Four steel bars with diameters of 8 mm, 12 mm, 16 mm and 500 MPa were tensile tested and nine small prisms of 4 mm× 9 mm × 150 mm were tested for axial compression short columns. The results show that the measured yield strength exceeds 150 MPa, the uniform elongation reaches more than 450%, and the ductility is good. The bearing capacity of the axial compression short column can be calculated according to the formula specified in the current specification, when the compressive strength of the steel bar is 500 MPa, the ratio of the test failure axial force to the calculated value is above 10.450, and there is a good safety reserve. The axial compression short column equipped with 1 MPa grade steel bar has good force performance, and the strength of steel bar and concrete can be well exerted.

The bender is to realize the friction loss of the prestressed ribs after passing through the bending at 13° of the prestressed reinforcement of the pre-tensioned line, analyze the main factors affecting the friction loss of the steel strand, and put forward the calculation method and related suggestions of the friction loss of the prestressed rib of the bender used in the test. The test results show that the friction loss of the steel strand is proportional to the bending angle and linear with the tension control stress, and the extrusion stress of the steel plate above the hole of the steel strand of the bender is only 2.1% of the tension control stress, indicating that the bender has a reliable strength and safety guarantee basis.

Through the experimental study of the stress performance of the 12 m span GRC special-shaped inner mold folded linear prestressed rib box girder, the maximum bearing capacity of the box girder was determined, the development of cracks and deflections of the box girder under various levels of load, as well as its failure form and failure characteristics, were analyzed, and the test results were compared with the results calculated according to the current specifications. The results show that the stress performance of the test beam is good, the inner mold and the beam form a unified force whole to work together, and when the load reaches 207% of the design failure load, the failure still does not occur, and there is sufficient safety reserve. Design in accordance with current bridge design codes to meet engineering requirements. GRC thin-walled cylinder core is a promising inner mold for small-span bridges.

In order to study the influence of carbon fiber cloth reinforcement on the performance of frame structure, the test specimen of reinforced concrete frame structure reinforced with carbon fiber cloth was designed according to the 1∶3 scale model, and the experimental research analysis under vertical load was carried out. The test results show that the U-hoop with large cracks damaged concrete structure and small pasting spacing can effectively inhibit the crack development. Pasting carbon fiber cloth at the bottom of the beam can not only effectively delay the yield of the steel bar but also greatly improve the ultimate bending bearing capacity of the beam under the condition that the bonding anchorage is satisfied. Due to the restraining effect of carbon fiber cloth, the sectional bending stiffness of the reinforced rear beam is improved. The tensile force of the beam after the reinforcement of the carbon fiber cloth is borne by the steel bar and the carbon fiber cloth, the role of the carbon fiber cloth after the yield of the steel bar is significantly increased, and the main tensile force is borne by bearing, in order to prevent the carbon fiber cloth from suddenly pulling off, it is necessary to consider its effective utilization rate.

By simulating the unstable seepage field of the foundation pit during precipitation, the variation law of water pressure acting on the cement-soil retaining wall during precipitation is analyzed, and the influence of unstable seepage on the stability of such retaining wall is discussed. The analysis results show that the water pressure around the wall decreases with time, while the sub-coefficients of overturning resistance and horizontal sliding resistance increase continuously, and are significantly larger than the calculation results without considering seepage, two-dimensional stable seepage and one-dimensional simplified seepage. Therefore, the influence of unstable seepage should be considered in the design of foundation pit support.

Aiming at the research status of the calculation method of the ultimate bearing capacity of horizontal anchor plates, considering the failure surface of the logarithmic helix and combining the characteristic line theory, a new calculation method for the ultimate pull-up force of shallow buried strip plate is proposed and a program is compiled. In this method, the traditional limit equilibrium method and the Soxhlet slip line method are coupled, and in order to avoid the intersection of the center region and the slip line field, the calculation mode of differential from the failure to the bottom plate is adopted. For non-cohesive soils, the results obtained by comparing with the experimental data of predecessors and the results obtained by Meyerhof and Adams theory show that the proposed method is correct and feasible.

A typical ultra-long high-rise building structure is selected as the calculation example, and the finite element method is used to calculate the temperature effect of the overall structure of the ultra-long high-rise building by considering the two calculation conditions of seasonal temperature rise and seasonal cooling. By comparing and analyzing the calculation results of structural temperature deformation and internal forces or stresses of various components under two calculation conditions, the commonality and difference of temperature effects caused by seasonal temperature differences in the structure of the super-long high-rise building at different times are found, and the adverse effects of seasonal cooling conditions on the super-long high-rise building structure are given.

