45results about How to "Practical engineering application value is great" patented technology

The invention relates to a determination method based on an ANSYS second development platform of the initial completion initial cable force of a cable-stayed bridge. The method uses the design cable force as the target value, considers the geometric non-linear effect and performs iteration for solving and correcting the cable initial strain under the action of dead load. The method comprises the following specific steps: any group of cable forces is assumed to be added on the stay cable in the mode of initial strain, dead load is added to calculate, the *do-loop command language is used to extract the calculated cable force of the stay cable and check whether the error between the cable force and the target completion cable force is within an available limit; if the error is large, the indifference method is used to correct the stay cable initial strain, then the error is calculated again until the error is within the available limit; and the initial completion initial cable force canbe obtained by multiplying the last calculated group of stay cable initial strains by the elastic modulus of the stay cable which is corrected by considering the vertical effect. By using the method,the solving time of the completion initial cable force of the cable-stayed bridge can be reduced and the precision can be increased, thus the method has large practical engineering application value.

The invention discloses an extended black-start scheme bi-level programming optimization method capable of improving the safety of a recovery process, provides a new idea for the recovery control of an initial stage after blackout, enables the safety factors affecting the recovery process to be introduced to an optimization target so as to improve the safety of an extended black-start scheme in anactual recovery process, gives consideration to the main-slave logic relation between unit recovery and path recovery, and achieves the building of an extended black-start scheme bi-level programmingoptimization model. The upper level optimization takes the maximum comprehensive efficiency of the scheme under the safety condition as the target, and a decision making variable is a started unit. The lower level optimization takes the solving of a recovery path, which contains a key path, is high in recovery safety and gives consideration to the recovery of an important load, as the target, anda decision making variable is a to-be-recovered path. A hybrid algorithm which combines an improved bacterial foraging algorithm with a shortest path method based on a Dijkstra algorithm is employedfor solving the model. The recovery process is higher in safety, the recovery effect is improved, and the method has the practical engineering application value.

The invention discloses a method for optimizing the pulling force of an arch bridge suspender rod for deviation correction in the construction process. A finite element model is established, and the material properties, geometric properties, boundary conditions and external load information in the finite element model should be consistent with the corresponding data in the design drawings ; Substituting a set of initial tensile forces of suspenders into the built finite element model for formal analysis in the construction stage, and obtaining each initial value vector; establishing an optimization model, and substituting each parameter into the optimized model to obtain the final tensile force. Through the timely correction of the measured weight during the construction process, the present invention realizes that the suspender is only stretched once, and no adjustment is required after the bridge is completed, and at the same time ensures that the tension of the suspender varies evenly and is small during the hoisting process; compared with the traditional calculation of tension method, this method does not require repeated iterations, avoids cumbersome calculations, and can obtain the pulling force results at one time. The invention is applicable to arch bridges with different construction sequences and spans, and has a very wide application range.

The invention discloses a method for controlling the hoisting displacement of an arch bridge lattice girder eliminating the influence of temperature. Taking the arch bridge with suspenders as the engineering object to carry out displacement control in the process, by introducing a temperature correction factor, the displacement of the hoisting construction of the arch bridge lattice girder is controlled, so as to eliminate the influence of temperature on the displacement of the lattice girder and reduce the temperature of the hoisting lattice girder The least impact is used as the objective function, and the displacement of the controlled bridge is closest to the reasonable bridge state as the constraint condition for analysis, which solves the problem that the displacement of the lattice girder is not easy to control due to the influence of temperature, and avoids the unevenness of the bridge deck and the driving comfort It greatly shortens the construction period of arch bridge lattice girder hoisting, reduces the risk of being forced to choose night construction, saves economic costs, has broad promotion and application prospects, and brings huge economic benefits. benefit.

The invention relates to a computing method of dynamic response under nonuniform excitation of an overline overbridge. The computing method of dynamic response under the nonuniform excitation of the overline bridge relates to the computing method of dynamic response of the overline pedestrian overbridge under the action of the nonuniform excitation of a main-line train, the dynamic response of the overline pedestrian overbridge serves as a target value, considering that the nonuniform excitation is generated at the position of a bridge pier of the overline pedestrian overbridge during the high-speed running process of the train, the equation of motion of the overline pedestrian overbridge under the action of the nonuniform excitation is deduced, and the response of the overline pedestrian overbridge under the action of the train can be obtained according to a numerical integration. According to the computing method of dynamic response under the nonuniform excitation of the overline bridge, the analytic method of the nonuniform excitation is brought out creatively to be used for calculating the vibration response under the nonuniform excitation acting on the position of the bridge pier of the overline pedestrian overbridge when the main-line train passing through at a high speed under the overline pedestrian overbridge, the computing method of dynamic response under the nonuniform excitation of the overline bridge is suitable for dynamic response analyses of all overline pedestrian overbridges under the action of the main-line trains and has a comparatively large practical engineering application value and innovativeness.

