East Station Research Articles

Regional subsidence monitoring and prediction along high-speed railways based on PS-InSAR and LSTM

The rapid construction of high-speed railways in China has forced more and more routes to pass through slow subsidence zones caused by groundwater extraction or underground mining. It is crucial to carry out deformation monitoring and prediction those areas along high-speed railways to ensure the safe operation. Twenty-nine periods of Sentinel-1A data between Taiyuan South Station and Taigu East Station were first processed using the PS-InSAR technique, and the ground subsidence sequences at ten typical points were selected. Then the Variational modal decomposition (VMD) was combined with the Adaptive Boosting Algorithm (AdaBoost), and the VMD-LSTMAda-LSTMAda model was constructed by combining the long short-term memory (LSTM) model for the prediction of regional ground subsidence along the high-speed railway. The results show that the cumulative subsidence within the 200 m buffer of the line centreline is − 37.58 − 89.19 mm, and the annual average subsidence rate is − 26.57 − 82.63 mm/y. The proposed model can reduce the complexity of the deformation sequence and combines with AdaBoost to improve the prediction accuracy of the LSTM model. It performs well in terms of RMSE, MAE, MAPE, and R2 at the two feature points (3703: RMSE = 0.82 mm, MAE = 0.25 mm, MAPE = 6.31%, and R2 = 0.94; 522: RMSE = 1.32 mm, MAE = 0.46 mm, MAPE = 4.92%, R2 = 0.95). The model improves the accuracy of regional subsidence prediction along the high-speed railway.

Multimodal Hong Kong: Perceiving pedestrian footbridge spaces in a high-density area through soundscape and smellscape perspectives

In prior research on Hong Kong's acoustic environment, noise has been the primary focus, highlighting its diverse sources and its detrimental impact on physical and mental health. However, there is still limited exploration of multi-sensory perspectives in Hong Kong. Mong Kok is one of the world's most densely populated areas, with a density of 130,000 people per square kilometre. Amid the bustling urban life, interactions and activities of residents, tourists, and vendors contribute to the complex soundscape. The area offers a diverse array of markets, street food, and intense aromas, creating a dynamic smellscape. This study focuses on the Mong Kok East pedestrian footbridge (connecting Mong Kok East Station to Nathan Road, approximately 400 metres), selecting six locations on and beneath the footbridge. During the on-site sensory walk experiment (n=30), we recorded ambient sounds and reproduced the soundscape in the laboratory to compare experiences stemming from various sensory modes. The sensory walk includes evaluating soundscape, smellscape, and an overall assessment. Participant feedback helps highlight what they are most concerned about, and the usage patterns and preferences of the six locations reflect the desired soundscape and smellscape, guiding recommendations for sensory design in high-density spaces.

Research on intelligent identification and resource utilization of TBM muck in breezy granite strata

Tunnel boring machines (TBMs) excavating breezed granite strata produce a lot of muck, including rock powder and gravel. To promote waste recycling and environmentally friendly muck utilization, a series of studies was conducted on the intercity railway section from ShenZhen Airport East Station to HuangMaBu Station in China. First, the muck image dataset was obtained using a camera, and the SAM-YOLO neural network model was adopted to intelligently identify the features of the particle size and content of the muck. Subsequently, the muck was used as an alternative material for the backfill slurry raw material, and the optimal slurry ratio was determined through laboratory tests. Finally, a new backfill slurry was applied on-site. The results demonstrated that the established SAM-YOLO model can accurately and quickly identify muck characteristics, which can be roughly classified by particle size into three categories: rock powder (0-5 mm), gravel (5-10 mm), and crushed rock (10-31.5 mm). Rock powder was utilized to make the monomortar, gravel was used for backfilling, and the crushed rock was broken again to gravel particle size to be used for backfilling. The laboratory test and field application results indicated that the new monomortar can fulfil engineering requirements after the backfilling of gravel, and the optimal water, cement, and rock powder mix ratio is 0.9:1.0:1.0. This research thus provides effective guidance for the utilization of muck in similar projects.

