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In roadways with high ground stress or burial depths, the joints distributed within rock formations are subject to complex stresses and interlayer misalignments frequently. Rock bolts and cable bolts anchored in the rock formations are subject to tensile and shear forces. Most of the bolts used in roadway engineering are local anchored, resulting in insufficient shear strength at the bolt free end close to roadway surface and increasing bolts breaking. The anchor cable and C-shaped tube (ACC) is a highly prestressed cable bolt that can withstand high shear force in its free end. This paper examines the effect of the relationship between C-shaped tube length and joint location on the shear resistance of ACC by double shear tests. To fully exploit the ACC’s shear resistance, the C-shaped tube ends should be at least 30 cm beyond the joint. The effect of preload and concrete spray thicknesses on roadway deformation and plastic zone is investigated by numerical simulation. Results show that ACC and concrete spraying layer can form a stable extruded arch structure, so that the broken and soft rock within the loosen zone is in three-dimensional-stress state, effectively improving surrounding rock properties and controlling its deformation size. Based on these results, the ACC support design method is proposed.

In order to deeply understand the influence of different factors on the characteristic indicators of the double-row-pipe partial horizontal frozen body in the sand-gravel stratum under the effect of seepage flow, several sets of sand-gravel stratum frozen model tests were carried out based on the similarity theory. The research showed that (1) under the effect of seepage flow, the backwater surface of the horizontal frozen body is in the shape of a quadratic parabolic and the development velocity of the backwater surface is inversely proportional to the square of the freezing time. The influence of seepage velocity on the downstream length and the freezing front development velocity of the backwater surface is stronger than the refrigerant temperature; (2) overlap time of the second row of frozen soil column increases with the increase of the distance between frozen pipes and seepage velocity and decreases with the decrease of the refrigerant temperature. The influence of various factors on the overlap time follows the order as the distance between freezing pipes > seepage velocity > refrigerant temperature. The average development velocity of the upstream surface decreases with the increase of the seepage velocity and the refrigerant temperature and first increases and then decreases with the increase of freezing pipe spacing. The influence of various factors on the average development velocity follows the order as seepage velocity > the distance between freezing pipes > refrigerant temperature. In addition, through the regression analysis, the quantitative relationship between the maximum arrangement spacing of the frozen pipes, the seepage velocity, and the refrigerant temperature was obtained. The research results can provide a basis for large-area partial horizontal freezing construction in Beijing sand-gravel stratum.