Mechanized tunneling induced ground movement and its dependency on the tunnel volume loss and soil properties

2019 ◽  
Vol 43 (4) ◽  
pp. 781-800 ◽  
Author(s):  
Chenyang Zhao ◽  
Arash Alimardani Lavasan ◽  
Thomas Barciaga ◽  
Tom Schanz
Keyword(s):  
Soil Properties ◽  
Ground Movement ◽  
Volume Loss ◽  
Mechanized Tunneling

scholarly journals Simplified Analytical Method for Predicting the Lateral Ground Displacements due to Shield Tunnelling

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Lianwei Sun ◽  
Zhong-chao Li ◽  
Rong-zhu Liang
Keyword(s):  
Analytical Method ◽  
Ground Movement ◽  
Volume Loss ◽  
Ground Displacement ◽  
Friction Forces ◽  
Grouting Pressure ◽  
Shield Tunnelling ◽  
Soil Volume ◽  
Slurry Shield ◽  
Ground Displacements

Earth pressure balance or slurry shield tunnelling will squeeze the subsoils and lead to lateral outward ground displacement. However, current methods to estimate the shield tunnelling-induced ground displacements generally use the methods based on the face unsupported tunnelling (e.g., New Austrian tunnelling and open shield excavation), which cannot predict the lateral ground movement due to shield tunnelling. In this paper, a novel simplified analytical method is proposed to predict the ground lateral displacement during the shield advancing process. The key shield tunnelling operation factors, including the additional pressure of cutter head, the friction forces around shield body, the back-fill grouting pressure, and the soil volume loss are all considered. The lateral ground displacements induced by the four former factors are calculated by using Mindlin’s solutions. The soil volume loss-induced lateral ground displacement is calculated by employing the expression introduced by Pinto and Whittle. Combining with the displacement obtained from all the factors, the analytical method for lateral ground displacement induced by shield tunnelling is obtained. The applicability of the proposed analytical approach is verified with three well-documented case histories involving slurry shield and EPB shield machines.

Applying the Method of Lagrange Multipliers to Derive an Estimator for Unsampled Soil Properties

2014 ◽  
Vol 11 (1) ◽  
pp. 15
Author(s):  
Set Foong Ng ◽  
Pei Eng Ch’ng ◽  
Yee Ming Chew ◽  
Kok Shien Ng
Keyword(s):  
Soil Properties ◽  
Lagrange Multipliers ◽  
Unbiased Estimator ◽  
Soil Property ◽  
Minimum Variance ◽  
Distance Method ◽  
True Value ◽  
A Site ◽  
Method Of Lagrange Multipliers ◽  
Inverse Distance

Soil properties are very crucial for civil engineers to differentiate one type of soil from another and to predict its mechanical behavior. However, it is not practical to measure soil properties at all the locations at a site. In this paper, an estimator is derived to estimate the unknown values for soil properties from locations where soil samples were not collected. The estimator is obtained by combining the concept of the ‘Inverse Distance Method’ into the technique of ‘Kriging’. The method of Lagrange Multipliers is applied in this paper. It is shown that the estimator derived in this paper is an unbiased estimator. The partiality of the estimator with respect to the true value is zero. Hence, the estimated value will be equal to the true value of the soil property. It is also shown that the variance between the estimator and the soil property is minimised. Hence, the distribution of this unbiased estimator with minimum variance spreads the least from the true value. With this characteristic of minimum variance unbiased estimator, a high accuracy estimation of soil property could be obtained.

AVAILABLE WAYS TO OPTIMIZE SOIL PROPERTIES IN APPLE ORCHARDS

2020 ◽  
Vol 16 (2) ◽  
pp. 41-63
Author(s):  
V.L. Zakharov ◽  
◽  
G.N. Pugachev ◽  
Keyword(s):  
Soil Properties ◽  
Apple Orchards

Geospatial comparison of three models to predict soil properties in semi-humid region of West Bengal, India

2018 ◽  
Vol 32 (5) ◽  
pp. 37
Author(s):  
Rajaram Majhi ◽  
Gouri Sankar Bhunia ◽  
Tapan Kumar Das ◽  
Pravat Kumar Shit ◽  
Rabindranath Chattopadhyay
Keyword(s):  
Soil Properties ◽  
West Bengal ◽  
Humid Region
Sign in / Sign up

Export Citation Format

Share Document