Post-impact state detection and evaluation method for concrete box girder protection wall

Abstract

The invention provides a post-impact state detection and evaluation method for a concrete box girder protection wall, and belongs to the technical field of road and bridge detection, and the method comprises the steps: obtaining the comprehensive state data of the protection wall, and enabling the comprehensive state data to comprise the state data of a main region and the state data of a key troubleshooting region; at least one of the main body area state data and the key investigation area state data contains data of different detection types; the damage coefficient of the protection wall is calculated according to the main body area state data and the key investigation area state data; determining a dynamic weighting coefficient, and performing dynamic weighting calculation according to the dynamic weighting coefficient and the damage coefficient to obtain a state evaluation result; wherein the proportions of the dynamic weighting coefficients corresponding to the data of different detection types are different. According to the post-collision state detection and evaluation method for the concrete box girder protection wall, the damage state of the concrete box girder structure after collision can be evaluated and analyzed, and a guarantee is provided for safe operation of the concrete box girder structure.

Description

Technical Field

[0001] The present application relates to the technical field of road and bridge detection, and in particular to a method for detecting and evaluating the post-impact state of a concrete box girder protective wall. Background Art

[0002] The protective wall structure of the railway concrete box girder is set on the left and right sides of the box girder to prevent the train from derailing and play a role in limiting and guiding the vehicle. It prevents the vehicle from falling off the bridge after lateral overturning. It is an important protective structure to ensure vehicle safety. The protective wall structure is set on the high-speed railway bridge structure in many countries at home and abroad. A large number of theoretical studies and actual cases have shown that the protective wall structure has a good limiting and guiding role after the high-speed train derails, and can effectively prevent the train from falling off the bridge after overturning.

[0003] When a high-speed train overturns due to various reasons, it will cause varying degrees of damage to the protective wall structure. Therefore, it is necessary to evaluate the damage to the protective wall structure after the collision to ensure that the protective wall structure is reasonably repaired and strengthened after the impact damage to ensure the safety of train operation.

[0004] In the relevant technology, there is a lack of methods to evaluate the damage state of concrete box girders after being impacted, and it is impossible to provide theoretical and technical support for the repair and reinforcement of the damaged protective wall. Therefore, it is urgent to explore methods for detecting and assessing the state of concrete box girder protective walls after impact, so as to ensure that the structural state of the concrete box girder protective wall structure can be quickly and effectively evaluated after being impacted. Summary of the invention

[0005] The present application provides a method for detecting and evaluating the state of a concrete box girder protective wall after impact, so as to solve the technical problem in the related art that there is a lack of evaluation of the damage state of a concrete box girder after impact.

[0006] The present application provides a method for detecting and evaluating the post-impact state of a concrete box girder protective wall, wherein the protective wall includes a main area and a key inspection area, and the method includes:

[0007] Acquire comprehensive status data of the protective wall, wherein the comprehensive status data includes status data of a main area and status data of a key inspection area, and at least one of the status data of the main area and the status data of the key inspection area contains data of different detection types;

[0008] The damage coefficient of the protective wall is calculated based on the status data of the main area and the status data of the key inspection area;

[0009] Determine the dynamic weighting coefficient, perform dynamic weighting calculation according to the dynamic weighting coefficient and the damage coefficient, and obtain the state assessment result; wherein the dynamic weighting coefficients corresponding to data of different detection types have different proportions.

[0010] In some possible implementations, at least one of the main area data and the key inspection area status data includes the following detection type data:

[0011] Appearance inspection value, crack state test value, steel bar quantity and diameter test value, structural dimension test value and steel bar cover thickness inspection value;

[0012] Among them, the proportions of the dynamic weighting coefficients corresponding to the appearance status inspection value, the crack status test value, the steel bar quantity and diameter test value, the structural dimension test value and the steel bar protection layer thickness inspection value are respectively: 30%, 30%, 10%, 10%, and 20%.

