Design and construction method of building masonry based on BIM (Building Information Modeling)

Abstract

The invention discloses a BIM-based building masonry design and construction method, and relates to the technical field of buildings, and the method comprises the steps: building a BIM model of a building according to a BIM technology, determining the size of a brick body and the thickness of a mortar joint, and calculating the overall masonry deviation coefficient of a masonry part; collecting a complete image of the actual masonry part by using a camera, extracting mortar joints of the actual masonry part, calculating a deviation coefficient of a transverse mortar joint and a deviation coefficient of a longitudinal mortar joint, and further calculating a masonry mortar joint deviation index; measuring points are randomly selected at the masonry part, the same force is used for knocking at the measuring points, a recording device is used for collecting knocking audios, and a knocking audio evaluation index and masonry audio variance are calculated; and obtaining a masonry overall deviation coefficient, a masonry mortar joint deviation index and a masonry audio variance of the masonry part, calculating a masonry comprehensive evaluation index, and sending out an early warning of unqualified masonry quality. And the construction team is helped to optimize the construction plan.

Description

Technical Field

[0001] The present invention relates to the field of building technology, and in particular to a design and construction method for building masonry based on BIM. Background Art

[0002] In the construction industry, masonry engineering is an important part of the construction process and is directly related to the stability and safety of the building structure. Traditional masonry construction methods often rely on the experience and manual operation of construction workers, and there are problems such as low construction accuracy, low efficiency, and material waste. With the continuous development of building information technology, technology based on Building Information Modeling (BIM) has gradually been widely used in the construction field. BIM technology is a digital building design and construction management method that integrates the entire life cycle information of the building project from design, construction to operation and maintenance by creating a virtual building model. Using BIM technology, building information can be digitized, integrated, and visualized, thereby improving construction efficiency and quality and reducing project costs.

[0003] In the Chinese invention application with application publication number CN113435757A, a design and construction method of building masonry based on BIM is disclosed, including S1, reading design drawings, obtaining spatial data information of the building to be constructed, and establishing a BIM preset model; S2, extracting the model masonry position, the size of the preset brick body, and the mortar joint thickness between two adjacent preset brick bodies in the BIM preset model to form a main database; S3, real-time collection of construction masonry position, masonry brick body size, and the mortar joint thickness between two adjacent masonry brick bodies to form a measured database; S4, comparing the measured database and the main database. The design and construction method of building masonry based on BIM provided by the present invention strengthens the integration of construction information and design information, improves the networking effect of the masonry process and the control of masonry construction; strengthens the control of construction quality, thereby improving the design and construction work efficiency, effectively reducing rework, improving construction quality and reducing material waste.

[0004] In the above invention application, the construction masonry position, masonry brick size and mortar joint thickness between two adjacent masonry bricks are collected in real time, and the measured database and the main database are compared to improve the networking effect of the masonry process and the control of masonry construction. However, the real-time collection process is completed by a collection robot entering the construction site. A laser scanning device is set on the collection robot, and the collection robot is connected to the computer's GIS system for communication. Then the information is transmitted to the BIM model in the computer through the laser scanning device and the GIS system, so that the preset model information in the BIM model and the information on the construction site are matched, which makes the masonry monitoring cost high, and because the construction site environment is complex and changeable, such as dust, vibration, temperature changes, etc., it may affect the accuracy and stability of the monitoring equipment. In addition, the construction space is limited and may not be able to accommodate all the necessary monitoring equipment.

[0005] To this end, the present invention provides a design and construction method for building masonry based on BIM. Summary of the invention

[0006] 1. Technical issues to be resolved In view of the deficiencies in the prior art, the present invention provides a design and construction method for building masonry based on BIM. The present invention obtains the overall deviation coefficient Qzp, the mortar joint deviation index Fp and the audio variance Cf of the masonry part, calculates the comprehensive evaluation index Qp of the masonry, and issues an early warning of unqualified masonry quality. The masonry quality can be quantitatively evaluated, avoiding the subjectivity and uncertainty of traditional visual inspection or empirical judgment. The early warning of unqualified masonry quality can be automatically issued, and relevant personnel can be promptly reminded to pay attention and take corresponding measures, and the unqualified parts can be promptly rectified, which is helpful for the construction team to optimize the construction plan, reasonably arrange resources, and improve construction efficiency, thereby solving the technical problems recorded in the background technology.

