Analysis method for tunnel side-penetrating frame structure building based on foundation stress loss

Abstract

The invention provides a foundation stress loss-based tunnel side-crossing frame structure building analysis method, which is an analysis means for solving the problem of potential damage to adjacent buildings when a shield tunnel laterally crosses existing buildings on the earth surface. By simplifying building damage analysis steps, optimizing a building damage identification method, determining a building damage standard and quantifying a building damage condition, the purposes of realizing safe construction of tunnel construction and ensuring the safety and usability of a surface building after disturbance are achieved. Comprising the following implementation steps: step 1), simplifying a building structure; step 2), building foundation settlement calculation; 3) calculating ground surface settlement; 4) solving the internal force of the building; (5) building resistance-stress comparison is carried out; a structural safety coefficient eta is adopted for rating, the rating is divided into four grades, and different grades correspond to different works.

Description

Technical Field

[0001] The invention relates to a method for analyzing surface building damage by applying building damage identification standards when tunnel construction disturbs the stratum and causes foundation stress loss, and belongs to the field of geotechnical construction and tunnel engineering. Background Art

[0002] Urban rail transit is particularly important as the most important and basic task in the process of modern urbanization. The development and utilization of urban underground transportation resources are gradually becoming the center and focus of urban transportation construction.

[0003] As an important part of urban infrastructure, tunnel construction is growing in scale and number. During tunnel construction, excavation destroys the structural balance of the original soil in the stratum, causing deformation of the surrounding soil. This deformation may be transmitted to the foundation, causing uneven settlement of the foundation, and eventually leading to cracks, tilts, or even damage to the upper buildings.

[0004] As the requirements for building functions and building shapes become increasingly diversified, building structure design has attracted people's attention. As a relatively common model, building frame structure design has been widely used in various types of buildings. At present, in the design of the frame structure of multi-story buildings in my country, the integration and integration with foreign advanced concepts have been gradually realized, and the system and model of the building frame structure have also shown a new trend of multi-channel development. The vertical shape and plane layout of the building are becoming more and more complex, which has brought many new problems to the injured personnel of the building and put forward higher requirements for the damage analysis of multi-story buildings. The structural design of multi-story buildings adopts the form of frame structure, which can form a large internal space and can also carry out flexible building plane layout. Since the frame structure system is widely used in structural design, the damage analysis of frame structure buildings is particularly important. At the same time, some practical problems in the analysis process of multi-story building frame structure are often ignored, leaving safety hazards to the quality of construction projects.

[0005] Therefore, it is necessary to further research and develop new technologies for analyzing damage to buildings under the ground in order to improve work efficiency, reduce detection costs, and ensure the quality of analysis results. This can include optimizing building damage identification methods, clarifying building damage standards, simplifying building damage analysis steps, and quantifying building damage conditions.

[0006] In view of this, this patent application is proposed. Summary of the invention

[0007] The analysis method for tunnel side-penetrating frame-structured buildings based on foundation stress loss described in the present application aims to solve the problems existing in the above-mentioned prior art and proposes an analysis means to solve the potential damage caused to adjacent buildings when a shield tunnel side-penetrates an existing surface building, so as to simplify the building damage analysis steps, optimize the building damage identification method, clarify the building damage standards and quantify the building damage conditions, so as to achieve the purpose of achieving safe construction of tunnels and ensuring the safety and usability of surface buildings after disturbance.

[0008] To achieve the above design objectives, the tunnel side-penetrating frame structure building analysis method based on foundation stress loss includes the following implementation steps:

[0009] Step 1), simplify the building structure;

[0010] Structural simplification of frame buildings, including simplification of members, supports and nodes, and simplification of loads;

[0011] Step 2) Calculation of building foundation settlement;

[0012] The settlement of the building foundation is calculated by using the layered summation method. At the same time, due to the loss of foundation stress caused by tunnel excavation, the supporting effect of the surface soil on the foundation decreases, and the correction coefficient α is introduced into the foundation settlement calculation formula;

[0013] Step 3), surface settlement calculation;

[0014] The surface settlement line is calculated using the shield tunnel surface settlement formula, the maximum surface settlement S_max and the surface settlement trough width i are corrected, and correction coefficients β and γ are introduced;

[0015] Step 4), solve the internal forces of the building;

[0016] Conduct internal force analysis of surface frame structure buildings under displacement or deformation conditions;

