<p>Argillaceous slate, a typical metamorphic rock with highly developed bedding. The problem of slope anchoring support caused by the layering properties of argillaceous slate has gradually attracted the attention of the engineering community. Tiothis article relies on the highway slope project of the C9 block of Binjiang New Town. The mechanical experiments such as uniaxial compression, triaxial compression and Brazilian split tests were conducted on argillaceous slate with varying bedding dip angles. The field grouting test of the research slope was carried out. The effects of grouting pressure, bedding dip angle and grouting angle on the diffusion were discussed. Based on the test parameters and engineering data, the numerical model of layered argillaceous slate slope is established to carry out the numerical simulation test of axial pullout of anchor bolt. By introducing a diffusion coefficient and leveraging numerical analysis results, the study improves the anchorage force of the bolt in the specification, and further proposes a revised formula for calculating anchorage force, applicable to uniquely shaped anchors.</p>