Structural analysis and design method adopting border reverse construction method

Abstract

The invention relates to the technical field of civil engineering, in particular to a structural analysis and design method adopting a border reverse construction method, and solves the problem of how to obtain a specific reinforcement scheme. The method comprises the steps that a construction area is divided based on preset conditions, and a reverse operation border area and a consequent operation center area are obtained; a floor unit is simplified into a rod piece unit, soil side pressure forms a uniform load to act on the rod piece unit, and the stress condition of the rod piece unit is obtained through analysis; establishing a two-dimensional model of a floor slab in a reverse operation border area, and applying soil side pressure to the periphery of the two-dimensional model to obtain analyzed unit stress and strain; establishing a three-dimensional model of the floor slab of the reverse operation border area to obtain overall structure performance information and corresponding component reinforcement information; a four-dimensional model considering the combined action of the soil and the main body structure is established, and construction simulation analysis of the whole process is carried out; and comparing the obtained analysis results, and adjusting the component reinforcement based on the comparison result. According to the method, the reinforcement scheme meeting the construction requirements can be obtained.

Description

Technical Field

[0001] The invention relates to the technical field of civil engineering, and specifically provides a structural analysis and design method using an edge zone inverse method. Background Art

[0002] With the steady improvement of my country's economy and the rapid growth of urban population, the demand for urban infrastructure will also increase. In order to make more effective use of limited urban land resources, the rapid development of high-rise and super-high-rise buildings has become an inevitable trend. At the same time, the development and utilization of underground space has gradually attracted people's attention, and foundation pit projects will also increase day by day.

[0003] The existing construction methods of foundation pit engineering are mainly divided into the forward construction method and the reverse construction method, but both have some problems in foundation pit engineering: the temporary components in the forward construction method have limited stiffness as the retaining structure, which is easy to cause large deformation of the foundation pit; during the dismantling process, the retaining structure may also have internal force and deformation mutations, increasing the construction risk, which has a great impact on the foundation pit around the target project, and the abandoned temporary components do not meet the environmental protection requirements; the traditional reverse construction method has solved the problems of the forward construction method to a certain extent, but it is extremely inconvenient to use the reverse construction method in the high-rise core tube basement area. At present, the following two methods are generally used: one is to use densely packed square steel tube concrete columns as the vertical bearing capacity components of the core tube basement area, and set conversion components through the reference layer to replace the shear wall above. However, this method needs to consider the connection problem between steel tube concrete columns, which will have a certain impact on the overall performance of the core tube part; the second is to use ground-connected walls as the vertical bearing capacity components of the core tube basement area, but this method is expensive, and it is difficult to meet the requirements of shear walls in terms of construction quality, strength and durability. At the same time, excessive wall thickness will also affect the building layout.

[0004] In order to solve the problems existing in the traditional sequential construction method and the traditional reverse construction method, an improved local reverse construction method - the edge area reverse construction method came into being. This method aims to ensure the stability of the core tube structure, while greatly reducing the amount of temporary support engineering, improving the excavation efficiency and construction speed. At the same time, the large opening design in the central area also significantly improves the lighting and illumination conditions during the reverse construction process in the edge area. However, there is currently a lack of specific analysis and design processes on how to scientifically divide the scope of the reverse construction edge area and the sequential construction center area. After the scope is demarcated, how to ensure that the annular floor slab formed in the reverse construction edge area has a certain strength and rigidity to ensure the stability of the foundation pit, and how to obtain a specific reinforcement scheme to meet construction needs have become urgent problems to be solved. Summary of the invention

[0005] The present invention aims to solve the above technical problems, namely, at least one of the problems of how to scientifically divide the scope of the reverse-construction side area and the forward-construction central area, how to ensure the strength and stiffness of the annular floor slab formed in the reverse-construction side area, and how to obtain a specific reinforcement scheme.

[0006] In a first aspect, the present invention provides a structural analysis and design method using an edge region inversion method, the structural analysis and design method comprising:

[0007] S1. Perform preliminary structural arrangement on the construction area, divide the construction area based on preset conditions, and obtain the initial reverse construction side area and forward construction center area;

[0008] S2. For the basement part of the top-down construction edge area, simplify the floor unit into a rod unit, convert the soil side pressure in proportion to form a uniformly distributed load acting on the rod unit, and analyze the force condition on the rod unit;

[0009] S3, establishing a two-dimensional model of the floor slab in the reverse construction edge area, adding the soil side pressure calculated in step S2 to its periphery, and obtaining the unit stress and strain of the analysis;

[0010] S4, establishing a three-dimensional model of the floor slab in the reverse construction edge area, modifying component parameters in a preset manner, and obtaining overall structural performance information and corresponding component reinforcement information;

[0011] S5. Establish a four-dimensional model that takes into account the interaction between soil and main structure, and conduct construction simulation analysis of the entire process;

[0012] S6. Compare the analysis result obtained in step S5 with the analysis results obtained in steps S3 and S4, and selectively adjust the reinforcement information of the component based on the comparison result.