[0017] Solve the internal forces of the building, including the axial force, shear force and bending moment of the structure, and only consider the main load-bearing structure to ensure the safety of the structure;

[0018] Assume that the maximum deformation is the vertical settlement S. Since the frame structure building is a rigid structure during construction, the settlement S includes the settlement of the foundation under the influence of the shield tunnel and the surface settlement, that is, S = S'(x) + s'; where x is the horizontal distance between the column on one side of the building close to the tunnel and the center line of the tunnel;

[0019] Step 5), building resistance-stress comparison;

[0020] Compare the building stress detected and analyzed with the building's own resistance and handle it according to the prescribed standards;

[0021] The structural safety factor η is used for rating, which is divided into four levels, with different levels corresponding to different tasks.

[0022] Furthermore, the step 1) simplifies the rods, including simplifying the beams and columns and replacing them with an axis line; simplifies the nodes, including simplifying the connections between the beams and columns and simplifying them into rigid connections; and simplifies the loads, including simplifying concentrated forces, uniformly distributed loads and bending moments.

[0023] Furthermore, in step 2), the calculation formula of the layered summation method is as follows:

[0024]

[0025] Where, s is the foundation settlement, unit is mm;

[0026] e 1i is the average value of the self-weight stress of the i-th layer (σ ci +σ c(i-1) ) / 2, and the corresponding porosity ratio is obtained from the ep curve;

[0027] e 2i is the average value of the self-weight stress of the i-th layer (σ ci +σ c(i-1) ) / 2 and the average value of additional stress (σ z\i +σ z(i-1) ) / 2), and the corresponding porosity ratio is obtained from the ep curve;

[0028] a i 、E si 、m vi are the compression coefficient, compression modulus and volume compression coefficient of the i-th layer of soil respectively;

[0029] After adding the correction coefficient α, the foundation settlement s′ after the foundation stress loss is obtained, that is, s′=αs;

[0030] Among them, α comes from the stress loss effect of the foundation caused by the disturbance of the shield tunnel under the condition of using the normal foundation settlement formula, and its value is 1+v l , v l is the ground loss rate of shield tunnel excavation, s′=(1+v l )s.

[0031] Furthermore, in step 3), first, the settlement value of any point on the ground is calculated according to the following Peck:

[0032]

[0033] Where S(x) is the settlement value of any point on the ground, in mm;

[0034] S max It is the maximum value of ground settlement, located at the symmetry center of the settlement curve (corresponding to the position of the tunnel axis), in mm;

[0035] x is the distance from the center of the settlement curve to the calculated point, in meters;

[0036] i is the distance from the symmetry center of the settlement curve to the inflection point (inflection point) of the curve, generally called the "settlement trough width", in meters;

[0037] Then, the coefficients α and β are introduced to correct the maximum settlement and the width of the sedimentation tank to obtain an accurate calculation structure, and the following formula is calculated:

[0038]

[0039] Furthermore, the calculation process of the introduced coefficients α and β is as follows:

[0040] First, we took the logarithm of the traditional Peck formula and performed regression analysis. is the constant term after regression, is the linear coefficient after regression, and we get:

[0041]

[0042] Then, the surface settlement monitoring data similar to the geological conditions of shield tunnel construction are selected and regression simulation is performed to obtain of taking Value, that is:

[0043] The above formula (3) and formula (4) are combined to calculate the specific values ​​of coefficients α and β.

[0044] Furthermore, the step 4) of calculating the internal force of building settlement caused by foundation stress includes the following steps:

[0045] 4.1) Determine the basic unknown quantities;

[0046] Add rigid arms to prevent rotation and support chains to prevent movement to the nodes of the original structure with angular displacement and linear displacement, and the sum of the number of additional rigid arms and additional support chains is the basic unknown quantity of the displacement method.

[0047] 4.2) Based on the condition that the sum of the constraint forces on the additional constraints is zero, the displacement method equation is established:

[0048] 4.3) When drawing a building, each additional constraint generates a unit displacement Δj =1 bending moment diagram And the bending moment diagram Mp under load, the coefficient k is calculated from the equilibrium condition ij and the free term F ip ;

[0049] 4.4) Solve the equation to find Δ j ;

[0050] 4.5) Calculate the bending moment at the rod end according to the superposition principle The internal forces of the simplified frame structure are calculated.

