scholarly journals A Predictive Model of Mining Collapse Extent and Its Application

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Jia Nan ◽  
Cheng Liu ◽  
Yi Liu
Keyword(s):  
Bearing Capacity ◽  
Evaluation Model ◽  
Water Environment ◽  
Slip Angle ◽  
Collapse Mechanism ◽  
Rock Body ◽  
Metal Mine ◽  
Ore Body ◽  
Grouting Reinforcement ◽  
Reinforcement Program

To reveal the mechanical behavior mechanism of collapse and to control risks effectively, the instability extent of the collapse area was established through theoretical mechanics and numerical methods, taking one metal mine as a case study; on this basis, a routine reinforcement program was determined, and the effect of the program was evaluated. The results show the following. (1) Analytical formulas of the critical slip angle and the collapse height of the ore body were derived by the mechanics method, and the rock mechanics parameters were obtained by field coring and physical and mechanical experiments. The slipping line angle increases along with uniform force Q and is inversely proportional to the bending stiffness. Meanwhile, the calculation formula for the maximum subsidence of ore body was deduced. (2) Numerical results can be used to determine the basic form of the collapse area, and a “U-shaped” collapse area formed when a plastic area passed completely through, resulting in the overall destruction. (3) The grouting reinforcement program includes “determining the instability region ⟶ roadway temporary support ⟶ improve the water environment and surrounding rock bearing capacity ⟶ mining planning” which were determined on the basis of prediction. (4) The hierarchical structure of the rock body and filling were improved combined with the Delphi method, and the grouting effect evaluation model was constructed and verified using the improved FD-AHP method; the evaluation value indicating that the grouting reinforcement improved the bearing capacity of ore body and filling body in collapse area. The research results provide systematic reference and technical support for the analysis of stope collapse mechanism, prediction of hidden trouble, and the subsequent mining.

Casing Bearing Capacity with Shear Load for Shale Gas Wells

2020 ◽  
Vol 993 ◽  
pp. 1190-1195
Author(s):  
Shang Yu Yang ◽  
Jian Jun Wang ◽  
Jia Wen Han ◽  
Hang Wang ◽  
Li Hong Han
Keyword(s):  
Bearing Capacity ◽  
Shale Gas ◽  
Failure Modes ◽  
Oil And Gas ◽  
Evaluation Model ◽  
Radial Deformation ◽  
Shear Load ◽  
Gas Wells ◽  
Fracturing Process ◽  
Casing Deformation

Casing radial deformation during complex fracturing process was seriously for shale gas wells in Sichuan district of China, and the average casing deformation rate in the region is of 50%. The bridge plug, perforating gun and other tools cannot successfully pass with deformed casing. Aiming at the 3-D logging morphology for deformed casing of shale gas wells, the failure modes and mechanisms were analyzed by using elasticity and theoretical mechanics. Many factors were evaluated and integrated to achieve quantitative evaluation model including geology feature, wellbore trajectory, cement property, casing material and hydrofracture process. With the aid of the self-developed unconventional oil and gas well casing simulation test equipment, the casing bearing capacity with shear load were carried out, established the relationship between shear load value and radial deformation, and further constructed the casing failure criterion with shear force. This work can provide technical support for casing design and selection in shale gas wells.

Water Environment Random Evaluation Model based on the improved TOPSIS method and Bayesian Theory and its Application

2019 ◽  
Vol 46 (3) ◽  
pp. 344-352
Author(s):  
Jinchao Xu ◽  
Yaqian Chen ◽  
Jun Zhao ◽  
Qingfeng Hang ◽  
Xuechun Li
Keyword(s):  
Evaluation Model ◽  
Water Environment ◽  
Bayesian Theory ◽  
Topsis Method ◽  
Model Based

scholarly journals Study On The Law Of Ground Strata Subsidence And Movement Induced By Caving Mining Of Slowly Inclined Large And Thick Ore Body