Inositol was studied by differential scanning calorimetry (DSC) and thermogravimetric method (DTA-TGA): the melting point of inositol was 227.67 °C, the heat of melting was 256.67 J·g-1 by DSC method, and the decomposition temperature of inositol was above 300 °C by combined analysis of DSC and DTA-TGA. At the same time, the experimental conditions for the determination of inositol by DSC-60 differential scanning calorimeter were determined, that is, under the conditions of temperature increase rate of 10°C·min-1 and nitrogen flow rate of 30 ml·min-1, a good DSC curve could be obtained by analyzing inositol samples.

The relationships between glass transition temperature (Tg), crystallization temperature (Tx) and reduced glass transition temperature (Tg/Tm) and electron concentration value (e/a), atomic size criterion (λn), mixed enthalpy (△Hchem) and mixed entropy (△S) in Zr-Al-Co alloy series were analyzed. The results show that the relationships between Tg, Tx and Tg/Tm and e/a, λn, △Hchem and △S can be studied by multiple regression, and the regression results are significant. Through the F-test, e/a and λn are eliminated, and only △Hchem and △S are sufficient to explain the response variables Tg, Tx and Tg/Tm, and the method of simplifying the model is feasible. It is unreliable to use △S or △Hchem to explain the response variables Tg, Tx and Tg/Tm, and in some articles it is unreliable to use only △H to determine the amorphous formation ability.

The morphology (shape characteristics) of mineral aggregates quantified by contour shape, angularity and surface texture have a significant influence on the properties of asphalt mixtures. In order to study the influence of coarse aggregate morphology on the shear performance of asphalt surface layer, the coarse aggregate morphology was regarded as the primary factor, the shape parameters of coarse aggregate based on image were defined, and the shape parameters of five groups of coarse aggregates with different particle shape characteristics were obtained by using the prepared image processing procedure, and the influence of coarse aggregate morphological parameters on the shear strength of SAC-16 mixture was analyzed by uniaxial penetration experiment. The results show that various morphological parameters of coarse aggregate have different degrees of influence on the shear strength of the mixture, and the flatness ratio has the greatest influence on the shear strength, and the content of flat particles in the coarse aggregate must be controlled.

The road performance of nano-calcium carbonate-modified bitumen was studied, and the differential scanning calorimetric analysis (DSC) was used to test and analyze the nano-calcium carbonate-modified bitumen, and the high temperature stability and temperature sensitivity of nano-carbonate-modified bitumen were studied from the aspects of heat absorption and specific heat capacity, and the temperature stability improvement mechanism was discussed. Studies have shown that nano-calcium carbonate can improve the high temperature stability of matrix asphalt. The specific heat capacity has clear physical significance and convenient measurement, and the high temperature stability quality of bitumen can be evaluated.

Volume parameters are the basis of asphalt mixture design, but due to the absorption of asphalt by aggregate, the maximum theoretical density can neither be accurately measured nor accurately calculated, which affects the accuracy of volume parameter calculation. A test method for determining the effective density of aggregates by bitumen impregnation was proposed. The test results show that for the modified asphalt mixture, it is unreasonable to calculate the effective density of the aggregate according to the formula in the newly promulgated implementation specification, while the measurement results by asphalt impregnation method have good reproducibility, do not have high requirements for test conditions, and have little influence of test human factors. The effective density of aggregate measured by asphalt impregnation method can calculate the true value of the maximum theoretical density of asphalt mixture. The porosity composition of continuous dense grade asphalt mixture specimens is analyzed theoretically, a reasonable specimen density determination method is proposed, and the calculation formula of asphalt mixture volume parameters is proposed.

After the cement-based material is cured and matured in a suitable environment, the excess free moisture inside it will continue to volatilize into the air, and the material will transition from a saturated state to an unsaturated state, and its mechanical properties will change accordingly. Firstly, the development of the main mechanical properties of cement-based materials in the drying process is studied through physical experiments, and then the damage-elastoplasticity-drying coupling model is established to describe the mechanical behavior of cement-based materials at different saturations. The comparison of the model calculation results with the experimental data shows that the established model can well reflect the changes of the mechanical properties of cement-based materials during the drying process.

