scholarly journals General deformation behavior of deep excavation support systems: A review

2022 ◽  
Vol 10 (1) ◽  
pp. 039-057
Author(s):  
Maher T. El-Nimr ◽  
Ali M. Basha ◽  
Mohamed M. Abo-Raya ◽  
Mohamed H. Zakaria

In geotechnical engineering, ground movement caused by excavations is a challenging issue. The excessive differential settlement generated by soil movement induced by wall deflection may cause damage to nearby structures. A detailed literature review on the general deformation behavior of deep excavation support systems is presented in this paper. Many factors, such as normalized horizontal deflection (δh-max/He%), vertical displacement (δv-max/He%), δvmax/δhmax ratio, settlement influence zone (Do), etc., can play significant roles in describing the deflection behavior of the excavation system. A descriptive analysis of the reviewed data was carried out. The concluded δh-max/He% values range between 0.17 to 1.5, with a mean value of 0.58 for soft clay, while in the case of sands and stiff clay soils δh-max/He% value ranges between 0.07 to 0.40, with a mean value of 0.20. δv-max/He% values range between 0.13 to 1.10, with a mean value of 0.49 for soft soil, while its value ranges between 0.02 to 1.10, with a mean value of 0.24 in the case of sands and stiff clay soils. The settlement influence zone (Do) reaches a mean distance of 2.3He, which falls within Do=1.5-3.5He in the case of soft clays, while Do reaches a mean distance of 2.0He and 3.0He in the case of sands and other stiff clay soils, respectively. The relationship between system stiffness and excavation-induced wall and ground movements was discussed. Unfortunately, the literature review offers limited data regarding system stiffness, the 3-D nature of excavation support systems, excavation processes, and time effects.

Religions ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 548
Author(s):  
Elliott Ingersoll ◽  
Sophia Elliott ◽  
Stephanie Drcar

UFGLI students comprise 34% of the students enrolled in four-year universities. Unlike some students, UFGLI students face internal and systemic barriers throughout their educational experience and their struggles are often dismissed and disregarded. Working and raising a family while taking courses, minimal support systems, and financial struggles require students to optimize their resources. We explore the issues of UFGLI students and the importance of their spiritual and religious supports using a literature review and a case study. Religious and spiritual identities are resources that should be explored and supported by staff at university counselling centers. Affirming UFGLI students’ religious and spiritual identities and understanding how religion and spirituality work in their lives can assist these students in their acclimation to and success at university.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Hanna Michalak ◽  
Paweł Przybysz

Abstract The paper will analyse and review the experience to date in determining the impact range of implementation of deeply founded structures on the displacement of the subsoil in the vicinity. With the background of these experiences, primarily empirical, the present possibilities of using numerical modelling to forecast the displacements of the terrain surface in various stages of works, that is, execution of deep excavation support systems, excavation-deepening phases with successive adding of struts, construction of underground levels and erection of the above-ground part of the building, will be presented. Based on the results of own research, conclusions on the use of 3D numerical models in spatial shaping and designing the structure of underground parts of new buildings erected in dense urban development will be presented. The characterised 3D numerical models were verified, taking into account the actual results of geodetic measurements of the completed buildings. Determining the range and forecasting the displacements of the subsoil are necessary for the design and implementation of investments due to the need to ensure the safety of erection and use of a new building and the buildings located within the area of influence.


2021 ◽  
Vol 1 ◽  
pp. 1300-1305
Author(s):  
Arti Ayuningtiyas ◽  
Benny Arief Sulistyanto

