This paper presents a numerical study on the pullout behavior of the rockholt grouted system. Among the complicated failure modes of the rockbolt grouted system, the crack of the grout is concerned here. A tri- linear...This paper presents a numerical study on the pullout behavior of the rockholt grouted system. Among the complicated failure modes of the rockbolt grouted system, the crack of the grout is concerned here. A tri- linear cohesive zone model （CZM） is used to simulate the inteffacial behavior of rockbolt-grout interface： and a plastic damaged model is adopted for the grout materials. The feasibility of the numerical method is verified by comparing the calculated results with the test observations. The numerical results indicate that two types of cracks of the grout materials can be identified as the inclined crack and the horizontal crack. The inclined crack forms firstly and then the horizontal crack. Both cracks can reduce the interracial shear stress and thus reduce the load transfer efficiency. Further analysis indicates that the crack of the gout material can induce the obvious drops of load capacity, which is not a safe failure mode. This study leads to a better understanding of the mechanism for rockbolt grouted system.展开更多
Based on the investigation of fiber influence on workability of self-compacting concrete (SCC), tests were carried out on two series of SCC rectangular simply supported beams, which were made of hooked steel fibers re...Based on the investigation of fiber influence on workability of self-compacting concrete (SCC), tests were carried out on two series of SCC rectangular simply supported beams, which were made of hooked steel fibers reinforced concrete with or without stirrups, subjected to four-point symmetrically placed vertical loads. The major test variables are steel fiber contents and stirrup ratios. The results indicate that the ultimate load significantly increases with the increase of fiber content; the addition of ...展开更多
基金financially supported by the National Natural Science Fund of China (Nos. 51304067 and 51104057)the Fund of Opening Laboratory for Deep Mine Construction, Henan Polytechnic University (No. 2012KF-01)the Education Department of Henan Province (No. 13A440311)
文摘This paper presents a numerical study on the pullout behavior of the rockholt grouted system. Among the complicated failure modes of the rockbolt grouted system, the crack of the grout is concerned here. A tri- linear cohesive zone model （CZM） is used to simulate the inteffacial behavior of rockbolt-grout interface： and a plastic damaged model is adopted for the grout materials. The feasibility of the numerical method is verified by comparing the calculated results with the test observations. The numerical results indicate that two types of cracks of the grout materials can be identified as the inclined crack and the horizontal crack. The inclined crack forms firstly and then the horizontal crack. Both cracks can reduce the interracial shear stress and thus reduce the load transfer efficiency. Further analysis indicates that the crack of the gout material can induce the obvious drops of load capacity, which is not a safe failure mode. This study leads to a better understanding of the mechanism for rockbolt grouted system.
基金Supported by National Natural Science Foundation of China (No. 50578026)
文摘Based on the investigation of fiber influence on workability of self-compacting concrete (SCC), tests were carried out on two series of SCC rectangular simply supported beams, which were made of hooked steel fibers reinforced concrete with or without stirrups, subjected to four-point symmetrically placed vertical loads. The major test variables are steel fiber contents and stirrup ratios. The results indicate that the ultimate load significantly increases with the increase of fiber content; the addition of ...