[0013] In some feasible implementations of the above-mentioned structural analysis and design method, the preset conditions include a first condition and a second condition; the first condition includes: the basement part of the core tube belongs to the forward construction central area, and the rest belongs to the reverse construction side area; the second condition includes: the width of the floor slab of the reverse construction side area is greater than or equal to 10m, and is at least greater than or equal to 1 / 6 of the side length corresponding to the forward construction central area.

[0014] In some feasible implementations of the above structural analysis and design method, the preset conditions also include:

[0015] The basement of the high-rise tower of the core tube belongs to the forward construction central area, and if the column position of the high-rise tower is within the range of the second condition, the column position of the high-rise tower belongs to the reverse construction side area; and / or

[0016] If the podium basement adopts reinforced concrete columns, the podium basement belongs to the forward construction central area; if the podium basement adopts steel tube concrete columns or under the second condition, the podium basement belongs to the reverse construction edge area.

[0017] In some feasible implementations of the above structural analysis and design method, step S2 includes:

[0018] If the side length of the floor unit is less than 1 / 5 of the maximum side length of the longitudinal center area, the floor unit is not taken into consideration when simplifying the floor unit to the bar unit; and / or

[0019] The length of the rod unit is half of the sum of the side length of the corresponding forward-working center area and the side length of the corresponding reverse-working side area.

[0020] In some feasible implementations of the above structural analysis and design method, after obtaining the analyzed unit stress and strain, step S3 further includes:

[0021] Determine whether the unit stress is greater than or equal to the design strength of concrete. If so, increase the floor width of the reverse edge area until the unit stress is less than or equal to the design strength of concrete.

[0022] In some feasible implementations of the above-mentioned structural analysis and design method, the "modifying component parameters in a preset manner" includes: comparing the stress results of each floor slab of the three-dimensional model with the analysis results of step S2 and the analysis results of step S3, and modifying the component parameters according to the comparison results.

[0023] In some feasible implementations of the above structural analysis and design method, after establishing a four-dimensional model that takes into account the interaction between soil and the main structure and performing a full-process construction simulation analysis, the structural analysis and design method further includes:

[0024] The analysis results obtained in step S5 are compared with the analysis results obtained in steps S2 and S3 respectively, and the analysis results in step S2 are used as a guide to find out the unfavorable stress points and optimize the structural design.

[0025] In some feasible implementations of the above structural analysis and design method, the “selectively adjusting the component reinforcement information based on the comparison result” includes:

[0026] If the floor stress in step S5 is greater than or equal to the corresponding floor stress in step S3, and the absolute value of the difference between the two is less than or equal to 30% of the floor stress in step S3, the analysis results obtained in steps S4 and S5 are used to perform envelope reinforcement design; or

[0027] If the floor stress in step S5 is less than or equal to the corresponding floor stress in step S3, and the absolute value of the difference between the two is less than or equal to 20% of the floor stress in step S3, the analysis results obtained in steps S4 and S5 are used to perform envelope reinforcement design; or

[0028] If the absolute value of the difference between the floor stress in step S5 and the corresponding floor stress in step S4 is less than or equal to 10% of the floor stress in step S4, the analysis results obtained in steps S4 and S5 are used to perform envelope reinforcement design.

[0029] In some feasible implementations of the above structural analysis and design method, the “selectively adjusting the reinforcement of the component based on the comparison result” also includes:

[0030] If the floor stress in step S5 is less than or less than or equal to the corresponding floor stress in step S3, and the absolute value of the difference between the two is greater than or greater than or equal to 20% of the floor stress in step S3, and the absolute value of the difference between the floor stress in step S5 and the corresponding floor stress in step S4 is greater than or greater than 10% of the floor stress in step S4, the analysis results obtained in steps S2, S3, S4 and S5 are used to perform comprehensive envelope reinforcement design.

[0031] In some feasible implementations of the above structural analysis and design method, the "using the analysis results obtained in step S2, step S3, step S4 and step S5 to perform comprehensive envelope reinforcement" includes:

[0032] The analysis result obtained in step S4 is used as the main basis, and the analysis results obtained in steps S2, S3 and S5 are used as auxiliary references. In the uncertain places, the envelope reinforcement design is performed according to the analysis results obtained in steps S2, S3 and S5.