[0051] Furthermore, in step 5), the safety factor η is used to analyze the damage degree of the building and take reinforcement measures;

[0052] The calculation formula of safety factor η is η=R / (γ0S);

[0053] In the formula, R is the structural resistance, which refers to the ability of the structure or structural components to resist external forces without being damaged, including bending resistance, shear resistance, and axial resistance;

[0054] γ0 is an important coefficient of the structure. In order to improve the stability analysis, it is taken as 1.1 in the frame structure;

[0055] S is the action effect, which refers to the internal force of the structure caused by the vertical displacement caused by the loss of foundation stress, including bending moment M, shear force Q and axial force N, which are calculated by the above step 4);

[0056] The rating content includes: when η≥1.00, it means that the building has not been damaged or the damage is extremely insignificant, and no reinforcement measures are required;

[0057] When η≥0.95, it indicates that the building has been damaged, but it has not significantly affected the bearing capacity of the structure. In this case, you can choose not to take reinforcement measures, but you can choose to take repair measures for visual effects;

[0058] When η≥0.90, it indicates that the building has been damaged and has significantly affected the bearing capacity of the structure. At this time, reinforcement measures should be taken;

[0059] When η<0.90, it indicates that the building has been seriously damaged and has seriously affected the bearing capacity of the structure. At this time, reinforcement measures must be taken in time.

[0060] In summary, the above-mentioned analysis method of tunnel side-penetrating frame structure buildings based on foundation stress loss has the following advantages and beneficial effects:

[0061] 1. This application can significantly solve the problems of long operation cycle, difficult construction period control and deviation of analysis results in traditional civil building damage analysis. By optimizing the rating and process of damage analysis, improving the identification and treatment of damaged parts, and proposing more reliable damage analysis steps as a whole, it can meet the calculation stability and reliability of the damage analysis results of surface buildings when the shield tunnel construction disturbs the stratum and causes foundation stress loss. The standards are all national unified standards, and the results are strictly tested and analyzed to ensure that the accuracy meets the requirements.

[0062] 2. This application can effectively simplify the operation process, improve the efficiency and quality of analysis work, and ensure the normal progress of underground construction and the safe use of surface buildings.

[0063] 3. This application proposes an optimized analysis process, which can effectively reduce equipment costs and reduce manpower and resource consumption during the construction process.

[0064] 4. This application is applicable to the field of building damage assessment and has the possibility of being expanded to other underground construction projects, including but not limited to underground parking facilities and underground commercial centers. It has broad application prospects and economic benefits and is of great significance in the construction and renovation of subway tunnels. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] The present application is now further described in conjunction with the following drawings;

[0066] Figure 1 This is a schematic diagram of an underground tunnel passing through a frame structure building;

[0067] Figure 2 This is a simplified diagram of the frame structure;

[0068] Figure 3 This is a schematic diagram of building settlement deformation;

[0069] Figure 4 It is a schematic diagram of the overall structural deformation;

[0070] Figure 5-1 It is a schematic diagram of the forces on the building foundation before shield tunnel excavation;

[0071] Figure 5-2 It is a schematic diagram of the influence of ground settlement on the force of building foundation;

[0072] Figure 6 Simplified schematic diagram for loads;

[0073] Figure 7 Calculation diagram for building settlement and deformation;

[0074] In the above figures, 1- soil layer information example; 2- frame structure building; 3- pile foundation; 4- ground surface; 5- tunnel construction location;

[0075] 11- simplified beams and columns; 12- simplified nodes; 13- simplified ground surface; DETAILED DESCRIPTION

[0076] In order to further explain the technical means adopted by the present application to achieve the predetermined design objectives, the following preferred implementation scheme is proposed in conjunction with the accompanying drawings.

[0077] In the following description, specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in a variety of other ways than those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0078] Embodiment 1, as Figures 1 to 7 As shown, the tunnel side-penetrating frame structure building analysis method based on foundation stress loss described in this application is intended to clarify the building damage standard and quantify the identification and analysis results.

[0079] The frame structure is a building structure composed of many beams and columns to bear the entire load of the building. In existing high-rise civil buildings and multi-story industrial plants, brick walls can no longer bear heavy loads, and frames are often used as load-bearing structures.

[0080] Whether the shield tunnel passes through a building directly or sideways, it will cause surface subsidence. Once the ground subsidence exceeds the prescribed safety range, appropriate treatment measures must be taken immediately.