[0007] (II) Technical solution To achieve the above objectives, the present invention is implemented through the following technical solutions: A design and construction method of building masonry based on BIM, comprising the following steps: Obtain the architectural design drawings, establish the BIM model of the building based on BIM technology, determine the brick size and mortar joint thickness that meet the standards, use a laser rangefinder to measure the actual size of the actual masonry part, and calculate the overall deviation coefficient Qzp of the masonry part; Use the camera to capture the complete image of the actual masonry part, extract the mortar joints of the actual masonry part, and obtain the thickness of all horizontal mortar joints , Offset Angle and the thickness of all longitudinal mortar joints and offset angle , calculate the deviation coefficient Fhp of the transverse mortar joint and the deviation coefficient Fzp of the longitudinal mortar joint, and further calculate the masonry mortar joint deviation index Fp; Randomly select measurement points on the masonry part, use the same force to knock at the measurement points, use recording equipment to collect knocking audio, and calculate the knocking audio evaluation index Yj and masonry audio variance Cf; The overall deviation coefficient Qzp, mortar joint deviation index Fp and audio variance Cf of the masonry part are obtained, the comprehensive evaluation index Qp of the masonry is calculated, and an early warning of unqualified masonry quality is issued.

[0008] Furthermore, the architectural design drawings are obtained, and a BIM model of the building is established based on BIM technology. The key dimensions of the masonry part, including the thickness, height, length of the masonry part and the size requirements of special parts, are extracted from the BIM model. The brick size that is closest to the thickness of the masonry part and meets the standards is selected, and the mortar joint thickness is adjusted to match the size of the masonry part. The brick size and mortar joint thickness that meet the standards are determined and recorded as the ideal transverse mortar joint thickness Lh and the ideal longitudinal mortar joint thickness Lz.

[0009] Commonly used standard brick sizes include 240mm×115mm×53mm (length×width×thickness), etc. The thickness of the mortar joints is generally controlled between 8 and 12mm. The specific value can be adjusted according to actual conditions and design requirements.

[0010] Furthermore, a laser rangefinder is used to measure the actual dimensions of the actual masonry part, including the thickness Hd, height Gd, length Cd of the masonry part and the thickness Thd, height Tgd, length Tcd of the special part, and the overall deviation coefficient Qzp of the masonry part is calculated:

[0011] in, , and are the designed thickness, height and length of the masonry part, , and They are the designed thickness, height and length of special parts of the masonry.

[0012] Furthermore, a camera is used to capture a complete image of the actual masonry part, and the image scale is determined based on the actual size of the actual masonry part measured by a laser rangefinder, and the image size is aligned with the actual size.

[0013] Furthermore, the mortar joints of the actual masonry part are extracted from the complete image of the actual masonry part based on the crack detection technology in image processing, and the transverse mortar joints and longitudinal mortar joints are identified according to the direction and position information of the cracks. The measurement tools in the image processing software are used to extract the sizes (i.e., length*width) and offset angles of the transverse mortar joints and longitudinal mortar joints, and the edge with the smaller size is selected and recorded as the thickness of the transverse mortar joint or the longitudinal mortar joint.

[0014] Among them, the offset angle of the horizontal mortar joint is based on the horizontal line, and the offset angle of the longitudinal mortar joint is based on the vertical line.

[0015] Further, obtain the thickness of all horizontal mortar joints , Offset Angle and the thickness of all longitudinal mortar joints and offset angle , calculate the deviation coefficient Fhp of the transverse mortar joint and the deviation coefficient Fzp of the longitudinal mortar joint:

[0016] in, i Indicates the number of all transverse mortar joints in the actual masonry part. i =1, 2, …, n , n is the total number of transverse mortar joints.

[0017] Furthermore, the deviation coefficient Fhp of the transverse mortar joint and the deviation coefficient Fzp of the longitudinal mortar joint are obtained, and the masonry mortar joint deviation index Fp is calculated:

[0018] The calculation formula for the corresponding masonry joint deviation index Fp is as above.