AbstractDuring the Covid-19 pandemic, nurses are at the forefront. Many nurses experience stress and fatigue due to increased workload. Stress and fatigue that is obtained at work, both physical and psychological fatigue, is known as Burnout. This study aimed to describe the incidence of Burnout experienced by nurses during the Covid 19 Pandemic. This research is a literature review. This study was looking for some articles from PubMed,Garuda, and Google Scholar, with keyword. There were 5 articles that matched the research inclusion criteria. Critical analysis of 5 articles used the JBI instrument. These articles used the mean calculation. In the Emotional Exhaustion category, the mean value was 22.75 and SD was 8.828. it meant that the burnout level in the Emotional Exhaustion category was at a moderate level. In the depersonalization category, the mean value was 7.54 with SD 4.248. it meant that the burnout level in the depersonalization category was at a moderate level. In the personal accomplishment category, the mean was 19.676 with SD of 6.7. it mean that the burnout level in this category was a high level. The nurses experience burnout during the Covid-19 pandemic. The Emotional exhaustion category is a moderate level, depersonalization is at a moderate level, and personal accomplishment is at a high level.Keywords: Nurse, Burnout, Covid-19 pandemic AbstrakDimasa pandemi Covid-19 perawat berada pada garda terdepan, banyak perawat mengalami stress dan kelelahan dikarenakan beban kerja meningkat. Stress dan Kelelahan yang didapat saat kerja baik itu kelelahan fisik maupun psikis dikenal dengan nama Burnout penelitian ini bertujuan untuk mendeskripsikan kejadian Burnout yang dialami Perawat selama Pandemi Covid 19. Penelitian ini adalah literatur review. Hasil pencarian artikel dari database online yaitu Pubmed,Garuda dan Google Scholar, dengan kata kunci di dapatkan 5 artikel yang sesuai dengan kriteria inklusi penelitian. Analisa telaah kritis terhadap 5 artikel menggunakan instrument JBI. Terdapat 5 Artikel yang menggunakan perhitungan mean di dapatkan hasil kategori Emotional Exhaustion nilai mean sebanyak 22.75 dan SD 8.828 dimana hasil menunjukkan level burnout pada level sedang. Kategori depersonalization dengan nilai mean 7.54 dengan SD 4.248 dimana hasil burnout pada level sedang. Kategori personal accomplishment hasil mean 19.676 dengan SD 6.7 dimana hasil burnout menunjukkan level tinggi. Dari 5 Artikel yang di telaah di dapatkan Perawat mengalami Burnout selama pandemic Covid-19, kategori Emotional Exhaustion berada pada level sedang, depersonalization berada pada level sedang, dan personal accomplishment pada level tinggi.Kata Kunci : Perawat, Burnout, pandemi Covid-19


2013 ◽  
Vol 35 (3) ◽  
pp. 25-43 ◽  
Author(s):  
Karolina Górska ◽  
Zbigniew Muszyński ◽  
Jarosław Rybak

Abstract This work discusses the fundamentals of designing deep excavation support by means of observational method. The effective tools for optimum designing with the use of the observational method are both inclinometric and geodetic monitoring, which provide data for the systematically updated calibration of the numerical computational model. The analysis included methods for selecting data for the design (by choosing the basic random variables), as well as methods for an on-going verification of the results of numeric calculations (e.g., MES) by way of measuring the structure displacement using geodetic and inclinometric techniques. The presented example shows the sensitivity analysis of the calculation model for a cantilever wall in non-cohesive soil; that analysis makes it possible to select the data to be later subject to calibration. The paper presents the results of measurements of a sheet pile wall displacement, carried out by means of inclinometric method and, simultaneously, two geodetic methods, successively with the deepening of the excavation. This work includes also critical comments regarding the usefulness of the obtained data, as well as practical aspects of taking measurement in the conditions of on-going construction works.


2013 ◽  
Vol 353-356 ◽  
pp. 614-618
Author(s):  
Lang Gao ◽  
Zhao Wen Tang ◽  
Quan Zhong Liu

Soil nailing has become an important excavation support system for its good performance and cost-effectiveness. It is complicated to predict deformation of soil nailing during excavating. The Artificial Neural Network (ANN) is developed very quickly these years, which can be applied in diverse applications such as complex non-linear function mapping, pattern recognition, image processing and so on, and has been widely used in many fields, including geotechnical engineering. In this paper, the artificial neural network is applied for deformation prediction for soil nailing in deep excavation. The time series neural networks-based model for predicting deformation is presented and used in an engineering project. The results predicted by the model and those observed in the field are compared. It is shown that the artificial neural network-based method is effective in predicting the displacement of soil nailing during excavation.


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