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In the article, under field conditions (on the lane of a city road for public transport), using modeling and traffic flow analysis methods, the formation of ruts on an asphalt concrete pavement is studied. The maximum total rut depth on the road section under consideration reaches 110 mm. 715 buses and 25 trucks pass along a separate lane of the road per day, the relative rutting impact of which is from 5.68 to 16.41 compared to the design vehicle. The design of the road pavement on the experimental section with a total thickness of 48 cm is too weak for the actual traffic flow, which was the main reason for the premature failure of the road due to unacceptable rut sizes on the asphalt concrete pavement.

The advantages of the Gatling gun, such as high firing rate, large interception range, and wide range of use, have made it an indispensable weapon system in the defense field. At present, the analysis of shooting vibration of the Gatling gun is a challenging key point in related research. In response to the lack of research on the shooting vibration characteristics of Gatling gun weapon systems, this paper carries out a numerical simulation study of the launch dynamic characteristics of the Gatling gun based on the nonlinear launch dynamics theory of artillery. The results of muzzle disturbance under continuous shooting conditions are obtained, and the shooting density of Gatling guns under different situations is analyzed and compared based on the method of shooting density calculation. This research fills the gap in the study of launch dynamics of Gatling weapons, providing design references and theoretical support for the overall design and performance verification of Gatling guns.

The crank-type vibration exciters represent innovative and promising actuators for a variety of vibratory technological equipment. Extensive research has demonstrated their potential for generating specific trajectories of the working components of various technological machines. This study builds upon previous investigations of the authors, focusing on the kinematics and dynamics of crank-type vibration exciters, with a specific emphasis on analyzing the forces, moments, and torques acting on the elements of the twin crank-type actuating mechanism. The research methodology involves the development of a simplified dynamic diagram of the mechanism and derivation of the analytical expressions to describe its force parameters. Mathematical modeling and computer simulation are then conducted to analyze the forces, moments, and torques experienced by the mechanism during its motion under different operational conditions and design parameters. The results obtained provide time-dependent profiles of these parameters across various conditions and design configurations of the twin crank-type mechanism. A key scientific contribution of this paper consists in the development of the theoretical basis for creating novel techniques of dynamic and strength analysis and optimization of design and operational parameters of enhanced vibration exciters equipped with twin crank-type mechanisms. The research findings offer valuable insights for engineers involved in the development and enhancement of vibratory technological machines equipped with crank-type vibration exciters.

According to the characteristics of the soft soil subgrade in the Haiou Island section of Nansha Bridge, a comprehensive geological survey and soil analysis were conducted. Based on the analysis results, a corresponding design scheme for the soft soil subgrade was formulated to ensure bridge safety and stability. Furthermore, various reinforcement measures such as compaction, drainage, and lightweight soil were implemented to mitigate the impact of soft soil filling on the bridge structure. To evaluate the effectiveness of our treatment method, post-construction effect testing was performed using both static pressure and vibration acceleration methods. The static pressure method provided crucial parameters related to bearing capacity and compressibility of the soft soil subgrade while vibration acceleration analysis reflected response characteristics under dynamic load conditions. By comparing and analyzing results obtained from these two methods comprehensively evaluated feasibility of our treatment approach. Finally, based on experimental study findings and data analysis outcomes, it is recommended that post-construction effect testing for Haiou Island section's soft soil subgrade should employ both static pressure method and vibration acceleration method along with targeted reinforcement measures selected specifically to minimize adverse impacts on bridge structure.

In order to improve the anti-vibration properties and bearing capacity of solidified sludge, this article takes silt soil as the research object and selects sludge solidification materials with good solidification performance. The chemical element composition of muddy soil was analyzed using an energy dispersive X-ray spectrometer (EDS). The microstructure and characteristics of muddy soil and solidifying agent were characterized by transmission electron microscopy experiments (TEM). The optimal moisture content and maximum dry density of solidified sludge were analyzed using compaction tests. The unconfined compressive strength test was used to evaluate the bearing capacity and strength variation of solidified sludge. The vibration characteristics of sludge under different testing times and frequencies was studied. The research results indicate that the solidifying agent could reduce the moisture content of muddy soil significantly, improve the anti-vibration properties and bearing capacity of muddy soil effectively, which provide relevant basis for improving the performance and anti-vibration performance of solidified sludge used for roadbed filling. This study could provide innovative reference for the vibration and performance of solidified sludge used in roadbed filling.

The purpose of the article is an experimental study of the impact of the wheelsets of a mainline diesel locomotive on the railway track on straight sections of the track. The measurements were performed on a vibration measuring device consisting of MV25 DV type sensors and an oscillation converter for a digital signal. It is proved that the indicators of dynamic characteristics comply with regulatory requirements. As a result of the conducted research, digital data was collected from the ADC and general monitoring was carried out. Measurement and signal processing are carried out using special software of a personal computer such as a “Notebook”. Vertical static load of a wheelset of a railway rolling stock unit on rails: the load of a railway rolling stock unit on rails attributed to one wheelset, taking into account the actual location of the center of gravity of the superstructure.

In densely populated cities, the increasing popularity of railways and urban rail transit interchange hubs has led to the extensive use of land resources and raised concerns about the environment, especially the inevitable noise and vibration impact. This study aims to identify the propagation patterns of roof structure vibrations in railway complexes through experimental research, with the premise of maintaining normal train operation and safety, in order to lay a foundation for developing vibration mitigation strategies and optimizing functional layout. The results found that the train-induced vibrations are strongest at track level, but decrease as they move vertically and horizontally. Vibrations from passing trains are most noticeable within a single floor slab and beams, with minimal transmission at the base of columns.

Noise control is one of the most critical technical indicators to improve the performance of intelligent audio recognition system. Based on the noise cancellation technology, a distributed low noise amplification circuit design was proposed, and the PE15-0P technology was applied to realize broadband low noise amplification. The amplifier circuit used diodes and resistors for voltage division, which effectively achieved bias saturation at the transistor and then diode structure. According to the design of low noise amplifier, the noise output characteristics were simulated and analyzed. An audio enhancement method based on noise type recognition was proposed, which can optimize noise estimation by selecting parameter combinations according to noise type, so as to improve the quality and intelligibility of noise frequency signals in various noise environments. From the aspects of hardware and algorithm design, the noise signal was comprehensively reduced, and the accuracy of audio recognition was significantly improved.