2018 ◽  
Vol 53 ◽  
pp. 03062
Author(s):  
Li Teng ◽  
Fu Jianxin ◽  
Song Weidong
Keyword(s):  
Underground Mining ◽  
Ground Surface ◽  
Beam Theory ◽  
Tectonic Stress ◽  
Collapse Mechanism ◽  
Surface Movement ◽  
Strata Movement ◽  
Leading Role ◽  
Metal Mine ◽  
The Law

Taking the Western District of Chengchao Iron Mine as engineering background, based on the GPS monitoring data of nearly 8 years and the record of the ground surface movement, the law of ground strata subsidence and movement is studied. The studies have shown that the surface movement caused by underground mining has the characteristics of time delay and displacement angle development has the law of jumping. The strata movement caused by mining is divided into the stage of overlying strata collapse and the collapse stage of surrounding rock to goaf. In the first stage, the vertical stress plays a leading role and rock failure is shown as a regular barrel collapse. In the second stage, horizontal tectonic stress plays a leading role and the collapse mechanism of rock strata can be explained by the cantilever beam theory. According to the mechanism of strata movement analysis, strata movement of Chengchao Iron is divided into six regions, which respectively included vertical subsidence area, toppling sliding zone, dumping area, deformation zone, cumulative deformation area and undisturbed zone. The results of this paper can provide a theoretical basis for the surface movement prediction of caving mining in similar metal mine.

scholarly journals Torsional Stability Assessment of Columns Using Photometry and FEM

Buildings ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 162
Author(s):  
Krzysztof Wierzbicki ◽  
Piotr Szewczyk ◽  
Wiesław Paczkowski ◽  
Tomasz Wróblewski ◽  
Szymon Skibicki
Keyword(s):  
Bearing Capacity ◽  
Laser Scanning ◽  
Structural Changes ◽  
Industrial Structure ◽  
Critical Force ◽  
Collapse Mechanism ◽  
Plant Structure ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Soil Subsidence

This paper presents a numerical analysis of the load-carrying capacity of steel open-section columns of a coal power plant structure. The structure was subjected to soil subsidence, which led to considerable structural deformations and damages. As a result, additional stresses appeared in the structure, and the static scheme of the structure was changed. To assess the influence of structural changes on the safety of the structure, a detailed investigation was necessary. Laser scanning was used to collect information concerning the geometry of structural elements. Results of the scanning were implemented in a numerical model of the structure. A complex finite element method (FEM) shell model of the column in ABAQUS software was developed. Torsional buckling stability analysis of column members was carried out. Different boundary conditions depending on the type of column connections to other elements were considered. Torsional deformations were treated as imperfections. Analysis showed that the connections of bracing elements, e.g., beams in multilevel frame, directly affected the collapse mechanism and load-bearing capacity of the investigated element. Finally, the paper showed that an appropriate change in the connections between the analyzed column and multilevel frame beams prevents the column from twisting, thereby increasing the critical force and load-bearing capacity of the analyzed industrial structure.

Influences and Countermeasures of the Shale Gas Exploitation on Water Environment

2014 ◽  
Vol 522-524 ◽  
pp. 1039-1044
Author(s):  
Qiu Lei Guo ◽  
Shu Heng Tang ◽  
Yi Wan ◽  
Er Ping Fan
Keyword(s):  
Shale Gas ◽  
Southwest China ◽  
Evaluation Model ◽  
Water Environment ◽  
Water System ◽  
Underground Water ◽  
Gas Production ◽  
Production Technologies ◽  
Negative Impacts ◽  
Improvement Of Legislation

When energy crisis is somewhat relieved by the shale gas production, serious negative impacts are simultaneously created to the environment e.g. the regional underground water system will be seriously damaged. Currently, the shale gas production, which is blossoming in China at present, centralizes primarily in the South-west area, where the hydrological environment is quite complicated and pretty weak. In this paper, three threatens caused during the shale gas exploitation is summarized and the crisis source is also outlined. Furthermore, the probable solutions aiming at these problems are discussed, thereby the concept of ‘Water resources tolerance ability evaluation model in SouthWest China’ being proposed. This paper emphasizes that the further enhancement of environment monitoring, improvement of legislation in the related areas as well as domestic adjustment of production technologies are critical to balance the industrializing production and sustainable development.

