A stability detection device and method for a large-span roof

Abstract

The application discloses a stability detection device and method for a large-span roof, and the detection method comprises the following steps: constructing a finite element analysis model according to design size parameters of the large-span roof, and screening target detection structural components according to actual loads; screening the areas of deformation sensors, vibration sensors and displacement sensors of the stability detection device on the target detection structural components; collecting actual deformation data, vibration data and displacement data of the target detection structural components on the large-span roof in use, calculating the stability coefficient of the target detection structural components in a data collection period, and further evaluating the stability of the large-span roof. T The detection device comprises a data collection module, a data sending module and a data processing center, wherein the data collection module comprises deformation sensors, vibration sensors and displacement sensors. The application can overcome the defects of traditional detection methods, realize high-precision, real-time and comprehensive monitoring of the stability of the large-span roof, and effectively guarantee the safety of building structures.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of building structure stability detection, in particular to a stability detection device and method for large-span roof. BACKGROUND

[0002] With the development of today's construction field, large-span roof structures are widely used in large-scale sports stadiums, exhibition halls, airport terminals and other landmark buildings. These large-span roofs usually have complex spatial structural forms and bear complex stresses and deformations caused by self-weight, wind load, snow load, personnel activity load and temperature changes. With the increase of service life, the deterioration of structural material performance, accidental impact and other factors may endanger the stability of the roof, and once the instability occurs, it will cause irreparable personnel casualties and property losses.

[0003] Traditional building structure detection methods, such as manual periodic inspection, local sampling detection, etc., are difficult to achieve comprehensive, real-time and accurate stability evaluation for large-span roofs with complex and large-area structures. Moreover, manual periodic inspection, local sampling detection and other methods often cannot reasonably evaluate the stability of some key and vulnerable structural components, and thus cannot accurately and comprehensively detect the stability of large-span roof structures. SUMMARY

[0004] In view of the above deficiencies of the prior art, the present application provides a stability detection device and method for large-span roof, which detects the stability of key structural components based on accurate mechanical analysis and then comprehensively evaluates the stability of large-span roof.

[0005] To achieve the above-mentioned application purposes, the technical solutions adopted by the present application are as follows:

[0006] A stability detection method for large-span roof is provided, which comprises the following steps:

[0007] S1: Construct a finite element analysis model according to the design size parameters of the large-span roof, apply actual loads in the installation and use process to each structural component of the finite element analysis model, select structural components that need to be detected for stability as target detection structural components according to the actual loads;

[0008] S2: Divide the target detection structural components into several sub-evaluation units, apply equivalent wind load to the target detection structural components, calculate the equivalent wind load response borne by each sub-evaluation unit, and select the area of the target detection structural components where the deformation sensor, vibration sensor and displacement sensor of the stability detection device are installed;

[0009] S3: After the stability testing device is installed on the target structural component of the large-span roof, it collects the actual deformation, vibration, and displacement data of the target structural component during use, and calculates the data acquisition cycle. T The stability coefficient of the internal target detection structural components is used to evaluate the stability of large-span roofs.

[0010] Further, step S1 includes:

[0011] S11: During the application of actual loads, calculate the importance coefficient of the structural components based on the type of stress they bear, the dispersion of different stress directions, and the magnitude of the stresses. ;

[0012] ;

[0013] in, The number of different types of stresses the stresses are subjected to. This represents the average number of different types of stresses experienced by all structural components. i Number the stresses that the structural components bear. b i For the structural component subjected to the first i The angular offset of a stress relative to the stress reference plane This represents the average angular offset of the stress experienced by all structural components relative to the stress reference plane. c i For the structural component subjected to the first i One stress value, This represents the average stress value experienced by all structural components. The weighting of the influence of the complexity of stress types on the importance of structural components. The weighting of the influence of the degree of stress dispersion borne by a structural component on the importance of the structural component. The stress values ​​borne by structural components are weighted according to their importance to the structural components, and satisfy the following conditions: , These are the position coordinates of the structural components;

[0014] S12: Set the threshold for the importance coefficient of evaluating whether structural components need to be tested for stability. ;

[0015] like If the structural component is subjected to complex stresses during its use in a large-span roof, it is determined that stability testing is required and it will be considered as a structural component to be tested.

[0016] like If the stress on the structural component is simple during use in a large-span roof, then stability testing is not required.