[0013] In some possible implementations, the main area data and the key inspection area status data both include the following detection types of data:

[0014] Appearance inspection value, crack state test value, steel bar quantity and diameter test value, structural dimension test value and steel bar cover thickness inspection value;

[0015] The dynamic weighted calculation is performed according to the dynamic weighted coefficient and the damage coefficient, and is calculated by the following formula:

[0016]

[0017] Among them, Xi is the dynamic weighting coefficient; Ri is the damage coefficient corresponding to data of different detection types.

[0018] In some possible implementations, the damage coefficient corresponding to the appearance status inspection value is calculated by the following formula:

[0019]

[0020] Among them, R1 is the damage coefficient corresponding to the appearance status inspection value, T1 is the damage area of ​​the main area, T2 is the damage area of ​​the key inspection area, M1 is the limit value of the damage area of ​​the main area, and M2 is the total area of ​​the key inspection area.

[0021] In some possible implementations, the damage coefficient corresponding to the crack state test value is calculated by the following formula:

[0022]

[0023] Among them, R2 is the damage coefficient corresponding to the crack state test value, H1 is the maximum longitudinal length of the crack in the key inspection area, H2 is the maximum width of the crack in the key inspection area, K1 is the total longitudinal length of the main area, and K2 is the limit value of the crack width in the main area.

[0024] In some possible implementations, the damage coefficient corresponding to the steel bar protection layer thickness inspection value is calculated by the following formula:

[0025]

[0026] Among them, R1 is the damage coefficient corresponding to the inspection value of the steel bar protective layer thickness, F1 is the test value of the steel bar protective layer thickness in the key inspection area, F2 is the design value of the steel bar protective layer thickness in the key inspection area, and P is the over-thickness limit of the steel bar protective layer thickness in the key inspection area.

[0027] In some possible implementations, the damage coefficient corresponding to the steel bar quantity and diameter test values ​​is calculated by the following formula:

[0028]

[0029] Among them, R4 is the damage coefficient corresponding to the test value of the number and diameter of steel bars, M1 is the number of steel bars in the key inspection area, M2 is the diameter of steel bars in the key inspection area, K1 is the design value of the number of steel bars in the main area, K2 is the design value of the diameter of steel bars in the main area, L1 is the error limit of the number of steel bars in the main area, and L2 is the error limit of the diameter of steel bars in the main area.

[0030] In some possible implementations, the damage coefficient corresponding to the structural dimension test value is calculated by the following formula:

[0031]

[0032] Among them, R5 is the damage coefficient corresponding to the test value of the structural size, Z1 is the longitudinal length of the key inspection area, Z2 is the transverse length of the key inspection area, T1 is the design value of the longitudinal length of the main area, T2 is the design value of the transverse length of the main area, H1 is the error limit of the longitudinal length of the main area, and H2 is the error limit of the transverse length of the main area.

[0033] In some possible implementations, the comprehensive status data is obtained after a load test is performed by a testing device, and the testing device includes:

[0034] Anchoring body, used for fixed connection with the upper end surface of the concrete box girder;

[0035] An actuator, fixedly mounted on the anchoring body, the actuator having an action end for applying a force;

[0036] A distribution beam has one end fixedly connected to the action end and the other end abutting against the side wall of the protective wall. The actuator applies a loading test force to the protective wall through the distribution beam.

[0037] In some possible implementations, the method further includes:

[0038] Determine two check sections, and calculate the structural stiffness of each check section separately;

[0039] Calculate the design stiffness of each check section, divide the structural stiffness of each check section by the corresponding design stiffness, and obtain the safety factors of two check sections;

[0040] The smaller value of the two calculated section safety factors is used as the structural safety factor, and the structural damage state of the protective wall is determined according to the structural safety factor and the state assessment result.

