242 results about "Flexural rigidity" patented technology

The invention discloses a steel plate floor support plate and an implementation method, and aims at solving the problems that a traditional floor support plate is insufficient in rigidity and strength, large in steel consumption, complex in construction, low in material utilization rate and the like. The floor support plate comprises a wide upper flange (the minimum width is larger than or equal to 30 mm), a wave-shaped reinforcing steel bar web member, a lower chord reinforcing steel bar and a profiling thin-bottom steel plate, the wide upper flange is of a combined type or thin steel plate type or trapezoidal steel pipe structure, and a side plate forming an inclination angle with a vertical shaft enhances the out-of-plane stability; the inclination angles of the steel bar web members are consistent with those of longitudinal ribs (trapezoidal ribs, closed inverted triangular ribs and the like) of the upper flange side plates and the profiled thin-bottom steel plates, so that line-surface contact welding is realized; the profiled thin-bottom steel plate is provided with longitudinal ribs and transverse ribs, so that the overall rigidity is improved; the lower chord steel bar adopts a double-layer design to strengthen node stress. According to the implementation method, industrial production is achieved through cold roll forming, automatic resistance welding and other processes. A traditional triangular truss is optimized into a trapezoid and four-side box type space structure, the bending rigidity is remarkably improved (the inertia distance between the upper flange and the profiling thin bottom steel plate is increased by 40% or above), the steel consumption is reduced by about 30%, the connection reliability is enhanced, meanwhile, the concrete consumption is reduced, the construction process is simplified, and the structure is suitable for various building scenes such as large span and heavy load.

The invention discloses a polyester fiber acoustical board with high yield strength. The polyester fiber acoustical board comprises a micro-perforated metal surface layer, a gradient density polyester fiber layer, a honeycomb metal framework layer and an elastic damping bottom layer which are sequentially stacked and fixed through mucilage glue from top to bottom. A vertically-distributed metal surrounding plate is arranged around the side edge of the micro-perforated metal surface layer, the metal surrounding plate and the micro-perforated metal surface layer are of an integrally-formed structure, and the gradient density polyester fiber layer and the honeycomb metal framework layer are wrapped by the metal surrounding plate. And the honeycomb metal framework layer is fixed with the adjacent upper and lower layers through mucilage glue, and is also fixed with the metal coaming through rivets. By means of the innovative composite lamination design, the strength defect of a traditional polyester fiber acoustic board is effectively overcome. The micro-perforated metal surface layer and the integrally formed metal coaming form a rigid outer frame, so that the internal fiber layer is protected from mechanical damage, and the overall flexural rigidity is remarkably improved through the bearing effect of the metal framework.

The invention relates to the technical field of constructional engineering equipment, in particular to a rigidity and energy dissipation adjustable composite energy dissipation bearing device which comprises a first connecting plate, a second connecting plate, a first damping part and a second damping part. The first damping piece is arranged on the first connecting plate on the column body in a friction sliding mode, and the second damping piece is connected between the beam body and the first damping piece in an included angle mode, so that the flexural rigidity of the beam-column joint can be effectively improved under the action of frequent earthquakes, and the initial rigidity and lateral displacement resistance of the structure are enhanced; the rigid response performance of the structure under the action of small earthquakes is improved; the second damping piece can adjust the energy dissipation path through the change of the included angle between the length direction of the second damping piece and the axis of the column body in the earthquake action process, the friction sliding mechanism of the first damping piece is matched, the energy dissipation capacity of the joint under the earthquake action is effectively improved, and therefore structural stress concentration is reduced, and structural damage is delayed. The structure is light in weight, convenient to install and wide in application range.

The invention discloses a method for rapidly evaluating the flexural rigidity of a bridge under vehicle-induced excitation, and belongs to the technical field of flexural rigidity evaluation of variable cross-section beams. The method comprises the following steps of: firstly, acquiring a bridge time-history response by adopting vehicle movement loading, separating a power component by utilizing a VMD method, then identifying a main frequency of an IMF component through FFT, removing the power component higher than a bridge fundamental frequency, and reconstructing a bridge actual measurement quasi-static time-history response; then, an axle effect in bridge actual measurement quasi-static time history response is eliminated, an influence line recognition model is established, and Tikhonov regularization is introduced to further solve a deflection influence line; then deriving an analytic solution of a deflection influence line of the variable cross-section continuous beam based on a virtual work principle, establishing a mathematical relationship between the flexural rigidity and the deflection influence line, and identifying the flexural rigidity of the bridge through the deflection influence line based on the mathematical relationship to obtain flexural rigidity distribution of the full bridge; finally, multiple evaluation indexes are defined and calculated, the bending rigidity distribution of the full bridge is comprehensively evaluated, and the method has the advantages of being good in engineering applicability and high in safety evaluation innovativeness.