[0017] S13: After obtaining all the to-be-detected structural parts, extract the position coordinates of each to-be-detected structural part, and construct a to-be-detected structural part set and the to-be-detected structural part set a set of position coordinates of the to-be-detected structural parts , and calculate the dispersion coefficient of the distribution of the to-be-detected structural parts according to the position coordinates;

[0018] ;

[0019] wherein, s, v are two different to-be-detected structural part numbers, is the position coordinate of the to-be-detected structural part adjacent to the to-be-detected structural part s L s is the dispersion coefficient of the distribution of the to-be-detected structural part s , is the position coordinate of the to-be-detected structural part , is the position coordinate of the to-be-detected structural part s , is the number of to-be-detected structural parts, is the distance threshold for determining whether the positions of the to-be-detected structural parts are adjacent, v is the to-be-detected structural part number adjacent to the to-be-detected structural part V , is the number of to-be-detected structural parts adjacent to the to-be-detected structural part l , is the set of position coordinates of the to-be-detected structural parts adjacent to the to-be-detected structural part s ; u s S14: Set the dispersion coefficient threshold for determining whether the distribution of to-be-detected structural parts is dense U ; s If s , it is determined that the distribution of to-be-detected structural parts around the to-be-detected structural part is dense, and the to-be-detected structural part

[0020] is deleted from the to-be-detected structural part set ;

[0021] If , it is determined that the distribution of to-be-detected structural parts around the to-be-detected structural part s is reasonable, and the to-be-detected structural part s is retained;

[0022] If , it is determined that the distribution of to-be-detected structural parts around the to-be-detected structural part s is reasonable, and the to-be-detected structural part s is retained;

[0023] S15: Delete the to-be-detected structural part set​​​ The inner retained structure to be detected is taken as the target detection structure part to be detected for stability.

[0024] Further, the step S2 comprises:

[0025] S21: dividing the target detection structure part into several sub-evaluation units, applying an equivalent wind load to the target detection structure part, the equivalent wind load being a pulse load, and calculating the equivalent wind load response borne by each sub-evaluation unit ;

[0026] ;

[0027] wherein, e is the position of the sub-evaluation unit on the structure to be detected, is the peak factor of the equivalent wind load, is the equivalent wind load borne by the sub-evaluation unit e 1, e is the correlation coefficient between the equivalent wind load borne by the sub-evaluation unit 1 and the equivalent wind load borne by the sub-evaluation unit e , r is the standard deviation of the pulse load borne by the sub-evaluation unit I , r is the influence line of the equivalent wind load response r , t is the time of the pulse load, is the equivalent wind load response of the sub-evaluation unit e 1 at the time t , L is the length of the structure to be detected, is the equivalent wind load response of the sub-evaluation unit e 1 at the time t , is the standard deviation of the equivalent wind load response;

[0028] S22: obtaining the equivalent wind load response data of each sub-evaluation unit on the target detection structure part , w is the number of sub-evaluation units on the target detection structure part, is the equivalent wind load response of the sub-evaluation unit e w , screening out the maximum value in the equivalent wind load response data , and extracting the position e max of the corresponding sub-evaluation unit on the target detection structure part as the region of the deformation sensor, the vibration sensor and the displacement sensor of the installation stability detection device.

[0029] Further, step S3 comprises:

[0030] S31: After the stability detection device is installed on the target detection structural component of the large-span roof, the actual deformation data, vibration data and displacement data of the target detection structural component during use of the large-span roof are collected; the deformation data set, the vibration data set and the displacement data set of the target detection structural component collected in each data collection period T are respectively the deformation data, vibration data and displacement data collected in the T th collection period, q is the number of data collected in the collection period q T

[0031] S32: The stability coefficient of the target detection structural component in the data collection period T is calculated.

[0032]

[0033] wherein j is the number of data collected in the collection period T , and are respectively the deformation data and displacement data collected in the T th collection period, j is the average value of the deformation data in the deformation data set , is the average value of the vibration data in the vibration data set , is the maximum value of the vibration data in the vibration data set , is the allowable threshold value of the displacement data, is the sum of the displacement data calculated in the data collection period -1, T are respectively the influence weight coefficients of the deformation, vibration and displacement on the stability of the target detection structural component, and .

