51 results about "Neutral axis" patented technology

The invention relates to the technical field of construction and the technical field of software, and discloses a fabricated structure evaluation method and device based on a toughness value and carbon emission, and the method comprises the steps: adding the damage volumes of all interfaces, and obtaining the damage amount of a fabricated structure; when the damage amount of the fabricated structure is within the damage range, a repair scheme of the fabricated structure is obtained, and the carbon emission amount of the repair scheme is generated; according to the length of each interface, the inertia moment of the complete part of each interface, the moving distance of the neutral axis of each interface and the contact surface rigidity model, the contact surface rigidity of the fabricated structure is generated, and according to the contact surface rigidity of the fabricated structure, the material elasticity modulus of the fabricated structure and the toughness model, the toughness value of the fabricated structure is generated. And performing specific value calculation on the carbon emission of the repair scheme and the toughness value of the fabricated structure to generate an evaluation value of the repair scheme. According to the invention, the evaluation efficiency of the repair scheme of the fabricated structure can be improved.

The invention discloses a compression test clamping tool, system and method for a variable-thickness beveled laminated plate composite material, and relates to the technical field of aviation composite material mechanical property testing. The first long chuck and the second long chuck are respectively mounted on a variable-thickness side and an equal-thickness side of the beveled laminated plate sample, and the first long chuck mounted on the variable-thickness side is gradually thickened on a conical beveled layer and a thin section of the beveled laminated plate sample. According to the invention, the additional bending moment caused by eccentricity of a neutral shaft is effectively inhibited through the gradually-changed thickening design of the variable-thickness side long chuck in cooperation with gap control, and active inhibition of buckling instability of a beveling area is realized in combination with rigid fixation and surface roughening treatment of the short chuck; the method has the advantages that buckling instability is restrained, a failure area is accurately positioned, and samples of different configurations are adapted.

The invention discloses a composite beam capable of enhancing the ultimate strength of an ultimate concrete structure. The span of the beam is measured, a bending moment graph of the beam is drawn, according to analysis of the bending moment graph, UHPC is selected for a pure bending section (the middle of the span) above a neutral axis of the beam, the upper half part of the beam is covered, and common concrete is used for the rest parts; half of the beam height is selected to use UHPC on the upper portion, and the structural ultimate strength of the composite beam can be improved; the FRP rib is used on the lower portion of the beam, the tensile property and ductility of the lower portion can be improved, a sleeve grouting anchorage device (the inner wall of a metal sleeve is provided with threads) and a wedge-shaped anchorage device (the clamping section is wrapped with a copper sleeve) are adopted, the anchoring reliability is ensured through the double effects of chemical bonding and mechanical meshing, and due to the fact that the FRP rib can be subjected to brittle failure and is preset to be in a super rib failure mode, the tensile strength and ductility of the lower portion can be improved. The problem of brittle failure of the FRP rib is solved. The beam is simple in design, convenient to construct, reasonable in stress, high in structural ultimate strength, high in reliability, wide in application range and material-saving.

The invention provides an improved CHM-based RC beam fatigue life prediction method and system, and relates to the technical field of RC beam fatigue life prediction, and the method comprises the specific steps: constructing a crack hinge model, splitting an RC beam into a midspan virtual crack hinge and elastic bodies at two sides, collecting section parameters and beam body basic parameters, and carrying out the construction of a crack hinge model; calculating the axial force of the stress component and the bending moment of each axial force to the neutral axis; setting a cycle block division rule, calculating strain and axial force increments, recording cycle times under the current cycle block, and obtaining a balance error value; using a genetic algorithm to optimize section parameters to obtain an optimal combination; and calculating an accumulated damage value, comparing the accumulated damage value with a threshold to judge failure, and if failure, accumulating cycle times to obtain the life. According to the method, the damage difference of different stress amplitudes under the same deflection is accurately distinguished, a reliable basis of a mechanical level is provided for life prediction, an evolution chain from crack propagation to stress redistribution to damage acceleration is truly restored, and the model is highly matched with the true damage process of the RC beam.

