• Structural Engineering and Mechanics
• /
• v.84 no.5
• /
• pp.699-706
• /
• 2022

Settlement control techniques are critical for the safety of shield tunnel constructions, especially for facing complex situations. In this study, the shield tunnel structure from Huaita east road station to Heping Road station in Xuzhou metro No.3 line (China) is taken as engineering background, which has various complex problems of the upper-soft and lower-hard composite stratum conditions, twin curve shield tunnels, and underpass the foundation of the piled raft. The deformation characteristics of shield tunnelling passing through buildings are explored. Subsequently, comprehensive research methods of numerical simulation and field measurement are adopted to analyzing the effectiveness of settlement control by using the top grouting technique. The results show that the settlement of the buildings has obvious spatial characteristics, and the hysteresis effect can be obviously observed in soil deformation caused by shield construction. Meanwhile, the two shield constructions can cause repeated disturbances, reducing the soil deformation's hysteresis effect. Moreover, the shield tunnel's differential settlement is too large when a single line passes through, and the shield construction of the outer curve can cause more significant disturbance in the tunnel than the inside curve. Notably, the proposed process control parameters and secondary topgrouting method can effectively control the deformation of the shield tunnel, especially for the long-term deformation.

• The Journal of the Convergence on Culture Technology
• /
• v.8 no.6
• /
• pp.757-763
• /
• 2022

In the NATM tunnel construction method for urban subway and underpass construction, various causes of disaster exist. In this study, in order to analyze the importance of disaster influencing factors during NATM tunnel excavation, the possible risk factors were analyzed through prior research such as drilling, charging and blasting, It was divided into the work items of wrinkle treatment, pumice cleanup, and support materials. Next, the final 21 detailed measurement indicators were selected through the FGI survey of related experts, and AHP (Analytic Hierarchy Process) analysis were conducted. As a result, it was found that the workers involved in the tunnel construction were the most influential disaster influencing factor.

• Geomechanics and Engineering
• /
• v.35 no.4
• /
• pp.395-409
• /
• 2023

Long-span suspension bridges have tunnel anchor systems to maintain stable cables. More investigations are required to determine how closely tunnel excavation beneath the tunnel anchor impacts the stability of the tunnel anchor. In order to investigate the impact of the adjacent tunnel's excavation on the stability of the tunnel anchor, a large-span suspension bridge tunnel anchor is utilised as an example in a three-dimensional numerical simulation approach. In order to explore the deformation control mechanism, orthogonal tests are employed to pinpoint the major impacting elements. The construction of an advanced pipe shed, strengthening the primary support. Moreover, according to the findings the grouting reinforcement of the surrounding rock, have a significant control effect on the settlement of the tunnel vault and plug body. However, reducing the lag distance of the secondary lining does not have such big influence. The greatest way to control tunnel vault settling is to use the grout reinforcement, which increases the bearing capacity and strength of the surrounding rock. This greatly minimizes the size of the tunnel excavation disturbance area. Advanced pipe shed can not only increase the surrounding rock's bearing capacity at the pipe shed, but can also prevent the tunnel vault from connecting with the disturbance area at the bottom of the anchorage tunnel, reduce the range of shear failure area outside the anchorage tunnel, and have the best impact on the plug body's settlement control.

• Journal of Korean Society for Geospatial Information Science
• /
• v.22 no.4
• /
• pp.63-69
• /
• 2014

Due to population growth and urban development in construction technology has expanded living space, underground construction as public transport as has been extended to the ground and underground urban traffic congestion increases. This underpass Stations sphere of influence this development was the center of the living space, space-time became a cultural space. However underpass ground space and time and space are enormous difficulties in contrast visibility due to smoke when light levels are low fire occurs, momentary loss of judgment errors due to a sense of orientation, rapid diffusion and ambient oxygen deficiency due to acquisition limitations, such as the Open resulting in property damage and personal injury. The purpose of this study is to analyze the existing system with respect to the address of the underground shopping center and system for presenting an address to the underground shopping mall in the basement of the straight and circular in connection with the street name address. Also can be known only to evacuate their citizens to address the position in the event of a fire inside the basement through the underground shopping mall address standardization system, the fire department only address exact location is being judged will be identified.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.19 no.2
• /
• pp.84-91
• /
• 2015

In this paper, to overcome disadvantages of existing lining boards, the parametric studies to evaluate safety and verify performance of newly suggested lining boards was performed. Since the calculated stresses of steel plates are lower than the allowable stress for considered all analytical variables, end reinforcement locations, and crane rail loads, it can be concluded that the suggested lining board is structurally safe. Where, "$3,000{\times}2,000{\times}6t$" was select to be optimized cross-section and the reinforcement from the end to 200mm to the internal direction looks like the best case. In addition, the suggested lining board is economical since the steel amount per unit area compared to existing lining board is reduced by 36% and it can apply to the lining structural system of subway and underpass since construction speed is past due to the less installation number of lining boards.

• Journal of the Society of Disaster Information
• /
• v.16 no.4
• /
• pp.734-746
• /
• 2020

Purpose: Increase in the size and number of underpasses rises occurrence of disasters such as fire and flooding inundation in underpasses. In the occurrence of disasters, the underpasses are more vulnerable to expose of crucial disasters than the general roads due to they are built underground. Therefore, The purpose of this paper is to derive system improvement items to prevent and control disasters in underpasses. Method: A hierarchical model of disaster impact factors and alternatives was developed based on prior researches and expert advices on disaster analyses and impact factors in the underpasses. The developed model was employed for surveys of pairwise comparison, and rankings of improvement were determined by applying the AHP method. Result: With a consistency of the surveys, results of relative weights of evaluation criteria(traffic accidents, fire, flooding inundation) and alternatives(law, system/planning, maintenance/human factor/environment) shows that improvement of laws and system related to the fire disaster is a top priority to prevent and control disaster of the underpasses. Conclusion: From experts' point of view, strengthening laws and systems related to disater prevention facilities such as water spray facilities, external(ground) exit in relation to fire in underpasses showed that it is an alternative to prevent disasters and minimize damage to underpasses.

• Korean Journal of Environment and Ecology
• /
• v.20 no.3
• /
• pp.340-344
• /
• 2006

The objective of this paper was to investigate the potential of road-crossing structures as biological corridors that can overcome wildlife habitat fragmentation caused by road construction. Snow tracking on animal trace adjacent to and under bridges, underpasses, and culverts of eight rural highways in Korea was carried out. A total 89 structures were monitored and the results follow. First, the probability of road crossing increases with the increasing cross sectional size of crossing structures. Second, small to medium sized carnivores such as raccoon dog, leopard cat, and Siberian weasel use all types of structures. Finally, water deer, or large herbivore crossed only under bridges. Consequently, further studies are necessary to identify suitable types of road crossing structures that can mitigate the probability of road-kills and habitat fragmentation of water deer.