Old granary transformation construction method

Abstract

The invention relates to the technical field of building transformation, in particular to an old granary transformation construction method, which comprises three main steps of data collection and analysis, reinforcement scheme design and reinforcement construction implementation, and specifically comprises the following steps of: carrying out preliminary field investigation and structure measurement on a granary, carrying out material performance detection and environment and load evaluation; the method comprises the following steps: collecting data of an old granary, inputting the collected data into an analysis model, outputting a reinforcement priority level and a reinforcement mode through the analysis model, formulating a reinforcement method and construction parameters of each reinforcement part according to the output reinforcement priority level and the reinforcement mode, and finally performing reinforcement construction on the granary. Reinforcement scheme design is optimized, construction efficiency is improved, the service life of the granary is prolonged, and maintenance cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of building renovation, and more specifically, it relates to a construction method for renovating old granaries. Background Art

[0002] As industrial heritage or historical buildings, old granaries have received increasing attention for protection and reuse due to their unique structures and cultural values. Renovating old granaries can not only preserve the historical features but also endow them with new functions, such as cultural and creative parks, commercial complexes, office spaces, etc. However, there are many challenges in the construction process of renovating old granaries.

[0003] Currently, the commonly used methods for strengthening the structures of old granaries mainly enhance the load-bearing capacity of the original structures by adding steel beams, steel columns, etc. However, the installation of steel structures is complex, with high requirements for construction accuracy, and it affects the aesthetics and spatial layout of the original buildings. There is also a method of injecting high-strength slurry into concrete structures to repair cracks and strengthen the structures. However, the grouting process has high requirements for the construction environment and has limited effects when dealing with complex structures.

[0004] Based on the above current situations, there is an urgent need for a new construction method to solve these problems. Summary of the Invention

[0005] Therefore, the purpose of the present invention is to provide a construction method for renovating old granaries, which can evaluate the structural health status of old granaries, optimize the design of reinforcement plans, improve construction efficiency, extend the service life of granaries, and reduce maintenance costs.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] A construction method for renovating old granaries, comprising the following steps:

[0008] Step S1, data collection and analysis:

[0009] Conduct a preliminary on-site inspection and structural measurement of the granary,

[0010] Conduct material performance testing and environmental and load assessment,

[0011] Input the collected data into the analysis model, and after analysis, the model outputs the reinforcement priority level and reinforcement method;

[0012] Step S2, reinforcement plan design:

[0013] According to the output reinforcement priority level and reinforcement method, formulate the reinforcement methods, construction parameters, and construction steps for each reinforced part;

[0014] Step S3, implement the reinforcement construction on the granary.

[0015] The present invention is further configured such that: in step S1, the structure measurement includes: measuring geometric parameters such as the height, diameter, and wall thickness of the grain bin using a laser rangefinder and a total station,

[0016] measuring and recording the geometric dimensions and shapes of each plane of the grain bin,

[0017] recording the three-dimensional coordinates of each key node of the grain bin and establishing a detailed geometric relationship model for subsequent structural analysis;

[0018] The material property detection includes: determining the actual compressive strength of the concrete through core drilling and compression tests,

[0019] using ultrasonic flaw detection and magnetic particle flaw detection techniques to detect the corrosion degree and integrity of the steel bars,

[0020] using a rebound hammer to measure the hardness of the concrete surface and evaluate the material properties,

[0021] recording and analyzing the material detection data to determine the degradation degree of the material properties;

[0022] The environment and load assessment includes:

[0023] measuring and recording the environmental parameters such as temperature, humidity, wind speed, and seismic activity frequency in the area where the grain bin is located,

[0024] using an anemometer and a seismograph to monitor and record the environmental load parameters,

[0025] calculating the current and predicted self-weight, live load, and wind load of the grain bin and evaluating their impact on the structure,

[0026] considering the increased load after the renovation and conducting a comprehensive load analysis.

[0027] The present invention is further configured such that: the analysis model includes:

[0028] Multivariate statistical analysis module: This module evaluates the structural health status by analyzing the geometric parameters, crack parameters, material property parameters, deformation parameters, and environmental load parameters of the grain bin,

[0029] Location classification module: According to the spatial layout and structural characteristics of the grain bin, the grain bin is divided into several key location areas, and different evaluation criteria and reinforcement requirements are set for each location area according to its function and stress conditions;

[0030] Priority calculation module: This module evaluates the risk levels of each reinforcement part using the fuzzy comprehensive evaluation method and the analytic hierarchy process according to the outputs of the multivariate statistical analysis module and the location classification module, and determines the reinforcement priority level by considering the weights and membership degrees of each risk factor to ensure that the high-risk parts are reinforced first;

[0031] Finite element analysis module: This module establishes the finite element models of each key position area, simulates the responses of the structure before and after reinforcement under different load conditions, analyzes the improvement effects of the reinforcement measures on the bearing capacity and stability of the structure by evaluating the displacement and stress distributions of the structure, and verifies the reinforcement plan.

[0032] Optimization algorithm module: This module uses the genetic algorithm to optimize the material selection and construction sequence in the reinforcement plan, and takes into account the structural safety, construction cost and time by setting a multi-objective optimization function.

[0033] Data visualization module: This module displays the analysis results and the reinforcement plan in visual graphs, provides an intuitive view of the structural health status and reinforcement effects, and assists in construction decision-making through three-dimensional visualization and an interactive interface.

[0034] The present invention is further configured as: The design of the reinforcement plan includes:

[0035] For the parts with the first-level reinforcement priority, select the steel structure reinforcement method, and determine the specific specifications, installation positions and connection methods of the steel beams and steel columns.

[0036] For the parts with the second-level reinforcement priority, select the carbon fiber reinforcement method, and determine the specifications of the carbon fiber cloth, the proportion of the adhesive and the construction steps.

[0037] For the parts with the third-level reinforcement priority, select the grouting reinforcement method, and determine the slurry ratio, injection volume and construction parameters.

[0038] For the top structure, select the prestressed reinforcement method, and determine the specifications of the prestressed steel strands, the tensioning force and the installation method.