The application discloses a pipeline connecting piece deflection experiment device, which comprises an experiment table and further comprises a movable mounting frame arranged above the experiment table and used for driving a distance measuring sensor to move and avoid the loading path of a lifting test head; the lifting test head is arranged above the movable mounting frame and used for testing and pushing the connecting piece and simultaneously driving the movable mounting frame to move; and the adjustable placing frame is arranged below the lifting test head and used for placing the connecting piece and simultaneously adjusting the placing height of the connecting piece. Through the cooperation of the adjustable placing frame, the distance measuring sensor and the control device, the distance measuring sensor can detect the initial distance on the upper surface of the connecting piece in real time, the control device can drive the second hydraulic rod according to the thickness judged according to the distance, the placing block can be lifted along the opening outer sleeve, and the neutral axis of the connecting piece and the loading axis of the test head can be accurately matched, so that the stress deviation problem caused by the fact that the traditional fixed support cannot be adapted to connecting pieces with different thicknesses is solved.

The invention belongs to the technical field of bridge steel structure design, and discloses a method and system for determining the arrangement positions of multiple longitudinal stiffening ribs of a steel bridge web, and the method comprises the steps that constraint of a steel top plate, a steel bottom plate and two transverse stiffening ribs on a mother plate is simply supported; dividing the stiffening plate into four-side simply supported sub-grids according to the longitudinal stiffening ribs, calculating bending and shearing buckling coefficients and obtaining critical buckling stress; a bending and buckling coefficient is expressed as a function of a clear distance between longitudinal stiffening ribs based on geometric similarity; and adopting a bending and shearing interaction buckling criterion, recursively solving the position of each longitudinal stiffening rib from a pressed edge, and carrying out constraint screening according to monotonically increasing distance, arrangement not crossing a neutral axis and the like. According to the method, reasonable arrangement can be directly output, and design consistency and efficiency are improved.

To specify a damage form and a damage place of a member level of a steel structure building, and to accurately monitor damage.SOLUTION: A strain detector is directly provided on a surface of a column and a beam of a multi-story steel structure building having a steel column and a steel beam, (1) First information on yield and local buckling of the column and (2) second information on buckling, cracking, breaking, and a neutral axis position in combination with a slab of the beam are obtained, a degree of damage of the steel column and beam is evaluated based on the first information and the second information, and determination on restoration is made based on the evaluation.SELECTED DRAWING: Figure 1

This invention discloses a method for strength calculation of a detachable support device. The method includes: obtaining the supporting force and radial force per unit length of the detachable support device; calculating the bending moment and horizontal tensile force at the connecting section based on the supporting force and the radial force per unit length; establishing the static moment equilibrium equation of the connecting section and determining the neutral axis position of the connecting section through iterative calculation; calculating the moment of inertia of the connecting section based on the neutral axis position; and calculating the maximum tensile stress borne by the fastener based on the moment of inertia, the bending moment, and the horizontal tensile force, so as to perform strength verification of the connecting section. This invention derives the strength verification formula and judgment criteria for key stress sections in detachable support structures, which is convenient for engineering technicians and ensures operational safety.

To provide a calculation device and the like capable of calculating data usable for designing of a composite slab decreased in cost.SOLUTION: A calculation device 1 includes: a storage unit 12 which stores a position Ae of a first neutral axis NA1 of a cross section SF1 in a first direction X of a composite slab 100; a first calculation unit 13 which calculates a position Ac of a second neutral axis NA2 of a cross section SF2 in a second direction Y of the composite slab 100; and a second calculation unit 14 which calculates a proportion of a second force Pe applied to a component in the first direction X of the composite slab 100 among a first force Pm, to the first force Pm pressing the composite slab 100 in a thickness direction Z on the basis of the position Ae of the first neutral axis NA1 and the position Ac of the second neutral axis NA2.SELECTED DRAWING: Figure 2