[0041] The post-impact status detection and assessment method for the concrete box girder protective wall provided in the present application divides the comprehensive status data into data of the main area and the key inspection area, so that the method can more comprehensively assess the overall status of the protective wall, and by introducing a dynamic weighting coefficient, weighted calculation is performed according to the importance of data of different detection types, thereby allowing the actual situation to adjust the influence of various types of data and improve the accuracy of the assessment results. In addition, the method provided in the present application quantifies the actual degree of damage to the protective wall by calculating the damage coefficient, thereby providing an accurate scientific basis for subsequent maintenance and reinforcement decisions, and ensuring the structural safety performance and safe operation of the line. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0043] Figure 1 The figure is a schematic cross-sectional view of a concrete box girder involved in the present invention.

[0044] Figure 2 It is a schematic longitudinal cross-sectional view of a concrete box girder protective wall involved in the present invention.

[0045] Figure 3 It is a structural schematic diagram of the concrete box girder post-impact testing device disclosed by the present invention.

[0046] Figure 4 It is a schematic diagram of the analysis and calculation section and the converted section of the concrete box girder protective wall structure disclosed by the present invention.

[0047] Figure 5 It is a schematic diagram of the cross section for analysis and calculation of the concrete box girder protective wall structure disclosed by the present invention.

[0048] Figure 6 The present invention is a schematic diagram of the safety factor calculation process of the concrete box girder protective wall structure disclosed in the present invention.

[0049] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments.

[0050] Description of Reference Numerals

[0051] 100, box beam; 101, flange plate;

[0052] 200. Protective wall; 201. Calculated section I; 202. Calculated section II; 203. Converted section; 300. Anchoring body; 301. Actuator; 302. Distribution beam. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme in the embodiment of the present application will be described in more detail below in conjunction with the drawings in the preferred embodiments of the present application. In the drawings, the same or similar reference numerals throughout represent the same or similar parts or parts with the same or similar functions. The described embodiments are part of the embodiments of the present application, not all of the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limitations on the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application. The embodiments of the present application are described in detail below in conjunction with the drawings.

[0054] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, or it can be an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0055] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present application.

[0056] The terms "first", "second", "third", "fourth", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can, for example, be implemented in an order other than those illustrated or described herein.

[0057] In addition, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus that includes a series of steps or elements is not necessarily limited to those steps or elements explicitly listed, but may include other steps or elements not explicitly listed or inherent to such process, method, product, or apparatus.

[0058] As mentioned in the background technology, concrete box girders are a type of bridge structure commonly used in high-speed railways, highways, and municipal bridges at home and abroad. This type of structure has good rigidity and durability, and is a structure with good technical and economic performance. my country's high-speed railways adopt the form of "bridges instead of roads", using a large number of bridge structures to build high-speed railway lines. Prestressed concrete box girder structures are widely used in bridges to provide good support for high-speed trains.

[0059] The railway concrete box girder protective wall structure is set on the left and right sides of the box girder to limit and guide the vehicle after the train derails, preventing the vehicle from falling off the bridge after lateral overturning. It is an important protective structure to ensure vehicle safety. The high-speed railway bridge structure settings in many countries at home and abroad all adopt protective wall structures. A large number of theoretical studies and actual cases have shown that the protective wall structure has a good limiting and guiding role after the high-speed train derails, and can effectively prevent the train from falling off the bridge after overturning.

[0060] When a high-speed train overturns due to various reasons, it will cause varying degrees of damage to the protective wall structure. Different degrees of damage require targeted maintenance and repairs to varying degrees. Therefore, it is necessary to assess the damage to the protective wall structure after the collision to ensure that the protective wall structure is reasonably repaired and strengthened after the impact damage to ensure the safety of the train operation.