[0034] S33: According to the stability coefficients of all target detection structural components in the large-span roof during use , is the number of target detection structural components, ​​​​​​​​​​​Target detection structural component R In the acquisition cycle T The stability coefficient of the current data acquisition cycle T The stability coefficient of the large-span roof ;

[0035] S34: set the threshold value of evaluating the stability of the large-span roof , if , it is determined that the stability of the large-span roof in the current acquisition cycle T is poor, if , it is determined that the stability of the large-span roof in the current acquisition cycle T is good.

[0036] A stability detection device for a large-span roof is provided, which executes the above-mentioned stability detection method for the large-span roof, and comprises:

[0037] The data acquisition module comprises a deformation sensor, a vibration sensor and a displacement sensor, and is installed on the target detection structural component of the large-span roof to collect deformation, vibration and displacement data of the target detection structural component.

[0038] The data sending module is used to send the collected deformation, vibration and displacement data to the data processing center.

[0039] The data processing center analyzes the deformation, vibration and displacement data to evaluate the stability of the large-span roof.

[0040] The beneficial effects of the present application are as follows: the present application performs finite element mechanics analysis from the design parameters of the large-span roof, selects important structural components affecting the structural stability of the large-span roof according to the complexity of the stress of each structural component, and further serves as the basis for the stability detection of the large-span roof. At the same time, the installation position of the stability detection sensor is determined according to the stress analysis of the structural component, so as to ensure that the data collected by the sensor can accurately reflect the stability state of the structural component and improve the accuracy of the stability analysis of the large-span roof. The present application can overcome the shortcomings of traditional detection methods, realize high-precision, real-time and comprehensive monitoring of the stability of the large-span roof, and effectively ensure the safety of the building structure. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 The flowchart of the stability detection method for the large-span roof. DETAILED DESCRIPTION

[0042] The specific embodiments of the present application are described below to facilitate the understanding of the present application for those skilled in the art, but it should be clear that the present application is not limited to the scope of the specific embodiments, and for those skilled in the art, it is obvious that various changes are within the spirit and scope of the present application defined and determined by the appended claims, and all the inventions utilizing the concept of the present application are within the scope of protection.

[0043] As shown in the drawings, a stability detection method of a large-span roof cover comprises the following steps: Figure 1

[0044] S1: According to the design size parameters of the large-span roof cover, a finite element analysis model is constructed, the actual load in the installation and use process is applied to each structural component of the finite element analysis model, and the structural components that need to be detected for stability are selected as target detection structural components according to the actual load. Specifically, it includes:

[0045] S11: In the process of applying the actual load, the importance coefficient of the structural component is calculated according to the stress type borne by the structural component, the discreteness of different stress directions and the stress size .

[0046] .

[0047] Wherein, is the number of stress types borne, is the average value of the number of stress types borne by all structural components, i is the stress number borne by the structural component, b i is the angle offset of the first stress borne by the structural component relative to the stress reference plane, i is the average value of the angle offset of the stress borne by all structural components relative to the stress reference plane, i is the value of the first stress borne by the structural component, c is the average value of the stress value borne by all structural components, i is the importance influence weight of the complexity of the stress type on the structural component, is the importance influence weight of the stress dispersion degree borne by the structural component on the structural component, is the importance influence weight of the stress value borne by the structural component on the structural component, and satisfies , generally , , is the position coordinate of the structural component.

[0048] ​​This embodiment uses finite element analysis to obtain stress files for each structural component of a large-span roof structure. The importance of the structural component to the large-span roof structure is evaluated based on the complexity, dispersion, and magnitude of the stresses. The more types of stresses, the more dispersed they are, and the larger their values, the more important the structural component is to the large-span roof in terms of load-bearing and connection functions, and the more important it is for the stability of the large-span roof during use, thus requiring stability testing.

[0049] S12: Set the threshold for the importance coefficient of evaluating whether structural components need to be tested for stability. ;

[0050] like If the structural component is subjected to complex stresses during its use in a large-span roof, it is determined that stability testing is required and it will be considered as a structural component to be tested.

[0051] like If the stress on the structural component is simple during use in a large-span roof, then stability testing is not required.