The invention provides a method for analyzing the optimal installation position and the vibration reduction effect of a gear damping ring, and the method comprises the steps: S1, carrying out the modal analysis of an initially designed unslotted spiral bevel gear shaft, and determining a dangerous vibration mode and the corresponding modal displacement; s2, damping ring design is carried out aiming at a dangerous vibration mode which cannot be avoided by frequency modulation, a position with large modal displacement is selected for slotting, and gear shaft strength checking is carried out; s3, a damping ring is installed in the slotted gear shaft, and modal analysis is conducted on the bevel gear shaft assembly; s4, the maximum radial displacement, the axial displacement and the neutral axis radius of the dangerous vibration mode at the damping groove position are obtained through analysis; s5, according to the damping ring vibration attenuation principle, drawing a curve graph of the resonance amplitude coefficient Q and the initial displacement, and evaluating the vibration attenuation effect; and S6, checking the strength of the damping ring. According to the invention, timeliness and economical efficiency of gear shaft damping ring design are taken into consideration, and structure adjustment is completed before a test, so that engineering cost is saved.

The application provides a packaging structure based on secondary Bessel function simple branch modulation, an anti-vibration fiber laser and a packaging method, and belongs to the technical field of fiber laser packaging. The packaging structure comprises a metal base, the metal base is provided with a groove, the groove is provided with a fiber grating area near the neutral axis of the bottom of the groove, the bottom of the groove is provided with a convex structure, the shape of the convex structure is an asymmetric arc shape, and the curve of the arc shape is generated by a secondary Bessel curve. The groove is provided with a fiber, and the two ends of the fiber are fixed on the bottom of the groove. The fiber remains in a relaxed state in the middle segment area of the groove. A gap is left around the middle segment of the groove, or low modulus material is filled in the gap. The application effectively improves the lateral equivalent stiffness, multi-step improves the structure natural frequency in multiple directions, and further improves the overall first-order natural frequency, so that excellent frequency noise suppression capability is shown in the vibration test, and the stability of the fiber laser under acceleration disturbance is greatly improved.

This invention provides a method and system for determining the longitudinal equivalent bending stiffness and deformation of a double-circular shield tunnel. The double-circular shield tunnel is an underground prefabricated composite slender cylindrical structure assembled from precast segments connected by high-strength bolts during the tunneling process of a tunnel boring machine. Its cross-section is formed by the joining of two large circular arcs. Based on the design parameters of the double-circular shield tunnel cross-section, the corresponding bolt average linear stiffness, neutral axis position, and neutral axis position angle can be determined. Then, based on the position of the neutral axis, the longitudinal equivalent bending stiffness of the double-circular shield tunnel can be calculated using the corresponding formula. The beneficial effects of this invention are: it improves the reliability and accuracy of the longitudinal equivalent bending stiffness of the double-circular shield tunnel, provides assistance for the longitudinal structural design of double-circular shield tunnels, is of great significance for assessing the impact of adjacent construction on the double-circular shield tunnel, and further obtains deformation and stress indicators, providing a reference for the deformation and stress safety monitoring of double-circular shield tunnels.

The invention relates to a method for calculating the flexural capacity of a hogging moment area of a reinforced concrete composite beam based on a UHPC thin layer. The method comprises the steps that a test piece is prepared, measuring points are arranged, a load strain curve and a loading result graph of the test piece are obtained through a pressure loading test, and flexural performance characterization is determined. Determining an associated stress area of the composite beam according to the bending resistance characterization, presetting a first assumption condition, and performing derivation based on a strain expression, an internal force expression and a force balance equation to obtain a calculation expression of a cracking bending moment; presetting a second assumption condition, deducing and determining the position of a plastic neutral shaft, establishing a moment balance equation, and deducing according to the section strain expression, the internal force expression and the moment balance equation to obtain a calculation expression of the flexural capacity of the composite beam.