Due to the problems of non-contact ICPT, such as device aging, temperature change, load change, etc., the resonant frequency of the system will change, which will affect the realization of the zero-voltage switch (ZVS) and the power transmission capacity of the system. Taking the parallel resonant contactless power supply platform as the research object, the novel method of controlling the nonlinear variable inductance control frequency by double closed-loop control loop is adopted, and the stable control of the contactless power supply platform at the given resonant frequency is realized through the ingenious selection of circuit parameters. Both theoretical derivation and experimental results confirm the feasibility of the scheme.

A large number of test data show that the hysteresis curve of the lead-core rubber support is closely related to the loading time history. At present, the existing recovery force model of lead-core rubber support does not consider the strain hysteresis characteristics based on the loading time course, in view of this characteristic of the lead-core rubber bearing, the "flat ring" effect of the lead-core rubber support is proposed, and the "flat ring" effect of the shear elastic plastic "flat ring" effect considering the loading time course strain hysteresis characteristic is established according to the principle of double inflection point, and the proposed restoring force model is verified by static test. The experimental results show that the "flat ring" effect proposed by the author can well describe the strain hysteresis characteristics of the loading time history of the lead-core rubber support, and the "flat ring" effect recovery force model is reasonable and accurate, which is suitable for accurate nonlinear time history analysis.

Aiming at the characteristics of large-area multi-body contact and strong structural repeatability between cylinder and roller, the multi-body contact model of cylinder and roller is established by applying contact pseudo-unit and substructure technology, and the load caused by the weight of the kiln skin and lifting plate is automatically converted into the volume of its action area by defining the equivalent density, which reduces the workload of load processing. The numerical calculation results of the multi-body contact problem between the cylinder and the roller show that the pressure of the cylinder shell in the gear section is much greater than that of the cylinder shell of the cylinder segment, the strength of the cylinder shell of the gear section is weak, and the strength of the cylinder shell of the cylinder segment is somewhat surplus.

Based on the seismic response analysis method of long-span bridges, a spatial finite element model of dynamic analysis of cable-stayed bridges is established. Considering the influence of geometric nonlinearity on the dynamic characteristics and seismic response of the structure, a long-span prestressed concrete cable-stayed bridge was used as the research object, and the seismic nonlinear time history analysis of the bridge was carried out by direct integral method. According to the scheme design of the bridge, the dynamic characteristics of the structure under the connection mode of the two tower girder are compared, and the influence of pile soil effect on the seismic response of the structure is analyzed. The calculation results show that the influence of pile-soil interaction should be considered in the seismic design of long-span cable-stayed bridge. The calculation results of the artificial fitting ground motion and the measured ground motion records of similar sites are quite different, and the most unfavorable load should be taken in the seismic review.

Based on the improved AHP method and entropy method, a nonlinear objective programming method for determining index weights is proposed, which combines subjective and objective weight information, which can not only make full use of objective information, but also meet the subjective wishes of decision makers. At the same time, in view of the existence of many gray information in the optimization of bridge reinforcement scheme, gray correlation analysis is used to optimize the scheme. Finally, the rationality and practicality of the decision-making method are illustrated by engineering examples, which provides a new idea for the scientific decision-making of bridge reinforcement scheme.

Most of the existing literature research on the fracture problem of gradient materials assumes that the material properties are exponential functions or power functions of coordinates, and other function forms are rarely used. The author assumes that the reciprocal of the shear modulus of the functional gradient material is a linear function of the coordinates and the Poisson’s ratio is a constant, and the anti-plane crack problem of the functional gradient slats is studied. The Fourier integral transformation technology and transfer matrix method are used to solve the mixed edge value problem into a pair of singular integral equations, and the stress intensity factor of slab cracks under anti-plane loading is obtained by numerical solution of the singular integral equation, and the influence of crack relative size and material heterogeneity on the stress intensity factor is discussed.

Firstly, three traditional sensor optimization arrangement methods based on the data information maximization criterion are discussed, namely effective independent method, effective independent drive point-residual method and motion energy method. The first two are based on Fisher information array maximization, while the third is based on motion energy maximization. Then, the two comparison criteria are used to determine the optimal sensor setting method by using the minimum mean square deviation between the structural vibration mode and the three-spline interpolation mode and the best noise immunity. Numerical analysis shows that these three sensor optimization arrangement methods are effective, and the effective independent-drive point residual method has the best effect.