[0052] S13: After obtaining all the structural components to be inspected, extract the position coordinates of each structural component to be inspected and construct a set of structural components to be inspected. and the set of structural components to be tested Set of position coordinates of the internal structural components to be inspected And calculate the dispersion coefficient of the distribution of the structural components to be detected based on the position coordinates;

[0053] ;

[0054] in, s, v These are the numbers of two different structural components to be inspected. To be compatible with the structural component under test s The position coordinates of the adjacent structural components to be inspected. L s For the structural component to be tested s The coefficient of dispersion of the distribution. For the structural component to be tested s Location coordinates, For the structural component to be tested v Location coordinates, V The number of structural components to be inspected. l To determine the structural component to be tested and the structural component to be tested s Distance threshold for determining whether a location is nearby. u To be compatible with the structural component under test s The numbers of the structural components to be inspected that are located nearby. U To be compatible with the structural component under test sThe number of adjacent structural components to be inspected. To be compatible with the structural component under test s A set of position coordinates of nearby structural components to be inspected.

[0055] The magnitude of the dispersion coefficient of the distribution of the structural components to be tested represents the density of the surrounding structural components to be tested. For structural components to be tested that are close to each other, the stability of only one structural component to be tested needs to be tested, which can reduce the cost of stability testing and the complexity of data processing.

[0056] S14: Set the threshold for the discrete coefficient to determine whether the distribution of the structural components to be detected is dense. ;

[0057] like Then determine the structural component to be tested. s The surrounding structural components to be tested are densely distributed, making the structural components to be tested... s From the set of structural components to be tested Internal deletion;

[0058] like Then determine the structural component to be tested. s The surrounding structural components to be inspected are reasonably distributed, and the structural components to be inspected are retained. s ;

[0059] S15: Assemble the structural components to be tested The structural components to be tested are retained internally as target structural components that require stability testing.

[0060] S2: Divide the target detection structural component into several sub-evaluation units, apply equivalent wind loads to the target detection structural component, calculate the equivalent wind load response of each sub-evaluation unit, and select areas on the target detection structural component where deformation sensors, vibration sensors, and displacement sensors for stability detection devices are installed. Specifically, this includes:

[0061] S21: Divide the target detection structural component into several sub-evaluation units, and apply an equivalent wind load to the target detection structural component. The equivalent wind load is an impulse load. Calculate the equivalent wind load response borne by each sub-evaluation unit. ;

[0062] ;

[0063] in, e This refers to the position of the sub-evaluation unit on the target detection structural component. The peak factor of the equivalent wind load. Sub-evaluation unit e Equivalent wind load and sub-evaluation unit e1 the correlation coefficient between the equivalent wind load received, is a sub-evaluation unit e 1 the standard deviation of the pulse load received, r is an equivalent wind load response, I r is an equivalent wind load response r , t is the time of the pulse load, is a sub-evaluation unit e at the time t of the equivalent wind load response, L is the length of the target detection structural component, is a sub-evaluation unit e 1 at the time t of the equivalent wind load response, is the standard deviation of the equivalent wind load response;

[0064] S22: Obtain the equivalent wind load response data of each sub-evaluation unit on the target detection structural component , w is the number of sub-evaluation units on the target detection structural component, is a sub-evaluation unit e w of the equivalent wind load response, and screen out the maximum value in the equivalent wind load response data , and extract the position of the sub-evaluation unit corresponding to the maximum value on the target detection structural component e max , as the area of the deformation sensor, vibration sensor and displacement sensor of the installation stability detection device.

[0065] S3: After the stability detection device is installed on the target detection structural component of the large-span roof, the actual deformation data, vibration data and displacement data of the target detection structural component during use on the large-span roof are collected, and the stability coefficient of the target detection structural component within the data collection period T is calculated, and the stability of the large-span roof is evaluated. Specifically, it includes:

[0066] S31: After the stability detection device is installed on the target detection structural component of the large-span roof, the actual deformation data, vibration data and displacement data of the target detection structural component during use on the large-span roof are collected; a deformation data set T , a vibration data set and a displacement data set of the target detection structural component collected within each data collection period are established, , and Data collection period T Inner q The deformation data, vibration data, and displacement data collected in this second batch. q Collection period T Number of times internal data was collected;

[0067] S32: Calculate the data acquisition cycle T Stability coefficient of internal target detection structural components ;

[0068] ;