[0033] The above one or more technical solutions of the present invention have at least one or more of the following Beneficial effects:

[0034] (1) Based on the preset conditions, the construction area is divided into areas, which can optimize the division range of the reverse construction side area and the normal construction side area, ensuring that the annular floor slab formed in the side area after the division can form an integral enclosure structure with the supporting structure, and at the same time ensure that the annular floor slab formed in the reverse construction side area has a certain strength and rigidity, thereby ensuring the stability of the foundation pit;

[0035] (2) By carrying out one-dimensional analysis, two-dimensional analysis, three-dimensional analysis, and time-space four-dimensional analysis on the basement part of the reverse construction edge area, we can fully and deeply understand the mechanical behavior of this area in different dimensions. Based on the comparison results of these multi-dimensional analyses, the reinforcement design of the basement components can be accurately adjusted to obtain a specific reinforcement scheme that not only meets the actual construction needs but also ensures the safety and stability of the structure. This comprehensive analysis method not only improves the scientificity and accuracy of the design, but also provides strong support for quality control and safety management during the construction process. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings, in which:

[0037] Figure 1 A flowchart of a structural analysis and design method using an edge area inverse method provided in Example 1 of the present invention;

[0038] Figure 2 It is a schematic diagram of the present invention performing a one-dimensional analysis on the basement part of the reverse-work side zone;

[0039] Figure 3 It is a schematic diagram of the present invention performing a two-dimensional analysis on the basement part of the reverse-work side zone;

[0040] Figure 4 It is a schematic diagram of the present invention performing a three-dimensional analysis on the basement part of the reverse-planting edge area;

[0041] Figure 5 This is a schematic diagram of the present invention performing a time-space four-dimensional analysis on the basement portion of the reverse-working edge area. DETAILED DESCRIPTION

[0042] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not used to limit the scope of protection of the present invention. Those skilled in the art can make adjustments as needed to adapt to specific applications. In order to better illustrate the present invention, numerous specific details are given in the specific embodiments below. It should be understood by those skilled in the art that the present invention can also be implemented without certain specific details.

[0043] Example 1

[0044] like Figure 1 As shown, Figure 1 1 is a schematic flow chart of the main steps of a structural analysis and design method using the edge area inverse method provided by the present invention. The structural analysis and design method using the edge area inverse method provided by the present invention includes:

[0045] S1. Perform preliminary structural arrangement on the construction area, divide the construction area based on preset conditions, and obtain the initial reverse construction side area and forward construction center area;

[0046] It should be noted that a preliminary structural layout is carried out in the construction area, including the arrangement of column grids, the location of the core tube shear wall part, the location of the tower and podium part, the preliminary determination of the column type, the thickness of the floor slab, etc. The forward construction center area refers to the area where the forward construction method is used for construction, which is usually located in the center of the foundation pit. The forward construction center area can ensure the smooth excavation of the foundation pit and provide stable support for the subsequent underground structure construction through the forward construction method. The reverse construction edge area refers to the area where the reverse construction method is used for construction, which is usually located at the periphery or edge of the foundation pit. The reverse construction edge area can reduce the impact of the foundation pit excavation on the surrounding environment, improve construction safety, and shorten the construction period through the reverse construction method.

[0047] The preset conditions include a first condition and a second condition.

[0048] The first condition includes: the basement part of the core tube is classified as the central area of ​​the construction, and the rest is classified as the side area of ​​the reverse construction. Since the core tube is an important supporting structure of the building, the construction quality and stability of its basement part are crucial. By classifying it as the central area of ​​the construction, that is, the basement part of the core tube is constructed by the construction method, a stable structural system can be gradually constructed, providing a solid foundation for subsequent construction, which helps to enhance the structural stability of the entire building and ensure construction safety and quality.

[0049] The second condition includes: the width of the floor slab in the reverse-built side area is greater than or equal to 10m, and at least greater than or equal to 1 / 6 of the corresponding side length of the sequential-built center area. The wider floor slab ensures that the floor slab has sufficient width to disperse the load, which can more effectively resist the horizontal and vertical loads, reduce structural deformation, and thus enhance the stability of the overall structure. The ratio requirement between the floor slab width of the reverse-built side area and the corresponding side length of the sequential-built center area ensures that the structural connection between the reverse-built side area and the sequential-built center area has a certain degree of coordination. By maintaining an appropriate proportional relationship, it can be ensured that the reverse-built side area can work together with the sequential-built center area when bearing loads to form a stable structural system.

[0050] On the basis of the above, the preset conditions also include: the basement of the high-rise tower of the core tube generally belongs to the central area of ​​the forward construction. If the column position of the high-rise tower is within the scope of the second condition, the column position of the high-rise tower belongs to the reverse construction side area. Under the second condition, the column position of the high-rise tower is attributed to the reverse construction side area, which can make the high-rise tower column adapt to the structure of the reverse construction side area, ensure that the connection between the high-rise tower column and the surrounding structure is more stable and reliable, thereby improving the overall structure's ability to resist lateral forces and overturning.

[0051] Furthermore, the preset conditions also include: if the podium basement adopts reinforced concrete columns, the podium basement belongs to the central area of ​​the construction. The construction of the construction method is usually carried out layer by layer from top to bottom. As the main load-bearing structure, the reinforced concrete column can adapt well to this construction sequence. After the reinforced concrete column is poured, it has good stability and bearing capacity, can support the weight of the upper structure, and resist various loads. Therefore, the podium basement adopting reinforced concrete columns generally belongs to the central area of ​​the construction method.

