Through the test of 12 reinforced steel fiber high-strength concrete beams, the influence of steel fibers on the crack bending moment of the positive section of reinforced high-strength concrete beams was analyzed. The experimental results show that the addition of steel fiber improves the cracking bending moment of the positive section of the steel high-strength concrete beam, and the increase trend is increasing with the increase of the volume rate of steel fiber, and the increase range is between 40%~100%. The reinforcement ratio of longitudinal rebar, the height of the beam and the strength grade of the rebar also have an impact on the cracking and bending moment of the rebar high-strength concrete beam. The cracking moment increases with the increase of the reinforcement ratio of the longitudinal rib and the decrease of the cross-sectional height. Combined with the current relevant specifications, the calculation formula of the cross-section resistance to the influence of plasticity of reinforced steel fiber high-strength concrete beam and the calculation formula of the cracking bending moment of reinforced steel fiber high-strength concrete beam are proposed, and the correctness of the formula is verified by test data.

Through the test of a new composite structure model for multi-storey housing under vertical loading, the stress, cracks, deformation and failure patterns of beams, columns and supports during the normal service stage and bearing capacity limit state of composite structure were studied. The results show that when the beam and column cross-section is 250 mm×250 mm, the support cross-section is 120 mm×120 mm, and the bearing area is 4.2 m× 4.2 m, the cracks and deflections of the beams and columns are much smaller than the concrete specification limits when the load reaches the standard value and design value of the general residential vertical load. The failure form of the composite structure under vertical load is the beam hinge mechanism system. And it is recommended that the height of the beam should be 1/14~1/10 of the actual span.

Aiming at the requirements of limited ductility of components in low-medium seismic damage areas, two new structural forms of reinforced concrete beam and column joints are proposed: oblique steel bars are added in the node area, or the main steel bars of the beam are bent in the node area. They can not only meet the requirements of limited ductility, but also avoid dense reinforcement in the node area. The repeated loading of four high-strength concrete beam and column joints at low cycle shows that the ductility of the two new joints can be improved, and the displacement ductility coefficients of the joints are increased from 2 to 4.2 and 3.3, respectively. The strength of the specimen with oblique steel bar can be increased by 5% in the nodal area, so it is the best joint construction form for the node with limited ductility requirement.

Using the large-scale general finite element program SAP2000, the spatial finite element calculation model of the steel structure of the string support dome roof of Anhui University gymnasium was established. According to the basic principle of static elastoplastic (Push-over) analysis, the elastoplastic ultimate bearing capacity of the roof steel structure under the combination of the two most unfavorable working conditions is calculated in detail. The calculation results show that the Push-over analysis method can find out the weak part of the structure where the plastic hinge first appears, and obtain the nonlinear load-displacement curve of the structure. Under the combination of the most unfavorable load conditions, it can be calculated that the elastoplastic ultimate bearing safety factor of the roof steel structure is 2.33, and the structure meets the safety requirements.

According to the dynamic characteristics of the large curvature bending steel box girder bridge, the single girder model, the beam lattice model and the plate element model were established through the large finite element program, and the numerical simulation analysis was carried out, and the modal test of the indoor model was carried out by the force hammer impact method, and the test results were compared with the numerical analysis results. The results show that the single girder method is not suitable for calculating the transverse mode, and the ordinary beam lattice method can better simulate the dynamic performance of the vertical and torsional bent box bridge, but the conversion relationship of the transverse stiffness in the static calculation of the main beam should not be considered.

Zhanhe Bridge, Chengdonghe Road, Pingdingshan City, is a reclining reinforced concrete box rib arch bridge, the inner arch of the bridge is tilted outward, the outer arch is tilted inward, and the combined arch rib is combined with tie beam and beam to form a spatial structure system. This bridge type is rare, and in order to understand the dynamic performance of this bridge type, it is necessary to analyze the spatial dynamic characteristics of the bridge. ANSYS software was used to establish the finite element calculation model of the bridge, and the vibration period and mode shape of the bridge in the first 15 steps were calculated. The calculation results show that the stiffness inside and outside the arch rib surface of this bridge type is quite different, the lateral stiffness is weaker than the vertical stiffness, and the lower level of the bridge is dominated by the lateral vibration of the arch rib. The self-vibration period of the bridge is large; The bridge mode shape is relatively dense.

