Abstract:

Fully grouted prestressed anchor is a new kind of structural anchor. Few researches have been carried out on analysis of the influence of anchor shape of borehole wall on its carrying capacity. Rolling shape of anchor borehole wall structural plane has self-affine fractal feature; the relationship among structural plane shear strength, liquid injection pressure, tensile load and structural plane fractal dimension D is analysed in detail; the calculation and analysis methods are established respectively. Generally, the applied liquid injection pressure should be less than compression strength of anchoring surrounding rock mass, and tensile load would increase as fractal dimension D increases; the instability judgment criterion of anchoring bearing strata and rock structural plane is determined; the anchoring performance of fully grouted prestressed anchor is discussed. The analysis gives some help for the structure design, test and appliance to the anchor.

Key words: fully grouted, dimensions, rock mass discontinuity, filling pressure, anchoring mechanism