Life cycle analysis and damage prediction of a longwall powered support using 3D numerical modelling techniques
- PDF / 6,347,677 Bytes
- 15 Pages / 595.276 x 790.866 pts Page_size
- 59 Downloads / 220 Views
ORIGINAL PAPER
Life cycle analysis and damage prediction of a longwall powered support using 3D numerical modelling techniques Sreenivasa Rao Islavath 1 & Debasis Deb 2 & Hemant Kumar 3 Received: 6 October 2017 / Accepted: 23 June 2019 # Saudi Society for Geosciences 2019
Abstract Powered shield support consists of structural members like hydraulic legs, canopy, base, goaf shield, lemniscate links and several pins connecting these members. All these members experience cyclic loading as the shearer cuts coal and the longwall face advances. During the operational life of a shield support, members may be damaged since loading conditions vary widely depending on the type of roof and floor strata. This study focuses on the analysis of responses of various members of a powered support in terms of stresses, minimum number of operational loading cycles for a given safety factor and the damage under cyclic loading conditions. Threedimensional finite element models of a longwall panel are firstly analysed having powered support, rock strata, coal seam and goaf to determine the typical loading patterns those may occur on top of the canopy. Then these loading patterns are applied on a digital twin shield structure as cyclic loads for estimation of fatigue responses of various members. The study reveals that the most effected zone of the entire shield structure lies in goaf shield between the connectors of two lemniscate links. The links are the major load-bearing members and hence, their connection with the base and pins are severely also affected due to cyclic loading. Keywords Powered support . Cyclic load . Fatigue failure . Operational life . Safety factor and damage Editorial handling: F. Dai Highlights • A full-scale three-dimensional 2-legged lemniscate link–type powered support is modelled along with coal seam, surrounding rock mass and goaf for the analysis of deformation, stresses and plasticity that may occur in shield as well as in rock mass. • A total of 216 numerical models are developed for different geo-mining conditions by varying main roof thickness, length of overhung, material properties of main roof and setting pressure of powered support. • The loading patterns estimated from the three-dimensional finite element analysis surrounded with rock mass, coal seam and goaf and these are applied on a single shield structure as cyclic loads for estimation of fatigue responses of various components of shield structure. • This study focuses on the analysis of responses of various components of powered support in terms of von Mises stresses, minimum operational cycles, safety factor and damage under cyclic loading conditions. • The study reveals that the most effected zone of the entire shield structure lies in goaf shield between the connectors of two lemniscate links. * Sreenivasa Rao Islavath [email protected] 1
Department of Mining Engineering, University College of Engineering, Kakatiya University, Kothagudem 507101, India
2
Department of Mining Engineering, Indian Institute of Technology, Kharagp
Data Loading...
