Study On Stress States And Supporting Effects Of Bolt Body

The thesis has studied the displacement and breaking mode of rod of rockbolts. Tests on the load and break of rods have been conducted in the laboratory, and the effects of installing angle of rods are analyzed on the break resulting from bending, and the bending moment of threaded segments is monitored during the installing of rockbolts, and the complex stresses are checked and calculated during the installing of prestress, and the effects of installing angle and torsion moment are analyzed on the load of rods, the possible causes have been discussed for the break of the parts of head and tail in the rods, and based on the above results, the proper angle of installing and reasonable torsion moment have been proposed. The state of load of rods has been theoretically analyzed on the condition of complex stress, and the mechanical model of critical sections has been built. The focus of study has been set on the beak of vulnerable threaded segments on the rear part of rods, and the effect of spherical lock and spinning center's location have been analyzed on the state of load in the threaded rear part of rods, and the break load of rods has been calculated under conditions of complex stress, and the measures of improvement have been proposed to relieve the detrimental loading factors. A series of numerical with ANSYS have been conducted to discuss the distribution of stress on different conditions: tension, bending, shearing and combined patterns, and the results from these analyses have been compared with the data from the laboratory anrd the theoretical analyses. The results of study have been applied in several roadways, and the states of load of rods have been monitored, and the reasonable support patterns have been provided, the factors detrimental to rods have been relieved and the security has been improved.