The invention belongs to the field of deep foundation pit intelligent supporting systems, and particularly relates to a deep foundation pit intelligent supporting system based on oblique beam grid and digital twinning and a collaborative construction method.The deep foundation pit intelligent supporting system based on oblique beam grid and digital twinning comprises an oblique beam grid supporting structure composed of two-way crossed steel oblique beams, and the outer layer of each steel oblique beam is a Q355B steel pipe with the thickness not smaller than 12 mm; the inclined beam is filled with ultra-high performance concrete with the compressive strength not smaller than 150 MPa, the inclination angle of the inclined beam ranges from 25 degrees to 60 degrees, and an MEMS micro-electro-mechanical system sensor is pre-buried at a node; and the digital twin platform integrates the geological BIM model and the LSTM neural network prediction model. The bending rigidity is improved through the oblique beam grid supporting structure and the concrete filled steel tube composite beam, the inclination angle ranges from 25 degrees to 60 degrees, force flow transmission is optimized, and micro-strain-level stress monitoring is achieved through the MEMS sensors embedded in the nodes. A digital twin platform and an LSTM model are fused with 12-dimensional parameters, the 72-hour deformation prediction error is smaller than or equal to 1.5 mm, and compared with a traditional experience algorithm, the precision is improved.

The invention discloses a frame structure design method based on rigidity reduction. The method comprises the following steps that 1, rod end bending moments Mb and Mc and axial force Nc of frame beams and columns are obtained through calculation; step 2, obtaining actual reinforcement areas Asb0 and Asc0, section sizes and concrete strength of frame beams and columns; 3, the equivalent stiffness Kb1 of the frame beam is obtained through calculation according to the formula Kb1 = Mb0.75y / phi b0.75y; 4, the equivalent stiffness Kc1 of the frame column is obtained through calculation according to the formula Kc1 = Mc0.75y / phi c0.75y; 5, comparing the equivalent stiffness of the frame beam and the frame column with the initial flexural stiffness, and ending after the deviation is less than or equal to 15%; 6, calculating a shear force design value of the frame beam, calculating stirrups needing to be configured for the frame beam, and rechecking a shear-resistant section; and 7, calculating a shear force design value of the frame column, calculating stirrups needing to be configured for the frame column, and rechecking a shear-resistant section. Compared with the prior art, an overall calculation model of the frame structure is established, the real rigidity of a structural member is obtained through multiple iterations, section reinforcement is optimized, and the reinforcement amount is reduced; and the overall anti-seismic performance is improved.

The invention provides a method and a system for analyzing influence of local loading and unloading on deformation of an existing shield tunnel, and relates to the field of influence of foundation pit construction on the existing tunnel. The method comprises the steps that shield tunnel vertical additional stress caused by foundation pit excavation is calculated through a Mindlin stress solution; analyzing the influence of the longitudinal axial force on the flexural rigidity and shear rigidity of the circular seam joint, and dividing a joint deformation mode into three stages according to the relative magnitude of the axial force and the bending moment and the vertical displacement between rings; a tunnel displacement control equation is established based on a Winkler foundation model, loop iteration is conducted through a state space method, and the rigidity of a circular seam joint is dynamically adjusted to be matched with the final deformation mode of the circular seam joint; and finally, constructing a prediction system, and outputting a deformation value of the shield tunnel by inputting the number of iterations and parameters of a foundation pit, bolts, concrete and segments. By means of the method, deformation prediction of the existing shield tunnel can be achieved for foundation pit construction, an effective scientific basis is provided for foundation pit engineering construction, the problem that parameter decision of operators on a construction site is difficult is solved, and foundation pit engineering site construction is truly guided.

