installed on the ground and used for propping the jack and the steel corbel; and carrying out step-by-step pressure glue filling on the hydraulic digital display jack, and carrying out axial force detection on a plurality of measuring points of the classification column through the axial force calculation formula after the numerical value of the strain gauge turns.
Further, the axial force detection module 803 is further configured to perform axial force detection on each column in the group column to be detected according to an axial force calculation formula, and determine a group column axial force corresponding to the group column to be detected based on a detection result.
Further, the group column classification module 801 is further configured to classify the current column as a two-sided constraint column if the boundary condition of the current column in the group column to be detected is a two-sided constraint column; if the boundary condition of the current column in the group of columns to be detected is three-side constraint, classifying the current column as a three-side constraint column; and if the boundary condition of the current column in the group of columns to be detected is four-side constraint, classifying the current column as a four-side constraint column.
Other embodiments or specific implementation manners of the group column axial force detection device of the present invention may refer to the above method embodiments, and are not described herein.
It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.
The foregoing embodiment numbers of the present invention are merely for the purpose of description, and do not represent the advantages or disadvantages of the embodiments.
From the above description of embodiments, it will be clear to a person skilled in the art that the above embodiment method may be implemented by means of software plus a necessary general hardware platform, but may of course also be implemented by means of hardware, but in many cases the former is a preferred embodiment. Based on this understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a storage medium (e.g. read-only memory/random-access memory, magnetic disk, optical disk), comprising instructions for causing a terminal device (which may be a mobile phone, a computer, a server, or a network device, etc.) to perform the method according to the embodiments of the present invention.
The foregoing description is only of the preferred embodiments of the present invention, and is not intended to limit the scope of the invention, but rather is intended to cover any equivalents of the structures or equivalent processes disclosed herein or in the alternative, which may be employed directly or indirectly in other related arts.
Claims (10)
1. A method for detecting axial force of a population, the method comprising the steps of:
Classifying the group of columns to be detected according to the boundary conditions of all the columns in the group of columns to be detected to obtain classified columns, wherein the boundary conditions comprise column top boundary constraint conditions and boundary lateral side movement conditions of the bottom and the top of the columns;
Collecting excitation response data fed back by the classification column after excitation, and determining an axial force calculation formula based on the excitation response data;
performing axial force detection on a plurality of measuring points of the classification column through the axial force calculation formula, and determining group column axial forces corresponding to the group columns to be detected based on detection results;
The axial force calculation formula is as follows:
wherein Xc is the layout height of each acquisition measuring point, EI is the bending rigidity of the column, m is the mass of the column, N is the axial force of the column, ω is the fixed vibration frequency of the column, and C1, C2, C3 and C4 are all undetermined coefficients.
2. The method of claim 1, wherein the step of collecting excitation response data fed back by the classification column after excitation comprises:
Selecting a calibration test column from the classification columns, uniformly arranging acquisition test points on the calibration test column, and installing a speed sensor on the acquisition test points;
And applying knocking excitation to the calibration test column, and collecting excitation response data fed back by the calibration test column after being knocked.
3. The method of group column axial force detection of claim 2, wherein the excitation response data includes a velocity response time signal and a fixed vibration frequency, the step of applying a tapping excitation to the calibration test column and collecting excitation response data fed back by the calibration test column after receiving the tapping excitation, comprising:
After a manual hammer is adopted to apply knocking excitation at the preset height of the calibration test column, acquiring a speed response time signal of the acquisition test point through the speed sensor;
and carrying out spectrum analysis on the speed response time signal, and determining the fixed vibration frequency corresponding to the calibration test column from a spectrum analysis result based on a peak value picking method.
4. The group column axial force detection method according to claim 1, wherein the step of determining an axial force calculation formula based on the excitation response data includes:
determining the layout height, the column bending rigidity, the column mass, the column axial force, the fixed vibration frequency and the undetermined coefficient of the acquisition measuring points corresponding to the classified columns based on the excitation response data;
and determining an axial force calculation formula according to the layout height of the acquisition measuring points, the bending rigidity of the pillars, the mass of the pillars, the axial force of the pillars, the fixed vibration frequency and the undetermined coefficient.
5. The method for detecting axial force of group column according to claim 1, wherein the step of detecting axial force of a plurality of measuring points of the classification column by the axial force calculation formula comprises:
Pasting strain gauges on the classification columns, and fully packing steel plates on part of columns of the classification columns, wherein hole sites are reserved on the steel plates;
The hole site is implanted with steel bars, so that the steel plates and the classification columns are connected to form a whole, and steel corbels are welded at the bottom end parts of the classification columns fully covered with the steel plates;
The hydraulic digital display jack and the cushion block are installed, and the cushion block is installed on the ground and used for propping the jack and the steel corbel;
and carrying out step-by-step pressure glue filling on the hydraulic digital display jack, and carrying out axial force detection on a plurality of measuring points of the classification column through the axial force calculation formula after the numerical value of the strain gauge turns.
6. The group column axial force detection method according to claim 1, wherein the step of determining the group column axial force corresponding to the group column to be detected based on the detection result comprises:
And detecting the axial force of each column in the group column to be detected through an axial force calculation formula, and determining the group column axial force corresponding to the group column to be detected based on the detection result.
7. The method for detecting axial force of group columns according to claim 1, wherein the classification columns include two-side constraint columns, three-side constraint columns and four-side constraint columns, and the step of classifying the group columns to be detected according to boundary conditions of each column in the group columns to be detected to obtain classification columns includes:
if the boundary condition of the current column in the group of columns to be detected is two-side constraint, classifying the current column into two-side constraint columns;
If the boundary condition of the current column in the group of columns to be detected is three-side constraint, classifying the current column as a three-side constraint column;
And if the boundary condition of the current column in the group of columns to be detected is four-side constraint, classifying the current column as a four-side constraint column.
8. Group post axial force detection device, its characterized in that, group post axial force detection device includes:
The group column classification module is used for classifying the group columns to be detected according to the boundary conditions of all the columns in the group columns to be detected to obtain classified columns, wherein the boundary conditions comprise column top boundary constraint conditions and boundary lateral side movement conditions of the bottom and the top of the columns;
The data acquisition module is used for acquiring excitation response data fed back by the classification column after excitation, and determining an axial force calculation formula based on the excitation response data;
the axial force detection module is used for detecting axial force of a plurality of measuring points of the classification column through the axial force calculation formula and determining group column axial force corresponding to the group column to be detected based on a detection result;
The axial force calculation formula is as follows:
wherein Xc is the layout height of each acquisition measuring point, EI is the bending rigidity of the column, m is the mass of the column, N is the axial force of the column, ω is the fixed vibration frequency of the column, and C1, C2, C3 and C4 are all undetermined coefficients.
9. A population column axial force detection apparatus, the apparatus comprising: a memory, a processor and a group column axial force detection program stored on the memory and executable on the processor, the group column axial force detection program configured to implement the steps of the group column axial force detection method of any one of claims 1 to 7.
10. A storage medium, wherein a group column axial force detection program is stored on the storage medium, and wherein the group column axial force detection program, when executed by a processor, implements the steps of the group column axial force detection method according to any one of claims 1 to 7.
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