[0039] The present invention is further configured as: The determination of the reinforcement requirements and priorities is based on the following criteria:

[0040] If the crack width exceeds 5 mm, and the crack extension length exceeds 2 m, the settlement exceeds 10 mm, the inclination angle exceeds 3 degrees, the actual concrete strength is 20% of the design strength, and the steel bar corrosion degree causes the bearing capacity to decrease by more than 30%,

[0041] When any of the above parameters reaches or exceeds its corresponding threshold, the part is rated as the first-level priority and needs to be immediately reinforced, and the steel structure reinforcement method is selected.

[0042] If the crack width is 3 mm - 5 mm, and the crack extension length is 1 m - 2 m, the settlement is 5 mm - 10 mm, the inclination angle is 1.5 - 3 degrees, the actual concrete strength is lower than the design strength by 10% - 20%, and the steel bar corrosion degree causes the bearing capacity to decrease to 15% - 30%,

[0043] When any of the above parameters reaches its corresponding threshold but does not exceed the first - level priority standard, the part is rated as the second - level priority and needs to be strengthened in a planned manner, and the carbon fiber reinforced strengthening method is adopted;

[0044] If the crack width is 1 mm - 3 mm, and the crack extension length is 0.5 - 1 m, the settlement is 2 mm - 5 mm, the inclination angle is 0.5 - 1.5 degrees, the actual concrete strength is 10% lower than the design strength, and the reduction in bearing capacity due to steel bar corrosion does not exceed 15%,

[0045] When any of the above parameters reaches its corresponding threshold but does not exceed the second - level priority standard, the part is rated as the third - level priority, and based on the construction location requirements, it is selectively strengthened by the grouting reinforcement method.

[0046] The present invention is further configured as follows: The steps of the steel structure strengthening method adopted for the first - level priority are as follows:

[0047] Clean the surface of the strengthening part, removing oil stains, dust and loose parts;

[0048] Prefabricate steel beams and steel column modules according to the design specifications to ensure that the dimensions and quality meet the requirements;

[0049] Use bolts to fix the prefabricated steel beams and steel column modules on the strengthening part and connect them by welding;

[0050] Spray an anti - corrosion coating on the surface of the installed steel structure, with a thickness of not less than 50 microns, to prevent corrosion;

[0051] Finally, check the installation quality of the steel structure and the integrity of the anti - corrosion coating.

[0052] The present invention is further configured as follows: The steps of the carbon fiber reinforcement method adopted for the second - level priority are as follows:

[0053] Use a brush and compressed air to clean the strengthening part to ensure good bonding of the adhesive and the carbon fiber cloth;

[0054] According to the crack position and size, pre - cut the carbon fiber cloth to cover the crack area and a 20 - cm - wide area around it;

[0055] Use a brush to evenly coat the epoxy resin adhesive on the strengthening part and the carbon fiber cloth to ensure full coverage of the adhesive;

[0056] Closely paste the cut carbon fiber cloth on the strengthening part, and use a squeegee to expel air bubbles to ensure no air bubbles and voids;

[0057] Maintain the construction environment temperature and humidity to promote full curing of the adhesive. The curing time is 48 hours, and finally, coat a protective layer on the surface of the carbon fiber cloth.

[0058] The present invention is further configured as follows: The steps of the grouting reinforcement method using the three - level priority are as follows:

[0059] Use a high - pressure water gun to clean the surface of the cracks in the reinforcement area, remove dust and loose parts to ensure good penetration of the slurry;

[0060] Drill holes at the cracks in the reinforcement area according to the design requirements, with a hole diameter of 10 mm and a hole spacing of 50 mm to ensure uniform distribution of the slurry;

[0061] Prepare a cement - based slurry according to the ratio of cement:sand:water = 1:2:0.5;

[0062] Use a grouting pump to slowly inject the slurry, control the grouting pressure not to exceed 10 MPa, and adopt the layered grouting method to ensure that the slurry completely fills the cracks;

[0063] After grouting, cover with a moisture - retaining film to maintain a moist environment, promote full curing of the slurry, and the curing time is 7 days;

[0064] After curing, repair the surface of the cracks to restore the original appearance and ensure the aesthetics of the structure.

[0065] The present invention is further configured as follows: The steps of the prestressed reinforcement method are as follows:

[0066] Drill holes at the key nodes of the top structure and install prestressed steel strands;

[0067] Use tensioning equipment to tension the prestressed steel strands, apply a prestressing force of 100 KN, ensure uniform tensioning force of the steel strands, and avoid local stress concentration;

[0068] Use bolts to fix the prestressed steel strands to prevent loosening; spray an anti - corrosion coating on the surface of the prestressed steel strands, with a thickness of not less than 50 microns to ensure long - term durability.

[0069] Finally, check the tensioning force and fixing effect of the prestressed steel strands to ensure that the reinforcement measures meet the design requirements.

[0070] The present invention is further configured as follows: Import the three - dimensional coordinate data of height, diameter, wall thickness, plane size, shape and key nodes collected by the laser rangefinder and total station into the BIM software, generate an accurate three - dimensional geometric model of the grain silo through the BIM software, and through the parametric design method, enable each part of the geometric relationship model to be adjusted and optimized according to the actual measurement data, and import the geometric relationship model into the finite - element analysis software to establish a finite - element model.

[0071] Comparing with the deficiencies of the prior art, the beneficial effects of the present invention are:

[0072] Through data collection and analysis, accurately evaluate the structural health status of each part of the granary, scientifically determine the reinforcement priority, ensure that high-risk parts are reinforced first, and effectively improve the safety and stability of the overall structure.

[0073] In particular, formulate corresponding reinforcement plans according to different priorities, and adopt various methods such as steel structure reinforcement, carbon fiber reinforcement, grouting reinforcement and prestressed reinforcement to ensure that the reinforcement measures match the specific structural damage and improve the practical application value of the reinforcement effect.

[0074] In particular, through optimization techniques such as multivariate statistical analysis, finite element analysis and genetic algorithm, reasonably select materials and construction sequence, taking into account structural safety, construction cost and time, significantly improve construction efficiency and reduce renovation cost.

[0075] Finally, on the basis of ensuring structural safety, through effective reinforcement measures, restore and improve the structure of the granary so that it can meet modern usage requirements, and achieve effective reuse of resources and sustainable development of the environment. Description of the Drawings

[0076] Figure 1 It is a schematic flow chart of the present invention. Detailed Implementation Modes

[0077] Refer to Figure 1 This embodiment details a construction method for the renovation of an old granary, including three main steps: data collection and analysis, reinforcement plan design, and reinforcement construction implementation.

