The problem of large deformation is very prominent in deep-buried tunnel excavation soft rock, which brings serious potential safety hazards and economic losses to projects. Knowledge the stress field distribution law key ensuring rational design safe construction tunnels rock. As described this paper, theoretical analysis, numerical simulation monitoring were employed investigate surrounding rock displacement state Dongsong hydropower station Sichuan Province, China. results show that...

This study proposes an innovative methodology for accurate vehicle maneuver analysis using time-differenced GNSS carrier-phase (TDCP) measurements from smartphones, combined with a motion estimation approach based on factor-graph optimization (FGO). By leveraging the centimeterlevel precision of TDCP, method achieves displacement measurements, while FGO framework enhances speed, acceleration, pitch and heading angles, as well angular velocity. Extensive experiments involving multiple...

The problem of large deformation is very prominent in deep-buried tunnel excavation soft rock, which brings serious potential safety hazards and economic losses to projects. knowledge law support measures the key ensure rational design safe construction a rock. This paper describes rock physical mechanical tests field monitoring employed investigate cause development process Dongsong hydropower station Sichuan Province, China. results show that free expansion rate sample 20.0%, average...

Predicting and estimating the response of subway tunnel to adjacent excavation foundation pit is a research focus in field underground engineering. Based on principle two-stage method incremental method, an analytic approach suggested this paper solve problem accurate rapid way, upheavals due are solved by method. Besides, presented used practical engineering case Shenzhen Metro Line 11 verified numerical simulation situ measurement. Finally, parametric analysis performed investigate...

As an important part of road transportation, bridge engineering plays a pivotal role in infrastructure construction. The wind field characteristics the site area have essential influence on both construction and operation period bridge, especially mountainous canyon terrain. In this paper, numerical simulation using computational fluid dynamics software was conducted to examine intricate regions. study focused ideal V-shaped U-shaped canyons, aiming investigate various parameters. These...

The surrounding rock and high water pressure in weak watery strata have adverse effects on the mechanical properties of tunnel support structures. In order to optimize anti-drainage design tunnels evaluate their structural safety, this paper relies Taidacun Tunnel China–Laos Railway carry out field monitoring research. A dual-field fluid–solid coupling calculation model is established tunnel’s waterproof drainage design, combined with a bending moment curvature safety. main conclusions are...

Abstract Global navigation satellite system (GNSS) positioning performance in the urban dense environment experiences significant deterioration due to frequent non-line-of-sight (NLOS) and multipath errors. An accurate weighting scheme is critical for positioning, especially environment. Traditional methods determining weights of observations typically rely on carrier-to-noise density ratio (C/N0) elevations from satellites receivers. Nevertheless, these degraded settings, as C/N0 elevation...

The stability of ground surface along tunnels in karst terrain is influenced by complex factors, among which the features are significant ones. Under influence karst, very easy to collapse, thus causing great casualties and economic losses. To provide guidance for maintaining tunnels, an analysis system proposed assessing based on improved fuzzy comprehensive evaluation. Based case collapse review related researches, evaluation index assessment was established. ridge‐shaped membership...

Symmetrical excavation of a foundation pit inevitably causes stress redistribution and deformation in adjacent tunnels, even threatening the safety their operation. Therefore, it is practical significance to evaluate characteristics tunnels propose corresponding reinforcement measures after pit. This study, based on overlapping tunnel project section between Nanshan Station Qianhaiwan Shenzhen Metro Line 11, analyzes influence by numerical simulation method. The at different locations caused...

Underground engineering construction is facing increasingly complex geological conditions and challenges, such as surrounding rock deformation lining cracking, that seriously threaten the safety of tunnel operation. Aiming at these problems, a pipeline crossing jointed expansive mudstone strata was taken an example, disaster characteristics were analyzed through field investigation. The disaster-causing mechanism corresponding control measures studied laboratory tests numerical simulations,...

Conformal mapping has achieved many successes in engineering. It can help to solve some complex fluid flow problems. This study proposed a numerical method for conformal of closed box girder bridges and applied it flutter performance prediction, which is crucial ensuring the safety sustainability bridge structures. The characteristics coefficients were investigated. Thereafter, through searching was presented. results show that smaller error existing research. six practical agrees well with...