[0061] With the development of my country's high-speed railways, more and more high-speed railway lines and trains are put into use and operation. Under certain special working conditions, trains may derail and overturn, causing damage to the protective wall, resulting in the interruption of the high-speed railway line, which has an important impact on society. However, there is currently no method for evaluating the damage state of concrete box girders after being hit, and there is a lack of testing and analysis methods for the concrete box girder structure protective wall after being hit, which cannot provide support for the repair and strengthening of the damaged protective wall, reducing the rescue efficiency of collision accidents such as train derailment. It is urgent to explore the detection and damage assessment methods for the concrete box girder protective wall after the impact, to ensure that the concrete box girder protective wall structure can quickly and effectively evaluate the structural state after being hit, and to provide protection for the safe operation of high-speed railways.

[0062] To solve the above problems, the present invention proposes a method for detecting the structural state and assessing the damage of a concrete box girder protective wall structure after being impacted. The detection and damage assessment method can assess and analyze the damage state of the concrete box girder structure after the impact, thus providing a guarantee for the safe operation of the concrete box girder structure.

[0063] The following is a description of the structural state detection and damage assessment method of the concrete box girder protective wall structure after being impacted according to an embodiment of the present application in conjunction with the accompanying drawings.

[0064] like Figure 1 As shown, the post-impact state detection and evaluation method of the concrete box girder protective wall provided in the embodiment of the present application, the protective wall 200 includes a main area and a key inspection area, and the method includes:

[0065] Step 100, obtaining comprehensive status data of the protective wall 200, wherein the comprehensive status data includes main area status data and key inspection area status data, and at least one of the main area status data and the key inspection area status data contains data of different detection types;

[0066] Step 200, calculating the damage coefficient of the protective wall 200 according to the main area status data and the key inspection area status data;

[0067] Step 300, determining a dynamic weighting coefficient, performing dynamic weighting calculation according to the dynamic weighting coefficient and the damage coefficient, and obtaining a state assessment result; wherein the dynamic weighting coefficients corresponding to data of different detection types have different proportions.

[0068] From the above description, it can be seen that the post-impact state detection and evaluation method of the concrete box girder protective wall provided in the present application divides the comprehensive state data into data of the main area and the key inspection area, so that the method can more comprehensively evaluate the overall state of the protective wall 200, and by introducing a dynamic weighting coefficient, weighted calculation is performed according to the importance of data of different detection types, thereby allowing the actual situation to adjust the influence of various types of data and improve the accuracy of the evaluation results. In addition, the method provided in the present application quantifies the actual degree of damage to the protective wall 200 by calculating the damage coefficient, thereby providing an accurate scientific basis for subsequent maintenance and reinforcement decisions, thereby ensuring the structural safety performance and safe operation of the line.

[0069] It should be noted that in the embodiment of the present application, the key inspection area refers to the area at the intersection of the protective wall 200 and the concrete box girder 100. This area bears greater stress and is sensitive to damage, and needs to be inspected in a focused manner. The main area refers to other areas except the key inspection area, which will not be described in detail in the following embodiments.

[0070] In addition, in the embodiment of the present application, the concrete box girder 100 can be designed with reference to the structure of the box girder 100 in the road and bridge related technology. The box girder 100 has flange plates 101 on both sides of the top, and a protective wall 200 is respectively provided on the flange plates 101 on both sides.

[0071] In some embodiments, at least one of the main area data and the key inspection area status data includes the following detection type data:

[0072] Appearance inspection value, crack state test value, steel bar quantity and diameter test value, structural dimension test value and steel bar cover thickness inspection value;

[0073] Among them, the proportions of the dynamic weighting coefficients corresponding to the appearance status inspection value, the crack status test value, the steel bar quantity and diameter test value, the structural dimension test value and the steel bar protection layer thickness inspection value are respectively: 30%, 30%, 10%, 10%, and 20%.

[0074] In the above embodiments, the proportions of dynamic weighting coefficients corresponding to data of different detection types are different. For example, as shown in Table 1, Table 1 shows the proportions of dynamic weighting coefficients corresponding to data of different detection types.

