Relationship between lay distance and tensile mechanical properties and anchorage effect of mine anchor cable

LIU Shaowei; DOU Zhi; FU Mengxiong; JIA Housheng; WANG Baohua

doi:10.13225/j.cnki.jccs.2022.1469

Abstract：The mine anchor cable,which is mainly made of multiple steel strands,has the advantages of bendability,strong breaking resistance and low cost.It is widely used in the stability control of coal roadway surrounding rock,es-pecially the roadway roof.The lay length is one of the important parameters for making anchor cable,which is often ig-nored in coal mines because of the lack of understanding when selecting anchor cable.In order to explore whether the lay length parameter has an influence on the tensile mechanical properties and anchoring effect of the anchor cable,this paper combines theoretical analysis with laboratory tests to preliminarily clarify the influence of the lay length parameter on the geometric deformation characteristics of the anchor cable during tensile and understand its in-fluence mechanism on the anchorage force of the anchor cable.Based on the experimental data of anchor cable tension and anchorage drawing,a numerical simulation model was constructed.Compared with underground test results,the relationship between the lay length and the ultimate load and the maximum anchorage force was obtained.The optimal lay length which could give full play to the tensile mechanical properties and anchorage effect of the cable was also ob-tained.The results show that when the anchor cable is stretched,the lay length has a negative correlation with elonga-tion and a positive correlation with tensile limit load in a certain range.There is a certain geometric matching relation-ship between the cable and anchorage agent interface.When the lay length is reduced to 13 times of its nominal diam-eter,the maximum anchorage force increases with the decrease of the lay length.Considering the ultimate tensile load and maximum anchorage force of the anchor cable,it is found that the best lay length which can give full play to the tensile mechanical properties and anchorage effect of the anchor cable is 13-14 times of the nominal diameter.The research results increase the understanding of the influence of anchor cable lay length on its tensile mechanical properties,clarify the understanding of its anchorage mechanism,and provide a reference and theoretical support for the production of anchor cables and the selection of anchor cables in coal mines.