[0069] in, j Collection period T Number of times internal data was collected. and Data collection period T Inner j The deformation and displacement data collected this time. For deformable datasets The average value of the internal deformation data, For vibration datasets The average value of internal vibration data, For vibration datasets The maximum value of internal vibration data, This is the allowable threshold for displacement data. Data collection cycle T -1 is the sum of the displacement data calculated. These are the weighting coefficients for the influence of deformation, vibration, and displacement on the stability of the target detection structural components, respectively. Generally take ;

[0070] S33: Based on the stability coefficient of all target detection structural components on the large-span roof during use. , To detect the number of structural components for the target. For the detection of target structural components R During the collection period T The stability coefficient is used to calculate the current data acquisition cycle. T Stability coefficient of large-span interior roof ;

[0071] S34: Set a threshold for evaluating the stability of large-span roofs. ,like Then determine the current collection period. T The stability of large-span roofs is relatively poor. Then determine the current collection period. TThe inner large-span roof cover has good stability.

[0072] The present application carries out finite element mechanics analysis from the design parameters of the large-span roof cover, screens important structural components influencing the stability of the large-span roof cover according to the complexity of stress of each structural component, and further serves as the basis for the stability detection of the large-span roof cover. Meanwhile, the installation position of the stability detection sensor is determined according to the stress analysis of the structural component, so as to ensure that the data collected by the sensor can accurately reflect the stability state of the structural component, and improve the accuracy of the stability analysis of the large-span roof cover. The present application can overcome the shortcomings of the traditional detection means, realize high-precision, real-time and comprehensive monitoring of the stability of the large-span roof cover, and effectively guarantee the safety of the building structure.

Claims

1. A method for detecting the stability of a large-span roof, characterized in that, Includes the following steps: S1: Construct a finite element analysis model based on the design dimensions of the large-span roof, apply actual loads during installation and use to each structural component on the finite element analysis model, and select structural components that need to be tested for stability based on the actual loads as target structural components for testing; S2: Divide the target detection structural component into several sub-evaluation units, apply an equivalent wind load to the target detection structural component, calculate the equivalent wind load response of each sub-evaluation unit, and select areas on the target detection structural component to install deformation sensors, vibration sensors and displacement sensors for stability detection devices. S3: After the stability testing device is installed on the target structural component of the large-span roof, it collects the actual deformation, vibration, and displacement data of the target structural component during use, and calculates the data acquisition cycle. T The stability coefficient of the internal target detection structural components is used to evaluate the stability of the large-span roof. Step S1 includes: S11: During the application of actual loads, calculate the importance coefficient of the structural components based on the type of stress they bear, the dispersion of different stress directions, and the magnitude of the stresses. ; ； in, The number of different types of stresses the stresses are subjected to. This represents the average number of different types of stresses experienced by all structural components. i Number the stresses that the structural components bear. b i For the structural component subjected to the first i The angular offset of a stress relative to the stress reference plane This represents the average angular offset of the stress experienced by all structural components relative to the stress reference plane. c i For the structural component subjected to the first i One stress value, This represents the average stress value experienced by all structural components. The weighting of the influence of the complexity of stress types on the importance of structural components. The weighting of the influence of the degree of stress dispersion borne by a structural component on the importance of the structural component. The stress values ​​borne by structural components are weighted according to their importance to the structural components, and satisfy the following conditions: , These are the position coordinates of the structural components; S12: Set the threshold for the importance coefficient of evaluating whether structural components need to be tested for stability. ; like If the structural component is subjected to complex stresses during its use in a large-span roof, it is determined that stability testing is required and it will be considered as a structural component to be tested. like If the stress on the structural component is simple during use in a large-span roof, then stability testing is not required. S13: After obtaining all the structural components to be inspected, extract the position coordinates of each structural component to be inspected and construct a set of structural components to be inspected. and the set of structural components to be tested Set of position coordinates of the internal structural components to be inspected And calculate the dispersion coefficient of the distribution of the structural components to be detected based on the position coordinates; ； in, s, v These are the numbers of two different structural components to be inspected. To be compatible with the structural component under test s The position coordinates of the adjacent structural components to be inspected. L s For the structural component to be tested s The coefficient of dispersion of the distribution. For the structural component to be tested s Location coordinates, For the structural component to be tested v Location coordinates, V The number of structural components to be inspected. l To determine the structural component to be tested and the structural component to be tested s Distance threshold for determining whether a location is nearby. u To be compatible with the structural component under test s The numbers of the structural components to be inspected that are located nearby. U To be compatible with the structural component under test s The number of adjacent structural components to be inspected. To be compatible with the structural component under test s The set of position coordinates of adjacent structural components to be inspected; S14: Set the threshold for the discrete coefficient to determine whether the distribution of the structural components to be detected is dense. ; like Then determine the structural component to be tested. s The surrounding structural components to be tested are densely distributed, making the structural components to be tested... s From the set of structural components to be tested Internal deletion; like Then determine the structural component to be tested. s The surrounding structural components to be inspected are reasonably distributed, and the structural components to be inspected are retained. s ; S15: Assemble the structural components to be tested The structural components to be tested are retained internally as target structural components that require stability testing.