Based on the variable density topology optimization method and the finite element model of acoustic-structure coupling system, the vibration and noise reduction analysis of the aircraft cockpit simulated by the four-corner solid support box was analyzed. Through numerical simulation, the structure quality and stiffness characteristics are optimally configured so that the natural frequency of the structure avoids the excitation frequency, thereby avoiding resonance. By comparing the changes of the natural frequency of the structure and the influence on sound pressure before and after optimization, the feasibility and effectiveness of topology optimization in structural vibration and noise reduction are verified. This method has certain reference value for the design of vibration and noise reduction in aircraft cockpit.

The error energy caused by the 3D model transformation is minimally reflected on the embedded watermark. In order to make the embedded watermark robust to the topological transformation and geometric transformation of the three-dimensional model, a 3D geometric model algorithm based on the minimum mean square deviation is proposed, and the algorithm first sorts and selects the vertices of the three-dimensional mesh, and the principle of sorting and picking is to make the selected vertices have the smallest margin sum, that is, by optimizing the selection of the vertices of the <>D model mesh, the selected vertices are least affected by topological attacks; Then, the mean squared error energy of the selected vertex perturbation is calculated to embed the watermark into the space with the least influence of the error energy, so that the embedded watermark is least affected by geometric attack. Experimental results show that the algorithm has good resistance to geometric attacks and topological attacks.

The advantages of the joint station simulation exercise system using virtual reality technology were introduced, and the specific applications of key technologies such as 3D modeling technology, instantiation technology, texture mapping technology, LJOD technology, collision detection technology, and database technology in the system were expounded. From the three aspects of scene modeling, scene expression artistry and three-dimensional object motion simulation, the application and implementation of VR technology in the system are explained in detail by taking the free water remover scene as an example. In the application process of this system, the objects are vividly expressed, realistic, and the operation is real-time and effective, which can allow users to feel the actual environment and real operation immersively, and play a real role in the actual operation exercise.

Aiming at the key problems of the realism and real-time simulation of the classical particle system flame, a new flame drawing algorithm based on the particle system is given, the initialization of the particle attribute is determined by the emitter, and the update of the color, position, lifetime and other attributes of the particle is optimized, the movement change of the particle is controlled by the low pressure point, the particle is represented by the four-corner patch, combined with the texture mapping technology for three-dimensional flame rendering, and the texture adopts time-divided mapping to simulate the burning process of the flame. Experiments show that the algorithm simulates the movement and appearance of the flame, and real-time drawing speed can be obtained by using the standard graphics system on ordinary PC platforms.

A relatively mature rectangular micron flow channel (micro-channel) processing technology was introduced, and the rubber template was prepared on the silicon wafer by thick glue lithography process, and then the micron-level microchannel (height and width range 20~100μm) was made with polymer PDMS (polydimethylsiloxane, polydimethylsiloxane) on the template, and the geometric accuracy of the prepared microchannel was magnified by 20×100 times, and the flow characteristics were experimentally determined. Compared with the Poisu leaf theory formula (the pipe flow expression of the NS equation), it can be seen that the Poisu leaf formula is still applicable in rectangular microfluidic channels with the order of microns.

Seeking the optimal reservoir scheduling trajectory process line is a classic and difficult problem in reservoir optimal scheduling. Based on the analysis of the advantages and disadvantages of previous reservoir optimization scheduling models, this paper proposes a reservoir optimization scheduling model based on Particle Swarm Optimization (PSO), and solves the problem of strong constraint by introducing a penalty function. The optimal scheduling of a comprehensive utilization reservoir is studied as an example, and the calculation results of dynamic programming model are compared and analyzed. The results show that the particle swarm optimization algorithm is simple in principle, easy to program, occupies small computer memory, and has fast calculation speed, which is suitable for determining the optimal scheduling rules of reservoirs within the year.

From the perspective of spatial landscape planning, under the guidance of the basic concept of the relationship between art and nature and ecological coordination, the water and soil of the polluted land in the abandoned land are first restored through the combination of ecological technology and art. On the one hand, it is necessary to develop and transform the available land in various water spaces, and on the other hand, it is necessary to fully explore the historical and cultural value of abandoned plots. According to the current situation of the abandoned land, choose a suitable landscape transformation mode, or transform it into a green space, or change it into a cultural place, or cooperate with water remediation to become a public recreation site, or reuse the abandoned land through the reuse of the original buildings and structural facilities, and promote the renewal and development of the urban waterfront.