Study on the dynamic construction mechanics of side piles in metro station using the pile-beam-arch method

Based on the Tianhe East Station in Guangzhou Metro Line 11 engineering, this paper analyzes the formation mechanism of soil arching effect (SAE) of station by pile-beam-arch (PBA) method in the excavation process and studies the mechanics and deformation laws of side piles in different construction stages under different pile spacing conditions. The results show that the formation, development and destruction of SAE between piles are closely related to construction process. Both too large and too small pile spacings are not conducive to the development about SAE between piles; when it is located between them, the SAE between piles exerts greatly. In the form of composite lining system, supporting piles as well as SAE between piles play an effective role in supporting soil behind piles. The lateral deformation of pile body is most significant in the completion of buckle arch to the excavation of first soil layer, which is the critical construction phase to reduce lateral deformation of side pile. The axial forces of side pile increase gradually with the excavation of station, and the change is the most drastic at the excavation for first soil layer. The influence of pile spacing on vertical settlement and axial force of side piles is much greater than that of horizontal displacement and bending moment.

Evaluation of the dynamic additional impact about foundation pit construction on the existing adjacent subway station with the PBA method

In this paper, relying on the Tianhe East Station project of Guangzhou Subway Line 11, the deformation and mechanical evolution rules about the existing adjacent stations with the pile-beam-arch (PBA) method in the all excavation stages about the new foundation pit is evaluated through numerical calculation method. It was revealed that that the largest displacement about the existing station’s side wall and the middle column reaches 2.1mm and 1.5mm respectively during the excavation about the foundation pit. Due to the impact about construction of the foundation pit, the uplifting phenomenon occurs on the side of the foundation pit, and the maximum uplifting value reaches 0.4mm. When the construction about foundation pit is finished, the whole station floor shows a deformation form of “left lower torsion”, and the largest compressive stresses as well as tensile stresses about the side wall and the bottom plate do not reach the standard limiting value, and the whole is being a relative safe status. With the increase about the excavation depths, the axial forces about the middle column gradually increase to 7016kN, and the incremental axial forces about the middle column after the construction is completed accounts for about 11.7% of the axial force of initial construction. Therefore, the disturbance effect about foundation pit construction on the adjacent station with the PBA method can not be ignored. The research result in this paper may offer some important references for the construction and design of similar cases.

Analysis of the influence of side wall opening on the arch structure of metro station using the PBA method

In order to meet the traffic and commercial needs, it is sometimes necessary to open the side wall of the metro station, while the current research on the mechanical properties and safety of the arch caused by the opening of the side wall of the station by pile-beam-arch (PBA) method is rarely involved. In this paper, based on the Tianhe East Station project of Guangzhou Metro Line 11 located in soft-hard uneven stratum using PBA method, the settlement law and mechanical characteristics of the arch under different side wall opening conditions is analyzed, and the influence of opening construction and opening span on the safety of arch is also further studied. The results show that the settlement caused by the opening of the side wall is mainly concentrated in the upper part of the opening area, and gradually expands around the opening area with the increase of opening span, and the maximum settlement occurs in the middle part of the arch. Opening leads to the differential settlement at both ends of the arch. With the increase in opening span, the settlement growth trend of the right side of the arch is greater than that of the left side. The opening of the side wall leads to the increase of the safety factor of the arch body and the decrease of the safety factor of the right arch foot, while the change of the safety factor of the left arch foot is not obvious, and the safety factor meets the specification requirements.

A multi-agent simulation based train platforming research for facilitating passenger transfer in a high-speed railway station

The train platforming problem is one of the most investigated topics in the train operation field. However, a systematic understanding of how train platforming improves the convenience of passenger transfer procedures is still lacking. To face the rapidly growing transfer demands in the high-speed railway station, this paper proposes a transfer-facilitating-oriented train platforming approach based on a multi-agent train operation simulation model. By evaluating the transfer connection quality using an indicator named Transfer Connection Strength(TCS), which considers transfer distance and transfer time, the proposed transfer-facilitating-oriented train platforming strategies can establish more convenient transfer connections and so improve the transfer service. A track occupation horizon based on the modelling of accurate train running processes is utilized to detect route conflicts and guarantee conflict-free train operations in the simulation model, enabling the solutions’ feasibility of train platforming to be taken into account. A series of simulation experiments are conducted using real data of Zhengzhou East station in China. The experiment results show that, the proposed transfer-facilitating-oriented train platforming strategies are capable of obtaining a greater number of convenient transfer connections. The feasibility can be guaranteed by permitted train delays and route conflict detection for the succeeding trains in a forward-looking period. Additionally, the platform assignment plans can be generated with a specified priority of transfer distance or transfer time.