[0081] like Figure 3 As shown in Figure 1, when a shield tunnel passes through a building, the ground tilt deformation is usually concentrated in the area above the excavation working surface in the cross section and longitudinal section of the tunnel construction. This tilt is caused by the loss of original support of the soil during the tunnel excavation process, which leads to the movement and redistribution of the surrounding soil, thus causing uneven settlement of the ground surface.

[0082] When the ground tilts, the buildings above it will also tilt. This tilt will cause the building's own weight to have an eccentric effect, which will in turn produce additional overturning moments on the building's structure. This moment may threaten the structural stability of the building, especially under external dynamics such as earthquakes or strong winds. At the same time, the load-bearing structure of the building will also produce additional stresses due to the tilt of the ground. These stresses may cause the force transmission path inside the building to change, causing a redistribution of the foundation reaction force. This redistribution may cause excessive stress concentration in some areas and insufficient support in other areas.

[0083] During subway tunnel excavation, the ground may be disturbed, which not only affects the surrounding soil, but also changes the stress and strain field near the tunnel, resulting in ground settlement. These changes may extend below the foundation of adjacent buildings, then transfer from the foundation to the foundation, and then transfer upward to the structure, thereby inducing secondary internal forces and deformations in the structure.

[0084] like Figure 5-1 As shown, when the shield tunnel is not under construction, the building is in a stable state, and the foundation stress is the reaction force generated by the gravity and load applied to the landmark by the earth supporting the building.

[0085] like Figure 5-2 As shown in the figure, after the shield tunnel construction of the building, the ground settlement occurs, causing the ground that originally generated the foundation stress to sink and lose its support for the building, thus causing the foundation stress loss. The uneven settlement of the ground causes the building to be partially suspended, and the building will sink and deform due to its own gravity, and then reach stress balance again.

[0086] In order to implement damage calculation for frame structure buildings based on foundation stress loss during tunnel side crossing construction, the analysis method described in this application includes the following implementation steps:

[0087] Step 1), simplify the building structure;

[0088] Structural simplification of frame buildings, including simplification of members, supports and nodes, and simplification of loads;

[0089] The connection between the earth and the building structure foundation, and between the building structure foundation and the building superstructure are set as rigid connections respectively, so that the earth, the building foundation and the superstructure are connected as an integral structure in subsequent analysis and calculation, so as to facilitate analysis and calculation;

[0090] Specifically, considering that the forces on the system are usually spatially coordinated, for the convenience of analysis, the directions with insignificant coupling are considered separately and simplified into a plane structure. At the same time, the main structures bearing the force of the frame structure are beams and columns, so an ideal calculation model is used to replace the actual structure to omit the structure for which the exact solution of the problem is not necessary in the project.

[0091] like Figure 1 and Figure 2 As shown, the compressive stiffness (EA), flexural stiffness (EI), and shear stiffness (GA) of each component are obtained by investigating the drawings or calculating;

[0092] Simplification of rods, including beams and columns, is only applicable when L / H>8 is met to ensure accuracy (this standard is the simplification standard of structural mechanics, L is the length of the rod, H is the width of the rod). After simplification, an axis is used to replace it.

[0093] The simplification of nodes is to simplify the connection between beams and columns. Since it needs to withstand bending moments and forces in all directions in the frame structure, it is simplified into a rigid connection.

[0094] like Figure 6 As shown, the simplification of loads includes simplification of concentrated force, uniformly distributed load, and bending moment;

[0095] Step 2) Calculation of building foundation settlement;

[0096] Including calculation of uneven settlement of surface buildings before tunnel excavation;

[0097] The settlement of the building foundation is calculated by using the layered summation method. At the same time, due to the loss of foundation stress caused by tunnel excavation, the supporting effect of the surface soil on the foundation decreases, and the correction coefficient α is introduced into the foundation settlement calculation formula;

[0098] The calculation formula of the stratified sum method is as follows:

[0099]

[0100] Where, s is the foundation settlement, unit is mm;

[0101] e 1i is the average value of the self-weight stress of the i-th layer (σ ci +σ c(i-1) ) / 2, and the corresponding porosity ratio is obtained from the ep curve;

[0102] e 2i is the average value of the self-weight stress of the i-th layer (σ ci +σ c(i-1) ) / 2 and the average value of additional stress (σ z\i +σ z(i-1) ) / 2), and the corresponding porosity ratio is obtained from the ep curve;