[0078] Step S1, Data Collection and Analysis:

[0079] It includes preliminary on-site inspection and structural measurement of the old granary, material performance testing, and environmental and load assessment. Finally, the collected data is input into the analysis model to output the reinforcement priority level and reinforcement method. The following details each sub-step and the construction method of the geometric relationship model.

[0080] Preliminary On-site Inspection and Structural Measurement:

[0081] The equipment used is a laser rangefinder and a total station. The laser rangefinder is used to quickly and accurately measure geometric parameters such as the height, diameter and wall thickness of each part of the granary; the total station is used to measure the geometric dimensions and shapes of each plane of the granary with high precision, and record the three-dimensional coordinates of key nodes.

[0082] Measurement Steps:

[0083] Use the laser rangefinder to measure the height at multiple points from the ground to the top of the granary to obtain the overall height and the height distribution of each layer; set measurement points at different positions of the granary to ensure the comprehensiveness and accuracy of the height data.

[0084] For circular granaries, laser rangefinders measure the diameter from different directions to ensure the consistency of measurement results; record the changes in the granary diameter to identify possible geometric deformations or asymmetries.

[0085] Use laser rangefinders to measure the wall thickness at multiple positions on the granary wall and record the change trend of the wall thickness; pay special attention to the weak wall thickness areas to identify potential structural weak points.

[0086] Measurement methods for recording the geometric dimensions and shapes of each plane: Use a total station to scan each plane of the granary (such as the ground, walls, roof, etc.) to obtain detailed geometric dimension and shape data; for planes with irregular shapes or complex structures, adopt the multi-point measurement method to ensure the comprehensiveness and accuracy of geometric data.

[0087] Data recording:

[0088] The measurement data obtained by the total station are stored in electronic form and imported into building information modeling (BIM) software to generate detailed geometric drawings and 3D models of each plane; record the specific dimensions, shape characteristics and their mutual relationships of each plane to ensure the accuracy and reliability of the basic data for subsequent analysis.

[0089] Recording of the 3D coordinates of key nodes: Key nodes in the granary structure include but are not limited to beam-columns, load-bearing wall connection points, roof support points, etc. These nodes are key parts of the structure's force and stability; use a total station to set control points at each key node, accurately measure and record their 3D coordinates; adopt 3D scanning technology (such as laser scanning) to obtain detailed surface data around the nodes to ensure the accuracy and integrity of the node positions.

[0090] Import the recorded 3D coordinate data into BIM software to establish the precise position relationships of each key node; through the spatial analysis function of BIM software, verify the geometric relationships and force transfer paths between key nodes to ensure the structural integrity of the model.

[0091] Establishment of the geometric relationship model:

[0092] Import the height, diameter, wall thickness, plane dimensions, shapes and 3D coordinate data of key nodes collected by laser rangefinders and total stations into building information modeling (BIM) software (such as Revit, AutoCAD Civil 3D), and use BIM software to generate an accurate 3D geometric model of the granary, including detailed information of all key nodes and structural elements.

[0093] For complex structures, the point cloud data obtained by laser scanning is processed, and point cloud processing software (such as Leica Cyclone, Autodesk Recap) is used to convert the point cloud data into a format that can be used for BIM modeling; noise data is cleaned and filtered to ensure the accuracy and usability of the point cloud data; through parametric design methods, each part of the geometric relationship model can be flexibly adjusted and optimized according to the actual measurement data. Define the parameters of each structural component (such as the size and position of beams, columns, and walls) to achieve the adjustability and accuracy of the model.

[0094] Clarify the connection relationships of each structural component in the geometric model, such as the connection points of steel beams and steel columns, the interfaces of walls with beams and columns, etc., to ensure the structural integrity of the model and the accuracy of force transmission.

[0095] Use the connection tools of BIM software to automatically generate structural connection nodes and reduce human errors.

[0096] Verify the accuracy of the model by comparing the measurement data with the geometric model, and make adjustments and calibrations if necessary. Use structural health monitoring data (such as stress and strain monitoring) to further verify the geometric relationship model to ensure that the model can truly reflect the structural state of the granary.

[0097] Finite element analysis (FEA) preparation: Import the geometric relationship model into finite element analysis software (such as SAP2000, ETABS, ANSYS) to establish a detailed finite element model. According to the results of material performance tests, define the mechanical property parameters of materials such as concrete and steel bars, and assign the corresponding material properties to each structural unit of the model.

[0098] Simulate the stress conditions of the granary under the current load conditions, and evaluate the stress distribution and displacement of each structural part. Analyze the effects of different reinforcement measures (such as steel structure reinforcement, carbon fiber reinforcement, grouting reinforcement, prestressed reinforcement) on the structural bearing capacity and stability, and verify the effectiveness of the reinforcement scheme.

[0099] Material performance testing is an important part of evaluating the structural health status of old granaries, aiming to accurately understand the current situation of the main structural materials such as concrete and steel bars. It specifically includes the following aspects:

[0100] Determination of the actual compressive strength of concrete: Use a drill to extract concrete core samples from different positions and depths of the granary structure to ensure the representativeness and comprehensiveness of the samples. After curing the extracted concrete core samples, send them to the laboratory for compression tests. Use a standard compression testing machine (such as a Proctor compression testing machine) to apply gradually increasing pressure to the core samples until the specimens are damaged, and record the maximum bearing capacity at the time of failure. Calculate the actual compressive strength of the concrete according to the test results and compare it with the designed compressive strength to evaluate the performance degradation of the concrete.

[0101] Record the specific positions, depths, and test results of each core sample. Using statistical analysis methods, calculate parameters such as the average value and standard deviation of the concrete compressive strength, and analyze the spatial distribution and uniformity of the concrete strength. Determine the areas where the actual compressive strength of the concrete is lower than the design strength, which are the target areas to be prioritized for reinforcement.

[0102] Reinforcement corrosion degree and integrity detection: Use an ultrasonic flaw detector to perform non-destructive testing on the reinforcement, and evaluate the internal defects, cracks, and fractures of the reinforcement. By analyzing the reflection and propagation characteristics of the ultrasonic signals, judge the integrity and damage degree of the reinforcement.