The invention relates to a calculating method of a fresh return air mixed type air adjusting system with a fixed secondary mixing ratio. The method comprises the following steps of: determining the dry-bulb temperature and relative humidity of an indoor design state point, the dry-bulb temperature and relative humidity of an outdoor design state point and the blowing temperature difference corresponding to the system design precision by determining the design calculating cold load and the design calculating wet load architectural indoors, wherein the fresh air percentage and the fixed secondary mixing ratio are target variables; acquiring the numerical values to calculate state parameter values of the indoor design state point, the outdoor design state point, a blowing state point, a primary mixing state point, a secondary mixing state point and state points of a dew point of a machine; and establishing a calculating mathematical model to calculate the general air volume, the fresh airvolume, the secondary mixing air return amount, the primary mixed return air amount and the primary mixed air volume of the system as well as a cooling capacity, quantity of reheat and refrigerationwater amount design numerical values needed by system design. The calculating method provided by the invention simplifies system control and operation complexity, and has relatively wide actual engineering application value.

The invention belongs to the field of the digital speed measuring technology and particularly relates to a median-value average filtering principle-based digital speed measuring method, wherein a speed feedback value is resolved based on the displacement. According to the median-value average filtering principle-based digital speed measuring method provided in the invention, firstly, the number N0of sampling points is selected, and a median-value average filtering-based digital speed measuring scheme is determined. The speed measuring scheme is subjected to mathematical simulation test. In this way, whether the signal characteristic and the phase margin characteristic of the speed measuring scheme meet the requirements at the same time or not can be verified. After that, the entity test is carried out on a motor connected with an absolute displacement sensor, wherein whether the characteristic of the speed feedback signal of the motor and the characteristic of the phase margin of thecontrol loop meet the requirements at the same time or not are verified. According to the invention, the method overcomes the defects of a traditional method in an initial operation stage and reducesthe resolution error. Meanwhile, the introduced phase lag is reduced. The control characteristic in the initial acceleration stage is improved. The method is suitable in all application scenes whereincorresponding speeds need to be resolved by using linear displacement values or angular displacement measurement values. The method has great practical engineering application value.

The invention relates to a high-temperature-resistant filling glue for packaging temperature-measuring crystals. The high-temperature-resistant temperature-measuring crystal filling glue of the present invention is composed of sodium silicate, silicon dioxide, zirconium oxide, titanium dioxide, and ethanol with a concentration of 50%, wherein the mass ratio of the sodium silicate is 19-21%. The mass proportion of silicon dioxide is 34-36%, the mass proportion of zirconia is 24-26%, the mass proportion of titanium dioxide is 14-16%, and the mass proportion of ethanol with a concentration of 50% is 4-6%, the sum of the contents of each component is 100%. The high-temperature-resistant temperature-measuring crystal filling glue of the present invention can encapsulate the temperature-measuring crystal, can work in an environment of 1300° C., and effectively protects the temperature-measuring crystal of the crystal so that it does not detach, so that the temperature-measuring crystal realizes the temperature measurement function.

The invention discloses a lifting displacement control method of an arch bridge lattice girder with little construction disturbance. By establishing a finite element model, the material properties, geometric properties, boundary conditions and external load information in the finite element model should be consistent with the corresponding data in the design drawings Consistent; Substituting a determined set of suspender initial tension into the built finite element model for formal analysis at the construction stage to obtain each initial value vector; establishing a construction displacement control system, substituting each parameter into the construction displacement control system to obtain the final bridge grid beam displacement. The method proposed by the invention achieves the effect of small construction disturbance by controlling the minimum displacement change in the construction process, and realizes that the displacement of the lattice girder bridge segment meets the design requirements, and the result is reliable; it ensures that the displacement change of the control point of the lattice girder is minimal during the construction process. Smooth, reducing the risk of large structural deformation during construction, improving construction efficiency, and realizing high-precision control of displacement during construction.