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The concrete decks in wide box composite girder bridge carrying vehicle load directly are easy to failure. So the decks in approach bridge of Jiubao Bridge are designed to renewable component. Several deck removal plans were put forward based on the structure characteristics of the Jiubao bridge. Spatial finite element model of the bridge was set up and the responses of approach bridge under different removal plan were analyzed. The analysis results show that methods proposed in this paper about deck removal in local position or in whole span are feasible; however different whole span removal method affect the mechanical behavior of the approach bridge heavily.

It has been proved by the seismologic observation of 5.12 Wenchuan Earthquake that a large number of shallow-buried depth mountain tunnels at the portal are underwent severe damage. Earthquake waves, especially Rayleigh waves may be a major factor causing the damage. The numerical model of the shallow-buried depth mountain tunnels by FLAC3D is establishes in this paper, and the dynamic responses of the shallow-buried depth mountain tunnels under the action of Rayleigh waves are simulated by loading on normal Rayleigh waves. The effect of different strength of surface waves is simulated by the in-site blasting tests. The dynamic responses of the tunnel lining under the action of Rayleigh waves are obtained by filtering and composition separation in order to discuss the incidence and mechanism of action. The results show that the dynamic responses of tunnel lining under the action of Rayleigh waves mainly focuses on the portal of tunnel, namely the buried depth and lengthways depth of the tunnel are 0~16m and 0~20m, the tunnel lining is damaged easily in the incidence, and the multiplicative effect of Rayleigh waves often occurs at the portal; beyond the incidence, Rayleigh waves attenuate rapidly and the dynamic responses of the tunnel lining decreases gradually, which has little effects on the safety of tunnel structures.

In order to explore the feasibility of a class of eutectic ionic liquids in soil heavy metal repair problems. The acetamide-alanine eutectic ionic liquid was prepared and its properties of density, viscosity, surface tension and electrical conductivity were measured, and it’s application effect of Cd²⁺ extraction in soil was studied. The results showed that the extraction amount of Cd²⁺ in soil by the acetamide-alanine eutectic ionic liquid with a concentration of 0.6 mol/L reached the maximum of 99.67%. The physical properties of a melamine-alanine eutectic ionic liquid having a concentration of 0.6 mol/L at a temperature range of 303.15 K-343.15 K were determined. The 0.6 mol/L acetamide-alanine eutectic ionic liquid was compared with the ionic liquid and the related organic acid aqueous solution prepared under the same conditions, and the acetamide-alanine eutectic prepared by the experiment was found to be eutectic. The ionic liquid has better extraction efficiency for heavy metal Cd²⁺ under the same conditions, and is a good soil heavy metal extractant.

This paper deals with the testing, isolating and diagnosis of construction machinery. Subsequently, the analysis of operating status, faulty mode and running parameter is carried out. The equipment implements the detection, processing, storage and alarming of the operating status parameters, such as temperature of cooling system, oil temperature, oil pressure, engine rotation speed, oil temperature of torque converter as well as oil level of sump and etc. Meanwhile, the real time fault alarm and historical data analysis results can also be performed and illustrated by vivid graphical interface. The embedded ARM microcontroller, which is the core module of the system, manipulates the data acquisition of operating parameters for the construction machinery. Application software of ARM chip processes the operating status parameters and accomplishes alarm and control operations under failure pattern of the machine. The failure data can not only be displayed and alarmed synchronously, but also can be stored for further fault analysis. The equipment can record various types of operating parameters, and is applicable to many different types of engineering vehicles.

Wind turbine gearbox is the key component. Because of alternating loads caused by gear engagement, variations of wind speed and fluctuation of load, it is prone to get fatigue damage, which lead to the high failure rate and low life. In this paper, obtaining the stress time histories through multi-body dynamics simulation, then base on the simulation data, statistical processing load time histories by used rain flow counting method, the last is that estimating fatigue life of components, combined with P-S-N curves of parts material and linear cumulative damage law. The fatigue life prediction of each component in gearbox would be implemented by matlab programming. Through the fatigue analysis of a megawatt-class wind turbine gearbox transmission chain, the design was verified feasibility, but not economic, and it show that this method has certain reference value and potential for improvement.

Characteristic parameters of joint surfaces are needed in kinetic modeling of the motor frame while analyzing its vibration behavior. In this paper, research on tangential dynamic characteristics of mechanical joint surfaces in the motor frame is executed. In order to get the tangential contact stiffness and contact damping of interfaces in the motor frame under different joint conditions, an experimental method is proposed according to the structure feature and running condition of motors. A test platform is specially designed and set up. The kinetic model of test specimens (including the test joint surfaces) is derived. The experimental system is developed. The tangential dynamic contact stiffness and contact damping are identified by the experimental system. The variation rules of the contact stiffness and contact damping with changing of pre-load, exciting frequency and surface roughness are got and summarized. And the rules are consistent with the physical essence of joint surfaces.

In this paper, the seismic behavior of partially encased concrete columns and steel beam connection are studied, which contains 4 different structures of beam-column joints. By applying a low cycle loading, the failure modes and the strain distribution of each connected component plate domain were studied. The effect of the end plate thickness, stiffened plate, and back plate on the node bearing capacity, stiffness and ductility was analyzed. The bearing capacity of the specimen is improved with the end plate thickness increases, and a lot increased with setting the back plate.

In this paper, NiTi-Ti2Ni-TiC composite powders were first prepared by in-situ reaction in molten salt and then sintered by a cubic high pressure apparatus under 8 GPa to produce bulk composite material at a short time. It was found that the composite was composed of TiC particles embedded in NiTi-Ti2Ni matrix, in which the Ti2Ni encapsulated TiC particles. The martensitic transformation of the NiTi matrix was evidenced by differential scanning calorimetry analysis. The research on the sintering mechanism shows that there may be a reaction like TiC +Ti2Ni 􀃆 Ti2C + NiTi existing under the pressure up to 8 GPa

For evaluation indicators are dependent on each other and contradictory, difficult to conduct a comprehensive evaluation in the oil-gas production management program, the paper uses the fuzzy mathematics method to establish calculation model, selects out a best solution from a number of programs to help field managers to make the right decisions and judgments by the fuzzy comprehensive evaluation.

Design automation is always one of research focuses in the field of industry practices. With the development of computer science and technology, speech recognition technology attracts increasing researchers, and it is widely applied to industrial production. Around design automation, we propose a geometry modeling method through design intent using speech recognition, which is an automatic and efficient geometry modeling method. This paper discusses the speech recognition for design intent of geometry modeling using Hidden Markov Model, HMM. In this paper, firstly, the research framework is explained in detail; Secondly, analysis on the related theory and technology about the speech recognition are conducted, including speech signal collection, technology of data processing, technology of training and recognition of model, etc.; Thirdly, some experiments are carried out to validate above discussions; Finally, recognition efficiency comparisons between HMM and DTW are discussed. Experiments show that using HMM for the speech recognition of design intent is feasible and reasonable.