In view of the fact that in the design of the main cable, the high safety factor is used to avoid the detailed secondary stress analysis and the bearing capacity of the main cable is not fully utilized, a more detailed analysis of the secondary stress of the suspension bridge is attempted. The secondary stress of the main cable of the suspension bridge due to the difference in wire strand length, the elastic modulus of steel wire and the bending of steel wire was analyzed, and the corresponding empirical calculation formula was given. The secondary stress caused by the change of cable angle is analyzed by the previous calculation method, and the theoretical analysis and formula derivation are carried out for more general situations, and the calculation algorithm is given. The secondary stress caused by the change of cable shape is decomposed into three parts: porosity difference, cross-section characteristic difference, and cross-section shape difference. The secondary stress caused by the circular section of the main cable out of the main saddle to the circular section of the first cable clamp was analyzed. Finally, combined with the example of calculating the secondary stress of the main cable of a long-span suspension bridge in China, the occurrence of the secondary stress and the influence of the secondary stress on the structural safety are analyzed, and the safety factor of the case is analyzed according to the calculation method of the main cable of the long-span suspension bridge in the United Kingdom, Japan and Denmark, and its safety can be guaranteed.

In order to verify whether the small-particle size breeze fossil material with poor particle gradation in the excavation area of the landslide body in the reservoir area can be used as the filler of the main rockfill area of the concrete panel rockfill dam body in the large water gou reservoir, the on-site compaction test of this kind of stone was carried out. Corresponding to the maximum compactness that can be achieved in the field test, the denaturation modulus Es, Poisson’s ratio v, permeability coefficient K and triaxial fast shear mechanical parameters c of such stones in this state were obtained through indoor test ψ, and the dynamic response analysis of the dam under the condition of magnitude 7 seismic intensity was carried out by the one-dimensional shear layer method according to the indoor and outdoor test parameters, and the maximum dynamic shear strain and shear stress reaction distribution of the dam were obtained, and the absolute maximum dynamic shear strain in the dam body was 4.41×10-3. The absolute maximum dynamic shear stress is 40kPa, which is much less than the strength of the dam itself, which verifies that this kind of stone can be used as the filler of panel rockfill dams, and broadens the selection range of filling materials for concrete facet rockfill dams.

The analysis method of semi-active control of the wind vibration reaction of the giant-subtype control structure system using magnetorheological damper is studied, the vibration control equation of the structural system under random pulsating wind load is established, the computer simulation of the pulsating wind load is carried out by the random vibration theory, and the limited Hrovat optimal semi-active control algorithm based on the classical optimal control theory is used to study the control of the wind vibration reaction of the structural system. The analysis shows that after semi-active control of the giant~subtype control structure system by magnetorheological damper, the vibration damping rate VAR of the displacement and acceleration control at the top layer of the main structure is 29.65% and 68.09%, respectively, and the vibration damping rate VAR of the acceleration control of the second substructure and the top acceleration control of the third substructure is 2.3% and 40.18%, respectively, which effectively reduces the wind vibration reaction of the structural system.

In order to separate and purify the chlorinated cyclohexane in the multi-component mixture, a two-step rectification method is adopted. First carry out atmospheric pressure batch distillation of the mixed liquid, distill most of the cyclohexane, cyclohexene and a small amount of impurities, complete the rectification, and filter the column kettle liquid, and obtain the product, according to the purity of the product, and then vacuum rectification column liquid, directly distill the chlorocyclohexane. The influencing factors in the distillation process were investigated: pressure, reflux ratio, heating amount, and full reflux start time. Using the variable reflux ratio operation, the best experimental conditions obtained at the top of the tower are: heating voltage 160V, full reflux 30 min, variable reflux ratio 4.5~3~1.5.Operating conditions for purification of chlorocyclohexane: vacuum degree is 0.068~0.072 MPa, purity reaches 99.06%.

The enzymatic hydrolysis conditions for the extraction of dioscin by compound enzymatic method were studied, and the extraction effects of compound enzymatic method, cellulase method, amylase method and glycated enzyme method were compared. The experimental results showed that the cellulase method had the highest purity. The compound enzymatic product has the highest yield, and has the characteristics of short time and low temperature in terms of enzymatic hydrolysis conditions. Finally, the compound enzymatic method was determined as the best method, and the optimal enzymatic hydrolysis conditions for extracting diosca saponin were as follows: enzymatic hydrolysis time was 16 h, enzymatic hydrolysis temperature was 35°C, enzymatic hydrolysis PH value was 5.0, and the enzyme amount per gram of yellow turmeric was 0.04g.

In view of the shortcomings of controlling the quality of oleanolic fruit acid by acid-base non-aqueous solution titration method, and the large error is large, the content of oleanolic fruit acid in oleanolic acid tablets was separated and determined by high performance liquid chromatography. The chromatographic conditions were: the column was ZORBAX SB-C18 column, the mobile phase was methanol-water (90:10), the flow rate was 0.8 mL·min-1, the detection wavelength was 215 nm, and the column temperature was 27 °C. Under this condition, the oleanolic acid was in the range of 0.025 2~2.520 0 mg·mL-1, and the linear relationship was good, r=0.999 7, the average recovery rate of oleanolic fruit acid was 99.4%, peaking at about 13 min, and RSD=1.9%. The quality of the preparation can be effectively controlled.