A stabilizer clamp (20) for fastening a stabilizer rod (40) to a vehicle is disclosed. The stabilizer clamp (20) has a receptacle (22) for the stabilizer rod (40), wherein the receptacle (22) is formed as an intermediate space between two legs (24, 24a, 24b) for fastening the stabilizer clamp (20) to the vehicle and a bend (26) connecting the two legs (24, 24a, 24b). The stabilizer clamp (20) is made predominantly of plastic or predominantly of fiber-reinforced plastic. The arch (26) has, in an axially arranged sectional plane relative to the center of gravity of the sectional plane, a flexural rigidity with respect to a curvature about the axial axis of at least 35,000,000 Nmm2, wherein the sectional plane passes through a circle center (28) of the arch or a fictitious radial center of a stabilizer rod for whose diameter the stabilizer clamp (20) is designed.

The invention discloses a stay cable analysis digital twinborn model construction method, which comprises the following steps of: constructing a stay cable space three-dimensional vibration motion partial differential equation based on a material linear elasticity hypothesis and a double-coordinate system theory, and setting boundary conditions and initial conditions of the stay cable space three-dimensional vibration motion partial differential equation; a Galerkin multi-mode truncation method is adopted to obtain a displacement function of superposition of an end displacement excitation item and a vibration mode item; deducing a three-way strong coupling ordinary differential equation set through symbolic operation, and solving by using a step-variable Runge-Kutta algorithm to obtain a stay cable analysis digital twin model with stable parameters; structural response data are obtained through the sensor network and calculated, and when the obtained cable force, flexural rigidity and damping ratio exceed threshold values, a model updating mechanism is triggered for updating; and then the updated stay cable analysis digital twin model is obtained. According to the method, the real dynamic characteristics of the stay cable can be restored with high precision, and effective support is provided for structural state evaluation and early warning.

The utility model belongs to the technical field of steel structures, and particularly relates to I-shaped steel for a bridge, which comprises an I-shaped steel body, a plurality of holes are uniformly distributed on a web of the I-shaped steel body, and foamed aluminum is filled in each hole. A plurality of reinforcing ribs are further arranged on a web of the I-shaped steel body, the reinforcing ribs and the holes are distributed in a staggered mode, every two adjacent I-shaped steel bodies are connected through a connecting mechanism, the holes are of a hexagonal structure and evenly divided into a plurality of groups, and the multiple groups of holes are evenly distributed in the length direction of the I-shaped steel body. The plurality of groups of holes and the plurality of reinforcing ribs are alternately distributed; according to the utility model, the plurality of holes are formed in the I-shaped steel body, and the foamed aluminum is filled in each hole to form a'metal framework + core material 'composite structure, so that compared with a solid web, the weight is reduced by 25%-30%, and the flexural rigidity is improved at the same time; the adjacent I-shaped steel is connected through the connecting mechanism, and detachable connection is achieved.

The sandwich panel of the present invention comprises: a foamed molded body; a first thermoplastic continuous fiber reinforced woven body fused to an upper portion of the foamed molded body; a second thermoplastic continuous fiber reinforced woven body fused to a lower portion of the foamed molded body; and one or more composite material bars embedded in the foamed molded body. The sandwich panel exhibits excellent rigidity (flexural strength, flexural rigidity, and maximum deflection), lightweight properties, and the like.

This invention discloses a method, system, equipment, and storage medium for calculating the deformation of a pipe-jacking structure considering the soil resistance between the pipe and culvert. The method includes the following steps: S1. Simplifying the pipe-jacking structure as an elastic thin plate, and further simplifying the problem to the deformation of an elastic thin plate with fixed opposite sides and simply supported opposite sides under a uniformly distributed load on a Winkler elastic foundation, obtaining the differential equation of the bending surface of the thin plate on the Winkler elastic foundation and the expression for the boundary conditions of the thin plate; S2. Determining the elastic modulus when the pipe-jacking structure is simplified to an elastic thin plate, and calculating the bending stiffness D of the pipe-jacking structure; S3. Solving the differential equation of the bending surface of the thin plate on the Winkler elastic foundation using a hybrid solution method combining trigonometric series and the force method, obtaining the deflection formula of the elastic thin plate placed on the elastic foundation under a uniformly distributed load. This invention can accurately predict the deformation of pipe-jacking structures.

