Numerical Modeling of Soil-Pipeline Interaction Mechanism Caused by Surface Subsidence due to Longwall Mining

2013 ◽  
Vol 838-841 ◽  
pp. 2202-2207
Author(s):  
Guo Ming Cheng ◽  
Wen Jie Xu ◽  
Hong Bin Chu
Keyword(s):  
Numerical Modeling ◽  
Cross Sections ◽  
Longwall Mining ◽  
Measurement Data ◽  
Interaction Mechanism ◽  
Surface Subsidence ◽  
Face Advance ◽  
Subsidence Basin ◽  
The Face

In China, Surface subsidence caused by underground coal mining has affected the safe operation of pipelines in recent years. Take the coal mine in Shanxi section of the west-east gas pipeline as case study, numerical modeling was adopted to study the interaction mechanism of the soil-pipeline caused by longwall mining, and the numerical model was calibrated with the measurement data. The results reveal that the soil-pipeline interaction undergoes an evolution process from synchronization to separation during the subsidence process. The peak stresses on the pipeline at cross-sections occur generally above the centre of the corresponding subsidence basins at different stages of face advance, and the maximum stress on the pipeline appeared at about 150m above the centre of the subsidence basin as the face advances 300m.

scholarly journals Ground Response and Mining-Induced Stress in Longwall Panel of a Kilometer-Deep Coal Mine

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Zhaohui Wang ◽  
Shengli Yang ◽  
Guoliang Xu ◽  
Zhijie Wen
Keyword(s):  
Principal Stress ◽  
Longwall Mining ◽  
Vertical Plane ◽  
Field Measurements ◽  
Face Advance ◽  
Concentration Coefficient ◽  
Peak Point ◽  
Longwall Panel ◽  
The Face ◽  
Major Principal Stress

In order to improve ground control of the longwall mining, ground response and mining-induced stress in the longwall panel of a kilometer-deep coal mine are investigated in this study. Field measurements on abutment stress, roof displacement, and fracture development indicate that the region influenced by the longwall mining reaches 150 m ahead of the longwall face. Failure scope of the coal seam, where mining-induced fractures are well developed, ranges from 10 to 13 m inward the face line. Vertical stress concentration coefficient reaches 2.2. Based on the field measurements, a numerical model is moreover developed and utilized to examine the response of the principal stress to the longwall mining. The concentration coefficient, peak point location, and influence scope of the principal stress gradually become stable with an increase in face advancement. Regarding the major principal stress, the concentration coefficient and influence scope are 2.4 and 152 m, respectively, and the peak point locates 13 m inward the face line, which are consistent with the field measurements. With respect to the minor principal stress, the referred coefficient and scope are 1.5 and 172 m, respectively, and its peak point location is 21 m ahead of the face line. The major principal stress in the coal seam rotates from vertical to horizontal direction in the vertical plane parallel with face advance direction. The maximum rotation angle reaches 20°. The minor principal stress first rotates into the referred vertical plane and then it rotates from horizontal to vertical direction at the same speed with the major principal stress in the same plane. Rotation angle of the principal stress in roof strata is greatly enlarged, the rotation trace of which is influenced by the longwall mining and vertical distance above the seam. Based on the relation between rotation trace of the principal stress and face advance direction, the influence of stress rotation on the stability of roof structure is discussed.

scholarly journals An investigation of Outlier Detection Procedures for CMM Measurement Data

2018 ◽  
Vol 220 ◽  
pp. 04002 ◽  
Author(s):  
Petr Chelishchev ◽  
Aleksandr Popov ◽  
Knut Sørby
Keyword(s):  
Outlier Detection ◽  
Cross Sections ◽  
Experimental Verification ◽  
Measurement Data ◽  
Coordinate Measuring Machine ◽  
Data Sets ◽  
Dimensional Measurement ◽  
Measuring Machine ◽  
Simulation Results

The paper analyses methods for outlier detection in dimensional measurement. The cross sections of an internal cylinder were inspected by CMM (coordinate measuring machine), and received data sets were employed for further investigation. The efficiency of Rosner’s and Grubbs’ methods for excluding outliers from the measuring data had been estimated. The method of Rosner had been defined as the most effective for this case study. The simulation results were confirmed by experimental verification.

Modeling of Surface Subsidence Based on Time Function

2011 ◽  
Vol 422 ◽  
pp. 318-321 ◽  
Author(s):  
Hao Liang Han ◽  
Bo Cui
Keyword(s):  
Dynamic Model ◽  
Dynamic Process ◽  
Underground Mining ◽  
Surface Subsidence ◽  
Time Function ◽  
Subsidence Basin ◽  
Section Function ◽  
New Time

Base on Knothe time function, a new time function was proposed by adding parameter which is approved more accurate in predicting surface subsidence than Knothe funciton. Combing this new time function with section function of surface subsidence basin, a dynamic model is proposed to predict surface subsidence induced by underground mining and a case study based on this model was carried out. The results illustrates this model is more accurate to reflect the dynamic process of surface subsidence

Dynamic Modeling of Surface Subsidence Induced by Underground Mining

2011 ◽  
Vol 382 ◽  
pp. 323-327 ◽  
Author(s):  
Hao Liang Han ◽  
Nai Lian Hu ◽  
Bo Cui
Keyword(s):  
Dynamic Modeling ◽  
Underground Mining ◽  
Surface Subsidence ◽  
Time Function ◽  
Dynamic Mode ◽  
Subsidence Basin ◽  
Iron Mine ◽  
Section Function ◽  
New Time

A new time function was proposed to cover the disadvantage of knothe time function in predicting surface subsidence by adding parameter k. The velocity and acceleration of the progressive surface subsidence obtained from this new time function were compared with actual subsidence data from an iron mine in China. Combining this new time function with section function of surface subsidence basin, a dynamic mode was proposed to predict surface subsidence induced by underground mining and a case study based on this model was carried out. It shows that this model accurately represents the actual subsidence pattern observed. Instruction

ANALISIS KINERJA ASURANSI SYARIAH MENGGUNAKAN PENDEKATAN MASLAHAH SCORECARD (Studi Kasus Pada PT. Asuransi Takaful Umum)

2020 ◽  
Vol 1 (1) ◽  
pp. 108-125
Author(s):  
Jaharuddin Jahar ◽  
Melia Rostiana ◽  
R Melda Maesarach
Keyword(s):  
Measurement Data ◽  
Secondary Data ◽  
Process Performance ◽  
Measuring Process ◽  
Case Study Design ◽  
Quantitative And Qualitative Research ◽  
A Value ◽  
Takaful Insurance ◽  
Collection Methods

The purpose of this study was to decide the elements of performance at PT. General Takaful Insurance, to find out how to measure performance using the scorecard approach that is by measuring process performance and results performance, and interpreting in the form of conclusions. In this study, researchers tested apply maslahah at PT. General Takaful Insurance with a case study design. This research is a type of quantitative and qualitative research because it uses measurement data through formulas and if interpretative qualitative, and the data used are primary and secondary data. Data collection methods used are observation, interviews and documentation. The results showed that PT. General Takaful Insurance received a value of the performance benefit process of 0.7 which indicates that the company simply applied benefits in terms of process performance. And behave the benefit of PT. General Takaful Insurance got a value of 0.89 which shows that the company is quite good in providing benefits to stakeholders and shareholders. Keyword: Performance, Insurance, Scorecard Maslahah

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