[0052] Furthermore, if the podium basement uses steel tube concrete columns, the podium basement belongs to the reverse construction edge area. Steel tube concrete columns have a high bearing capacity due to the combined effect of steel tubes and concrete, and can well adapt to the needs of foundation pit excavation and support in reverse construction. When reverse construction allows structural construction layer by layer from bottom to top, the construction of steel tube concrete columns can be carried out simultaneously with foundation pit excavation and support, thereby shortening the construction period. Therefore, the podium basement using steel tube concrete columns usually belongs to the reverse construction edge area.

[0053] Furthermore, if the podium basement meets the second condition, the podium basement belongs to the reverse construction side area. When the floor width of the reverse construction side area is large enough (greater than or equal to 10m), it can provide stronger horizontal support force, which helps to resist the lateral pressure generated during the foundation pit excavation process. In this case, the podium basement is classified as the reverse construction side area, which can make the structure of the podium basement more closely connected with the overall structure of the reverse construction side area, thereby enhancing the stability and lateral force resistance of the overall structure.

[0054] In the present invention, the construction area is divided based on the above-mentioned preset conditions, which can optimize the division range of the reverse construction side area and the normal construction side area, ensure that the annular floor slab formed in the side area after the division of the range can form an integral enclosure structure with the supporting structure, and at the same time ensure that the annular floor slab formed in the reverse construction side area has a certain strength and rigidity, thereby ensuring the stability inside the foundation pit.

[0055] S2. Please refer to Figure 2 In this embodiment, a one-dimensional analysis is performed on the basement part of the reverse construction edge area. Specifically, for the basement part of the reverse construction edge area, the floor unit is simplified into a rod unit, and the soil side pressure is converted proportionally to form a uniformly distributed load acting on the simplified rod unit, and the force condition on the rod unit is obtained through structural mechanics force analysis. For example, the soil side pressure can be calculated by over-excavation depth using known geological survey data, and applied to the simplified rod unit to analyze the projection direction where the maximum stress should appear and the projection direction where the maximum deformation should appear.

[0056] In one-dimensional analysis, by simplifying the floor unit into a bar unit, the amount of calculation can be reduced, the calculation process can be simplified, and the analysis efficiency can be improved. Although it has been simplified, the force analysis based on structural mechanics can still accurately reflect the force conditions of the bar unit, which helps engineers to evaluate and optimize the structure more accurately during the design stage to ensure the safety and stability of the structure.

[0057] It should be noted that the calculation method of soil side pressure should be calculated according to the specification, and over-excavation and the soil side pressure generated by it should be considered, and the two sides of the rod unit should be considered as fixed ends. Through one-dimensional analysis, the approximate stress condition of the floor slab can be estimated, and the projection direction of the maximum stress in the floor slab in the reverse construction area can be directly obtained, and the correctness of the subsequent three-dimensional and four-dimensional analysis and design results can be conceptually judged.

[0058] Furthermore, step S2 also includes: if the side length of the floor unit is less than 1 / 5 of the maximum side length of the center area, the floor unit is not taken into consideration when simplifying the floor unit to a rod unit. Since when the side length of the floor unit is small, especially when it is much smaller than the maximum side length of the center area, its contribution (such as stiffness, bearing capacity, etc.) in the actual structure may be relatively small, ignoring the small-sized floor unit can simplify the calculation model, reduce the amount of calculation, and make the analysis more focused on the main structural components, thereby improving the accuracy of the analysis.

[0059] Furthermore, step S2 also includes: the length of the rod unit is half of the sum of the side length of the corresponding forward-construction center area and the side length of the corresponding reverse-construction side area. During the reverse-construction construction process, the structures of the forward-construction center area and the reverse-construction side area will affect each other, jointly bear the load and deform, and setting the length of the rod unit to half of the sum of the side lengths of the two can reflect this deformation coordination to a certain extent, so that the analysis model is more consistent with the stress state of the actual structure.

[0060] S3. Please refer to Figure 3 In this embodiment, a two-dimensional analysis is performed on the basement part of the reverse construction edge area. Specifically, a two-dimensional model of the floor slab of the reverse construction edge area is established, and the soil side pressure calculated by the one-dimensional analysis in step S2 is added around it to obtain the unit stress and strain of the analysis.

[0061] In two-dimensional analysis, by simulating the effect of soil side pressure on the floor, the bearing capacity and deformation of the floor under actual soil pressure can be evaluated, thereby ensuring the safety of the structure. Analyzing unit stress and strain can reveal the stress distribution inside the floor, help to find potential stress concentration areas and weak links, and provide a basis for structural optimization design.

