Effective evaluation of pressure relief drilling layout for reducing rock bursts and sensitive factor analysis

2021 ◽  
Vol 14 (23) ◽  
Author(s):  
Jing Zuo ◽  
Shanchao Hu ◽  
Xuedong Zhou ◽  
Chenxi Zhang ◽  
Yong Guo
2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Shan-chao Hu ◽  
Yun-liang Tan ◽  
Jian-guo Ning ◽  
Wei-Yao Guo ◽  
Xue-sheng Liu

Fault-slip rock burst is one type of the tectonic rock burst during mining. A detailed understanding of the precursory information of fault-slip rock burst and implementation of monitoring and early warning systems, as well as pressure relief measures, are essential to safety production in deep mines. This paper first establishes a mechanical model of stick-slip instability in fault-slip rock bursts and then reveals the failure characteristics of the instability. Then, change rule of mining-induced stress and microseismic signals before the occurrence of fault-slip rock burst are proposed, and multiparameter integrated early warning methods including mining-induced stress and energy are established. Finally, pressure relief methods targeting large-diameter boreholes and coal seam infusion are presented in accordance with the occurrence mechanism of fault-slip rock burst. The research results have been successfully applied in working faces 2310 of the Suncun Coal Mine, and the safety of the mine has been enhanced. These research results improve the theory of fault-slip rock burst mechanisms and provide the basis for prediction and forecasting, as well as pressure relief, of fault-slip rock bursts.


2021 ◽  
Author(s):  
Cunlu Li ◽  
Yanpeng Zhao ◽  
Haojie Xue ◽  
Jilu Wu ◽  
Wa Ma ◽  
...  

Abstract In recent years, with the extension of the coal mine at depth, rock bursts are more and more frequent. Therefore, the research of roadway support and pressure relief has become the key to prevent rock burst. In this paper, the primary high strength support and hydraulic fracturing pressure relief measures of roadway are studied and analysed. The primary high strength support emphasizes the matching characteristics of support materials, strengthen the protection of the active support to the roadway, and realize an integrated support system. Considering strong burst-prone area, the hydraulic fracturing is used to achieve pressure relief of surrounding rock mass, which can release and transfer the energy within the range of pressure relief. When there is energy release outside the range of protection system, the pressure relief region can absorb the energy so as to achieve the purpose of protecting the roadway. A field engineering case is applicated, the results shown that the stress of roadway surrounding rock and micro seismic energy significantly decreases, reducing the possibility of rock bursts.


2014 ◽  
Vol 989-994 ◽  
pp. 1747-1750
Author(s):  
Yong Tao Yu ◽  
Ying Ding

Anti-ship cruise missile (ASCM) attack route meets the needs of the attack mission will determine the effect of the subsequent attacks. According to research planning of anti-ship cruise missile route based on improved ANT algorithm by elitist strategy. The first is sensitive factor analysis of route planning based on operational requirements. Second is established an objective function and constraints set of route planning, achieved anti-ship cruise missile route planning model. Finally, based on specific objectives, situation and the user's strategies, it can use improved ANT algorithm to plan anti-ship cruise route.


1977 ◽  
Vol 20 (2) ◽  
pp. 319-324
Author(s):  
Anita F. Johnson ◽  
Ralph L. Shelton ◽  
William B. Arndt ◽  
Montie L. Furr

This study was concerned with the correspondence between the classification of measures by clinical judgment and by factor analysis. Forty-six measures were selected to assess language, auditory processing, reading-spelling, maxillofacial structure, articulation, and other processes. These were applied to 98 misarticulating eight- and nine-year-old children. Factors derived from the analysis corresponded well with categories the measures were selected to represent.


2001 ◽  
Vol 120 (5) ◽  
pp. A51-A52 ◽  
Author(s):  
B FISCHLER ◽  
J VANDENBERGHE ◽  
P PERSOONS ◽  
V GUCHT ◽  
D BROEKAERT ◽  
...  

2015 ◽  
Vol 74 (3) ◽  
pp. 119-127 ◽  
Author(s):  
Martine Bouvard ◽  
Anne Denis ◽  
Jean-Luc Roulin

This article investigates the psychometric properties of the Revised Child Anxiety and Depression Scale (RCADS). A group of 704 adolescents completed the questionnaires in their classrooms. This study examines potential confirmatory factor analysis factor models of the RCADS as well as the relationships between the RCADS and the Screen for Child Anxiety Related Emotional Disorders-Revised (SCARED-R). A subsample of 595 adolescents also completed an anxiety questionnaire (Fear Survey Schedule for Children-Revised, FSSC-R) and a depression questionnaire (Center for Epidemiological Studies Depression Scale, CES-D). Confirmatory factor analysis of the RCADS suggests that the 6-factor model reasonably fits the data. All subscales were positively intercorrelated, with rs varying between .48 (generalized anxiety disorder-major depression disorder) and .65 (generalized anxiety disorder-social phobia/obsessive-compulsive disorder). The RCADS total score and all the RCADS scales were found to have good internal consistency (> .70). The correlations between the RCADS subscales and their SCARED-R counterparts are generally substantial. Convergent validity was found with the FSSC-R and the CES-D. The study included normal adolescents aged 10 to 19. Therefore, the findings cannot be extended to children under 10, nor to a clinical population. Altogether, the French version of the RCADS showed reasonable psychometric properties.


Sign in / Sign up

Export Citation Format

Share Document