The invention relates to the technical field of support-free calculation, in particular to a 4D steel fiber concrete thin laminated slab support-free calculation method, which comprises the following steps of: acquiring structural parameters and material parameters of a laminated slab, calculating a neutral axis position and converting a cross-sectional inertia moment; based on the characteristic value of the steel fiber content and the influence coefficient of the steel fiber content on the axis tensile strength, the concrete axis tensile strength is corrected, and the cracking bending moment is calculated; respectively calculating the contribution of a truss web member to the equivalent flexural rigidity according to a truss binding mode; combining the influence coefficient of the steel fiber on the short-term rigidity of the flexural member and the contribution value to obtain the short-term rigidity before cracking; and the cracking bending moment and the short-term rigidity are compared with the corresponding threshold values respectively, and if the requirements are met, it is judged that support-free construction of the laminated slab can be achieved. According to the method, whether the laminated slab can be constructed without support or not is accurately judged.

A force sensor comprising a beam having a longitudinal center axis and a neutral axis that extends along a beam surface parallel to the center axis. A first half-bridge includes tension resistors. A second half-bridge includes tension resistors. A third half-bridge includes compression resistors. A fourth half-bridge includes compression resistors. The half-bridges are arranged on the beam surface such that redundant measurements of orthogonal components of a force imparted to the beam can be made using four different combinations of three of the half-bridges. The redundant measurements can be used to identify a malfunction of one or more of the resistors.

The present application relates to a tunnel lining external load inversion method and system based on a physical information neural network, obtaining monitoring data of the inner surface of the tunnel lining to be inverted; according to curved beam theory, establishing a control equation of external load and lining neutral axis deformation, and determining boundary conditions; according to the theory of material mechanics, establishing the corresponding relationship between the strain and displacement of the inner surface of the lining and the strain and displacement of the neutral axis position; constructing a physical information neural network, taking the spatial coordinates of the lining as the input of the physical information neural network, and taking the normal displacement, tangential displacement of the neutral axis at different coordinates and the external load of the lining as the output, and converting the neutral axis displacement into the strain and displacement of the inner surface of the lining; through training of the physical information neural network, the input-output relationship satisfies the control equation of the external load and the lining deformation, the boundary conditions and the monitoring data, and the normal displacement, tangential displacement of the neutral axis at the corresponding coordinates and the external load of the lining are obtained, which are the inversion results.

The application provides a continuum robot macro-micro motion device and method based on eccentric mechanism, which comprises a plurality of unit bodies connected in sequence, any unit body comprising a rigid section and a bendable section; the rigid section of the unit body is provided with a positioning block, the middle part of the positioning block is formed with a central cavity, and the positioning block is further provided with an eccentric macro drive cavity and an eccentric micro drive cavity; a drive rope is arranged in the macro drive cavity, and a bendable fiber with an eccentric cavity is arranged in the micro drive cavity. The motion ability of the robot is enhanced by rotating the bendable fiber with the eccentric cavity, two hot-drawing polymer fibers with eccentric inner cavities are inserted into the micro drive cavity of the continuum robot, the macro motion of the robot is completed by stretching the drive rope, the micro motion is provided by the rotation of the eccentrically arranged fiber, and the basic principle of the micro motion is to rely on the slight change of the neutral axis of the continuum robot.

Force / torque sensor (10), comprising: a tool adapter plate (WAP), wherein the WAP (12) is configured to be connected to a first object: a mounting adapter plate (MAP) wherein the MAP (14) is configured to be connected to a second object; one or more deformable supports (16) which connect the WAP (12) to the MAP (14); a first pair of deformation measuring elements (1-6) attached only to one side of each support, wherein the deformation measuring elements (1-6) are spaced apart on opposite sides from a neutral axis (18) of the support (16) and are configured to convert tensile and compressive forces on the surface of one side of the support (16), which are caused by a deformation of the support (16), into electrical signals; and a measuring circuit which is designed to measure, in response to electrical signals from all deformation measuring elements (1-6), the direction and magnitude of the force and torque between the first and second objects; and a relief cut (34), parallel to the upper surface, at a distance from the upper surface which is not greater than the depth of the blind recess, through the ring-shaped body (14) and the supports (16), but not through the central area (12), wherein the relief cut defines a base to which the central area (12), but not the ring-shaped element (14) and the supports (16) are connected, and leaving the ring-shaped element (14) connected to the central area (12) only by the support (16).