[0103] a i 、E si 、m vi are the compression coefficient, compression modulus and volume compression coefficient of the i-th layer of soil respectively;

[0104] After adding the correction coefficient α, the foundation settlement s′ after the foundation stress loss is obtained, that is, s′=αs;

[0105] Among them, α comes from the stress loss effect of the foundation caused by the disturbance of the shield tunnel under the condition of using the normal foundation settlement formula, and its value is 1+v l , v l is the ground loss rate of shield tunnel excavation, s′=(1+v l )s;

[0106] The ground loss caused by shield construction and the disturbance of the soil around the shield, or the remodeling and reconsolidation caused by shear damage, are the basic causes of ground subsidence. The ground loss rate, also known as the ground damage rate or ground erosion rate, is an important indicator to characterize soil settlement, ground sliding and ground loss during shield construction. It refers to the ratio of the sum of ground areas with deformation characteristics such as ground sliding to the total ground area. The ground loss rate is an important parameter to characterize the changes in geological background, an important indicator for evaluating geological disasters, and an important indicator for judging geological complexity and resource availability. Introducing the ground loss rate into the calculation of building foundation settlement can accurately take into account the impact of shield construction. Since the frame structure foundation and the upper building are simplified as rigid connections, the foundation settlement will be included in the overall settlement of the building, and the calculation result will be used in the subsequent calculation of the overall settlement of the building.

[0107] Step 3), surface settlement calculation;

[0108] The surface settlement line is calculated using the shield tunnel surface settlement formula, the maximum surface settlement S_max and the surface settlement trough width i are corrected, and correction coefficients β and γ are introduced to improve the calculation accuracy for specific working conditions;

[0109] First, calculate the settlement value of any point on the ground according to the following Peck:

[0110]

[0111] Where S(x) is the settlement value of any point on the ground, in mm;

[0112] S max It is the maximum value of ground settlement, located at the symmetry center of the settlement curve (corresponding to the position of the tunnel axis), in mm;

[0113] x is the distance from the center of the settlement curve to the calculated point, in meters;

[0114] i is the distance from the symmetry center of the settlement curve to the inflection point (inflection point) of the curve, generally called the "settlement trough width", in meters;

[0115] The coefficients α and β are introduced to correct the maximum settlement and the width of the sedimentation tank to obtain an accurate calculation structure, and the following formula is obtained:

[0116]

[0117] The following is the calculation process of coefficients α and β:

[0118] First, we took the logarithm of the traditional Peck formula and performed regression analysis. is the constant term after regression, is the linear coefficient after regression, and we get:

[0119]

[0120] Select the surface settlement monitoring data with similar geological conditions to the shield tunnel construction and perform regression simulation to obtain The value of is:

[0121] Combine the above formula (3) with formula (4) to calculate the specific values ​​of coefficients α and β;

[0122] Step 4), solve the internal forces of the building;

[0123] Conduct internal force analysis of surface frame structure buildings under displacement or deformation conditions;

[0124] Solve the internal forces of the building, including the axial force, shear force and bending moment of the structure, and only consider the main load-bearing structure to ensure the safety of the structure;

[0125] Specifically, because the most serious deformation of the building superstructure caused by the side passage of the tunnel is the structure on the side close to the tunnel, the maximum deformation is assumed to be the vertical settlement S;

[0126] Since the frame structure building is a rigid structure during construction, the settlement S includes the settlement of the foundation under the influence of the shield tunnel and the surface settlement, that is, S = S'(x) + s'; where x is the horizontal distance between the column on the side of the building close to the tunnel and the center line of the tunnel;

[0127] The calculation of internal forces of building settlement caused by foundation stress includes the following steps:

[0128] 4.1) Determine the basic unknown quantities;

[0129] Add rigid arms to prevent rotation and support chains to prevent movement to the nodes of the original structure with angular displacement and linear displacement, and the sum of the number of additional rigid arms and additional support chains is the basic unknown quantity of the displacement method.