[0075] Table 1

[0076] Different types of data Weight <![CDATA[Crack state test value X2]]> 30％ <![CDATA[Appearance status check value X1]]> 30％ <![CDATA[Test value X4 of the quantity and diameter of steel bars]]> 10％ <![CDATA[Structural dimension test value X5]]> 10％ <![CDATA[Reinforcement cover thickness inspection value X3]]> 20％

[0077] By assigning corresponding amplitude weights to data of different detection types, the proportion of different influencing factors in the damaged state can be adjusted more accurately, thereby improving the accuracy of state assessment.

[0078] Furthermore, the main area data and the key inspection area status data both include the following detection types of data:

[0079] Appearance inspection value, crack state test value, steel bar quantity and diameter test value, structural dimension test value and steel bar cover thickness inspection value;

[0080] The dynamic weighted calculation is performed according to the dynamic weighted coefficient and the damage coefficient, and is calculated by the following formula:

[0081]

[0082] Among them, G is the calculated state assessment result, Xi is the dynamic weighting coefficient, and Ri is the damage coefficient corresponding to data of different detection types.

[0083] Exemplarily, the damage coefficient corresponding to the appearance status inspection value is calculated by the following formula:

[0084]

[0085] Among them, R1 is the damage coefficient corresponding to the appearance status inspection value, T1 is the damage area of ​​the main area, T2 is the damage area of ​​the key inspection area, M1 is the limit value of the damage area of ​​the main area, and M2 is the total area of ​​the key inspection area.

[0086] The damaged area of ​​the above-mentioned main area must be less than or equal to the damage area limit value of the main area, and the damaged area of ​​the key inspection area must be less than or equal to the total area of ​​the key inspection area.

[0087] Exemplarily, the damage coefficient corresponding to the crack state test value is calculated by the following formula:

[0088]

[0089] Among them, R2 is the damage coefficient corresponding to the crack state test value, H1 is the maximum longitudinal length of the crack in the key inspection area, H2 is the maximum width of the crack in the key inspection area, K1 is the total longitudinal length of the main area, and K2 is the limit value of the crack width in the main area.

[0090] Exemplarily, the damage coefficient corresponding to the inspection value of the steel bar protective layer thickness is calculated by the following formula:

[0091]

[0092] Among them, R1 is the damage coefficient corresponding to the inspection value of the steel bar protective layer thickness, F1 is the test value of the steel bar protective layer thickness in the key inspection area, F2 is the design value of the steel bar protective layer thickness in the key inspection area, and P is the over-thickness limit of the steel bar protective layer thickness in the key inspection area.

[0093] In the above embodiment, specifically, F1 is the test value of the thickness of the upper transverse steel bar protective layer of the flange plate 101 in the key inspection area, F2 is the design value of the thickness of the upper transverse steel bar protective layer of the flange plate 101 in the key inspection area, and P is the over-thickness limit value of the thickness of the upper transverse steel bar protective layer of the flange plate 101 in the key inspection area.

[0094] Exemplarily, the damage coefficient corresponding to the steel bar quantity and diameter test values ​​is calculated by the following formula:

[0095]

[0096] Among them, R4 is the damage coefficient corresponding to the test value of the number and diameter of steel bars, M1 is the number of steel bars in the key inspection area, M2 is the diameter of steel bars in the key inspection area, K1 is the design value of the number of steel bars in the main area, K2 is the design value of the diameter of steel bars in the main area, L1 is the error limit of the number of steel bars in the main area, and L2 is the error limit of the diameter of steel bars in the main area.

[0097] Exemplarily, the damage coefficient corresponding to the structural dimension test value is calculated by the following formula:

[0098]

[0099] Among them, R5 is the damage coefficient corresponding to the test value of the structural size, Z1 is the longitudinal length of the key inspection area, Z2 is the transverse length of the key inspection area, T1 is the design value of the longitudinal length of the main area, T2 is the design value of the transverse length of the main area, H1 is the error limit of the longitudinal length of the main area, and H2 is the error limit of the transverse length of the main area.

