Advanced Materials Research Vols. 594-597

Abstract: Dynamic response of an elastic-supported bridge under speed-varied moving loads was investigated. A mathematical model of vehicle-bridge coupled oscillation for an elastic-supported bridge was built up by means of 1/4 vehicle model (Mass-Spring-Mass) and Euler-Bernoulli beam theory. And then dynamic equations of vehicle-bridge coupled oscillation in matrix form were established using two former orders general coordinates of an elastic-supported beam and model superposition method. The influences of vehicle-bridge coupled vibration model, elastic-supported stiffness, entrance speeds and acceleration /deceleration of moving loads on the dynamic responses of bridges were studied. Vehicle-bridge coupled vibration model based on 1/4 vehicle model can more accurately describe the dynamic characters of bridges than that based on constant moving force model. Elastic-supported stiffness only has an impact on the fluctuation amplitudes of dynamic responses. The vehicle-induced impact factor is dependent on the entrance speeds, acceleration/deceleration of moving loads and elastic-supported stiffness.

Abstract: Systematically analyzes the basic principle, calculation methods and control standards of the noise metrics of the world's major countries and regions. A series of experiments were taken on based on the noise monitoring data of a large busy airport. Through the experimental analysis demonstrated the similarities and differences of the airport noise metrics, pointing out that the existing airport noise metrics are not complete and need improvement.

Abstract: The excitation mechanism of bundle conductors' sub-span oscillation was introduced 、 the influencing factors of bundle conductors' sub-span oscillation are analyzed and the control computation theory of bundle conductors' sub-span oscillation was summarized. Then listed a number of anti-vibration measures of bundle conductors’ sub-span oscillation and proposed the methods of optimization arrangement about bundle conductors’ sub-span oscillation.

Abstract: Wind turbine tower structure system’s natural vibration properties have important effects on the system of wind power tower wind vibration and seismic response, especially the low order modes often plays a control function. How to calculate tower system vibration characteristics correctly and effectively in the design phase has important practical value. In this paper, some practical analytic solutions formulas were deduced on considering the simplified model using Rayleigh quotient method. Moreover, the results of a tower frequency and mode which were calculated by these formulas were compared with the continuous distribution parameters system’ theoretical solution and FEM method’s solutions. Analysis show that: these natural vibration properties practical analytic solutions formulas of a wind turbine tower about simplified model are useful and precision in a tower design, especially suitable for cone cube tower.

Abstract: High sound insulation performance of a wall is one of the significant goals of the architecture design. For exploring a reliable sound insulation prediction method to a single-leaf wall, this paper introduces the coincidence effect in the calculation. This method can predict the wall’s sound reduction index easily, and depict the coincidence effect of a wall especially. Meanwhile, it is shown that the prediction method might be applied to the practical building acoustic design.

Abstract: Statistical energy analysis (SEA) is utilized to model sound transmission through a double -leaf lightweight. Calculating the sound insulation by this method and comparing with the measured data have shown that the prediction model may generate a certain difference between the prediction and experimental data, this method, moreover, might further solve the problem of the sound insulation of the complex wall structure by optimizing the configuration of the enclosure structure.

Abstract: The Apparatus for measuring road roughness based on inertia benchmark are usually used with method of “calculation amendment”. The exquisite vibration of sprung mass and double integration of acceleration can bring error to measuring result. The amelioration was took to this kind of device by adding a mass block called measuring benchmark. Vibration characteristic was analyzed through vibration equation. To reduce the error, the perfect combination of system parameters was found to minish the amplitude of measuring benchmark. The analysis indicated that when selecting appropriate system parameters the dimensionless amplitude can be tend to “1”.

Abstract: Abstract：In order to study the thermal conductivity of ER in shock absorber, the AL2O3 and TiO2 ultrafine particles silicone oil ER are prepared to the different weights and been researched by experiment. Experiment result indicated: in the 5 mm scope of the electrode plank, the voltage from zero to three thousand, the thermal conductivity of ER fluids go up linear with the voltage growing, but the range is smaller; from three thousand to four thousand and five hundred voltage, the thermal conductivity of ER fluids go up with the voltage quickly. Under the high electric voltage, the ultrafine particles are polarized, the plus and minus particles are drawn each other, the particles are put in order and increasing the thermal conductivity.

Abstract: Traditionally, it is usually depended on engineers’ personal experience and habits to establish the strata layers on the basis of the original data when they doing the desk studies of a site investigation work, which are greatly subjective and nondeterministic. A method in combining the fuzzy cluster analysis and fuzzy pattern recognition is presented to classify stratum. Firstly, the sample integration is classified by adopting clustering analysis method. The fuzzy model is set up for different degree. Afterwards, the undetermined forecasting sample is predicted by applying fuzzy pattern recognition. Through actual validation, the reliability of the prediction is tested and verified.

Abstract: The paper establishes the ship-bridge collision early warning model on the basis of Fuzzy Theory and neural network method, puts forward the basic principles and concrete process of the ship-bridge collision early warning method. The model and calculation method applied in VTS after test and verification, it can achieve the practical accuracy and effect and finally achieve the active ship-bridge collision early warning.