[0103] Use magnetic particle flaw detection technology to magnetize the surface of the reinforcement, sprinkle magnetic powder, and make the magnetic powder gather at cracks and defects. Through visual inspection, identify and record the positions and severity of cracks, fractures, and other defects on the surface of the reinforcement. Record the test results of each reinforcement, including the defect type, position, and size. Evaluate the corrosion degree and integrity of the reinforcement based on the test data, and determine the reinforcement parts that affect the bearing capacity.

[0104] Mark the reinforcements with a corrosion severity exceeding 30% as the target areas that need to be prioritized for reinforcement or replacement.

[0105] Concrete surface hardness measurement: Use a rebound hammer to perform multi-point measurements on the concrete surface to evaluate the hardness and compactness of the concrete surface. By measuring the rebound distance, indirectly evaluate the compressive strength and surface quality of the concrete. Record the rebound values of each measurement point, and draw a distribution map of the concrete surface hardness. Analyze the relationship between the rebound value and the actual compressive strength, and verify the accuracy of the concrete hardness measurement results. Identify the areas where the rebound value is lower than the standard requirements, which are the target areas that need further reinforcement or repair.

[0106] Comprehensively organize the test data of the concrete compressive strength, reinforcement corrosion degree, and concrete surface hardness. Establish a material property database, record the specific parameters and evaluation results of each test point. By comparing the actual test data with the design parameters, evaluate the degradation degree of the material properties. Use statistical analysis and chart display to visually present the spatial distribution and trend of the material property degradation. Determine the parts where the material properties are significantly degraded, which are the important basis for determining the reinforcement priority.

[0107] The environmental and load assessment aims to comprehensively understand the environmental conditions of the granary and their impact on the structure, and ensure that the reinforcement plan can adapt to the actual use environment. It specifically includes the following aspects:

[0108] Environmental parameter measurement: Use temperature sensors and data loggers to continuously monitor the temperature changes in the area where the granary is located. Use hygrometers and data loggers to monitor the relative humidity inside and outside the granary and evaluate the impact of humidity on structural materials. Use anemometers to set measurement points at different heights and directions around the granary and record the changes in wind speed. Use seismographs to monitor and record the frequency and intensity of seismic activities in the area where the granary is located and evaluate the potential impact of seismic loads on the structure. Record the time-series data of each environmental parameter and analyze its change trend and extreme values.

[0109] Evaluate the accelerating aging and corrosion effects of extreme environmental conditions such as high temperature and high humidity on concrete and steel materials. Combine seismic activity data to analyze the impact of seismic loads on the granary structure and determine the safety of the structure under seismic conditions.

[0110] Load parameter monitoring: Calculate the self-weight load of the structure based on the geometric dimensions and material properties of the granary.

[0111] Live load assessment: Evaluate the possible increased live loads after the granary renovation, such as the weights of equipment, personnel, and goods. Wind load calculation: Combine the wind speed measurement data and structural geometric parameters and use the wind load calculation formula to calculate the structural response under wind loads. Record the specific values and acting point positions of each load type and draw the load distribution diagram.

[0112] Evaluate the bearing capacity of the existing structure under self-weight and live loads and identify potential overloaded areas.

[0113] Combine wind loads and seismic loads for comprehensive load analysis and evaluate the stability and safety of the structure under extreme load conditions.

[0114] Use structural analysis software (such as SAP2000, ETABS, ANSYS) for comprehensive load analysis and simulate the structural response of the granary under different load conditions. Combine the results of material performance tests and input actual material parameters to ensure the accuracy of the analysis results.

[0115] Combine self-weight, live loads, wind loads, and seismic loads and perform load combinations according to code requirements to simulate the structural forces under different working conditions.

[0116] Structural response calculation: Calculate the displacement, stress, and strain distributions of the structure under different load combinations and identify the weak links and potential failure modes of the structure.

[0117] Reinforcement requirement assessment: Based on the results of comprehensive load analysis, evaluate the reinforcement requirements for each part, determine the key areas that need to be strengthened, and specific reinforcement measures.

[0118] Result output: Output a comprehensive load analysis report, which details the stress response of the structure under different load conditions and the results of the safety assessment. Provide a scientific basis for the design of the reinforcement plan to ensure that the reinforcement measures can effectively address the load challenges in the actual use environment. Through multi-dimensional monitoring of environmental parameters and load parameters, comprehensively understand the environment where the granary is located and its impact on the structure, and ensure the adaptability and effectiveness of the reinforcement plan.

[0119] Accurate environmental and load data provide reliable inputs for structural analysis, improving the accuracy of finite element analysis and reinforcement plan design.

[0120] The analysis model described in the present invention includes the following modules: a multivariate statistical analysis module, a location classification module, a priority calculation module, a finite element analysis module, an optimization algorithm module, and a data visualization module. Each module works collaboratively to systematically evaluate the structural health status of the old granary, scientifically determine the reinforcement priorities, and formulate an optimized reinforcement plan. The functions and working processes of each module are described in detail below.

[0121] Multivariate statistical analysis module: Responsible for comprehensively analyzing the geometric parameters, crack parameters, material property parameters, deformation parameters, and environmental load parameters of the granary to evaluate the structural health status. Identify the key factors affecting structural stability through statistical methods and extract the main influencing factors to simplify the subsequent analysis process.

[0122] Receive all relevant parameter data collected in step S1, including geometric parameters, crack parameters, material property parameters, deformation parameters, and environmental load parameters; remove outliers and noise data, handle missing values; standardize data with different dimensions to ensure the accuracy of the analysis; use multiple linear regression or other appropriate regression methods to determine the degree of influence of each parameter on structural health; perform dimensionality reduction through PCA to extract the main influencing factors, reduce the complexity of the data, and improve the model calculation efficiency; output the weights of each parameter and the main influencing factors to provide a basis for the priority calculation module.

[0123] Location Classification Module: Divide the granary into several key location areas according to the spatial layout and structural characteristics of the granary. Different evaluation criteria and reinforcement requirements are set for each location area according to its function and stress conditions; Based on the geometric relationship model, the granary is divided into several key location areas such as the granary floor, columns, walls, and top structure; Analyze the functions and stress conditions of each area to determine its importance in the overall structure; According to the characteristics of each area, set corresponding evaluation criteria and reinforcement requirements to ensure that the reinforcement measures for different areas are targeted; Output the classification information and evaluation criteria of each key location area for use by the priority calculation module. Priority Calculation Module: Combine the outputs of the multivariate statistical analysis module and the location classification module, and use the fuzzy comprehensive evaluation method and the analytic hierarchy process (AHP) to evaluate the risk levels of each reinforcement part and determine the reinforcement priorities; Integrate the weights output by the multivariate statistical analysis module and the area information of the location classification module to form a comprehensive evaluation data set.