[0062] It should be noted that the modeling data of the floor slab in the reverse construction side area is based on the boundary line determined by the reverse construction side area and the forward construction center area confirmed in step S1. The thickness of the floor slab is the thickness of the beamless floor determined in the preliminary structural layout, and the constraint condition of the floor slab should be the positive point of the reverse construction side area, which is similar to the constraint position in the one-dimensional analysis. Since no vertical support is added in the two-dimensional analysis, under the action of the soil side pressure, the stress and strain conditions in the floor slab plane are more clearly displayed. With the one-dimensional analysis method, the correctness of the subsequent three-dimensional and four-dimensional analysis and design results can be conceptually judged.

[0063] In addition, in the two-dimensional analysis and calculation, the soil side pressure is applied to the periphery of the floor plane model established by the software MidaS Gen or SAP 2000 for calculation. After obtaining the unit stress and strain of the analysis, it is judged whether the unit stress is greater than or equal to the design strength of the concrete. If so, the width of the floor in the reverse edge area is increased until the unit stress is less than or equal to the design strength of the concrete. When the unit stress exceeds the design strength of the concrete, there is a risk of damage to the structure. By increasing the width of the floor, the overall stiffness of the structure will be increased, which can effectively reduce the unit stress, thereby avoiding the damage of the structure due to excessive stress.

[0064] S4. Please refer to Figure 4 In this embodiment, a three-dimensional analysis is performed on the basement part of the reverse construction edge area. Specifically, a three-dimensional model of the floor slab of the reverse construction edge area is established, and the component parameters are modified in a preset manner to obtain the overall structural performance information and the corresponding component reinforcement information.

[0065] In 3D analysis, 3D modeling can more accurately simulate the structural form and stress state of the floor slab, so as to comprehensively evaluate its overall performance (including bearing capacity, stiffness, stability, etc.). Based on the analysis results of the 3D model, the arrangement of reinforcement can be optimized to improve the overall stiffness and bearing capacity of the structure. At the same time, the results of the 3D analysis can provide a certain basis and data support for the subsequent 4D analysis.

[0066] It should be noted that when conducting the preliminary structural layout of the three-dimensional model, it includes the preliminary design of the supporting structure, columns, beams, and floor slabs, and a large opening analysis should be carried out in the central area of ​​the work. At the same time, the structural performance of the entire foundation pit must be considered and the design should be carried out from the perspective of the integrity of the structure.

[0067] Specifically, a three-dimensional design calculation is performed. Without considering the effect of actual soil and the entire construction simulation process, the YJK software is used to establish a three-dimensional model of the reverse construction edge area according to the floor width determined by the two-dimensional analysis, adjust the column grid and the corresponding preliminary structural layout, and reasonably modify the component parameters according to the corresponding requirements of the specification. For example, the stress results of each floor of the three-dimensional model are compared with the analysis results of the one-dimensional analysis in step S2 and the analysis results of the two-dimensional analysis in step S3. According to the comparison results, the component parameters are modified. For example, reinforcement measures of component reinforcement can be selectively adopted, among which the number, diameter, and arrangement of reinforcement are all important component parameters.

[0068] S5. Please refer to Figure 5 In this embodiment, a four-dimensional analysis is performed on the basement part of the reverse construction edge area. Specifically, a four-dimensional model is established that takes into account the interaction between soil and the main structure, and a construction simulation analysis of the entire process is performed.

[0069] In the four-dimensional analysis, the effect of actual soil, construction simulation process and the influence of time factors can be fully considered, so as to more accurately evaluate the overall structural performance of the basement part of the reverse construction edge area, where the overall structural performance includes the bearing capacity, stiffness, stability and stress state of the structure at different construction stages and load conditions. For example, by establishing a four-dimensional model that considers the joint effect of soil and main structure and conducting a full-process construction simulation analysis, the most unfavorable working condition and stress condition of the structure can be determined.

[0070] It should be noted that, considering the effect of actual soil and the entire construction simulation process, the preliminary structural information of YJK in the three-dimensional analysis and the actual survey information can be used to build a model through the Midas GTS software, in which the construction situation of the entire reverse construction edge area has been basically simulated according to the actual situation; because the soil factors need to be taken into account at this stage, and the buckling deformation of the floor slab out of the plane can be considered, and the actual situation of the soil in the finite element simulation cannot be fully and truly reflected, the approximate projection stress results obtained by one-dimensional analysis and the in-plane stress distribution obtained by two-dimensional analysis should be compared with those in the four-dimensional analysis.

[0071] Specifically, after establishing a four-dimensional model that considers the interaction between soil and the main structure and conducting a full-process construction simulation analysis, the analysis results obtained by the four-dimensional analysis in step S5 are compared with the analysis results obtained by the one-dimensional analysis in step S2 and the two-dimensional analysis in step S3, respectively, and the analysis results of the one-dimensional analysis are used as a guide to find out the unfavorable stress points and optimize the structural design. By combining the results of the one-dimensional, two-dimensional and four-dimensional analyses, a more comprehensive understanding of the stress state and performance characteristics of the structure can be obtained. Although the one-dimensional analysis is simplified, it can quickly reveal the extreme stress points or weak areas of the structure in a specific direction. Therefore, with the one-dimensional analysis as a guide, these unfavorable stress points can be located and evaluated more quickly, providing direction for subsequent optimization design, wherein the optimization design of the structure includes adjusting the size, shape, material or connection method of the components.

