• Title/Summary/Keyword: deep excavations work

Search Result 6, Processing Time 0.016 seconds

A Study on Neural Networks Forecast Model of Deep Excavation Wall Movements (인공신경망 기법을 활용한 굴착공사 흙막이 변위량 예측에 관한 연구)

  • Shin, Han-Woo;Kim, Gwang-Hee;Kim, Young-Seok
    • Journal of the Korea Institute of Building Construction
    • /
    • v.7 no.3
    • /
    • pp.131-137
    • /
    • 2007
  • To predict deep excavation wall movements is important in the urban areas considering the cost and the safety in construction. Failing to estimate deep excavation wall movements in advance causes too many problems in the projects. The purpose of this study is to propose the forecast model of deep excavation wall movements using artificial neural networks. The data of the Deep Excavation Wall Movements which were done form Long research is used of Artificial neural networks training and apply the real construction work measured data to the Artificial neural networks model. Applying the artificial neural networks to forecast the deep excavation wall movements can significantly contribute to identifying and preventing the accident in the overall construction work.

Investigation of crack growth in a brick masonry wall due to twin perpendicular excavations

  • Mukhtiar Ali Soomro;Dildar Ali Mangnejo;Naeem Mangi
    • Geomechanics and Engineering
    • /
    • v.34 no.3
    • /
    • pp.251-265
    • /
    • 2023
  • In urban construction projects, it is crucial to evaluate the impacts of excavation-induced ground movements in order to protect surrounding structures. These ground movements resulting in damages to the neighboring structures and facilities (i.e., parking basement) are of main concern for the geotechnical engineers. Even more, the danger exists if the nearby structure is an ancient or masonry brick building. The formations of cracks are indicators of structural damage caused by excavation-induced ground disturbances, which pose issues for excavation-related projects. Although the effects of deep excavations on existing brick masonry walls have been thoroughly researched, the impact of twin excavations on a brick masonry wall is rarely described in the literature. This work presents a 3D parametric analysis using an advanced hypoplastic model to investigate the responses of an existing isolated brick masonry wall to twin perpendicular excavations in dry sand. One after the other, twin perpendicular excavations are simulated. This article also looks at how varying sand relative densities (Dr = 30%, 50%, 70%, and 90%) affect the masonry wall. The cracks at the top of the wall were caused by the hogging deformation profile caused by the twin excavations. By raising the relative density from 30% to 90%, excavation-induced footing settlement is greatly minimized. The crack width at the top of the wall reduces as a result of the second excavation in very loose to loose sand (Dr = 30% and 50%). While the crack width on the top of the wall increases owing to the second excavation in medium to very dense sand (Dr = 70% and 90%).

Comparison of Displacement of the Braced Retaining Wall by Developed Elasto-Plastic Analysis (개선된 탄소성 해석을 이용한 버팀지지 흙막이벽의 거동비교)

  • Shin, Jin-Whan;Kim, Dong-Shin
    • Journal of the Korean Society of Safety
    • /
    • v.19 no.2
    • /
    • pp.112-118
    • /
    • 2004
  • Recently, when being constructed the large structures, the deep excavations have performed to utilize the underground space. As the ground excavation is deeper, the damage of the adjacent structure and the ground is frequently occurred. the Analysis of the retaining structures is necessary to safety of the excavation works. There are many methods such as elasto-plastic theory, FEM, and FDM to analyze the displacement of the retaining structure. In this thesis, GEBA-1 program by the Nakamura-Nakajawa elasto-plastic method was developed. The lateral displacement of the wall was analyzed by the developed program GEBA-1, SUNEX, and EXCAD, and compared with the measured displacement bye the Inclinometer. The monitored fields were three excavation work site in S-I, S-II, and S-III area. Excavation method of each site is braced retaining wall using H-pile. Excavation depth is 14m, 14m, and 8.2m.