The extraction process combining cellulase enzymatic hydrolysis pretreatment and water leaching was used to extract total flavonoids from sesame leaves, the content of total flavonoids in sesame leaves was determined by spectrophotometry, and the influence of various factors on the yield during the extraction of total flavonoids in sesame leaves was studied, and the optimal process conditions were as follows: material-liquid ratio was 1:60. pH 5.0; Enzymatic hydrolysis temperature 45 °C; Enzyme concentration 3 U/mL; Enzymatic hydrolysis time 2.5 h; Leaching time 2.5 h; Leaching temperature 80°C; The extraction yield of total flavonoids from sesame leaves reached 12.31%.

Ag-52%Ge (mass fraction) sub-eutectic and Ag-15%Ge (mass fraction) hyper-eutectic alloy microgravity tests were carried out by 21m long drop tube device, and the microstructure of the solidified alloy spheres was analyzed, and the structure of the same composition alloy under conventional solidification conditions was compared. The results show that the down-tube experiment can make the alloy obtain a large subcooling, so that the Ag-15%Ge (mass fraction) subeutectic alloy Ag primary return solution phase is significantly refined, and the dendrite characteristics disappear and change into fine irregular blocks or approximately spherical shapes. The microstructure and quantity of Ge primary phase in Ag-21%Ge (mass fraction) supereutectic alloy were refined and increased, but the lateral growth mechanism of Ge phase of facet crystal was not changed.

According to the principle of thermal continuous casting technology, fully considering the three-way transmission process of metallurgical unit, the heat transfer of some small parts was approximated, and the physical and mathematical models of the two-dimensional steady-state temperature field of the solidification process of thermal continuous casting were established. The application of process parameters such as calculating mold outlet temperature, cooling distance, drawing speed and water spray cooling intensity was compiled, and it was iteratively run in the VC++6.0 environment, and the influence degree of the above process parameters on the position of the solid-liquid interface of the casting billet was theoretically obtained. A number of pure copper hot type continuous casting experiments were carried out, and the calculation results were in good agreement with the measured values and experimental results reported in the literature, and also showed the correctness of the two-dimensional model.

Ensuring the service life of pavement structure is an important research topic in the field of road engineering. On the basis of the previous research results, by introducing dynamic reliability index and pavement structure durability design coefficient, a cement concrete pavement structure durability design verification model is established, which is coordinated with the design expression given by the current < highway cement concrete pavement design code > in China, which is convenient for practical application and verified with application examples.

A linear reference system considering the linear characteristics of highways is proposed, which aims to solve the problems of spatial data redundancy in highway database and easy deviation of highway events on small scale electronic maps. By identifying highway alignment, compressing redundant data and assigning linear coordinates, a linear reference reference is established, and the corresponding linear reference algorithm is established to dynamically establish the relationship between highway events and two-dimensional geodetic coordinates. The practical application in highway management shows that this reference system has the characteristics of simplicity and high precision, and can better meet the actual engineering requirements.

Starting from the automobile driving theory, taking the Jiefang CA141 truck as the standard model, the dynamic nature of the car, the force and motion equation of the vehicle on the road are analyzed, and the various influencing factors such as air resistance, altitude and vehicle load are fully considered when the car is exposed to the uphill and downhill, and the method of determining the maximum slope length limit of mountain roads is discussed. Based on the analysis results, the suggestions that the maximum slope length limit should be appropriately relaxed > the technical standards of China’s < highway engineering are put forward, and the recommended value for modifying the maximum slope length limit of mountain roads is given (and the correctness of the analysis is verified by experiments) for designers to refer to in the design process.

95 connecting rod is an important part of 95 series diesel engine, in order to evaluate the reliability of its connecting rod, the stress and processing error analysis of the connecting rod is first analyzed by finite element and electrical measurement technology, and the mean value and standard deviation of the working stress are determined. Then, the fatigue test of the lifting method of the connecting rod was carried out with the load as the controlling factor. Experiments show that the fatigue strength of the connecting rod conforms to the Weibull distribution, and three distribution parameters are obtained. Finally, the reliability theory is used to discuss the failure probability of connecting rods. After analysis and calculation, the rated load of 3 connecting rod is far lower than the minimum fatigue strength, the probability of failure is zero under normal circumstances, and it has sufficient fatigue strength reserve, which can meet the requirements of diesel engine to increase speed and improve performance, which shows that it is feasible to use the lifting method to find the fatigue strength of components and its distribution law, and it is a reliable and effective method.