The present invention discloses a simplified calculation method and system for the shear force and opening of segment joints in immersed tube tunnels. The method comprises: determining basic assumptions; then setting the relative axial and vertical deformations and relative rotation angles at the neutral axis of the joint, and clarifying the calculation method for the deformation of the concrete end spring, Ω waterstop, and shear key; then performing force analysis on the concrete per unit area of ​​the end face, the shear key, etc., deriving force formulas, and clarifying the expressions and force mechanisms for the axial force, shear force, and bending moment; considering the extreme conditions of overall heating and cooling, deriving the heating using an elastic foundation beam model and treating the cooling as an articulated joint, and simulating using three-dimensional finite element software; finally, determining the influencing factors and assumptions based on longitudinal three-dimensional model parameter analysis, establishing and deriving a simplified theoretical calculation model, and verifying the formula by comparing the results of the three-dimensional calculation model. This method achieves efficient and accurate calculation of the shear force and opening of segment joints.

The application discloses a method for calculating ultimate flexural bearing capacity of FRP reinforced concrete pile, and belongs to the technical field of concrete pile bearing capacity analysis. The method comprises the following steps: obtaining the geometric parameters of the pile section and constructing a layered discrete grid model; tracking the actual compressive stress transmission path of the concrete compression zone, and decomposing the actual compressive stress transmission path into a plurality of nonlinear compressive stress transmission sub-paths; calculating the local stiffness attenuation coefficient of each sub-path, and superimposing to generate the global stiffness degradation distribution atlas of the concrete compression zone; determining the actual stress peak point position of the compression zone based on the atlas, updating the initial position of the neutral axis, and iteratively solving the balanced position of the neutral axis; and calculating the ultimate flexural bearing capacity of the FRP reinforced concrete pile according to the balanced position of the neutral axis. The method can more accurately reflect the bending failure mechanism of the pile body by simulating the nonlinear compressive stress transmission and stiffness degradation distribution of the concrete in the compression zone and dynamically determining the neutral axis according to the actual stress peak.

This invention discloses a plug-type longitudinally tensioned CFRP plate anchorage system and its construction method, belonging to the field of external prestressing reinforcement technology in civil engineering. It includes a structural member to be reinforced and a CFRP plate. Both ends of the CFRP plate are connected to the structural member through anchoring devices. At least one of the anchoring devices is a plug-type longitudinally tensioned anchorage device. At least one support device is also provided between the CFRP plate and the structural member to be reinforced. The CFRP plate is located away from the neutral axis of the structural member to enhance the prestressing effect, thereby specifically solving the technical problem of mid-span deflection of the structural member to be reinforced. In the plug-type longitudinally tensioned anchorage device, prestress loss can be avoided by inserting pins into the strip holes and pin holes, and by filling the redundant space of the strip holes with plugs, making construction more convenient. At the same time, the tensioning frame, sliding seat, and pre-tensioning frame can be easily disassembled after inserting the pins and filling the plugs, reducing construction costs.

The present application relates to a kind of prestressed steel wood combination node stress performance analysis method and device, method includes the following steps: S1, the key parameter of prestressed steel wood combination node is obtained;S2, based on the direct balance method of beam-column interface and key parameter, wood beam stress balance equation is established, wood beam stress balance equation is solved, the control function of beam end neutral axis height is obtained, control function is the function about beam-column interface opening angle;S3, the parameter of control function of beam end neutral axis height is changed, and the different critical angle in the opening angle change process of beam-column interface is obtained by calculation;S4, based on the control function of beam end neutral axis height, critical angle and node bending moment, bending moment-angle curve is obtained.Compared with prior art, the present application has the advantages of accurate and fast analysis.