[0072] S6. Compare the analysis results obtained by the four-dimensional analysis in step S5 with the analysis results obtained by the two-dimensional analysis in step S3 and the three-dimensional analysis in step S4, and selectively adjust the reinforcement information of the component based on the comparison results.

[0073] By carrying out one-dimensional analysis, two-dimensional analysis, three-dimensional analysis, and time-space four-dimensional analysis on the basement part of the reverse construction edge area, we can fully and deeply understand the mechanical behavior of this area in different dimensions. Based on the comparison results of these multi-dimensional analyses, the reinforcement design of the basement components can be accurately adjusted to obtain a specific reinforcement scheme that not only meets the actual construction needs but also ensures the safety and stability of the structure. This comprehensive analysis method not only improves the scientificity and accuracy of the design, but also provides strong support for quality control and safety management during the construction process.

[0074] In addition, in order to enable the construction team to correctly and comprehensively understand the structural status and design intent of each stage, a two-set-of-drawings and four-stage drawing expression method can be adopted. Specifically, there are four construction stages in the reverse construction project in the border area, namely the first stage: the reverse construction border area construction stage, the second stage: the normal construction middle area construction stage, the third stage: the partial demolition stage of the reverse construction border area, and the fourth stage: the permanent use stage. Among them, one set of drawings is used to express the first and third stages, and the other set of drawings is used to express the second and fourth stages.

[0075] Example 2

[0076] On the basis of the above-mentioned embodiment, in order to obtain more optimal component reinforcement information, this embodiment further provides specific comparison conditions and adjustment methods of “selectively adjusting component reinforcement information based on comparison results”.

[0077] In one embodiment, it is determined whether the floor stress in the four-dimensional analysis of step S5 is greater than or greater than or equal to the corresponding floor stress in the two-dimensional analysis of step S3. If the floor stress in the four-dimensional analysis is greater than or greater than or equal to the corresponding floor stress in the two-dimensional analysis, and the absolute value of the difference between the two is less than or less than equal to 30% of the floor stress in the two-dimensional analysis, the analysis results obtained by the three-dimensional analysis and the four-dimensional analysis are used for envelope reinforcement design.

[0078] Alternatively, if the floor stress in the four-dimensional analysis is less than or equal to the corresponding floor stress in the two-dimensional analysis, and the absolute value of the difference between the two is less than or equal to 20% of the floor stress in the two-dimensional analysis, the analysis results obtained from the three-dimensional analysis and the four-dimensional analysis are also used for envelope reinforcement design.

[0079] Since the stress conditions in multiple directions and possible load combinations are considered, the floor stress in the four-dimensional analysis may be closer to the actual situation. At the same time, the four-dimensional analysis may also take into account the nonlinear behavior and time effect of the structure, which may lead to an increase in the floor stress. Therefore, the floor stress value in the four-dimensional analysis is generally greater than the floor stress value in the two-dimensional analysis. In this case, no matter the floor stress value in the four-dimensional analysis is greater than the floor stress value in the two-dimensional analysis and the difference is within 30%, or the floor stress value in the four-dimensional analysis is not greater than the floor stress value in the two-dimensional analysis and the difference is within 20%, it shows that the difference between the four-dimensional analysis and the two-dimensional analysis is within an acceptable range. In addition, since the three-dimensional analysis uses YJK software to establish the three-dimensional model of the reverse edge area according to the floor width determined by the two-dimensional analysis, adjust the column grid and the corresponding preliminary structural layout, and compared with the two-dimensional analysis, the three-dimensional analysis can more accurately reflect the stress conditions of the structure in three-dimensional space, such as the interaction and deformation coordination between the components. In this case, the analysis results of the four-dimensional analysis can be used as the basis, and the envelope reinforcement design can be carried out by comparing the results of the three-dimensional analysis and the four-dimensional analysis to ensure the accuracy and reliability of the design.

[0080] It should be noted that the envelope reinforcement design refers to the selection of the most unfavorable stress state for reinforcement design based on the results of various analysis methods during the design process. This method can ensure that the stress of the floor slab in all directions is fully considered and addressed, thereby improving the safety and stability of the structure. Among them, the envelope reinforcement design using the analysis results obtained by three-dimensional analysis and four-dimensional analysis can be different from the results of three-dimensional analysis by considering the confining pressure of the soil. Accordingly, the steel bars of the floor slab parts with larger four-dimensional analysis results can be reasonably strengthened.