[0100] In the above manner, the final state result is divided into five injury levels: slight, moderate, severe, serious and extremely serious according to the interval range of the theoretical maximum and minimum values ​​of the final calculated state assessment result G and the degree of injury.

[0101] The structural status of the concrete box girder 100 and the protective wall 200 is divided into four levels: A, B, C, and D. Level A is further divided into two levels: AA and A1. Level D is mild, level C is moderate, level B is severe, A1 is severe, and AA is extremely severe. The evaluation and measures involved in each degradation level are as follows:

[0102]

[0103]

[0104] The method for detecting and evaluating the post-impact state of the concrete box girder protective wall proposed in the present invention can directly determine that the structural performance is at level B, C, and D and carry out relevant repairs. However, when it is concluded that the structural performance is at level A, the following on-site tests need to be carried out to verify the state of the structure.

[0105] Specifically, when the structural performance is at Class A, the comprehensive status data is obtained by performing a loading test by a testing device, such as Figure 2 and Figure 3 As shown, the testing device comprises:

[0106] An anchoring body 300 is used to be fixedly connected to the upper end surface of the concrete box beam 100;

[0107] An actuator 301 is fixed on the anchor body 300, and the actuator 301 has an action end for applying a force;

[0108] The distribution beam 302 has one end fixedly connected to the action end and the other end abuts against the side wall of the protective wall 200 . The actuator 301 applies a loading test force to the protective wall 200 through the distribution beam 302 .

[0109] Among them, the structures such as the protective wall 200 and the box beam 100 in the above-mentioned field test are consistent with the steel bar configuration, external dimensions, materials, etc. of the concrete box beam 100 structure, and the performance test of the protective wall 200 structure of the concrete box beam 100 is carried out by field testing. Among them, the anchoring body 300 can be an anchoring steel beam, and the anchoring steel beam and the anchoring bolts are used to fix the actuator 301 on the upper surface of the box beam 100 for loading testing. The protective wall 200 structure is a reinforced concrete structure. Figure 5 The field test form of the single-sided protective wall 200 is given as the preferred form of the present invention. The longitudinal length of the distribution beam 302 is preferably the longitudinal length of the protective wall 200 segment, and the structural performance of the protective wall 200 is generally evaluated.

[0110] Figure 5 The test contents during the post-impact field test of the concrete box beam 100 protective wall 200 of the present invention include load measuring points, displacement measuring points, steel bar strain measuring points, and concrete strain measuring points. The number of measuring points for each model can be adjusted according to actual needs. Among them, load and displacement tests are mandatory test items for the model test of the present invention, and the remaining measuring points are preferred test items. Corresponding measuring points can also be added according to the structural characteristics of the protective wall 200.

[0111] Table 1 shows the loading priority process of the field test of the concrete box beam 100 protective wall 200 structure of the present invention. The load level during the field specimen loading process can be divided into load levels by considering the design load and cracking load under different load combination conditions. The loading process is designed to be 5 cycles, the first cycle is the initial loading cycle, which is used to determine the cracking load of the model specimen; the maximum values ​​of the second, third, fourth, and fifth cycles are the maximum values ​​in the design load combination conditions, which are used to evaluate the stability of the structural state.

[0112] The crack width testing, crack depiction and data testing in Table 1 are the data collection tasks that are completed first during the loading of the model specimen.

[0113]

[0114] In some embodiments, the method further comprises:

[0115] Determine two check sections, and calculate the structural stiffness of each check section separately;

[0116] Calculate the design stiffness of each check section, divide the structural stiffness of each check section by the corresponding design stiffness, and obtain the safety factors of two check sections;

[0117] The smaller value of the two calculated section safety factors is used as the structural safety factor, and the structural damage state of the protective wall 200 is determined according to the structural safety factor and the state assessment result.