The present invention discloses a calculation method for the equivalent flexural stiffness of a shield tunnel reinforced by synchronous grouting, including: 1) establishing a finite element calculation model of the shield tunnel considering the effect of synchronous grouting; 2) conducting stress-strain analysis at the segment joints of the shield tunnel and establishing a stress-strain equilibrium differential equation; 3) deriving the theoretical solution of the equivalent flexural stiffness of the shield tunnel under the action of synchronous grouting based on the principle of similar triangles and the definition of the equivalent flexural stiffness of the shield tunnel; 4) quantifying the synchronous grouting sensitive parameters and the equivalent flexural stiffness as a relationship matrix through calibration β , α , Z , and analyzing the influence of the thickness of the synchronous grouting layer, the elastic modulus of the grout, and the curing time on the equivalent flexural stiffness of the shield tunnel. The method of the present invention can quickly calculate the equivalent flexural stiffness of the shield tunnel reinforced by synchronous grouting while ensuring the accuracy of the calculation results, and can be widely applied to the reinforcement projects of shield tunnels, providing guidance for the design of shield tunnels reinforced by synchronous grouting.

The invention discloses a shield tunnel segment joint U-shaped active reinforcing structure and a construction method, the structure comprises a longitudinal preformed groove, an annular load-bearing steel bar, a connecting plate, a door-shaped clamping seat, a U-shaped reinforcing member and filling mortar, the U-shaped reinforcing member comprises a horizontal tensile plate, a fixing plate and a positioning plate, and the door-shaped clamping seat comprises a bottom plate, a side plate and a supporting end. The invention provides an active reinforcement measure for the segment joint, which is used for actively reinforcing the segment joint in a high-risk area of shield tunnel construction and preventing sudden damage accidents of the shield tunnel caused by damage of the segment joint, and the segment joint reinforcement structure not only can be mounted on the inner cambered surface of a shield tunnel segment lining, but also can be mounted on the inner cambered surface of the shield tunnel segment lining; the reinforcing structure can be installed on the outer arc face of a shield tunnel segmental lining and can also be installed on the outer arc face of the shield tunnel segmental lining, the reinforcing structure is connected with the segmental annular load-bearing steel bars in a welded mode through the connecting plates, and the ultimate bearing capacity and the bending rigidity of a segmental connector can be greatly improved.

The invention discloses a large-diameter slide-resistant pile double-layer reinforcement cage and a construction method thereof. The reinforcement cage comprises a concrete outer layer, outer longitudinal bars, middle-layer reinforcing stirrups, inner longitudinal bars, inner reinforcing stirrups, triangular supports, first corner joints and second corner joints. An inner cavity is formed in the concrete outer layer, outer longitudinal bars are evenly arranged in the inner cavity in the circumferential direction, and spiral outer stirrups are arranged on the outer walls of the outer longitudinal bars. Structural design is adopted, a closed-loop three-dimensional truss supporting system is constructed through the spiral outer stirrups, the middle-layer reinforcing stirrups, the inner reinforcing stirrups and the triangular supports, the outer longitudinal bars and the inner longitudinal bars are integrated into a high-strength overall framework, and the bending rigidity and the deformation resistance of a cage body are remarkably improved; the stress of the 41-ton cage body in the whole process of transportation, hoisting and concrete pouring can be effectively dispersed, structural damage to the long-size cage body is avoided, and the structural form of the device is compatible with the construction sequence that the outer cage is hoisted downwards first and then the inner cage is hoisted upwards, and the inner cage is connected upwards and then the outer cage is constructed.

The present invention discloses an annular cylindrical workpiece, a polishing platen, a polishing device, and a method for controlling a polishing surface profile. The method comprises: an expansion chamber disposed between a support plate and a polishing plate; one end of the expansion chamber is connected to a pressure control source; the pressure control source varies an output load based on the axial length of an outer wall of the expansion chamber, the bending stiffness of the outer wall, the wall thickness of the outer wall, the elastic modulus of the outer wall, and the Poisson's ratio, thereby varying the deflection of the outer wall; the outer wall of the expansion chamber is configured to transmit a torque to the polishing plate when the deflection increases, thereby deforming the polishing surface profile of the polishing plate. The present invention achieves the technical effect of reducing the difficulty of controlling the polishing surface profile while improving the accuracy of controlling the polishing surface profile.

