关键词: 端锚粘结式锚杆, 加载模式, 极限锚固力, 室内试验

Abstract: In order to study the mechanical behaviors of anchorage segment of end-anchored and grouted bolts, we took cement water glass mortar end-anchored bolt body as research object and carried out repeated pull-out test in which dynamic load of small strain and high frequency is made equivalent to the load of high strain and low frequency. The test results show that the mode of dynamic load with small strain and high frequency is correct and reliable, and meets the requirements of the end-anchored model test. When the loading frequency is 430.882Hz, the stress and strain of end-anchor’s free deformation segment reach the maximum, and reach the minimum (approaching zero) far from the anchorage section. The axial stress distribution along the bolt is in approximation to the waveform between λ/2 wavelength of sine function. By analyzing the test results, we obtain the shear stress distribution along the bolt body, the displacement curve and the τ-u curve. The shear stress achieve the maximum at the anchorage deformation segment of end-anchor, and with the increase of the percentage and number of cyclic loading and unloading increment, the peak shear stress transmits and moves slowly to the bottom of the anchorage segment, eventually disenables the anchoring effect of anchored segment.

Key words: end-anchored and grouted bolts, loading mode, maximum anchor force, laboratory test