[0130] 4.2) Based on the condition that the sum of the constraint forces on the additional constraints is zero, the displacement method equation is established:

[0131] 4.3) When drawing a building, each additional constraint generates a unit displacement Δ j=1 bending moment diagram And the bending moment diagram Mp under load, the coefficient k is calculated from the equilibrium condition ij and the free term F ip ;

[0132] 4.4) Solve the equation to find Δ j ;

[0133] 4.5) Calculate the bending moment at the rod end according to the superposition principle To calculate the simplified internal forces of the frame structure;

[0134] Step 5), building resistance-stress comparison;

[0135] Compare the building stress detected and analyzed with the building's own resistance and handle it according to the prescribed standards;

[0136] The structural safety factor η is used for rating, which is divided into four levels, with different levels corresponding to different tasks.

[0137] The safety factor η is used to analyze the degree of damage to the building and take reinforcement measures.

[0138] The calculation formula of safety factor η is η=R / (γ0S);

[0139] In the formula, R is the structural resistance, which refers to the ability of the structure or structural components to resist external forces without being damaged, including bending resistance, shear resistance, and axial resistance;

[0140] γ0 is an important coefficient of the structure. In order to improve the stability analysis, it is taken as 1.1 in the frame structure;

[0141] S is the action effect, which refers to the internal force of the structure caused by the vertical displacement caused by the loss of foundation stress, including bending moment M, shear force Q and axial force N, which are calculated by the above step 4);

[0142] The rating content includes: when η≥1.00, it means that the building has not been damaged or the damage is extremely insignificant, and no reinforcement measures are required;

[0143] When η≥0.95, it indicates that the building has been damaged, but it has not significantly affected the bearing capacity of the structure. In this case, you can choose not to take reinforcement measures, but you can choose to take repair measures for visual effects;

[0144] When η≥0.90, it indicates that the building has been damaged and has significantly affected the bearing capacity of the structure. At this time, reinforcement measures should be taken;

[0145] When η<0.90, it indicates that the building has been seriously damaged and has seriously affected the bearing capacity of the structure. At this time, reinforcement measures must be taken in time.

[0146] As described above, similar technical solutions can be derived from the solutions given in the drawings and descriptions. However, any solution content that does not deviate from the structure of the present invention still belongs to the scope of rights of the technical solution of this application.

Claims

1. A method for analyzing a tunnel side-penetrating frame structure building based on foundation stress loss, characterized in that: The implementation steps include: Step 1), simplify the building structure; Structural simplification of frame buildings, including simplification of members, supports and nodes, and simplification of loads; Step 2) Calculation of building foundation settlement; The settlement of the building foundation is calculated by using the layered summation method. At the same time, due to the loss of foundation stress caused by tunnel excavation, the supporting effect of the surface soil on the foundation decreases, and the correction coefficient α is introduced into the foundation settlement calculation formula; Step 3), surface settlement calculation; The surface settlement line is calculated using the shield tunnel surface settlement formula, the maximum surface settlement S_max and the surface settlement trough width i are corrected, and correction coefficients β and γ are introduced; Step 4), solve the internal forces of the building; Conduct internal force analysis of surface frame structure buildings under displacement or deformation conditions; Solve the internal forces of the building, including the axial force, shear force and bending moment of the structure, and only consider the main load-bearing structure to ensure the safety of the structure; Assume that the maximum deformation is the vertical settlement S. Since the frame structure building is a rigid structure during construction, the settlement S includes the settlement of the foundation under the influence of the shield tunnel and the surface settlement, that is, S = S'(x) + s'; where x is the horizontal distance between the column on one side of the building close to the tunnel and the center line of the tunnel; Step 5), building resistance-stress comparison; Compare the building stress detected and analyzed with the building's own resistance and handle it according to the prescribed standards; The structural safety factor η is used for rating, which is divided into four levels, with different levels corresponding to different tasks.

2. The method for analyzing a tunnel side-penetrating a frame structure building based on foundation stress loss according to claim 1 is characterized by: The step 1) simplifies the rods, including simplifying the beams and columns and replacing them with an axis line; simplifies the nodes, including simplifying the connections between the beams and columns and simplifying them into rigid connections; and simplifies the loads, including simplifying the concentrated forces, uniformly distributed loads and bending moments.