Investigation of the consistency of changes in the wavelet phase characteristics of heliocosmic and climatic variables and changes in the components of the word water balance. Part 2

The relevance of research: is due to the need to establish true causes and patterns of changes in the hydrometric characteristics of the global water balance as a whole and its components, natural media on Earth.
 Purpose of research: Establishment of patterns of mutual influences and causes of changes in the components of world water balance on Earth: settlement changes in thermal and water resources on the territory of sushi, clouds on continents, lake levels on continents, the Caspian Sea, Arctic Islands, Greenland and mountain glaciers.
 Objects: Temporary series of heliocosmic and global climatic variables constituting a global water balance.
 Methods of research: the method developed by the author of the calculation of the wavelet phase-frequency and phase-temporal characteristics of the group of the studied time series specified at equal intervals of time, with the calculation of their correlation matrices and the construction of the charts of the variables in two coordinate systems, comparative analysis.
 Results of research: It is shown that in cyclical climate change on land, global water balance as a whole and its components in different relative units and phase orientations, depending on the properties of components of water balance, natural environments, two groups of variables are studying: Helicosmic (Baricenric Sun Movements, Solar activity, long-term solar insolation, greenhouse gases, ozone concentration in the ionosphere, elements of the Earth orbit, geomagnetic field) and global temperature climatic variables caused by changes in the helikosmic factors leading from which is the barycentric movements of the Sun. There is a variability of the water balance depending on their geographic locations on continents. It is shown that the calculated changes in thermal and water resources on the territory of the sushi, changes in clouds and levels of lakes on continents at the observed time intervals is significantly interconnected in the phase-frequency domain, coordinated with changes in the heliocosmic variables leading from which is the barycentric movements of the Sun. It is shown that the change in the level of Lake Rudolf, located in Kenya, occurs in antiphase with changes in other lakes from the phase-frequency domain due to changes in the level of the lake in antiphase with changes in evaporation, evaporation and precipitation the calculated changes in thermal and water resources on land ; Such a phenomenon is observed in changes in Lake Neivasha (Kenya). Data analysis obtained at the East station in Antarctica, bottom sediments of the ocean, in 379.3-1.1 thousand years in the past, graphs of changes in the elements of the Earth orbit, established high consistency of changes in the Caspian level with changes in the angle of inclination, precession and eccentricity of the Earth orbits; In Holocene, agreed with changes in solar activity; coordinated with changes in earthquakes, the speed of rotation of the Earth and the duration of the earth's day, as well as the changes in YMO and the El-Nio phenomenon, with changes in evaporation and precipitation on land in the phase-frequency domain due to the influences of heliocosmic factors. It has been established that changes in the components of the water balance of the Arctic Islands, Greenland and the mountain glaciers are divided into two subgroups; The first includes changes in precipitation and drains, to the second, changes in the resulting and increments of balance sheets. The components of the first subgroup are strongly agreed with the changes in the helixosmic factors, the second, with changes in climatic variables with a negative sign in changes in the balances of the Arctic Islands and Greenland; The second subgroup in the balance of mountain glaciers is strongly agreed with changes in the helicosmic variables with a negative sign in the phase-frequency domain in the observed inter. In changes of phase-temporal characteristics of groups of factors are observed lattice structures of differently and unidirectional changes of variables, characterizing stochastic variability in natural environments.

First record of Cyprideis torosa (Jones, 1850) (Crustacea: Ostracoda) in the East of Al-Hammar Marshes, Southern Iraq

CyprideCyprideis torosa is recorded for the first time in east Al-Hammar marshes and it was collected from three stations (Al-Sallal, Al-Nagara and Al-Masʼhab) in east of Al-Hammar marshes between January and December 2021. The ecological parameters measured were water temperature, dissolved oxygen, pH, conductivity, salinity and turbidity and were related to the presence or absence of the species in question. is torosa is recorded for the first time in east Al-Hammar marshes and it was collected from three stations (Al-Sallal, Al-Nagara and Al-Masʼhab) in east of Al-Hammar marshes between January and December 2021. The ecological parameters measured were water temperature, dissolved oxygen, pH, conductivity, salinity and turbidity and were related to the presence or absence of the species in question.