Mckibben pneumatic artificial muscle is a sports engine excited by air pressure, which can output sufficient pulling force and has a certain degree of compliance. A new robotic elbow joint was built, the joint structure evolved from the human elbow joint, driven by two Mckibben pneumatic artificial muscles set up against each other, the telescopic movement of the muscle pair caused the joint to rotate; The relationship between joint angle and artificial muscle contraction length, as well as several possible scenarios of maximum rotation angle, the maximum possible rotation angle is derived, the influence of joint structural parameters on the maximum rotation angle is discussed, and the robot joint and human joint are compared.

The performance of the new casing exhaust pipe cyclone was studied by CFD technology. In the study of two-phase flow, a random orbital model with interphase coupling is adopted. The results show that the static pressure distribution of the flow field of the new cyclone is more conducive to preventing the backmixing of the air flow in the ash hopper than the static pressure distribution of the ordinary type flow field. Two kinds of purified gas with different dust content can be discharged, the dust content of the purified gas discharged from the inner exhaust pipe is lower than that of the outer exhaust pipe, and decreases with the decrease of the diameter of the inner pipe, and the total pressure drop of the inner exhaust pipe is larger than that of the outer exhaust pipe, and gradually decreases with the increase of the diameter of the inner pipe; By changing the diameter of the inner exhaust pipe, the dust content of the gas discharged from the inner exhaust pipe can be controlled, which is convenient for subsequent grading treatment.

At present, several existing RBF network training methods are proposed for complex samples with random noise training speed is too slow and the classification performance is unstable, according to the principle of minimum relative entropy, an improved RBF network training method-output-input clustering method is proposed. This method is used to train the rotating machinery fault samples and compare with other methods, and the results show that the training method takes a short time, has a simple network structure, and is less affected by noise. The created network is applied to fault diagnosis, and the examples show that the network diagnosis results trained by this method are accurate and have good application prospects in fault diagnosis.

On the basis of analyzing the advantages and disadvantages of MATLAB and VB development languages, the data exchange and integrated development of MATLAB and VB are realized by elaborating and using ActiveX automation technology, using Visual Basic 6.0 language and object-oriented programming ideas. The mathematical model of typical circuit was established by MATLAB, and the dynamic characteristics of the proportional valve circuit were analyzed and the visual results were given. The advantages of the two make the software development of proportional speed control loop more concise and efficient.

With the large-scale adoption of switchgear, the structure of urban distribution network is becoming more and more complex, and the reliability calculation of complex power grid can be simplified by using object-oriented processing methods to equirate the reliability of distribution network. According to the characteristics of radial pattern of distribution network, the tree storage structure is used to calculate the distribution network and the calculation program is compiled, and the feasibility of the algorithm is verified by typical examples, and the difference in the influence degree of various technical measures on the reliability of the distribution network is obtained through the calculation and analysis of six wiring schemes of typical examples, which provides a basis for improving the reliability of the distribution network.

There is a large error in the direct use of FFT for power system harmonic analysis, and the interpolation correction algorithm can better improve the measurement accuracy. In view of the excellent performance of Blankman-harris window in suppressing long-range leakage in spectral analysis, the principle of double spectral line interpolation correction is adopted, the Blankman-harris window double spectral line interpolation correction formula is derived, and the MATLAB polynomial approximation function is used to find a concise and practical approximation polynomial based on the Blankman-harris window interpolation correction formula. Simulation analysis shows that the algorithm of modified polynomial is easy to implement and has high accuracy.

By introducing the concepts of vector value multi-resolution analysis and orthogonal wavelets of multiple vector values, using the theory of imitation vector filter and Fourier transform, the sufficient conditions for the existence of orthogonal wavelets of multiple vector values are obtained, and the orthogonal wavelet function of multiple vector values is constructed by using multi-resolution analysis methods and matrix theory, and a class of orthogonal wavelets with tight support vector values is given a number of orthogonal scale functions suitable for certain conditions, and a construction algorithm for orthogonal wavelets of multiple vector values is given, and a corresponding construction example is given.

The unified formula of the higher-order derivative and the original function studied in literature [1] is extended to the special function with a more complex structure by mathematical induction, and more widely used results than those in literature [1]. The results show that the inverse operation of the higher-order derivative and the original function can be unified in some complex special functions. By using this result, you only need to analyze the derivative of this complex special function and its own structural characteristics, and you can quickly obtain the results of the higher-order derivative and original function representing the complex special function with the same formula without analysis.

According to the characteristics of bill of quantities quotation bidding and project payment cycle payment, based on the influence of time value of funds on project contracting income, and using the principle of unbalanced quotation and planning theory, a linear programming model and computer algorithm to optimize project bidding and quotation are proposed, which can increase the unit price of early construction projects and reduce the unit price of later construction projects, so as to increase the net present value of project contracting income while keeping the total static bidding quotation unchanged, so as to improve the actual income level. Reduce the static total quotation of project bids while keeping the present value of earnings unchanged to improve the winning rate.