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The Gaoloushan Tunnel in Longnan City, Gansu Province, China, frequently experiences rockburst disasters due to high in-situ stress. Managing rockburst in deep-buried tunnels remains a challenging issue. This paper employs RFPA (Rock Failure Process Analysis) software to establish a calculation model of constant resistance and large deformation (CRLD) anchorages and analyzes the effects of different support methods and pre-stress levels on rockburst. We simulate the process of tunnel rockburst disasters and find that ordinary anchor support incurs rockburst on the right arch waist and arch top, forming a V-shaped explosion pit. CRLD anchor support has several advantages in rockburst control, such as more uniform stress distribution in the surrounding rock, a uniform distribution of plastic zones, less noticeable damage to the tunnel, and effective control of the arch top displacement. The effectiveness of the CRLD anchor support under varying pre-stress conditions shows that a higher pre-stress results in a smaller plastic zone of the surrounding rock and arch top displacement and a lower number of acoustic emission signals, which better explains the excavation compensation effect. Moreover, adding long anchorages in the deep surrounding rock area can better control rockburst and reduce surrounding rock deformation. Based on these findings, we propose a comprehensive control system that combines long and short anchorages and provides the optimal scheme based on calculations. Therefore, by using high-prestress CRLD anchor support and the combination of long and short anchorages at critical positions, we can enhance the integrity of the surrounding rock, effectively absorb the energy released by the surrounding rock deformation, and reduce the incidence of rockburst disasters. [ABSTRACT FROM AUTHOR]

In order to effectively prevent and control the rutting problem of asphalt pavement in the deep loess area of Eastern Gansu and reduce road diseases, diatomite was added into the asphalt mixture for laboratory tests. Through Marshall test and rutting test, the optimum mix proportion of the diatomite asphalt mixture, and the optimal mix amount of the diatomite in this area were determined. The pavement performance of activated diatomite asphalt pavement and SBS asphalt pavement in this area is compared and analyzed through laboratory tests and on-site road paving. The test results show that under the same ambient temperature, the activated diatomite asphalt pavement has the advantages of lower surface temperature, high stability, and low-water permeability coefficient than SBS modified asphalt pavement. In addition, by fitting the fatigue test data of these two asphalt pavements, it is found that the fatigue life of diatomite asphalt mixture is more sensitive to the change in stress level and has better fatigue resistance. Therefore, it is concluded that the use of diatomite modified asphalt pavement in the loess area can improve the temperature stability of the pavement, prolong the service life, and reduce the cost of construction, which can be popularized. [ABSTRACT FROM AUTHOR]