Floodwater Utilization Integrated Risk Evaluation Model Based on D-S Evidential Theory

2012 ◽  
Vol 599 ◽  
pp. 787-794
Author(s):  
Yuan Xiang Zhao ◽  
Yan Min Zhang
Keyword(s):  
Decision Making ◽  
Risk Evaluation ◽  
Evaluation Method ◽  
Evaluation Model ◽  
Water Environment ◽  
Flood Management ◽  
Water Resources Systems ◽  
Integrated Risk ◽  
Floodwater Utilization ◽  
Risk Evaluation Model

According to more and more serious problems of water scarcity, water pollution and deterioration of water environment in homeland, floodwater utilization becomes an important content in flood management and a critical solution for above problems. However, because of the uncertainty and subjective factor in the hydrology and water resources systems, floodwater utilization is a risk decision-making and the evaluation on the risk reasonably becomes an important decision-making reasoning problem. Traditional risk evaluation method considers uncertainty of things, but has little study on incompleteness of things and uncertainty of human’s subjective decision. An integrated risk evaluation model of floodwater utilization is presented based on D-S theory which can solve these problems successfully and with a case study, some benefit conclusions are provided.

Study on Regional Water Environment Carrying Capacity during the Process of Urbanization - A Case in Jining City

2011 ◽  
Vol 281 ◽  
pp. 253-257 ◽  
Author(s):  
Na Li ◽  
La Chun Wang
Keyword(s):  
Water Management ◽  
Sustainable Development ◽  
Economic Development ◽  
Bearing Capacity ◽  
Carrying Capacity ◽  
Water Environment ◽  
Scientific Basis ◽  
Socio Economic Development ◽  
Process Of Urbanization ◽  
Regional Water

The regional water environment carrying capacity (WECC) is defined as the bearing capacity of water environment for human activity in a certain state, a region and a time, reflecting the coordination between regional water environment and socio-economic development. Using the fuzzy comprehensive assessment principle, on the based of determining the weight of each index and the classification standard of index, the paper evaluated the water environment carrying capacity of Jining City form 2007~2009. The results show that the water environment carrying capacity of Jining City is still at a relatively low level, and remains to be improved further, which should provide scientific basis for the regional water management and sustainable development strategies.

scholarly journals Study on the strategy of improving urban resilience from the perspective of sponge city construction

2020 ◽  
Author(s):  
Fujun Xia ◽  
Keyword(s):  
Research Methods ◽  
Quantitative Research ◽  
Model Simulation ◽  
Evaluation Model ◽  
Water Environment ◽  
Urban Resilience ◽  
Sponge City ◽  
Quantitative Research Methods ◽  
Main Research ◽  
City Construction

Urban resilience refers to the ability of a city to cope with disasters and recover its basic functions rapidly. Urban transportation, urban infrastructure, urban public policy-making and other aspects can improve the resilience of the city. At present, the urban water environment in China is still deteriorating, and the rainstorm and waterlogging disasters are still frequent. Therefore, the author chooses the sponge city construction to study the strategies to improve the urban resilience. The author chooses two aspects of urban storm and waterlogging disaster control and surface runoff, which are closely related to the improvement of urban resilience, as the main research objects, selects specific evaluation indexes and proposes calculation functions, and adopts multiple research methods such as typical case study, spatial model simulation quantitative analysis, statistical analysis and empirical research, through arc GIS analysis, PCSWMM modeling and grasshopper data-based research By means of design and horizontal comparative study of three practical cases, this paper makes a qualitative and quantitative study on the strategy of sponge city construction performance to improve the city's resilience, and the quantitative research is mainly used. There are two main achievements in this study: a set of quantitative research methods to improve the resilience of sponge city construction is preliminarily explored through the application of the evaluation model; some strategies to improve the resilience of sponge city construction are proposed.

Sign in / Sign up

Export Citation Format

Share Document