Safety Evaluation of Subway Tunnel Structures According to Adjacent Excavation (인접굴착공사에 따른 지하철 터널 구조물 안전성 평가)

  • Jung-Youl Choi;Dae-Hui Ahn;Jee-Seung Chung
    • The Journal of the Convergence on Culture Technology
    • /
    • v.10 no.1
    • /
    • pp.559-563
    • /
    • 2024
  • Currently, in Korea, large-scale, deep excavations are being carried out adjacent to structures due to overcrowding in urban areas. for adjacent excavations in urban areas, it is very important to ensure the safety of earth retaining structures and underground structures. accordingly, an automated measurement system is being introduced to manage the safety of subway tunnel structures. however, the utilization of automated measurement system results is very low. existing evaluation techniques rely only on the maximum value of measured data, which can overestimate abnormal behavior. accordingly, in this study, a vast amount of automated measurement data was analyzed using the Gaussian probability density function, a technique that can quantitatively evaluate. highly reliable results were derived by applying probabilistic statistical analysis methods to a vast amount of data. therefore, in this study, the safety evaluation of subway tunnel structures due to adjacent excavation work was performed using a technique that can process a large amount of data.

A Study for Safety Management on the Basis of Lateral Displacement Rates of Anchored In-situ Walls by Collapse Case Histories (붕괴 사례를 통한 앵커지지 가설흙막이벽체의 수평변위속도에 의한 안전관리 연구)

  • Chung, Dae-Seouk;Lee, Yong-Beom
    • Journal of the Society of Disaster Information
    • /
    • v.14 no.3
    • /
    • pp.367-378
    • /
    • 2018
  • Purpose: The objective of this study is to present a reasonable safety management of the anchored in-situ wall systems constructed in the ground conditions consisting of multi-layered soils underlain by bedrocks in the urban area of Korea. Method: Field measurements collected from collapse case histories with deep excavations were analyzed for the safety management of the wall systems supported by the earth anchors in terms of lateral displacement rates. Results: The average maximum lateral displacement rate in a collapsed zone of the in-situ wall significantly increased upon the completion of the excavation. Particularly, the collapse of the in-situ wall system due to the sliding occurring along the discontinuities of the rock produced a considerably large lateral displacement rate over a relatively short period. Conclusion: For predicting and preventing the collapse of the wall system during or after the excavation work, the utilization of the safety management criteria of the in-situ wall system by the lateral displacement rate was found to be much more reasonable in judging the safety of earthworks than the application of the quantitative management criteria which have been commonly used in the excavation sites.

Displacement Comparison of a Braced Retaining Wall by Elasto-Plastic Analysis Program (탄소성 해석프로그램에 의한 버팀지지 흙막이벽의 변위 비교)

  • 신방웅;김상수;오세욱;김동신
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2000.03b
    • /
    • pp.395-402
    • /
    • 2000
  • Recently, the deep excavations have been peformed to utilize the under ground space. As the ground excavation is deeper, the damage of the adjacent structure and the ground occurs frequently. The analysis of the retaining structures is necessary to the safety of the excavation works. There are many methods such as elasto-plastic, FEM, and FDM to analyze the displacement of the retaining structure. The elasto-plastic method is generally used in practice. In this thesis, GEBA-1 program by the Nakamura-Nakajawa elasto-plastic method was developed. The program for Windows was used the Visual Basic 6.0, and the Main of the program consists of three subroutines, SUB1, SUB2, and SUB3. The lateral displacement of the wall was analyzed by the developed program GEBA-1, SUNEX, and EXCAD, and compared with the measured displacement by the Inclinometer(at three excavation work sites). The excavation method of each site is braced retaining wall using H-pile. Each excavation depth is 14m, 14m, or 8.2m. The results of the analyses are the followings ① In the multi-layer soil, the lateral displacement by the GEBA-1 and EXCAD which is considering the distribution of the strut load is equal to the measured displacement. Elasto-plasto programs can't consider the change of the ground water in clay. Therefore, the analysis displacement was expected only 20% of the measured wall displacement. ③ At the final excavation step, the maximum lateral displacement of analysis and field occurred 7∼18m at the 85∼92% of the excavation depth. ④ The maximum lateral displacement in clay, as 50mm, occurred on the ground surface.

  • PDF