3. The method for analyzing a tunnel side-penetrating a frame structure building based on foundation stress loss according to claim 1, characterized in that: In the step 2), the calculation formula of the layered summation method is as follows: Where, s is the foundation settlement, unit is mm; e 1i is the average value of the self-weight stress of the i-th layer (σ ci +σ c(i -1)) / 2, and the corresponding porosity ratio is obtained from the ep curve; e 2i is the average value of the self-weight stress of the i-th layer (σ ci +σ c(i -1)) / 2 and the average value of additional stress (σ z\i +σ z(i-1) ) / 2), and the corresponding porosity ratio is obtained from the ep curve; a i 、E si 、m vi are the compression coefficient, compression modulus and volume compression coefficient of the i-th layer of soil respectively; After adding the correction coefficient α, the foundation settlement s′ after the foundation stress loss is obtained, that is, s′=αs; Among them, α comes from the stress loss effect of the foundation caused by the disturbance of the shield tunnel under the condition of using the normal foundation settlement formula, and its value is 1+v l , v l is the ground loss rate of shield tunnel excavation, s′=(1+v l )s.

4. The method for analyzing a tunnel side-penetrating a frame structure building based on foundation stress loss according to claim 1, characterized in that: The step 3), First, calculate the settlement value of any point on the ground according to the following Peck: Where S(x) is the settlement value of any point on the ground, in mm; S max It is the maximum value of ground settlement, located at the symmetry center of the settlement curve (corresponding to the position of the tunnel axis), in mm; x is the distance from the center of the settlement curve to the calculated point, in meters; i is the distance from the symmetry center of the settlement curve to the inflection point (inflection point) of the curve, generally called "sedimentation trough width", in meters; Then, the coefficients α and β are introduced to correct the maximum settlement and the width of the sedimentation tank to obtain an accurate calculation structure, and the following formula is calculated:

5. The method for analyzing a tunnel side-penetrating a frame structure building based on foundation stress loss according to claim 4 is characterized by: The calculation process of the introduced coefficients α and β is as follows: First, we took the logarithm of the traditional Peck formula and performed regression analysis. is the constant term after regression, is the linear coefficient after regression, and we get: Then, the surface settlement monitoring data similar to the geological conditions of shield tunnel construction are selected and regression simulation is performed to obtain The value of is: The above formula (3) and formula (4) are combined to calculate the specific values ​​of coefficients α and β.

6. The method for analyzing a tunnel side-penetrating a frame structure building based on foundation stress loss according to claim 1, characterized in that: The step 4) of calculating the internal force of building settlement caused by foundation stress includes the following steps: 4.1) Determine the basic unknown quantities; Add rigid arms to prevent rotation and support chains to prevent movement to the nodes of the original structure with angular displacement and linear displacement, and the sum of the number of additional rigid arms and additional support chains is the basic unknown quantity of the displacement method. 4.2) Based on the condition that the sum of the constraint forces on the additional constraints is zero, the displacement method equation k is established ij Δ j +F iP =0(i,j=1,2,…,n); 4.3) When drawing a building, each additional constraint generates a unit displacement Δ j =1 bending moment diagram And the bending moment diagram Mp under load, the coefficient k is calculated from the equilibrium condition ij and the free term F ip ; 4.4) Solve the equation to find Δ j ; 4.5) Calculate the bending moment at the rod end according to the superposition principle The internal forces of the simplified frame structure are calculated.

7. The method for analyzing a tunnel side-penetrating a frame structure building based on foundation stress loss according to claim 1, characterized in that: In step 5), a safety factor η is used to analyze the damage degree of the building and take reinforcement measures; The calculation formula of safety factor η is η=R / (γ0S); In the formula, R is the structural resistance, which refers to the ability of the structure or structural components to resist external forces without being damaged, including bending resistance, shear resistance, and axial resistance; γ0 is an important coefficient of the structure. In order to improve the stability analysis, it is taken as 1.1 in the frame structure; S is the action effect, which refers to the internal force of the structure caused by the vertical displacement caused by the loss of foundation stress, including bending moment M, shear force Q and axial force N, which are calculated by the above step 4); Rating content includes: When η≥1.00, it indicates that the building has not been damaged or the damage is extremely insignificant, and no reinforcement measures are required; When η≥0.95, it indicates that the building has been damaged, but it has not significantly affected the bearing capacity of the structure. In this case, you can choose not to take reinforcement measures, but you can choose to take repair measures for the sake of visual effect; When η≥0.90, it indicates that the building has been damaged and has significantly affected the bearing capacity of the structure. At this time, reinforcement measures should be taken; When η<0.90, it indicates that the building has been seriously damaged and has seriously affected the bearing capacity of the structure. At this time, reinforcement measures must be taken in time.

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