[0019] Furthermore, randomly select measurement points on the masonry part, use the same force to knock on the measurement points, use a recording device to collect the knocking audio, use Fourier transform to convert the time domain signal into a frequency domain signal, and divide the frequency range into a equal parts, each of which has a width of , get the amplitude in each frequency bin , and the number of frequency points within the frequency division , calculate the percussion audio evaluation index Yj:

[0020] Among them, k represents the sequence number corresponding to each frequency equal part, , a is the total number of frequency bins.

[0021] Furthermore, the percussion audio evaluation index Yj of all measurement points is obtained, and the masonry audio variance Cf is calculated:

[0022] Where j represents the sequential number of all measurement points in the masonry part, , m is the total number of measurement points.

[0023] Furthermore, the masonry overall deviation coefficient Qzp, masonry mortar joint deviation index Fp and masonry audio variance Cf of the masonry part are obtained, and the masonry comprehensive evaluation index Qp is calculated:

[0024] in, Indicates the maximum value of the overall deviation coefficient of historical masonry, Indicates the minimum value of the overall deviation coefficient of historical masonry, Indicates the maximum value of the historical masonry joint deviation index, Indicates the minimum value of the historical masonry joint deviation index, represents the maximum value of the historical masonry audio variance, Indicates the minimum value of historical masonry audio variance.

[0025] Furthermore, when the masonry comprehensive evaluation index Qp is greater than When the masonry quality is not up to standard, an early warning is issued. represents the mean value of the comprehensive evaluation index of historical masonry, Represents the variance of the comprehensive evaluation index of historical masonry.

[0026] (III) Beneficial effects The present invention provides a design and construction method for building masonry based on BIM, which has the following beneficial effects: 1. Obtain the architectural design drawings, establish the BIM model of the building based on BIM technology, determine the brick size and mortar joint thickness that meet the standards, record it as the ideal mortar joint thickness Lh, and use a laser rangefinder to measure the actual size of the actual masonry part, calculate the overall deviation coefficient Qzp of the masonry part, and accurately plan the arrangement of the bricks and the thickness of the mortar joints to ensure that the pre-construction planning is highly consistent with the actual construction, accurately calculate the quantity and specifications of the required materials, and optimize material procurement and inventory management.

[0027] 2. Use the camera to capture the complete image of the actual masonry part, extract the mortar joints of the actual masonry part, and obtain the thickness of all horizontal mortar joints , Offset Angle and the thickness of all longitudinal mortar joints and offset angle , calculate the deviation coefficient Fhp of the transverse mortar joint and the deviation coefficient Fzp of the longitudinal mortar joint, and further calculate the masonry mortar joint deviation index Fp, which can intuitively understand the uniformity and consistency of the mortar joints during the masonry process, taking into account the overall deviation of the transverse and longitudinal mortar joints, and providing a scientific basis for the comprehensive evaluation of the masonry quality.

[0028] 3. Randomly select measurement points on the masonry part, knock at the measurement points with the same force, use a recording device to collect the knocking audio, calculate the knocking audio evaluation index Yj and the masonry audio variance Cf, and analyze the knocking sound differences between different measurement points, so as to accurately locate the problem areas of masonry quality. For example, a large variance may mean that there are problems with the fullness or flatness of the mortar joints in certain areas. It can objectively reflect the quality of masonry and provide a scientific basis for acceptance work.

[0029] 4. Obtain the overall deviation coefficient Qzp, mortar joint deviation index Fp and audio variance Cf of the masonry part, calculate the comprehensive evaluation index Qp of the masonry, and issue an early warning of unqualified masonry quality. This can quantitatively evaluate the quality of masonry and avoid the subjectivity and uncertainty of traditional visual inspection or empirical judgment. It can automatically issue an early warning of unqualified masonry quality, promptly remind relevant personnel to pay attention and take corresponding measures, and promptly rectify the unqualified parts, which will help the construction team optimize the construction plan, arrange resources reasonably, and improve construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The present invention is a schematic diagram of a flow chart of a design and construction method for building masonry based on BIM. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] See also Figure 1 The present invention provides a design and construction method for building masonry based on BIM, comprising the following steps: Step 1: Obtain the architectural design drawings, establish the BIM model of the building based on BIM technology, determine the brick size and mortar joint thickness that meet the standards, use a laser rangefinder to measure the actual size of the actual masonry part, and calculate the overall deviation coefficient Qzp of the masonry part.