The invention discloses an anti-eccentric loading tool device for an axial loading test of a stiffened plate. The device belongs to the technical field of ship and ocean engineering structure tests and is composed of a stiffened plate test piece, a steel head assembly, an end loading clamp, a side clamp and a supporting base. The steel head is welded to the end of the stiffened plate according to the neutralizing shaft, the loading clamp is adopted for clamping, it is ensured that loading force acts along the neutralizing shaft of the stiffened plate, and end face bending moment is avoided; meanwhile, adjustable clamps are arranged on the two sides of the stiffened plate, flexible adjustment and clamping are conducted according to the position of the test piece, accurate simulation of the four-side simple support boundary conditions is achieved, and the loading precision and the test reliability are improved; according to the invention, high-precision loading path control and real boundary condition reproduction are realized through a fixed loading end, centering steel head welding, an adjustable side clamp and a rigid base; the device can prevent loading eccentricity, eliminate end face bending moment and improve loading precision and repeatability; and meanwhile, the device is suitable for buckling and ultimate bearing capacity tests of different types of stiffened plates.

The application belongs to the technical field of vortex-induced vibration test, and discloses a three-dimensional vortex-induced vibration test device and method for submarine cable. The device generates reciprocating bending vibration and reciprocating torsion around the axis of the submarine cable to be tested in a single vertical plane, and equivalently combines the three-dimensional vortex-induced vibration trajectory coupled with the cross-flow direction and the flow direction by using a simple mechanical structure. The device has the advantages of simple structure, low cost and suitability for conventional fatigue test of large-scale submarine cable models. Meanwhile, the axial sliding degree of freedom and the rotation degree of freedom around the axis of the submarine cable to be tested are released in a rolling contact mode, so that the rotation degree of freedom is avoided from being stuck while the intermediate node constraint is realized. The method makes the bending neutral axis of the cross section of the submarine cable to be tested rotate periodically under the coupling effect of bending and torsion, so as to equivalently combine the three-dimensional vortex-induced vibration fatigue load on the submarine cable to be tested, and realize the equivalent simulation of the bending and torsion coupling fatigue effect of the submarine cable.

This application relates to the fields of construction technology and software technology. It discloses a method and apparatus for evaluating prefabricated structures based on toughness value and carbon emissions. The method includes: summing the failure volumes of each interface to obtain the failure amount of the prefabricated structure; when the failure amount of the prefabricated structure is within the failure range, obtaining a repair plan for the prefabricated structure and generating the carbon emissions of the repair plan; generating the contact surface stiffness of the prefabricated structure based on the length of each interface, the moment of inertia of the complete portion of each interface, the displacement distance of the neutral axis of each interface, and the contact surface stiffness model; generating the toughness value of the prefabricated structure based on the contact surface stiffness, the material elastic modulus of the prefabricated structure, and the toughness model; and calculating the ratio between the carbon emissions of the repair plan and the toughness value of the prefabricated structure to generate an evaluation value for the repair plan. This application can improve the evaluation efficiency of repair plans for prefabricated structures.

The application provides a kind of fatigue life prediction method and system based on improved CHM RC beam, it is related to RC beam fatigue life prediction technical field, specific steps include: crack hinge model is built, RC beam is split into virtual crack hinge in midspan and two sides elastomer, section parameter and beam body basic parameter are collected, the bending moment of stress component axial force and each axial force to neutral axis is calculated;Set cycle block division rule, calculate strain and axial force increment, record the cycle number under current cycle block and obtain the balance error value;Optimize section parameter with genetic algorithm to get optimal combination;Calculate cumulative damage value, compare with threshold value to determine failure, if failure, add cycle number to get life.The application accurately distinguishes the damage difference of different stress amplitudes under the same deflection, provides reliable basis at mechanics level for life prediction, truly restores the evolution chain of crack propagation to stress redistribution and then to damage acceleration, makes the model highly match with the real damage process of RC beam.