[0081] In addition, the difference between the floor stress in the four-dimensional analysis and the corresponding floor stress in the three-dimensional analysis can also be calculated. If the absolute value of the difference between the floor stress in the four-dimensional analysis and the corresponding floor stress in the three-dimensional analysis is less than or equal to 10% of the floor stress in the three-dimensional analysis, the analysis results obtained by the three-dimensional analysis and the four-dimensional analysis are also used for envelope reinforcement design.

[0082] When the difference between the floor stress of the four-dimensional analysis and the three-dimensional analysis is within 10%, it can be considered that the two analysis methods have a high consistency in evaluating the floor stress. This similarity shows that although the two analysis methods may differ in theoretical framework, calculation model or considerations, the stress results they obtain are very close. Therefore, in this case, it is reasonable to use the results of the two analysis methods for envelope reinforcement design, which can ensure the safety of the structure.

[0083] In another embodiment, if the floor stress in the four-dimensional analysis is less than or equal to the corresponding floor stress in the two-dimensional analysis, and the absolute value of the difference between the two is greater than or equal to 20% of the floor stress in the two-dimensional analysis, and the absolute value of the difference between the floor stress in the four-dimensional analysis and the corresponding floor stress in the three-dimensional analysis is greater than or equal to 10% of the floor stress in the four-dimensional analysis, the analysis results obtained by one-dimensional analysis, two-dimensional analysis, three-dimensional analysis and four-dimensional analysis are used for comprehensive envelope reinforcement design.

[0084] When the results of different analysis methods differ greatly, in order to ensure the safety of the structure, it is necessary to use the results of all analysis methods for comprehensive envelope reinforcement. This means that during the design process, all possible stress conditions will be considered and the most unfavorable stress state will be selected for reinforcement to ensure the safety of the structure.

[0085] Furthermore, the analysis results obtained by one-dimensional analysis, two-dimensional analysis, three-dimensional analysis and four-dimensional analysis are used for comprehensive envelope reinforcement. Specifically, the analysis results obtained by three-dimensional analysis are used as the main basis, and the analysis results obtained by one-dimensional analysis, two-dimensional analysis and four-dimensional analysis are used as auxiliary reference. In the uncertain areas, envelope reinforcement design is carried out according to the analysis results obtained by one-dimensional analysis, two-dimensional analysis and four-dimensional analysis.

[0086] It should be noted that in reinforcement design, three-dimensional analysis can more accurately reflect the actual stress state of the structure. By considering the stress of the structure in three directions, a more reasonable reinforcement scheme can be designed to improve the bearing capacity and stability of the structure. In addition, three-dimensional analysis can also help engineers optimize the reinforcement layout. By simulating and analyzing the effects of different reinforcement schemes, the optimal reinforcement layout scheme can be selected to improve the economy and construction efficiency of the structure.

[0087] Three-dimensional analysis has significant advantages in reinforcement design, but one-dimensional analysis, two-dimensional analysis and four-dimensional analysis also play an important auxiliary role. One-dimensional analysis and two-dimensional analysis can provide the stress and deformation conditions of the structure in a specific direction, which helps engineers to have a more comprehensive understanding of the performance of the structure. Four-dimensional analysis can consider time factors or changes in more dimensions, providing richer information for reinforcement design. Therefore, in the process of comprehensive envelope reinforcement design, three-dimensional analysis is used as the main basis, and the analysis results obtained by one-dimensional analysis, two-dimensional analysis and four-dimensional analysis are combined as auxiliary references to ensure the accuracy and rationality of the reinforcement scheme. Furthermore, in the uncertain areas, envelope reinforcement is carried out according to the analysis results obtained by one-dimensional analysis, two-dimensional analysis and four-dimensional analysis, which can further improve the safety and reliability of the reinforcement scheme.

[0088] In the present invention, by sequentially carrying out one-dimensional analysis, two-dimensional analysis, three-dimensional analysis, and time-space four-dimensional analysis on the basement part of the reverse construction edge area, a comprehensive and in-depth understanding of the mechanical behavior of the area in different dimensions can be achieved. Based on the comparison results of these multi-dimensional analyses, the reinforcement design of the basement components can be accurately adjusted to obtain a specific reinforcement scheme that not only meets the actual construction needs but also ensures the safety and stability of the structure. This comprehensive analysis method not only improves the scientificity and accuracy of the design, but also provides strong support for quality control and safety management during the construction process.