[0118] Specifically, Figure 4 and Figure 5 As shown, the check section is selected according to the principle of bearing the largest load, the smallest cross-sectional size, significant cross-sectional changes and stress concentration. For example, two check sections, check section I 201 and check section II 202, are selected. Check section I 201 is selected because it is located in the stress concentration area and is prone to cracks, so it is selected as the check section; check section II 202 is selected because the load effect at this position is the largest, and it is the connection between the flange plate 101 and the box beam 100, and the location where the structural stiffness changes significantly.

[0119] like Figure 6 As shown, the specific calculation method includes:

[0120] ① Determine the check section according to the concrete section size and reinforcement configuration of the check section.

[0121] ② Calculate the structural stiffness E according to the longitudinal unit sections of the two check sections respectively;

[0122] Specifically, according to the ratio of elastic modulus of steel and concrete, the steel bar is converted into concrete cross section.

[0123]

[0124] Where n is the ratio of the elastic modulus of steel bars to the elastic modulus of concrete; Ec is the elastic modulus of concrete; Es is the elastic modulus of steel bars.

[0125] The calculated stiffness of each check section is calculated according to the structural characteristics of the converted section and is obtained by the following formula:

[0126]

[0127] Among them, E1 is the calculated stiffness of the check section Ⅰ201; b1 is the width of the section 203 after the check section Ⅰ201 is converted; h1 is the height of the section 203 after the check section Ⅰ201 is converted; E2 is the calculated stiffness of the check section Ⅱ202; b2 is the width of the section 203 after the check section Ⅱ202 is converted; h2 is the height of the section 203 after the check section Ⅱ202 is converted.

[0128] ③ Divide the structural stiffness obtained from the field test by the calculated stiffness to obtain the safety factor corresponding to the two check sections;

[0129]

[0130] Where n is the safety factor; Ei is the structural stiffness of the i-check section; and Edi is the calculated stiffness of the i-check section.

[0131] After calculating the safety factor of each check section in the above manner, the smallest section safety factor is obtained by comparison and used as the total safety factor of the structure.

[0132] According to the obtained total safety factor and referring to the structural performance evaluation level given in Table 2, the structural damage state of the protective wall 200 after being impacted is obtained.

[0133] Table 2 shows the structural damage status evaluation table of the concrete box girder 100 and the protective wall 200 of the present invention.

[0134]

[0135] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0136] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A method for detecting and evaluating the state of a concrete box girder protective wall after impact, characterized in that: The protective wall (200) comprises a main area and a key inspection area, and the method comprises: Obtaining comprehensive status data of the protective wall (200), the comprehensive status data comprising main area status data and key inspection area status data, at least one of the main area status data and the key inspection area status data containing data of different detection types; Calculating the damage coefficient of the protective wall (200) according to the status data of the main area and the status data of the key inspection area; Determine the dynamic weighting coefficient, perform dynamic weighting calculation according to the dynamic weighting coefficient and the damage coefficient, and obtain the state assessment result; wherein the dynamic weighting coefficients corresponding to data of different detection types have different proportions.

2. The method for detecting and evaluating the post-impact state of a concrete box girder protective wall according to claim 1 is characterized in that: At least one of the main area data and the key inspection area status data includes the following detection types of data: Appearance inspection value, crack state test value, steel bar quantity and diameter test value, structural dimension test value and steel bar cover thickness inspection value; Among them, the proportions of the dynamic weighting coefficients corresponding to the appearance status inspection value, the crack status test value, the steel bar quantity and diameter test value, the structural dimension test value and the steel bar protection layer thickness inspection value are respectively: 30%, 30%, 10%, 10%, and 20%.

3. The method for detecting and evaluating the post-impact state of a concrete box girder protective wall according to claim 2 is characterized in that: The main area data and the key inspection area status data both include the following detection types of data: Appearance inspection value, crack state test value, steel bar quantity and diameter test value, structural dimension test value and steel bar cover thickness inspection value; The dynamic weighted calculation is performed according to the dynamic weighted coefficient and the damage coefficient, and is calculated by the following formula: Among them, Xi is the dynamic weighting coefficient; Ri is the damage coefficient corresponding to data of different detection types.