[0124] Fuzzy Comprehensive Evaluation Method: Define evaluation indicators and membership functions, and calculate the fuzzy comprehensive scores of each evaluation indicator.

[0125] Analytic Hierarchy Process (AHP): Construct a hierarchical structure model to determine the weights of each level; Determine the weights of each risk factor through the expert scoring method and calculate the comprehensive score; Priority Determination: Divide the reinforcement parts into first-level, second-level, and third-level priorities according to the comprehensive score; Output the priorities of each reinforcement part and corresponding reinforcement plan suggestions for use in the reinforcement plan design step.

[0126] Finite Element Analysis Module: Establish a finite element model to simulate the responses of the structure before and after reinforcement under different load conditions, evaluate the improvement effect of the reinforcement measures on the structural bearing capacity and stability, and verify the effectiveness of the reinforcement plan; Based on the geometric relationship model, use finite element analysis software (such as ANSYS, SAP2000) to establish finite element models of each key location area of the granary; According to the material performance test results, define the mechanical property parameters of materials such as concrete and steel bars, and assign corresponding material properties to each structural unit of the model; Apply the current and predicted self-weight, live load, wind load, etc. to simulate the actual use conditions; Calculate the displacement and stress distributions of the structure under different load conditions and evaluate the changes in the structural responses before and after reinforcement.

[0127] Reinforcement Effect Evaluation: Compare the structural responses before and after reinforcement, and analyze the improvement effect of the reinforcement measures on the structural bearing capacity and stability; Provide quantitative analysis results of the improvement of the structural performance by the reinforcement measures for use by the optimization algorithm module.

[0128] Optimization algorithm module: Adopt genetic algorithm (GA) or particle swarm optimization (PSO) algorithm to optimize the material selection and construction sequence in the reinforcement plan, taking into account structural safety, construction cost and time, ensuring that the reinforcement plan maximizes cost-effectiveness while meeting design specifications; Set multi-objective optimization functions, including structural safety, construction cost and time.

[0129] Encode the material selection and construction sequence of the reinforcement plan to form a format suitable for genetic algorithm processing; Perform operations such as selection, crossover, and mutation to generate new reinforcement plans; Calculate the fitness of each reinforcement plan according to the optimization objectives and screen out the optimal plan; Repeat genetic operations and fitness evaluation until the optimization objectives reach the preset conditions; Output the optimal reinforcement plan, including material selection and construction sequence suggestions, for use by the data visualization module.

[0130] Data visualization module: Display the analysis results and reinforcement plans in visual graphs to provide an intuitive view of the structural health status and reinforcement effects. Through 3D visualization and an interactive interface, assist in construction decision-making and improve the transparency and accuracy of the construction process; Integrate the result data of multivariate statistical analysis, priority calculation, and finite element analysis to form a comprehensive visual dataset.

[0131] Use BIM software (such as Revit) to generate a 3D geometric relationship model of the granary, showing the specific locations of each reinforcement part and the reinforcement plan; Generate heat maps, stress distribution maps, and reinforcement effect diagrams of the structural health status to intuitively display the structural stress conditions and reinforcement effects; Provide an interactive interface for users, allowing construction personnel to adjust parameters and view the reinforcement plan effects in real time for plan optimization; Assist construction personnel in making scientific reinforcement decisions through visual results to ensure the accurate implementation of reinforcement measures; Generate a detailed visual report for construction planning and management to improve the transparency and controllability of the construction process.

[0132] In the construction method for the renovation of old granaries, the determination of reinforcement priorities is based on multiple key parameters, including crack width, crack extension length, settlement amount, inclination angle, actual concrete strength, and steel bar corrosion degree. In order to scientifically and reasonably divide the reinforcement priorities, the present invention sets parameter thresholds for three levels of priorities (level one, level two, and level three). The origin and mutual relationship of each level of parameters are described in detail below.

[0133] Through on-site inspections and reinforcement case analyses of multiple old granaries, data on the impact of various parameters on the structural safety in actual projects were collected. These data helped determine the critical values of different parameters in practical applications, ensuring the practicality and reliability of the thresholds. Finite element analysis software (such as ANSYS, SAP2000) was used to simulate the stress and deformation conditions of the structure under different parameter conditions, and to evaluate the specific impact of each parameter on the structural stability. Through numerical simulation, the parameter thresholds were verified and optimized to ensure their theoretical rationality.

[0134] First-level priority:

[0135] Crack width: exceeding 5 mm

[0136] Crack extension length: exceeding 2 m

[0137] Settlement amount: exceeding 10 mm

[0138] Inclination angle: exceeding 3 degrees

[0139] Actual concrete strength: only 20% of the designed strength

[0140] Degree of steel corrosion: resulting in a reduction in load-bearing capacity by more than 30%

[0141] The parameter thresholds for the first-level priority are set at a relatively high risk level, meaning that once these parameters exceed the thresholds, they will significantly affect the overall load-bearing capacity and stability of the structure. For example, a crack width exceeding 5 mm and an extension length exceeding 2 m indicate that the structure has serious damage, which may lead to local or overall instability of the structure. Similarly, the actual concrete strength being only 20% of the designed strength, and the degree of steel corrosion resulting in a reduction in load-bearing capacity by more than 30% both indicate that the main load-bearing materials of the structure have seriously deteriorated and immediate reinforcement measures are required.

[0142] Second-level priority:

[0143] Crack width: 3 mm to 5 mm

[0144] Crack extension length: 1 m to 2 m

[0145] Settlement amount: 5 mm to 10 mm

[0146] Inclination angle: 1.5 degrees to 3 degrees

[0147] Actual concrete strength: 10% to 20% lower than the designed strength

[0148] Degree of steel corrosion: resulting in a reduction in load-bearing capacity to 15% to 30%

[0149] The parameter thresholds of the second priority are set at a medium risk level, indicating a certain degree of damage to the structure, which affects the structural performance but has not reached a severe level. The thresholds of these parameters are based on empirical data and finite element analysis, indicating that within these ranges, the load-bearing capacity and stability of the structure can still be effectively improved through planned strengthening measures. For example, when the crack width is between 3 mm and 5 mm, it indicates a moderate degree of stress concentration, and strengthening measures such as carbon fiber reinforcement need to be taken to prevent further deterioration.