Case Study of an Underpinning Pile Foundation for an Interval Tunnel Crossing an Existing Bridge

When urban subway tunnels cross existing bridge pile foundations, having a pile foundation underpinning that ensures the safe operation of existing bridges while enabling the safe construction of subway tunnels is the focus of attention. This paper takes the running tunnel project from Huaguoyuan West Station to Huaguoyuan East Station of Rail Transit Line 3 in Guiyang City, Guizhou Province as the background. The reasonableness and feasibility of the passive underpinning construction scheme for the Guihuang Viaduct was studied. The construction plan includes the following steps: underpinning pile construction, foundation pit excavation, the concreting of the underpinning bearing platform, and existing pile truncation. In order to ensure the structural safety of the existing viaduct during the construction of the pile foundation underpinning, a 3D numerical model of the construction of pile foundation underpinning and the whole process of tunnel construction was established. The settlement calculation results of the foundation pit and bridge pier were compared and analyzed with the field monitoring data to verify the accuracy of the numerical model. Further detailed analysis of the settlement of the bridge deck, the deformation of the existing piles, the axial forces of the existing piles, and the forces on the underpinning bearing platform was carried out. The results show that the bridge superstructure load can be transferred to the underpinning bearing platform smoothly after the existing pile truncation construction. The removal of obstacle piles during tunnel excavation has a very limited impact on the superstructure of the bridge, proving the reasonableness and feasibility of the construction plan.

An Integrated Intelligent Approach for Monitoring and Management of a Deep Foundation Pit in a Subway Station.

As the scale of foundation pit projects of subway stations in Shenzhen becomes larger, and the construction constraints become more and more complex, there is an urgent need for intelligent monitoring and safety management of foundation pits. In this study, an integrated intelligent approach for monitoring and management of a deep foundation pit in a subway station was proposed and a case study based on the Waterlands Resort East Station Project of Shenzhen Metro Line 12 was used for validation. The present study first proposed the path of intelligent foundation pit engineering. Based on geotechnical survey and building information modeling, a three-dimensional transparent geological model of foundation pit was constructed. Multi-source sensing technologies were integrated, including micro electromechanical system sensing technology, Brillouin optical frequency domain analysis sensing technology, an unmanned aerial vehicle and machine vision for real-time high-precision wireless monitoring of the foundation pit. Moreover, machine learning models were developed for predicting key parameters of foundation pits. Finally, a digital twin integrated platform was developed for the management of the subway foundation pit in both construction and maintenance phases. This typical case study is expected to improve the construction, maintenance and management level of foundation pits in subway stations.

Spatial and temporal variation of bacterial population in ambient air particulate matters (PM2.5, PM10 and TSP) of Isfahan city, Iran

Introduction: Airborne particles are considered as an important indicator of outdoor air quality. Many health problems have been linked to high concentrations of Particulate Matters (PMs) and their associated microorganisms. The aim of this study, therefore, was to investigate the population of bacteria in PMs in various times and locations.
 Materials and methods: The PM samples including PM2.5, PM10 and Total Suspended Particles (TSP) were taken from 4 different stations of Isfahan city, Iran on February (cold season) and July (warm season), 2019 using an air sampling pump on culture media. The number of bacterial colonies was counted after 48 h growth in the incubator at 37 oC. The PMs concentration and some morphological characteristics of bacteria were also investigated.
 Results: The highest number of bacterial colonies was in TSP followed by PM10 and PM2.5. The bacterial populations at two stations in north and east. of the region in the warm season were higher than in the cold season, and the respective situation in the other two stations at south and center of the city was reversed, which seems somehow to have been the result of the PMs concentration of difference of pollution sources in various locations and seasons.
 Conclusion: This study highlights the importance of PMs pollution especially PM2.5 (i.e. the main factor affecting the air quality of the study area) as the carrier of microbial pollution in the air which could adversely affect human health.

