The excavation adjacent to an existing subway station is a high-risk project during the underground engineering, which has an inevitable impact on the subway structure to affect the safety of train operation. This Paper studies the excavations adjacent to a subway station on its both sides. A 3D numerical simulation with finite element code MIDAS GTS/NX is conducted to analyze the proposed excavations' impact on the subway station as well as the accessory structure. The deformation law and the corresponding technical measures to contain the deformation of station structure are proposed afterwards, which could be a guideline for the design and construction of similar projects.

The box culvert structure is an important part of the internal structure of the tunnel. The stability of the box culvert structure directly affects the safety of the tunnel structure, so it is particularly important for the deformation analysis of the box culvert structure. This study uses the finite element software ABAQUS to establish a numerical model of soil-tunnel-assembled box culvert, and quantitatively analyzes the influence of different construction loads on the deformation of the box culvert structure. Through analysis and summary, the horizontal and vertical deformation of the box culvert structure under construction load and the force deformation performance of the junction of the box culvert structure are obtained. At the same time, the deformation performance of the connection between the internal prefabricated box culvert and the side plate under the load of the construction vehicle is also obtained. It has certain guiding significance for the research on the force of the box culvert structure inside the tunnel.

In recent years, prefabricated buildings have developed rapidly because of their high efficiency and time saving, but the large consumption of resources has also led to many environmental problems. In order to explore the impact of prefabricated buildings on the environment, the environmental impact assessment of the prefabricated buildings based on Life Cycle Assessment Theory (LCA) and Willingness to Pay Theory (WTP) was carried out. First of all, this article combines field research and literature research, using BIM modeling methods to obtain the engineering quantity of prefabricated and cast-in-place buildings. Secondly, analyzing the whole process of the two construction modes based on the life cycle theory, calculate and obtain the consumption list. Next, the ReCiPe method is used to evaluate the environmental impact of prefabricated buildings, and five types of midpoint environmental impact assessment results are obtained: greenhouse gas emissions, fine particulate matter generation, acid gas emissions, energy and mineral resource consumption, etc. Finally, based on the theory of WTP, all kinds of environmental effects are unified for comparative analysis. The results show that the environmental load of the prefabricated construction method is greater than that of the cast-in-place method. It is necessary to further improve the standardization in the production technology and management methods to obtain more advantageous environmental performance.

As our country urbanization and economic development accelerating, traffic problems become increasingly serious. In urban road network, the intersection delay has a major influence on road impedance even the choice of the path. In order to reflect the actual situation of traffic flow distribution more accurately, the transportation network assignment model was established based on the intersection flow of delays and traffic control. By comparing delay models of signal control and analyzing the intersection impedance, the intersection optimization model was built based on delay, queuing and traffic capacity. Then, we analyzed the structure of the road network topology and traffic assignment models, researched the advantages and disadvantages of the allocation algorithm in detail. Finally, the balanced allocation algorithm for FW algorithm convergence slowly was improved. The feasibility of the algorithm was verified by examples.

The occurrence regularity and propagation mechanism of seismic activity are complicated and variable to be described by existing models. This paper presents a multifractal analysis of the Alpine–Himalayan seismic zone in time–space series. The multifractal spectrum of energy released from the seismic zone is obtained from different angles. Results show that earthquakes in the seismic zone possess complex multifractal characteristics in time–space series. Moreover, the clustering feature of the seismic activity intensity in the seismic zone is similar among the time–space series.

In order to further understand and grasp the impact of load on the vibration and noise characteristics of the transformer, this article analyzes the impact of load factors, power factor, harmonic current, three-phase unbalance and other load factors on transformer vibration and noise from the perspective of transformer vibration mechanism. A 10kV/200kVA three-phase oil-immersed distribution transformer was used as the object. Experiments were conducted to study the changes in the spectrum distribution, noise intensity and A-weighted sound pressure level of the transformer vibration and noise under the influence of different load factors. The results show that: when the frequency increases, the amplitude of the 100Hz fundamental frequency in the vibration noise signal increases, and the noise level increases accordingly; when the power factor increases, the amplitude of the odd frequency components in the vibration noise signal gradually decreases with the increase of the power factor. There is no obvious fluctuation in amplitude except 100Hz. When the harmonic current and the three-phase are unbalanced, the spectral components become complicated and accompanied by a large number of odd-order frequency multiplication components. With the increase of harmonic content, the amplitude of vibration noise signal and A-weighted sound pressure level increase significantly; the degree of unbalance and the occurrence of unbalance have a greater impact on the amplitude of vibration noise signal and A-weighted sound pressure level. The research in this paper provides a reference for the noise suppression of power equipment and the fault diagnosis technology based on vibration and noise signals.