The present invention discloses a truss-combined steel-concrete cylindrical wind power foundation, which includes a steel-concrete cylinder skirt; above the steel-concrete cylinder skirt, a reinforced concrete beam system structure is cast and provided; at the top center position of the reinforced concrete beam system structure, a vertically distributed steel-concrete vertical transition section is fixedly connected; the top of the steel-concrete vertical transition section is connected to the bottom of the steel vertical transition section; the steel-concrete vertical transition section and the steel vertical transition section are hollow cylindrical structures with a truss structure built therein; the top of the steel-concrete vertical transition section is open; both the upper and lower ends of the steel vertical transition section are open; the central points of the steel-concrete cylinder skirt, the steel-concrete vertical transition section, the steel vertical transition section and the truss are located on the same central axis. The truss-combined steel-concrete cylindrical wind power foundation disclosed by the present invention can meet the installation requirements of large-megawatt wind turbines in deep water areas, and has relatively high flexural stiffness and good anti-overturning ability.

The application provides a short cable force and stiffness meta-heuristic intelligent identification method considering bending stiffness, and belongs to the field of bridge structure health monitoring and parameter identification. First, based on the measured vibration frequency of the cable structure, the initial value range of the cable force and the bending stiffness is determined by using a simplified analytical model; then a parameter space is constructed within the range, and candidate parameter combinations are generated by random sampling or distribution sampling; the corresponding theoretical frequency is calculated based on the W-W algorithm; the data items of the loss function between the measured frequency and the theoretical frequency are constructed, and the physical loss items of the loss function are constructed by using the vibration differential equation; the parameter inversion is carried out by combining global search and local optimization, and the adaptive interval contraction strategy is introduced to improve the calculation efficiency and the identification accuracy; finally, the optimal cable force and bending stiffness parameters are obtained. The method does not need to rely on the initial accurate parameters, has high robustness and engineering applicability, and can significantly improve the identification accuracy of the cable force and the stiffness.

The invention discloses an inner flange single-pipe tower local anti-bending and anti-shearing rigidity reinforcing device and method.The reinforcing device comprises an upper circular channel steel, a lower circular channel steel, structural ribs, an inner flange reinforcing rib connecting structure and a fixed prestress spring structure; the upper circular channel steel and the lower circular channel steel are connected through structural ribs; fixed prestressed spring structures are arranged in grooves of the upper circular channel steel and the lower circular channel steel; inner flange reinforcing rib connecting structures are arranged at the bottom of the upper circular channel steel and the top of the lower circular channel steel; the upper circular steel channel and the lower circular steel channel are each formed by splicing two C-shaped steel channels, and the two C-shaped steel channels are fixed through circumferential gap filling rubber. By means of the design, on the basis that the external structure of the inner flange single-pipe tower is not changed, the bending rigidity of the local dangerous section is improved, the shearing force of the dangerous section is reduced, and then the technical effect of enhancing the strength of the flange plates of the two-section single-pipe tower is achieved.

This invention discloses an XIE beam, comprising a box girder body, which is formed by an upper panel (1), a left web (2), a lower panel (3), and a right web (4). Inside the box girder body are scissor bracing plates (6) and horizontal steel plates (5). The two ends of the horizontal steel plates (5) are connected to the longitudinal midpoints of the left web (2) and the right web (4), respectively. The midpoint of the scissor bracing plates (6) is located at the transverse midpoint of the horizontal steel plates (5). The upper ends of the scissor bracing plates (6) are connected to the longitudinal 1 / 4 points of the left web (2) and the right web (4), respectively, and the lower ends of the scissor bracing plates (6) are connected to the longitudinal 3 / 4 points of the left web (2) and the right web (4), respectively. Compared to traditional box-section beams of the same area, the XIE beam significantly increases the bending stiffness EI without causing web instability.

The utility model relates to a bridge large cantilever flange plate reinforcing and supporting structure which comprises a bridge body and a cantilever arranged on one side of the bridge body. A light-weight supporting mechanism used for supporting the cantilever is arranged between the bottom of the cantilever and one side of the bridge body, the L-shaped supporting frame and the inclined supporting inclined rod form a triangular stable system, when the cantilever bears a vertical load, the load is transmitted to the bridge body through the supporting frame, the supporting inclined rod provides horizontal resistance, the bending moment of the root of the cantilever is remarkably reduced, and the stability of the cantilever is improved. Due to the high strength of the aluminum alloy material and the filling of the foam core material, it is ensured that the structure has enough flexural rigidity on the premise of light weight, local buckling is avoided, the supporting inclined rods are inserted into the corresponding mounting grooves of the supporting frame for positioning through the upper mounting base and the lower mounting base, final fixing is completed through the limiting pieces, and when the mounting bolts are screwed into the limiting sleeves, the supporting inclined rods are fixed. The sleeve presses the mounting base to be tightly attached to the mounting groove to form rigid connection, welding is not needed through the design, the pre-tightening force of the bolt is adjustable, and different load requirements are met.