Global Navigation Satellite System (GNSS) positioning performance in challenging environments such as urban canyon or indoor suffer significant degradations, where frequent none-line-of-sight (NLOS) signals and multipath significantly lower the GNSS accuracy. Consequently, mitigation of NLOS effects is important to achieve accurate results. To mitigate from signals, classification signal types required. Recently, reception classifiers based on deep learning models are drawing more attention...

In rugged mountain areas, the lateral aerodynamic force and lift caused by strong winds are main reasons for overturning of trains destruction buildings structures along railroad line. Therefore, it is important to build a wind alarm system line, reasonable accurate short-time forecast basis it. this research, two methods constructive function time-series decomposition proposed pre-process input speed periodic in mountainous areas. Then, improved Auto-Regressive Integrated Moving Average...

A geostress field continuously evolves with long-term tectonic activity. fault, as a general product of movements, has great influence on the in vicinity. To analyze characteristics and influencing factors near fault fracture zone high-altitude areas, this study takes Dianda-Piru Qinghai–Tibet Plateau its research object. Based geological conditions situ stress measurement data area, refined numerical model was established using simulation to invert vicinity zone, quantitative analysis...

The construction of intersection tunnels in urban induces multiple stress redistribution the surrounding rock, leading to engineering disasters such as instability rock strata during excavation, disturbance supporting structures existing tunnels, and subsidence ground adjacent buildings. Employing an appropriate method is crucial circumventing excessive concentrations large-scale subsidence, making it a key aspect tunnel engineering. In this paper, numerical model for developed based on...

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The construction of city intersection tunnels cause multiple redistribution surrounding rock stress, resulting in the engineering disasters such as instability existing and collapses ground buildings. To mitigate formation disturbances effectively, Center Cross Diagram (CRD) method is employed tunnel construction. In this study, a numerical model for developed based on an underground circular roads project Chongqing, China, to analyze safety structure stability buildings under CRD method....

This paper is a contribution to analyzing the aerodynamic forces on streamlined box girder (SBG) with coupled vibration in potential flow. The key enabling step was assume that normal velocity of airflow at an arbitrary point surface SBG equal motion. drag force, lift and pitching moment were expressed as functions motion state SBG’s shape-related parameters. To investigate applicability this force model, analytical solution various angles attack compared numerical simulation viscous results...

All inorganic perovskite ABX₃(X=Cl, Br, I) is widely used in the research of laser devices due to its excellent optical properties, such as high luminescence quantum yield, large gain coefficient, carrier mobility and adjustable wavelength, etc. Compared with traditional edge-emitting lasers, vertical cavity surface emitting (VCSEL) has great advantages beam quality, fiber coupling efficiency, single longitudinal mode reflectivity. In this experiment, all-inorganic material...

Halide perovskite (ABX3) has become an exciting material for research in next-generation optoelectronic devices because of their remarkable photoelectric properties high stability, luminescent quantum yield and carrier mobility. However, the presence different halogen elements could have a significant impact on optical physical properties. That's they huge differences environmental exchange migration characteristics. In this work, samples with three anions CsPbBr₃,...

All-inorganic halide perovskite, such as CsPbX₃(X=Cl, Br, I) has excellent photoelectric performance, with high fluorescence quantum yield, large carrier mobility, nanocrystalline size adjustment, gain coefficient and other advantages. It broad application prospects in light-emitting diodes (LED), solar cells, lasers devices. However, the further study of perovskite materials, it is shown that way optimization process to enhance green light efficiency complex, which greatly...

As the length of tunnel continues to increase, it will be common for a single fan undertake ventilation two or more faces. However, construction multiple faces in lead complex environment tunnel, mutual interference ventilation, and difficulty discharging pollutants. Based on simultaneous this study analyzed transport law The diffusion laws carbon monoxide dust multiple-face tunnels under different working conditions were obtained by numerical simulation. It was found that when both sides...