The invention discloses a concrete box girder nonlinear damage identification method considering a shear hysteresis effect, and the method comprises the steps: estimating the position of a neutral axis of a box girder through long gauge length strain and material performance, and then determining the curvature distribution, bending rigidity and deflection. A simulation result shows that the evaluation parameter (bending rigidity) can clearly and quantitatively reflect the degradation process of the box girder. Meanwhile, the long gauge length strain can reflect global response and can also capture local changes, and the structural response obtained through inversion is highly consistent with the actual measurement result. Compared with a finite element model correction method, the method does not need a finite element model, and can consider nonlinear and shear hysteresis effects; meanwhile, the method is suitable for the whole process of structure failure.

The invention discloses a wind power blade buckling test vector bending moment calculation method and device based on a neutral axis, and relates to the field of wind power blade component testing. The method comprises the following steps: completing coordinate conversion from a full-size blade to a blade section according to a neutral axis, an elastic axis and an elastic axis coordinate system of the full-size blade; calculating the strain value of the blade section through the structural characteristics of the blade section and the coordinate conversion bending moment variable; calculating to obtain a neutral axis and an inclination angle according to the strain value of the blade section, and generating a trailing edge section section; calculating the position of a load shaft of the trailing edge section, further calculating the strain and vector force of a specific position, and finally obtaining the vector bending moment of the trailing edge section. The device comprises a steel structure tool, a vector bending moment loading device and an electrical control system. The loading device controls the loading direction of a loading oil cylinder through four small electric cylinders, and application of the vector bending moment is achieved. According to the method, the full-size test is mapped through the part-level test of the trailing edge section, and the vector bending moment borne by the trailing edge section is analyzed, so that the load matching degree of the blade test and the real stress working condition is improved.

The application provides a method for calculating the characteristic value of the bending bearing capacity of a combined structure beam of steel and UHPC, different constitutive models are adopted according to the performance characteristics of UHPC, T-shaped steel beams and steel bars in the combined structure beam, the contribution of the strain hardening performance of the materials to the bending bearing capacity is fully considered, and the real performance of the structure can be obtained compared with the ideal elastic-plastic model; meanwhile, the initial values of the cross-section curvature, the iterative calculation increment of the curvature and the iterative calculation increment of the position of the neutral axis for the conventional bridge calculation are given, the influence coefficient method is adopted to search the position of the neutral axis and the cross-section curvature, which is helpful to accelerate the searching speed and solve the problem of non-convergence caused by the artificial setting of the iterative increment; finally, the strain of the top of the UHPC concrete reaching the compressive ultimate strain of the UHPC or the strain of the bottom of the T-shaped steel beam reaching the ultimate strain of the steel is simultaneously taken as the judgment condition, and both the crushing of the UHPC and the reaching of the tensile ultimate strength of the steel can be considered.

The present invention discloses a method for calculating the bending moment of reinforced concrete components taking into account the change in the position of the neutral axis, including the steps of: 1. judging whether the cross section of the reinforced concrete component is cracked; 2. executing step 3 when the cross section is not cracked; 3. executing step 6 when cracking occurs; 4. calculating the curvature; 5. obtaining the position of the central axis; 6. calculating the effective depth of the crack; 7. calculating the effective moment of inertia and the curvature; 8. assuming the position of the central axis of the reinforced concrete component with a cracked cross section so that the cross section is subjected to force balance and calculating the true moment of inertia; 9. obtaining the true position of the central axis of the reinforced concrete component with a cracked cross section; 10. calculating the bending moment. The method of the present invention has simple steps, reasonable design, and convenient implementation. It can be effectively applied to the calculation of the bending moment of reinforced concrete components. The calculation result is more accurate, takes into account the change in the position of the neutral axis, reflects the true situation of the bending stiffness of the cracked cross section, has a significant effect, and is easy to promote.