A Genetic Simulated Annealing Algorithm for Real-Time Track Reallocation in Busy Complex Railway Station

Track failure at a railway station is a common disruption in the station area caused by abnormal weather or frequent use. This paper focuses on the real-time track reallocation problem to recover the affected track utilization plan and minimize the total train delays and passenger inconveniences. Train platforming operations in busy complex passenger stations are generally conducted according to fixed track utilization rules. In this paper, we presented a mixed-integer linear programming model for train platforming problems with constraints relevant to fixed track utilization rule and objectives of balanced usage of tracks. Furthermore, we proposed an improved genetic simulated annealing algorithm based on improved crossover and selection methods without breaking the fixed track utilization rule constraint. An experiment of Guanzhou East Station with fixed track utilization rules shows the effectiveness of the proposed model and algorithm. The model and algorithm provide efficient approaches for track reallocation problems based on fixed track utilization rules in busy complex passenger stations.

Comparative Study on Characteristics of Urban Road Network in Station Catchment Area between China and Other Countries for Station-City Integration

The urban road network is one of the most important factors affecting urban traffic operation in station catchment areas, as well as the main factor in station-city integration. China’s high-speed railway has developed rapidly, and station catchment areas encompassed by station-city integration have emerged as city planning and urban design aims. However, the differences in urban road network characteristics in the station catchment area between China and other countries have not been adequately researched yet. Considering 20 station catchment areas encompassed by the station-city integration as examples, this study analyzes the intersection quantity and network density in station catchment areas to compare the characteristics of urban road networks in China with those in Europe, North America, and Japan. Combined with the square block model calculation, we found the following. (1) The network density in non-China cases is concentrated in 16–22 km/km2. The Honkong West Kowloon Station and Shapingba Station approach this range, while the Shanghai Hongqiao Station and Hangzhou East Station feature considerably lower values than this range. (2) The intersection quantity in non-China cases is concentrated in 225 pcs/km2. Except for that of the Honkong West Kowloon Station, the values for the Shapingba Station, Shanghai Hongqiao Station, and Hangzhou West Station are lower than this range. (3) Developing small-scale blocks by gridding has an optimal effect on station catchment areas within the side-length range of 47.1–97.5 m. (4) The current situation of the entire urban road network and the specifications for the design codes of the road network exhibit a certain correlation with the road network characteristics of the station catchment areas.

Robustness-Oriented Optimization of Train Platforming Problem in Busy Complex Railway Station

In this paper, we present a track-circuits-based model for robust train platforming problem (RTPP) at busy complex stations. First, we explicitly explained the operation process of different train types and fixed track utilization rule. Second, we propose a multicriterion scheduling model for RTPP with objectives of minimizing the weighted number of delayed trains, minimizing trains that break rules, and maximizing robustness based on sectional-release interlocking system. Third, we design a hybrid heuristic algorithm to solve the above model based on dispatching rules and present different new solution generation strategies to further optimize rule-based solutions. Performance of the new solution generation strategies and algorithm is evaluated based on a case study for Guangzhou East Station. To validate the effectiveness of robustness indicator, we compared its performance on delay propagation counteraction with a TPP model without robustness objective under the same perturbation scenario.

Analysis of Past and Projected Trends of Rainfall and Temperature Parameters in Eastern and Western Hararghe Zones, Ethiopia

Smallholder farmers in East and West Hararghe zones, Ethiopia frequently face problems of climate extremes. Knowledge of past and projected climate change and variability at local and regional scales can help develop adaptation measures. A study was therefore conducted to investigate the spatio-temporal dynamics of rainfall and temperature in the past (1988–2017) and projected periods of 2030 and 2050 under two Representative Concentration Pathways (RCP4.5 and RCP8.5) at selected stations in East and West Hararghe zones, Ethiopia. To detect the trends and magnitude of change Mann–Kendall test and Sen’s slope estimator were employed, respectively. The result of the study indicated that for the last three decades annual and seasonal and monthly rainfall showed high variability but the changes are not statistically significant. On the other hand, the minimum temperature of the ‘Belg’ season showed a significant (p < 0.05) increment. The mean annual minimum temperature is projected to increase by 0.34 °C and 2.52 °C for 2030, and 0.41 °C and 4.15 °C for 2050 under RCP4.5 and RCP8.5, respectively. Additionally, the mean maximum temperature is projected to change by −0.02 °C and 1.14 °C for 2030, and 0.54 °C and 1.87 °C for 2050 under RCP4.5 and RCP 8.5, respectively. Annual rainfall amount is also projected to increase by 2.5% and 29% for 2030, and 12% and 32% for 2050 under RCP4.5 and RCP 8.5, respectively. Hence, it is concluded that there was an increasing trend in the Belg season minimum temperature. A significant increasing trend in rainfall and temperature are projected compared to the baseline period for most of the districts studied. This implies a need to design climate-smart crop and livestock production strategies, as well as an early warning system to counter the drastic effects of climate change and variability on agricultural production and farmers’ livelihood in the region.