4. The method for detecting and evaluating the post-impact state of a concrete box girder protective wall according to claim 3 is characterized in that: The damage coefficient corresponding to the appearance status inspection value is calculated by the following formula: Among them, R1 is the damage coefficient corresponding to the appearance status inspection value, T1 is the damage area of ​​the main area, T2 is the damage area of ​​the key inspection area, M1 is the limit value of the damage area of ​​the main area, and M2 is the total area of ​​the key inspection area.

5. The method for detecting and evaluating the post-impact state of a concrete box girder protective wall according to claim 3 is characterized in that: The damage coefficient corresponding to the crack state test value is calculated by the following formula: Among them, R2 is the damage coefficient corresponding to the crack state test value, H1 is the maximum longitudinal length of the crack in the key inspection area, H2 is the maximum width of the crack in the key inspection area, K1 is the total longitudinal length of the main area, and K2 is the limit value of the crack width in the main area.

6. The method for detecting and evaluating the post-impact state of a concrete box girder protective wall according to claim 3 is characterized in that: The damage coefficient corresponding to the steel bar protection layer thickness inspection value is calculated by the following formula: Among them, R1 is the damage coefficient corresponding to the inspection value of the steel bar protective layer thickness, F1 is the test value of the steel bar protective layer thickness in the key inspection area, F2 is the design value of the steel bar protective layer thickness in the key inspection area, and P is the over-thickness limit of the steel bar protective layer thickness in the key inspection area.

7. The method for detecting and evaluating the post-impact state of a concrete box girder protective wall according to claim 3 is characterized in that: The damage coefficient corresponding to the steel bar quantity and diameter test values ​​is calculated by the following formula: Among them, R4 is the damage coefficient corresponding to the test value of the number and diameter of steel bars, M1 is the number of steel bars in the key inspection area, M2 is the diameter of steel bars in the key inspection area, K1 is the design value of the number of steel bars in the main area, K2 is the design value of the diameter of steel bars in the main area, L1 is the error limit of the number of steel bars in the main area, and L2 is the error limit of the diameter of steel bars in the main area.

8. The method for detecting and evaluating the post-impact state of a concrete box girder protective wall according to claim 3 is characterized in that: The damage coefficient corresponding to the test value of the structural size is calculated by the following formula: Among them, R5 is the damage coefficient corresponding to the test value of the structural size, Z1 is the longitudinal length of the key inspection area, Z2 is the transverse length of the key inspection area, T1 is the design value of the longitudinal length of the main area, T2 is the design value of the transverse length of the main area, H1 is the error limit of the longitudinal length of the main area, and H2 is the error limit of the transverse length of the main area.

9. The method for detecting and evaluating the post-impact state of a concrete box girder protective wall according to any one of claims 1 to 8, characterized in that: The comprehensive status data is obtained after a load test is performed by a testing device, and the testing device comprises: An anchoring body (300) is used for fixedly connecting with the upper end surface of the concrete box beam; An actuator (301) is fixedly mounted on the anchoring body (300), and the actuator (301) has an action end for applying a force; A distribution beam (302) has one end fixedly connected to the action end and the other end abutting against the side wall of the protective wall (200). The actuator (301) applies a loading test force to the protective wall (200) through the distribution beam (302).

10. The method for detecting and evaluating the post-impact state of a concrete box girder protective wall according to any one of claims 1 to 8, characterized in that: The method further comprises: Determine two check sections, and calculate the structural stiffness of each check section separately; Calculate the design stiffness of each check section, divide the structural stiffness of each check section by the corresponding design stiffness, and obtain the safety factors of two check sections; The smaller value of the two calculated section safety factors is used as the structural safety factor, and the structural damage state of the protective wall (200) is determined according to the structural safety factor and the state assessment result.

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