[0033] The step 1 includes the following contents: Step 101, obtain the building design drawings, establish the BIM model of the building based on BIM technology, extract the key dimensions of the masonry part from the BIM model, including the thickness, height, length of the masonry part and the size requirements of special parts, select the brick size that is closest to the thickness of the masonry part and meets the standard, and adjust the mortar joint thickness to match the size of the masonry part, determine the brick size and mortar joint thickness that meet the standard, and record them as the ideal transverse mortar joint thickness Lh and the ideal longitudinal mortar joint thickness Lz.

[0034] Commonly used standard brick sizes include 240mm×115mm×53mm (length×width×thickness), etc. The thickness of the mortar joints is generally controlled between 8 and 12mm. The specific value can be adjusted according to actual conditions and design requirements.

[0035] Step 102: Use a laser rangefinder to measure the actual size of the actual masonry part, including the thickness Hd, height Gd, length Cd of the masonry part and the thickness Thd, height Tgd, length Tcd of the special part, and calculate the overall deviation coefficient Qzp of the masonry part:

[0036] in, , and are the designed thickness, height and length of the masonry part, , and They are the designed thickness, height and length of special parts of the masonry.

[0037] When using, combine the contents in steps 101 and 102: Obtain the architectural design drawings, establish the BIM model of the building based on BIM technology, determine the brick size and mortar joint thickness that meet the standards, use a laser rangefinder to measure the actual size of the actual masonry part, and calculate the overall deviation coefficient Qzp of the masonry part. This can accurately plan the arrangement of bricks and the thickness of mortar joints, ensure that the pre-construction planning is highly consistent with the actual construction, accurately calculate the quantity and specifications of the required materials, and optimize material procurement and inventory management.

[0038] Step 2: Use the camera to capture the complete image of the actual masonry part, extract the mortar joints of the actual masonry part, and obtain the thickness of all horizontal mortar joints , Offset Angle and the thickness of all longitudinal mortar joints and offset angle , calculate the deviation coefficient Fhp of the transverse mortar joint and the deviation coefficient Fzp of the longitudinal mortar joint, and further calculate the masonry mortar joint deviation index Fp.

[0039] The step 2 includes the following contents: Step 201: Use a camera to capture a complete image of the actual masonry part, determine the image scale based on the actual size of the actual masonry part measured by a laser rangefinder, and align the image size with the actual size.

[0040] Step 202: extract the mortar joints of the actual masonry part from the complete image of the actual masonry part based on the crack detection technology in image processing, identify the transverse mortar joints and the longitudinal mortar joints based on the direction and position information of the cracks, and use the measurement tools in the image processing software to extract the size (i.e., length*width) and offset angle of the transverse mortar joints and the longitudinal mortar joints, and select the side with the smaller size as the thickness of the transverse mortar joint or the longitudinal mortar joint.

[0041] Among them, the offset angle of the horizontal mortar joint is based on the horizontal line, and the offset angle of the longitudinal mortar joint is based on the vertical line.

[0042] Step 203: Obtain the thickness of all horizontal mortar joints , Offset Angle and the thickness of all longitudinal mortar joints and offset angle , calculate the deviation coefficient Fhp of the transverse mortar joint and the deviation coefficient Fzp of the longitudinal mortar joint:

[0043] in, i Indicates the number of all transverse mortar joints in the actual masonry part. i =1, 2, …, n , n is the total number of transverse mortar joints.

[0044] Step 204, obtain the deviation coefficient Fhp of the transverse mortar joint and the deviation coefficient Fzp of the longitudinal mortar joint, and calculate the masonry mortar joint deviation index Fp:

[0045] The calculation formula for the corresponding masonry joint deviation index Fp is as above.