[0150] Third priority:

[0151] Crack width: 1 mm to 3 mm

[0152] Crack extension length: 0.5 m to 1 m

[0153] Settlement amount: 2 mm to 5 mm

[0154] Inclination angle: 0.5 degrees to 1.5 degrees

[0155] Actual concrete strength: Slightly reduced, less than 10%

[0156] Degree of steel corrosion: Resulting in a load-bearing capacity reduction of no more than 15%

[0157] The parameter thresholds of the third priority are set at a low risk level, indicating slight damage to the structure, which has little impact on the overall load-bearing capacity. The thresholds of these parameters are based on the initial stage of material property degradation and the slight influence of environmental loads. For parts where these parameters reach the thresholds but do not exceed the second priority standards, relatively simple strengthening methods such as grouting reinforcement can be selected, and regular monitoring can be carried out to prevent further expansion of the damage.

[0158] The crack width and extension length together reflect the non-uniformity of structural stress and the degree of stress concentration. Wider cracks are usually accompanied by longer extension lengths, indicating that the structure is more stressed and damaged in this area. Therefore, when evaluating the reinforcement priority, the relative relationship between the two needs to be considered comprehensively to avoid evaluation deviations caused by a single parameter.

[0159] The settlement amount and inclination angle are two important parameters reflecting the degree of structural deformation. A larger settlement amount often leads to the inclination of the structure, accelerating the instability of the structure. The comprehensive evaluation of the two can more comprehensively reflect the impact of structural deformation on the overall stability, ensuring that the strengthening measures can effectively cope with the potential risk of structural instability.

[0160] The compressive strength of concrete and the degree of steel corrosion directly affect the bearing capacity of the structure. The reduction of compressive strength and steel corrosion will weaken the bonding strength between concrete and steel, and reduce the stability and bearing capacity of the overall structure. Comprehensive evaluation of these two parameters can more accurately reflect the degradation of structural materials and provide a more powerful basis for the formulation of reinforcement plans.

[0161] Environmental factors (such as temperature, humidity, wind speed, seismic activity) will affect the degradation speed and degree of material properties. High temperature and high humidity environments accelerate the aging and corrosion of concrete and steel, increasing the complexity of structural forces. Therefore, when setting parameter thresholds, the influence of environmental loads on material properties needs to be considered to ensure that the reinforcement plan can meet the usage requirements under different environmental conditions.

[0162] In actual engineering, the setting of each parameter threshold not only independently affects the division of reinforcement priorities, but also has mutual correlations and comprehensive influences. Therefore, this invention adopts a comprehensive influence analysis method to ensure that the setting of parameter thresholds can comprehensively reflect the health status and reinforcement requirements of the structure.

[0163] Through multivariate statistical analysis and the analytic hierarchy process, the weights of each parameter are reasonably allocated to ensure that in the division of reinforcement priorities, the influence of each parameter is scientifically reflected. The weight allocation is based on the actual influence degree of the parameter on the structural health, avoiding a certain parameter from overly dominating the evaluation results.

[0164] Consider the interaction between parameters, such as crack width and extension length, settlement and inclination angle, etc. By introducing interaction factors, the accuracy of the reinforcement priority division is improved. The interaction factors are determined through finite element analysis and fuzzy comprehensive evaluation method to ensure that the evaluation results can comprehensively reflect the comprehensive stress state of the structure.

[0165] Construct a comprehensive evaluation model, incorporate each parameter and its mutual relationship into the model, and determine the priorities of each reinforcement part through weighted scoring and fuzzy evaluation. The comprehensive evaluation model is optimized through iteration and dynamically adjusted to ensure that the division of reinforcement priorities is scientific and reasonable.

[0166] In step S3, according to the reinforcement priority and reinforcement method, the reinforcement methods, construction parameters and construction steps of each reinforcement part are formulated. The following details the reinforcement methods corresponding to different priorities and their specific implementation steps:

[0167] Reinforcement design of parts with the first-level priority:

[0168] Clean the surface of the reinforcement part to remove oil stains, dust and loose parts;

[0169] Prefabricate steel beam and steel column modules according to the design specifications to ensure that the dimensions and quality meet the requirements;

[0170] Use high-strength bolts to fix the prefabricated steel beams and steel column modules on the reinforcement parts; adopt welding technology to weld the connection parts to ensure the overall stability of the structure;

[0171] Spray an anti-corrosion coating on the surface of the installed steel structure, with a thickness of not less than 50 microns; avoid coating missing or weak areas; check the installation quality of the steel structure to ensure that the bolt connection and welding quality meet the design requirements; check the integrity and coverage of the anti-corrosion coating to ensure the anti-corrosion effect.

[0172] Reinforcement design for secondary priority parts:

[0173] The carbon fiber cloth has a width of 1000 mm and a thickness selected according to the structural requirements; the adhesive ratio is 2:1 for epoxy resin and curing agent. The coverage range is the crack area and 200 mm wide around it.

[0174] Use a brush and compressed air to clean the reinforcement part to ensure good bonding of the adhesive and the carbon fiber cloth; grind the crack area to increase the surface roughness and improve the bonding effect;

[0175] According to the crack position and size, pre-cut the carbon fiber cloth to cover the crack area and 200 mm wide around it, ensure that the size and shape of the carbon fiber cloth match the crack area, and avoid excessive or insufficient coverage; use a brush to evenly coat the epoxy resin adhesive on the reinforcement part and the carbon fiber cloth, ensure that the adhesive is fully covered, control the coating thickness of the adhesive, and avoid too thick or too thin affecting the bonding effect; closely paste the cut carbon fiber cloth on the reinforcement part, use a scraper to expel air bubbles to ensure no air bubbles and voids, and enhance the bonding strength; maintain the construction environment temperature and humidity to promote the full curing of the adhesive. The curing time is 48 hours. Use shielding materials to cover the reinforcement area to prevent external environmental interference; coat a protective layer on the surface of the carbon fiber cloth to prevent environmental erosion and extend the service life.

