Free-fly rolling model of stone on rock slope and control techniques(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2018年01期
- Page:
- 25-31
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Free-fly rolling model of stone on rock slope and control techniques
- Author(s):
- CUI Zhe; SHI Yong-fei; MENG Jia-qi
- 1. School of Highway, Chang’an University, Xi’an 710064, Shaanxi, China; 2. Shaanxi Provincial Transport Planning Design and Research Institute, Xi’an 710075, Shaanxi, China; 3. CCCC First Highway Consultants Co., Ltd., Xi’an 710075, Shaanxi, China
- Keywords:
- road engineering; rock slope; elastic mechanics; rolling disaster; sand cushion; protective net
- PACS:
- U411
- DOI:
- -
- Abstract:
- Aiming the problem of rolling stone disasters of highway rock slopes, a theoretical analysis model of rock jumping and rolling was established. By deducing the trajectory equation of rock movement, the horizontal velocity and vertical velocity of the first drop point of rolling stone and the horizontal distance of the second drop point were derived. In addition, the horizontal distance of rolling stone falling into the structure surface and the impact energy on sand cushion were calculated, the depth of rock rolling into sand cushion was calculated, and the relationship between impact energy and depth was analyzed. At the same time, the impact pressure, the maximum normal compressive stress, the impact energy and the amount of indentation of rolling stone falling into sand cushion were derived. The proposed model was verified by two examples. According to the calculation results, a reasonable protection method was selected for the protection of rolling stone hazards. The results show that in the first example, the amount of indentation of rolling stone falling to sand cushion is 1.28 m, and the thickness of sand cushion on the designed structure is 2 m. Considering the safety reserve of structure, the distance of horizontal movement of rolling stone after hitting the slope is less than the horizontal distance from the impact point to road edge, and the impact energy of rolling stone flying down to the ground is 167 kJ. The passive protective net of AXI-015 (protection grade is 200 kJ) can effectively protect the structure and avoid accident. In the second example, the amount of indentation of rolling stone falling into sand cushion is 0.87 m, the impact energy is 124 kJ, and the thickness of sand cushion with 1.5 m is backfilled to the top of the designed hole. The passive protective net of AXI-015 (protection grade is 150 kJ) can effectively protect slope rolling rock hazards. The effect is obvious of which using proposed method for calculation and protection. At the same time, it is proved that the model can be implemented, which can provide useful guidance for similar projects in future.
Last Update: 2018-02-06