Plug connection unit (1), comprising at least one first electrical contact element (10) designed as a projection (11) and at least one second electrical contact element (20) designed as a receptacle (21) for the projection (11), which are designed to realize an electrically conductive connection and a mechanical fastening of the projection (11) in the receptacle (21) at least along a first translational degree of freedom (40) of the projection along its insertion direction (41) into the receptacle (21) when the projection (11) is arranged in the receptacle (21), and wherein at least one of the two contact elements (10, 20) comprises a compensation device (50) for enabling relative movements (70) of sections of this contact element (10, 20) along the first translational degree of freedom (40),which has a lower tensile stiffness than the connection stiffness of the realized mechanical fastening of the projection (11) in the receptacle (21), wherein the compensation device (50) has at least one section of reduced flexural stiffness (51) which imparts the reduced tensile stiffness to the compensation device (50), and the section of reduced flexural stiffness (51) comprises a meandering bending element (52), characterized in that a pressure element (54) is arranged on at least one of two side edges (53) of the meandering bending element (52) opposite one another along the first translational degree of freedom (40), for bearing against the respective opposite side edge (53) in the event of a pressure load on the bending element (52) in the direction of the respective other contact element (10, 20), wherein the second electrical contact element (20),the at least one section of reduced flexural rigidity (51) and the pressure element (54) lie in one plane.,

The invention discloses a similar design method for an underwater vibration table test model of a reinforced concrete rectangular pier. The method comprises the steps of determining geometric similarity constants; determining an elastic modulus similarity constant, a longitudinal bar strength similarity constant, a stirrup strength similarity constant and a water density similarity constant of the reduced-scale pier; determining an acceleration similarity constant of the reduced-scale pier; determining a structural density similarity constant; determining a flexural rigidity similarity constant of the rectangular section of the reinforced concrete pier; determining the wall thickness of the reduced-scale pier with the hollow structure; determining the weight of the bridge pier in unit height and converting the weight into a mass block of an iron block or a lead block with the same weight; determining a longitudinal bar area similarity constant and a stirrup area similarity constant of the reduced-scale pier; and correcting the stirrup area similarity constant and the like. The method provided by the invention can provide a feasible method for similar design of the reinforced concrete rectangular pier model in an underwater vibration table test.

A purpose of the present invention is to provide a polyethylene terephthalate film for foldable displays and the like that have a sufficient elastic modulus in tension required of films for foldable displays and that has excellent flexural rigidity. Portable terminals or image display devices including, mounted therein, the polyethylene terephthalate film for foldable displays provide beautiful images, are highly functional, and have excellent convenience including portability and the like.　The polyethylene terephthalate film for foldable displays has an MD flexural rigidity Fa and a TD flexural rigidity Fb in terms of flexural rigidity for 15-μm thickness, the sum of Fa and Fb being 0.05 gf·cm2 / cm or greater, and has a longitudinal-direction elongation at break of 10% or higher and a width-direction elongation at break of 10% or higher. The poly ethylene terephthalate film can be folded along both a first bending direction and a second bending direction, which is orthogonal to the first bending direction.

This receptacle (1) comprises at least one gas-permeable element (2, 4) defining a part of a chamber (3) for an active substance (6). Each gas-permeable element (2, 4) has a base wall (20, 40) and a side wall (22, 42), the base wall (20, 40) comprising perforations (26, 46). The receptacle (1) further comprises a breathable member (5, 7) secured at its periphery in a receiving portion (25, 47) of the at least one gas-permeable element (2, 4) so as to cover the perforations. The breathable member (5, 7) is selected so that a ratio of a bending resistance of the breathable member (5, 7) to a length of insertion (l25, l47) of the breathable member in the receiving portion (25, 47) is between 10 N.m-1 and 100 N.m-1. In addition, an outer diameter of the breathable member (5, 7) is strictly higher than an inner diameter of the receiving portion (25, 47) so that, upon insertion of the breathable member (5, 7) into the receiving portion (25, 47), friction is established between a peripheral edge of the breathable member (5, 7) and an internal surface of the receiving portion (25, 47).