[0176] Reinforcement design for tertiary priority parts:

[0177] The slurry ratio is cement:sand:water = 1:2:0.5; the injection volume is calculated according to the crack length L and depth D, and the volume V = L×D×0.1 cubic meters; the grouting pressure does not exceed 10 MPa; the drilling parameters are a hole diameter of 10 mm and a hole spacing of 50 mm; the curing time is to keep the environment moist for 7 days.

[0178] Use a high-pressure water gun to clean the surface of the cracks in the reinforced area, removing dust and loose parts to ensure that the crack surface is clean and wet, promoting good penetration of the grout; drill holes at the cracks in the reinforced area according to the design requirements, with a hole diameter of 10 mm and a hole spacing of 50 mm, ensuring that the depth and distribution of the drilled holes meet the design requirements to avoid over-drilling or under-drilling; prepare the cement-based grout according to the ratio of cement:sand:water = 1:2:0.5; slowly inject the grout using a grouting pump, controlling the grouting pressure not to exceed 10 MPa. Adopt the layered grouting method to ensure that the grout completely fills the cracks, avoiding voids and unfilled areas; after grouting, cover with a moisture-retaining film to maintain a wet environment, promoting full curing of the grout. The curing time is 7 days to ensure that the grout reaches the design strength; after curing, repair the crack surface to restore the original appearance, using appropriate repair materials for surface filling and beautification to ensure the aesthetics of the structure.

[0179] Reinforcement design of the top structure:

[0180] The specification of the prestressed steel strand is steel strand Φ20 mm; the tensioning force: 100 kN; the installation position is the key node of the top structure.

[0181] Drill holes at the key nodes of the top structure, install the prestressed steel strands according to the design drawings, ensuring that the position and quantity of the steel strands meet the design requirements and the stress is evenly distributed; use tensioning equipment to tension the prestressed steel strands, applying a prestressing force of 100 kN; monitor the tensioning force during the tensioning process to ensure that the tensioning force is uniform and avoid local stress concentration; use high-strength bolts to fix the prestressed steel strands in the predetermined position to prevent the steel strands from loosening or shifting during use. Spray an anti-corrosion coating on the surface of the prestressed steel strands with a thickness of not less than 50 microns to prevent the influence of corrosion on the performance of the steel strands; check the tensioning force and fixing effect of the prestressed steel strands to ensure that the reinforcement measures meet the design requirements; conduct a structural bearing capacity test to verify whether the reinforcement effect meets the expectations; during the tensioning process, use a tensiometer to monitor the tensioning force of the prestressed steel strands in real time to ensure that the tensioning force is evenly distributed; record the data during the tensioning process as a reference for subsequent structural health monitoring.

[0182] Overview of the implementation case:

[0183] Name of the granary: Granary A

[0184] Type of granary: Circular reinforced concrete structure

[0185] Year of construction: 1985

[0186] Geographical location: A certain city in a certain province

[0187] Height of the granary: 20 m, diameter of the granary: 30 m, total volume: 14,137 cubic meters, wall thickness 0.4 m, size of the entrance: diameter 2 m.

[0188] Conduct a preliminary on-site inspection, structural measurement, material property testing, and structural health assessment of the environment and loads for the old granary. The specific data is shown in Table 1 below:

[0189] Table 1

[0190] Based on the data in Table 1, the comparison Table 2 is obtained by using this method and traditional reinforcement techniques: Table 2

[0191] Through the comparative analysis of the data in Table 2: By optimizing the construction steps and material selection, the construction period is shortened, the reinforcement cost is reduced, and the improvement of construction efficiency and the maximization of economic benefits are achieved; The systematic reinforcement measures significantly extend the service life of the granary and reduce the frequency and cost of later maintenance and repair; According to the priority of different reinforcement parts, a variety of reinforcement methods are adopted to ensure that the reinforcement measures match the specific structural damage, and the practical application value of the reinforcement effect is improved.

[0192] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any ordinary changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention should be included in the protection scope of the present invention.

Claims

1. A construction method for renovating an old granary, characterized in that: The following steps are involved: Step S1: Data collection and analysis: Conduct preliminary site survey and structural survey of the granary, Conduct material performance testing and environmental and load assessments, Input the collected data into the analysis model, and output the reinforcement priority and reinforcement method through the analysis model; Step S2: Reinforcement scheme design: According to the output reinforcement priority and reinforcement method, formulate the reinforcement method, construction parameters and construction steps for each reinforcement part; Step S3: Implement reinforcement construction on the granary.

2. The old granary reconstruction construction method according to claim 1 is characterized in that: The structural measurement in step S1 includes: using a laser rangefinder and a total station to measure the height, diameter, wall thickness and other geometric parameters of the granary. Measure and record the geometric dimensions and shapes of each plane of the granary, Record the three-dimensional coordinates of each key node of the granary and establish a detailed geometric relationship model for subsequent structural analysis; Material performance testing includes: determining the actual compressive strength of concrete through core sampling and compression testing, Ultrasonic and magnetic particle testing techniques are used to detect the corrosion degree and integrity of steel bars. Use a rebound hammer to measure the hardness of concrete surfaces and evaluate material properties. Record and analyze material test data to determine the degree of degradation of material properties; Environmental and load assessments include: Measure and record environmental parameters such as temperature, humidity, wind speed, and frequency of seismic activity in the area where the granary is located. Use anemometers and seismometers to monitor and record environmental load parameters, Calculate the current and predicted deadweight, live load and wind load of the silo and assess their impact on the structure. Considering the increased load after reconstruction, a comprehensive load analysis is conducted.

3. The old granary reconstruction construction method according to claim 2 is characterized in that: The analytical model includes: Multivariate statistical analysis module: This module evaluates the structural health status by analyzing the geometric parameters, crack parameters, material performance parameters, deformation parameters and environmental load parameters of the granary. Location classification module: According to the spatial layout and structural characteristics of the granary, the granary is divided into several key location areas, and each location area is set with different evaluation standards and reinforcement requirements according to its function and stress conditions; Priority calculation module: This module uses the fuzzy comprehensive evaluation method and hierarchical analysis method to evaluate the risk level of each reinforcement location based on the output of the multivariate statistical analysis module and the location classification module. By considering the weight and membership of each risk factor, the reinforcement priority level is determined to ensure that high-risk locations are reinforced first; Finite element analysis module: This module builds a finite element model of each key location area to simulate the response of the structure under different load conditions before and after reinforcement. By evaluating the displacement and stress distribution of the structure, it analyzes the effect of reinforcement measures on the structural bearing capacity and stability, and verifies the reinforcement plan; Optimization algorithm module: This module uses genetic algorithms to optimize the material selection and construction sequence in the reinforcement scheme, and takes into account structural safety, construction cost and time by setting a multi-objective optimization function; Data visualization module: This module displays the analysis results and reinforcement schemes in the form of visual graphics, provides an intuitive view of the structural health status and reinforcement effect, and assists construction decision-making through three-dimensional visualization and interactive interface.