Keanekaragaman Dan Dominansi Pohon Penyusun Hutan Lindung Di Pulau Marsegu Kabupaten Seram Bagian Barat

Maluku is known as an archipelago and has high biodiversity. One of the many islands in Maluku that has biological natural resources is Marsegu Island in the West Seram district. Marsegu Island has a very high diversity of marine resources, various types of birds and various vegetation diversity of trees. The diversity of trees in vegetation shows a variety of compositions, both variations in shape, structure or morphology, color, number, and other characteristics of plants in an area. Tree vegetation is the main constituent of forest areas and has an important function in water management, germplasm reserves, life support, development resources and sources of foreign exchange. This study aims to determine the diversity and dominance of protected forest trees on Marsegu Island, West Seram district. The method used in this research is the belt transect method. Furthermore, the tree species were identified based on the identification book. Data were analyzed using the diversity index formula from Shannon-Wienner and Simpson dominance index. The results of research conducted in the eastern and western parts of Marsegu Island found 22 species of trees as the protected forest on Marsegu Island. The Diversity Index at both stations is in the medium category with the results obtained that the east station is 2.2652 while the west station is 2.3761 and is in a stable condition, while the Dominance Index at both stations is low with the results obtained that the eastern station is 0.1618 while the west 0.1135 and no species dominates.

Optimization Principle and Application of Excavation Method for Large Section Metro Station

Developing countries are still in the stage of infrastructure construction. For the reasons of design and economy, it is inevitable to encounter large section tunnel when building subway and expressway in urban construction. Taking the tunnel project of Central Park East Station of Chongqing Metro Line 10 as the case background, the cross-section optimization and process optimization of each section in the construction of extra-large cross-section tunnel are studied. Based on the principle of analogy analysis, the optimization model of the super-large section tunnel is constructed from five aspects: horizontal stratification optimization, horizontal block optimization, plane partition optimization, longitudinal section optimization and three-dimensional block optimization. Finally, a better excavation scheme than the original design is obtained by using the plane optimization model. Therefore, it can be used as a reference for similar projects to optimize tunnel construction methods.

Analysis of design points of water supply, drainage and fire extinguishing system of Taihe East Station on Shanghe Railway

As the most representative building along the railway, the high-speed railway station has become the key project of each line. The water supply, drainage and fire extinguishing systems are important parts of railway stations, including such functional contents as production and living water supply, sewage and wastewater, rainwater, fire protection of station houses, platforms, exit channels, drop-off platforms, parking yards, auxiliary houses, etc. Taking Taihe East Station as an example, this paper introduces the content of the water supply, drainage and fire extinguishing system of the high-speed railway station and analyzes the design points to provide a case reference in this aspect.

Optimization of sequential excavation method for large-section urban subway tunnel: A case study

In response to the requirement for population increase, the cross-section area of the urban subway is enlarged, resulting in that one-time excavation technology cannot be directly applied to the excavation of large-section tunnels. Consequently, how to partition the cross-section of the large-section tunnels and optimize the corresponding construction parameters is of great significance. In this paper, we establish a unified planar partition optimization model based on the four parameters of the number of horizontal layers, the number of transverse partitions, the height of the step, and the width of sections. Moreover, using the dynamic programming principle, we can further obtain the optimal excavation sequence and the construction parameters of the large-section tunnels by solving the planar partition optimization model. Combined with the case of an extra-large cross-section tunnel excavation of Chongqing Metro Central Park East Station, the paper optimizes the excavation method of the tunnel with the aim of the maximum construction efficiency and tunnel stability to obtain the optimal excavation sequence, the optimal construction parameters, and the optimal comprehensive evaluation index. The practice has proved that the optimization model based on the dynamic programming principle can effectively solve the problem of large-section tunnel construction. The case analysis can provide an effective reference for similar large-section tunnel projects.