[0046] When using, combine the contents in steps 201 to 204: Use the camera to capture the complete image of the actual masonry part, extract the mortar joints of the actual masonry part, and obtain the thickness of all horizontal mortar joints , Offset Angle and the thickness of all longitudinal mortar joints and offset angle , calculate the deviation coefficient Fhp of the transverse mortar joint and the deviation coefficient Fzp of the longitudinal mortar joint, and further calculate the masonry mortar joint deviation index Fp, which can intuitively understand the uniformity and consistency of the mortar joints during the masonry process, taking into account the overall deviation of the transverse and longitudinal mortar joints, and providing a scientific basis for the comprehensive evaluation of the masonry quality.

[0047] Step 3: Randomly select measurement points on the masonry part, knock on the measurement points with the same force, use a recording device to collect the knocking audio, and calculate the knocking audio evaluation index Yj and the masonry audio variance Cf.

[0048] The step three includes the following contents: Step 301: randomly select multiple measuring points on the masonry part, tap the measuring points with the same force, use a recording device to collect the tapping audio, use Fourier transform to convert the time domain signal into a frequency domain signal, divide the frequency range into a equal parts, and the width of each equal part is , get the amplitude in each frequency bin , and the number of frequency points within the frequency division , calculate the percussion audio evaluation index Yj:

[0049] Among them, k represents the sequence number corresponding to each frequency equal part, , a is the total number of frequency bins.

[0050] Step 302: Obtain the percussion audio evaluation index Yj of all measurement points and calculate the masonry audio variance Cf:

[0051] Where j represents the sequential number of all measurement points in the masonry part, , m is the total number of measurement points.

[0052] When using, combine the contents in steps 301 and 302: Randomly select measurement points on the masonry part, use the same force to knock at the measurement points, use recording equipment to collect knocking audio, calculate the knocking audio evaluation index Yj and masonry audio variance Cf, and analyze the knocking sound differences between different measurement points, so as to accurately locate the problem areas of masonry quality. For example, a large variance may mean that there are problems with the fullness or flatness of the mortar joints in certain areas. This can objectively reflect the quality of masonry and provide a scientific basis for acceptance work.

[0053] Step 4: Obtain the overall deviation coefficient Qzp, the mortar joint deviation index Fp and the audio variance Cf of the masonry part, calculate the comprehensive evaluation index Qp of the masonry, and issue an early warning of unqualified masonry quality.

[0054] The step 4 includes the following contents: Step 401, obtain the masonry overall deviation coefficient Qzp, masonry mortar joint deviation index Fp and masonry audio variance Cf of the masonry part, and calculate the masonry comprehensive evaluation index Qp:

[0055] in, Indicates the maximum value of the overall deviation coefficient of historical masonry, Indicates the minimum value of the overall deviation coefficient of historical masonry, Indicates the maximum value of the historical masonry joint deviation index, Indicates the minimum value of the historical masonry joint deviation index, represents the maximum value of the historical masonry audio variance, Indicates the minimum value of historical masonry audio variance.

[0056] Step 402: When the masonry comprehensive evaluation index Qp is greater than When , it indicates that the masonry quality is unqualified, and an early warning of unqualified masonry quality is issued. represents the mean value of the comprehensive evaluation index of historical masonry, Represents the variance of the comprehensive evaluation index of historical masonry.

[0057] When using, combine the contents in steps 401 and 402: The overall deviation coefficient Qzp, mortar joint deviation index Fp and audio variance Cf of the masonry part are obtained, the comprehensive evaluation index Qp of the masonry is calculated, and an early warning of unqualified masonry quality is issued. The quality of masonry can be quantitatively evaluated, avoiding the subjectivity and uncertainty of traditional visual inspection or empirical judgment. It can automatically issue an early warning of unqualified masonry quality, promptly remind relevant personnel to pay attention and take corresponding measures, and promptly rectify the unqualified parts, which will help the construction team optimize the construction plan, arrange resources reasonably, and improve construction efficiency.

[0058] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented using software, the above embodiments may be implemented in whole or in part in the form of a computer program product. A person of ordinary skill in the art may appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein may be implemented in electronic hardware, or in a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution.

