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In this paper, the mechanics equation of the dynamic compaction machine arm frame is established based on the theory of statics, the arm lifting rope force is given, the influence of the wire rope force with relative position parameters changing is also discussed. The critical factors that affect the arm lifting rope force are identified. Compared the simulation and the test results, the major forces errors are less than 8%. The correctness of the theoretical study and simulation are verified. The research results could be used for the arm wire rope type selection of the dynamic compaction.

PID control and the velocity feedback control for ABS are studied of the wheel slip rate as controlled object. Comparison on these two kinds of control methods is analyzed. It is obtained that velocity feedback control and PID control exist much similarity in some extent, according to the hardware in the loop (HIL) simulation platform. However, the velocity feedback control has more obvious advantages than PID control in terms of the adaptability to different road conditions. It can maintain stable control of system dynamically under the changed road condition, leading to the braking distance shorter.

Based on the ABS model of a single wheel system, the traditional logic threshold, PID and fuzzy control method have been used to study the control system of commercial vehicle’s ABS. As the most important task of commercial vehicle’s ABS is to prevent the two front (steering) wheels from locking, the slip ratio should be controlled strictly in the safe range. A very short time of locking may cause the failure of steering, so control method which can keep slip ratio in the secure scope accurately can help vehicle avoid the danger of runaway. Set up the model on Simulink platform. Then, use the three control methods to control the ABS. By comparing and analyzing the processes and results under the control methods, find an appropriate way that can provide the most secure and effective control. From the perspective of processes (slip ratio changes), the simulations under the three control methods show the PID control gives the best slip ratio curve. The curve is almost coinciding with the ideal slip ratio curve. The oscillation of slip ratio given by fuzzy control is the most sever. From the point of view of the results (braking distance), the braking system with PID control has the shortest braking distance while with the fuzzy control has the longest. That is not to say fuzzy control is not advanced but the actual experiences difficult to get. And with the long response time, the fuzzy control is not suitable for commercial vehicle’s ABS. As a result and with the development and decreasing cost of PID controller, it is competitive in today’s ABS market.

The research achievement of strata movement law caused by subway construction and control standards was summarized and analyzed, and point out that this research on the laws of strata movement (or deformation) caused by subway construction mainly focused on three aspects. The first was research on the ground vertical settlement laws perpendicular to the tunnel excavation direction. The second was research on the ground vertical settlement laws parallel to the tunnel excavation direction. The third was research on the ground horizontal movement regularity perpendicular to the tunnel excavation direction. Through the analysis of the current research results, it is points out the shortages existing in the research, and deeply research in the future. It may provide the theoretical basis, also for practical engineering application provides a certain technical support.

Through research of vehicle dynamic feature, analysis and research of the problem of driving wandering by user retroactions, the article put forward some test and evaluation methods of driving wandering. And the article is discussed about main reasons and solutions of driving wandering in-depth.

Bottom-business multi-story masonry structure is widely used in small and middle towns in the southward in China. In the downtown of Beichuan county which affected by Wenchuan earthquake, more than 80% of this kind of building collapsed. But the Apartment of Beichuan Telecommunication Bureau behaved well earthquake resistant capacity with a moderate damage in the earthquake. The obvious difference between this building and others is the setting of winged columns in the front longitudinal wall of the first floor. For proving the influence of these members in the structure seismic capacity, the earthquake simulation shaking table test of 2 1/5 reduced scale models were designed and carried out. The models dynamic response, acceleration, displacement and strain were measured and collected, that model with winged columns behave well was testified. And the reinforcement method of balancing stiffness and increasing ductility is put forward. The results provide a foundation for the retrofitting design of the existing houses.

A parametric FEM analysis method is introduced for the design of disc brakes. The basic process of parametric FEM modeling is summarized, the FEM model of disc brakes is established. Finally, the parametric FEM strength and stiffness analysis are conducted for the typical disc brake assembly.

Shrinkage cracking is the direct cause which leads to the deterioration of durability and integrity of concrete. In this paper, ring-test methods are used to study the early age cracking characterization of compound mineral admixtures concrete which includes steel slag, blast furnace slag and fly ash. The effect of compound admixtures on cracking characterization of concrete is discussed, restraint stress caused by concrete shrinkage and cracking age are analyzed. Through the comprehensive consideration of the free shrinkage strain, creep, restriction factors on the effect of the cracking of concrete specimens. The results show that suitable proportion mineral admixtures can be used to reduce cracking in concrete. The risk of cracking can be estimated for compound admixtures concrete, so that it will improve the durability of concrete structures.

In the past, when need to draw one model of brake parts, users have to use the CAD software and make it one step by step, which wastes a lot of time and energy because of the repetitive artificially drawing. In order to improve the efficiency of drawing the models of brake parts, the paper builds one brake parts library by using the Visual C++6.0 and doing secondary development on the CATIA. Through one example, the paper proves the feasibility of building brake parts library.

A hybrid coupling beam is developed in this study to render the reinforced concrete (RC) shear wall structure a higher seismic performance. As the first protection from earthquake, the coupling beam is able to dissipate more energy when combined in series with a metallic damper. The strength of the metallic damper is carefully selected so that the RC part of the coupling beam remains elastic, while all plasticity goes into the metallic damper. This mechanism protects the RC part from seismic damage. And the metallic damper can be quickly replaced once it is damaged. This significantly enhances the reparability of entire structure, making it possible to be immediately functioned after earthquakes. The stiffness of the hybrid coupling beam is similar as the traditional RC coupling beam, so that the dynamic characteristics are almost unchanged. In this study, one hybrid coupling beam and one traditional RC beam are experimentally examined. The seismic dissipation capability of the hybrid beam is approximately twice of the traditional beam, and the damage of the RC part of the hybrid beam is very limited.

Considering the importance of vehicle active safety system, this article designs the manageable man-machine interactive software that can help engineers to design the vehicle active safety system. Engineers can interact with the software and involve in most processes of active safety system design through the visual software. And the software can improve design efficiency, shorten the design cycle, and reduce design costs. Through the successful development of the software, the paper shows the important role VC++ plays in vehicle active safety system design and this will be instructive.

Hydraulic electromagnetic energy-regenerative shock absorber is a new kind of shock absorbers, who can perform the function of a standard shock while acting as an additional source of power. One of the core components of this new shock absorber is the valve system. And its function is to rectify the direction of the oil flow. Then the oil can flow through the hydraulic motor from one port only no matter in expansion stroke or compression stroke. The research focused on the compactness, sensitivity and energy recovery rate of two different valve systems. And the results showed that the valve system composed of check valves better matched the hydraulic electromagnetic energy-regenerative shock absorber.