The invention relates to the technical field of switch rails, in particular to a production method of an elastic bendable switch rail for a compound dividing turnout, which comprises the following steps: determining the steel rail model of the switch rail according to the model of a stock rail; determining the machining range of the switch rail according to the steel rail model; precise cutting is conducted on the determined machining range through slicing machining, the horizontal inertia moment and the flexural rigidity of the switch rail are weakened, and an elastic bendable section is formed; the cut switch rail is subjected to precision verification; forging and pressing the point rail subjected to precision verification, and processing the section of the point rail into a common steel rail section consistent with that of the stock rail; the forged and pressed switch rail is cooled, straightened and detected, the switch rail produced through the method is stable and simple in structure, the problems that bolts are broken off, rail seams are eroded and the like are reduced, the reliability of the switch rail is improved, the service life of the switch rail is prolonged, and maintenance convenience of the switch rail is improved.

The utility model belongs to the technical field of medical instruments, and discloses a puncture guide wire which comprises a puncture body and a rigidity balancing sleeve. The puncture body comprises at least two first puncture sections which are connected in sequence, and in every two adjacent first puncture sections, the diameter of the first puncture section close to the far end of the puncture guide wire is smaller than that of the other first puncture section; the number of the rigidity balance sleeves is at least two, the rigidity balance sleeves correspond to the first puncture sections in a one-to-one mode, the corresponding first puncture sections are fixedly sleeved with the rigidity balance sleeves, and in every two adjacent rigidity balance sleeves, the outer diameter of the rigidity balance sleeve close to the far end of the puncture guide wire is larger than that of the other rigidity balance sleeve. The flexural rigidity of the rigidity balance sleeve close to the far end of the puncture guide wire is larger than that of the other rigidity balance sleeve. Puncture guide wires with different strengths do not need to be replaced repeatedly, so that the operation time is saved, and the operation risk is reduced. And the size of the included angle opening of the U-shaped puncture head cannot be increased along with the feeding of the puncture guide wire, so that the blood vessel is prevented from being burst.

The present application belongs to the technical field of industrial detection, and particularly relates to a forging round steel straightness online detection method based on point cloud data, which comprises the following steps: firstly, obtaining original point cloud and multi-dimensional physical characteristic data of the round steel in a transmission state; then, slicing the point cloud, and combining local geometric missing features and thermal deformation driving features to calculate a compensation step, and correcting a primary centroid to obtain a real three-dimensional physical axis; subsequently, projecting the axis to an orthogonal plane, and using a restriction relationship between local curvature and material bending stiffness to obtain a pseudo-boundary penalty factor, and then correcting an envelope angle and calculating a comprehensive straightness error. The present application eliminates the interference of point cloud missing, thermal eccentricity and surface microscopic defects, and improves the accuracy of the forging round steel straightness detection.

The application provides a new type of structure of a main tower in a multi-tower suspension bridge and a construction method thereof, which comprises a main tower, a plurality of oblique suspension cables, a first stiffening beam and a plurality of main cable saddles; the plurality of main cable saddles are vertically fixed on the top of the main tower in parallel and at intervals along the transverse direction of the main tower; the plurality of oblique suspension cables are respectively arranged on the two sides of the main tower in an inclined manner, the upper end of each oblique suspension cable is anchored in the lower bearing plate of the top of the main tower, and the lower end is connected to the corresponding first stiffening beam; and the first stiffening beam is arranged on the two sides of the main tower. The structure and the method utilize the components of the structure to improve the longitudinal bending stiffness of the main tower, do not affect the overall appearance of the whole bridge, are convenient for construction and do not increase the process.

The utility model discloses a truss floor support plate with high rigidity and heat preservation and sound insulation functions, and is characterized by further comprising a concrete rib poured on the top of the truss and inside the top of the truss and a heat preservation and insulation plate connected to the bottom of the concrete bottom plate. The utility model sets the concrete rib, pours it on the top of the truss, and forms a longitudinal connection support by wrapping the truss inside, thereby significantly improving the bending stiffness and load capacity of the floor support plate. During construction, the utility model can also reduce the establishment of support columns of the floor support plate, reduce construction operation time, and reduce construction cost. The setting of the heat preservation and insulation layer effectively prevents heat transfer, reduces building energy consumption, and meets building energy-saving standards. At the same time, the heat preservation and insulation plate and the overall structure of the floor support plate jointly act on sound propagation to achieve good blocking effect, create a quiet and comfortable environment inside the building, and are suitable for various places with high noise control requirements.