[0059] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0060] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A design and construction method for building masonry based on BIM, characterized by: The steps include: Obtain the architectural design drawings, establish the BIM model of the building based on BIM technology, determine the brick size and mortar joint thickness that meet the standards, use a laser rangefinder to measure the actual size of the actual masonry part, and calculate the overall deviation coefficient Qzp of the masonry part; Use the camera to capture the complete image of the actual masonry part, extract the mortar joints of the actual masonry part, and obtain the thickness of all horizontal mortar joints , Offset Angle and the thickness of all longitudinal mortar joints and offset angle , calculate the deviation coefficient Fhp of the transverse mortar joint and the deviation coefficient Fzp of the longitudinal mortar joint, and further calculate the masonry mortar joint deviation index Fp; Randomly select measurement points on the masonry part, use the same force to knock at the measurement points, use recording equipment to collect knocking audio, and calculate the knocking audio evaluation index Yj and masonry audio variance Cf; The overall deviation coefficient Qzp, mortar joint deviation index Fp and audio variance Cf of the masonry part are obtained, the comprehensive evaluation index Qp of the masonry is calculated, and an early warning of unqualified masonry quality is issued.

2. A design and construction method for building masonry based on BIM according to claim 1, characterized in that: Use a laser rangefinder to measure the actual size of the actual masonry part, including the thickness Hd, height Gd, length Cd of the masonry part and the thickness Thd, height Tgd, length Tcd of the special part, and calculate the overall deviation coefficient Qzp of the masonry part: in, , and are the designed thickness, height and length of the masonry part, , and They are the designed thickness, height and length of special parts of the masonry.

3. The design and construction method of building masonry based on BIM according to claim 1, characterized in that: Get the thickness of all horizontal mortar joints , Offset Angle and the thickness of all longitudinal mortar joints and offset angle , calculate the deviation coefficient Fhp of the transverse mortar joint and the deviation coefficient Fzp of the longitudinal mortar joint: in, i Indicates the number of all transverse mortar joints in the actual masonry part. i =1, 2, …, n , n is the total number of transverse mortar joints.

4. The design and construction method of building masonry based on BIM according to claim 3, characterized in that: Obtain the deviation coefficient Fhp of the transverse mortar joint and the deviation coefficient Fzp of the longitudinal mortar joint, and calculate the masonry mortar joint deviation index Fp: The calculation formula for the corresponding masonry joint deviation index Fp is as above.

5. The design and construction method of building masonry based on BIM according to claim 1, characterized in that: Randomly select measurement points on the masonry part, knock at the measurement points with the same force, use a recording device to collect the knocking audio, use Fourier transform to convert the time domain signal into a frequency domain signal, divide the frequency range into a equal parts, and the width of each equal part is , get the amplitude in each frequency bin , and the number of frequency points within the frequency division , calculate the percussion audio evaluation index Yj: Among them, k represents the sequence number corresponding to each frequency equal part, , a is the total number of frequency bins.

6. The design and construction method of building masonry based on BIM according to claim 5, characterized in that: Get the percussion audio evaluation index Yj of all measurement points and calculate the masonry audio variance Cf: Where j represents the sequential number of all measurement points in the masonry part, , m is the total number of measurement points.

7. The design and construction method of building masonry based on BIM according to claim 6, characterized in that: Obtain the masonry overall deviation coefficient Qzp, masonry mortar joint deviation index Fp and masonry audio variance Cf of the masonry part, and calculate the masonry comprehensive evaluation index Qp: in, Indicates the maximum value of the overall deviation coefficient of historical masonry, Indicates the minimum value of the overall deviation coefficient of historical masonry, Indicates the maximum value of the historical masonry joint deviation index, Indicates the minimum value of the historical masonry joint deviation index, represents the maximum value of the historical masonry audio variance, Indicates the minimum value of historical masonry audio variance.

8. The design and construction method of building masonry based on BIM according to claim 7, characterized in that: When the masonry comprehensive evaluation index Qp is greater than When the masonry quality is not up to standard, an early warning is issued. represents the mean value of the comprehensive evaluation index of historical masonry, Represents the variance of the comprehensive evaluation index of historical masonry.

Images