[0089] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A structural analysis and design method using an edge area inverse method, characterized in that: The structural analysis and design method comprises: S1. Perform preliminary structural arrangement on the construction area, divide the construction area based on preset conditions, and obtain the initial reverse construction side area and forward construction center area; S2. For the basement part of the top-down construction edge area, simplify the floor unit into a rod unit, convert the soil side pressure in proportion to form a uniformly distributed load acting on the rod unit, and analyze the force condition on the rod unit; S3, establishing a two-dimensional model of the floor slab in the reverse construction edge area, adding the soil side pressure calculated in step S2 to its periphery, and obtaining the unit stress and strain of the analysis; S4, establishing a three-dimensional model of the floor slab in the reverse construction edge area, modifying component parameters in a preset manner, and obtaining overall structural performance information and corresponding component reinforcement information; S5. Establish a four-dimensional model that takes into account the interaction between soil and main structure, and conduct construction simulation analysis of the entire process; S6. Compare the analysis result obtained in step S5 with the analysis results obtained in steps S3 and S4, and selectively adjust the reinforcement information of the component based on the comparison result.

2. The structural analysis and design method using the edge area inverse method according to claim 1 is characterized in that: The preset conditions include a first condition and a second condition; The first condition includes: the basement part of the core tube belongs to the forward construction central area, and the rest belongs to the reverse construction side area; The second condition includes: the width of the floor slab of the reverse-construction side zone is greater than or equal to 10 m, and is at least greater than or equal to 1 / 6 of the side length corresponding to the forward-construction central zone.

3. The structural analysis and design method using the edge area inverse method according to claim 2 is characterized in that: The preset conditions also include: The basement of the high-rise tower of the core tube belongs to the forward construction central area, and if the column position of the high-rise tower is within the range of the second condition, the column position of the high-rise tower belongs to the reverse construction side area; and / or If the podium basement adopts reinforced concrete columns, the podium basement belongs to the forward construction central area; if the podium basement adopts steel tube concrete columns or under the second condition, the podium basement belongs to the reverse construction edge area.

4. The structural analysis and design method using the edge area inverse method according to claim 1 is characterized in that: Step S2 includes: If the side length of the floor unit is less than 1 / 5 of the maximum side length of the longitudinal center area, the floor unit is not taken into consideration when simplifying the floor unit to the bar unit; and / or The length of the rod unit is half of the sum of the side length of the corresponding forward-working center area and the side length of the corresponding reverse-working side area.

5. The structural analysis and design method using the edge area inverse method according to claim 1 is characterized in that: After obtaining the analyzed element stress and strain, step S3 further includes: Determine whether the unit stress is greater than or equal to the design strength of concrete. If so, increase the floor width of the reverse edge area until the unit stress is less than or equal to the design strength of concrete.

6. The structural analysis and design method using the edge area inverse method according to claim 1 is characterized in that: The "modifying component parameters in a preset manner" includes: The stress results of each floor slab of the three-dimensional model are compared with the analysis results of step S2 and step S3, and the component parameters are modified according to the comparison results.

7. The structural analysis and design method using the edge area inverse method according to claim 1 is characterized in that: After establishing a four-dimensional model that takes into account the interaction between soil and the main structure and conducting a full-process construction simulation analysis, the structural analysis and design method also includes: The analysis results obtained in step S5 are compared with the analysis results obtained in steps S2 and S3 respectively, and the analysis results in step S2 are used as a guide to find out the unfavorable stress points and optimize the structural design.

8. The structural analysis and design method using the edge area inverse method according to any one of claims 1 to 7, characterized in that: The "selectively adjusting the reinforcement information of the component based on the comparison result" includes: If the floor stress in step S5 is greater than or equal to the corresponding floor stress in step S3, and the absolute value of the difference between the two is less than or equal to 30% of the floor stress in step S3, the analysis results obtained in steps S4 and S5 are used for envelope reinforcement design; or If the floor stress in step S5 is less than or equal to the corresponding floor stress in step S3, and the absolute value of the difference between the two is less than or equal to 20% of the floor stress in step S3, the analysis results obtained in steps S4 and S5 are used to perform envelope reinforcement design; or If the absolute value of the difference between the floor stress in step S5 and the corresponding floor stress in step S4 is less than or equal to 10% of the floor stress in step S4, the analysis results obtained in steps S4 and S5 are used to perform envelope reinforcement design.

9. The structural analysis and design method using the edge area inverse method according to claim 8 is characterized in that: The "selectively adjusting the reinforcement of the component based on the comparison result" also includes: If the floor stress in step S5 is less than or less than or equal to the corresponding floor stress in step S3, and the absolute value of the difference between the two is greater than or greater than or equal to 20% of the floor stress in step S3, and the absolute value of the difference between the floor stress in step S5 and the corresponding floor stress in step S4 is greater than or greater than 10% of the floor stress in step S4, the analysis results obtained in steps S2, S3, S4 and S5 are used to perform comprehensive envelope reinforcement design.

10. The structural analysis and design method using the edge area inverse method according to claim 9 is characterized in that: The "using the analysis results obtained in step S2, step S3, step S4 and step S5 to perform comprehensive envelope reinforcement design" includes: The analysis result obtained in step S4 is used as the main basis, and the analysis results obtained in steps S2, S3 and S5 are used as auxiliary references. In the uncertain places, the envelope reinforcement design is performed according to the analysis results obtained in steps S2, S3 and S5.

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