4. The old granary reconstruction construction method according to claim 2 is characterized in that: The reinforcement scheme design includes: Select the steel structure reinforcement method for the parts with the first-level reinforcement priority, and determine the specific specifications, installation locations and connection methods of steel beams and columns; Select the carbon fiber reinforcement method for the parts with the second priority of reinforcement, and determine the specifications of the carbon fiber cloth, the proportion of adhesive and the construction steps; For the parts with the third priority level, select the grouting reinforcement method and determine the grout ratio, injection volume and construction parameters; For the top structure, select the prestressed reinforcement method and determine the specifications, tensioning strength and installation method of the prestressed steel strands.

5. The old granary reconstruction construction method according to claim 4 is characterized in that: The reinforcement requirements and priorities are determined based on the following criteria: If the crack width exceeds 5 mm, the crack extension length exceeds 2 meters, the settlement exceeds 10 mm, the inclination angle exceeds 3 degrees, the actual strength of the concrete is 20% of the design strength, and the degree of steel corrosion causes the bearing capacity to drop by more than 30%, When any of the above parameters reaches or exceeds its corresponding threshold, the location is assessed as a first-level priority and requires immediate reinforcement, and the steel structure reinforcement method is selected; If the crack width is 3mm-5mm, the crack extension length is 1m-2m, the settlement is 5mm-10mm, the inclination angle is 1.5-3 degrees, the actual strength of the concrete is 10%-20% lower than the design strength, and the degree of steel corrosion causes the bearing capacity to drop to 15%-30%, When any of the above parameters reaches its corresponding threshold but does not exceed the first-level priority standard, the part is assessed as a second-level priority and requires planned reinforcement, and the carbon fiber reinforcement method is used; If the crack width is 1 mm-3 mm, the crack extension length is 0.5-1 m, the settlement is 2 mm-5 mm, the inclination angle is 0.5-1.5 degrees, the actual strength of the concrete is 10% lower than the design strength, and the degree of steel corrosion causes the bearing capacity to decrease by no more than 15%, When any of the above parameters reaches its corresponding threshold but does not exceed the secondary priority standard, the site is assessed as a tertiary priority and is selectively reinforced by grouting reinforcement method based on the construction location requirements.

6. The old granary reconstruction construction method according to claim 5 is characterized in that: The steps of the steel structure reinforcement method adopted in the first-level priority are as follows: Clean the surface of the reinforced part to remove oil, dust and loose parts; Prefabricate steel beam and column modules according to design specifications, ensuring that the dimensions and quality meet the requirements; The prefabricated steel beam and column modules are fixed to the reinforcement parts using bolts and connected by welding; Spray anti-corrosion coating on the surface of the installed steel structure with a thickness of not less than 50 microns to prevent corrosion; Finally, check the installation quality of the steel structure and the integrity of the anti-corrosion coating.

7. The old granary reconstruction construction method according to claim 6 is characterized in that: The steps of the carbon fiber reinforcement method adopted by the secondary priority are as follows: Use a brush and compressed air to clean the reinforcement area to ensure good bonding between the adhesive and the carbon fiber cloth; According to the location and size of the crack, pre-cut carbon fiber cloth to cover the crack area and its surrounding area with a width of 20cm; Use a brush to evenly apply epoxy resin adhesive to the reinforcement parts and carbon fiber cloth, ensuring that the adhesive is fully covered; Stick the cut carbon fiber cloth tightly on the reinforced part, use a scraper to remove bubbles, and ensure there are no bubbles or gaps; Maintain the temperature and humidity of the construction environment to promote full curing of the adhesive. The curing time is 48 hours, and finally apply a protective layer on the surface of the carbon fiber cloth.

8. The old granary reconstruction construction method according to claim 7 is characterized in that: The steps of the grouting reinforcement method adopted by the third level priority are as follows: Use a high-pressure water gun to clean the crack surface of the reinforced part to remove dust and loose parts to ensure good penetration of the slurry; Drill holes at the cracks of the reinforced parts according to the design requirements, with a hole diameter of 10 mm and a hole spacing of 50 mm to ensure that the slurry can be evenly distributed; Prepare cement-based slurry according to the ratio of cement: sand: water = 1:2:0.5; Use a grouting pump to slowly inject the slurry, control the grouting pressure not to exceed 10 MPa, and use the layered grouting method to ensure that the slurry completely fills the cracks; After the grouting is completed, cover with a moisturizing film to maintain a moist environment and promote full solidification of the slurry. The solidification time is 7 days. After curing, the crack surface is repaired to restore the original appearance and ensure the beauty of the structure.

9. The old granary reconstruction construction method according to claim 8 is characterized in that: The steps of the prestressed reinforcement method are as follows: Drill holes at key nodes of the top structure and install prestressed steel strands; Use tensioning equipment to tension the prestressed steel strands, apply a prestressing force of 100KN, ensure uniform tensioning of the steel strands, and avoid local stress concentration; Use bolts to fix the prestressed steel strands to prevent loosening; spray anti-corrosion coating on the surface of the prestressed steel strands with a thickness of not less than 50 microns to ensure long-term durability; Finally, check the tensioning strength and fixing effect of the prestressed steel strands to ensure that the reinforcement measures meet the design requirements.

10. The old granary reconstruction construction method according to claim 3 is characterized in that: The three-dimensional coordinate data of height, diameter, wall thickness, plane size, shape and key nodes collected by the laser rangefinder and total station are imported into the BIM software, and an accurate three-dimensional geometric model of the granary is generated through the BIM software. Through the parametric design method, the various parts of the geometric relationship model can be adjusted and optimized according to the actual measurement data, and the geometric relationship model is imported into the finite element analysis software to establish a finite element model.

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