2. The stability testing method for a large-span roof according to claim 1, characterized in that, Step S2 includes: S21: Divide the target detection structural component into several sub-evaluation units, and apply an equivalent wind load to the target detection structural component. The equivalent wind load is an impulse load. Calculate the equivalent wind load response borne by each sub-evaluation unit. ; ； in, e This refers to the position of the sub-evaluation unit on the target detection structural component. The peak factor of the equivalent wind load. Sub-evaluation unit e Equivalent wind load and sub-evaluation unit e 1. The correlation coefficient between the equivalent wind loads received. Sub-evaluation unit e The standard deviation of the pulse load received, r For the equivalent wind load response, I r Equivalent wind load response r Influence lines t For the timing of the pulse load, Sub-evaluation unit e At any moment t The equivalent wind load response, L To detect the length of the target structural component, Sub-evaluation unit e 1 at time t The equivalent wind load response, The standard deviation of the equivalent wind load response; S22: Obtain the equivalent wind load response data for each sub-evaluation unit on the target detection structural component. , w The number of sub-evaluation units on the target detection structural component. Sub-evaluation unit e w The equivalent wind load response was obtained, and the equivalent wind load response data were selected. The maximum value in and extract the maximum value. The corresponding sub-evaluation unit is located on the target detection structural component. e max This area serves as the location for installing deformation sensors, vibration sensors, and displacement sensors for stability testing devices.

3. The stability testing method for a large-span roof according to claim 2, characterized in that, Step S3 includes: S31: After the stability testing device is installed on the target structural component of the large-span roof, it collects the actual deformation, vibration, and displacement data of the target structural component during use; and establishes a data acquisition cycle. T Deformation dataset of target detection structural components acquired internally Vibration dataset and displacement dataset , , and Data collection period T Inner q The deformation data, vibration data, and displacement data collected in this second batch. q Collection period T Number of times internal data was collected; S32: Calculate the data acquisition cycle T Stability coefficient of internal target detection structural components ; ； in, j Collection period T Number of times internal data was collected. and Data collection period T Inner j The deformation and displacement data collected this time. For deformable datasets The average value of the internal deformation data, For vibration datasets The average value of internal vibration data, For vibration datasets The maximum value of internal vibration data, This is the allowable threshold for displacement data. Data collection cycle T -1 is the sum of the displacement data calculated. These are the weighting coefficients for the influence of deformation, vibration, and displacement on the stability of the target detection structural components, respectively. ; S33: Based on the stability coefficient of all target detection structural components on the large-span roof during use. , To detect the number of structural components for the target. For the detection of target structural components R During the collection period T The stability coefficient is used to calculate the current data acquisition cycle. T Stability coefficient of large-span interior roof ; S34: Set a threshold for evaluating the stability of large-span roofs. ,like If the stability of the large-span roof is poor within the current data collection period T, then it is determined that the stability of the large-span roof is poor. Then determine the current collection period. T The internal large-span roof has good stability.

4. A stability testing device for a large-span roof, comprising the stability testing method for a large-span roof as described in any one of claims 1-3, characterized in that, include: The data acquisition module, including deformation sensors, vibration sensors, and displacement sensors, is installed on the target detection structure component of the large-span roof to collect deformation, vibration, and displacement data of the target detection structure component. The data transmission module is used to send the collected deformation, vibration and displacement data to the data processing center; The data processing center analyzes deformation, vibration, and displacement data to assess the stability of large-span roofs.

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