在薄弱岩石质量中的浅超大跨度道的杆螺栓的机械行为
Shaohui He1, Jiaxin He1, Jianfei Ma1
1School of Civil Engineering, Beijing Jiaotong University, Haidian District, Beijing 100044, China.
Materials (Basel, Switzerland)
|September 9, 2023
概括
来自道施工的爆炸振动严重影响了在弱岩石中杆螺栓的性能. 高达18米的螺栓长度显著改善了支,但更长的螺栓提供了减少的回报.
科学领域:
- 地质技术工程 地质技术工程
- 土木工程 土木工程是指土木工程.
- 铁路工程 铁路工程是指铁路工程.
背景情况:
- 在薄弱岩石中的浅超大跨度 (SSLS) 道存在独特的支挑战.
- 建筑振动可能会损害临时支,并影响螺栓的行为.
- 了解杆螺栓机制对于道的稳定性和安全性至关重要.
研究的目的:
- 在弱岩条件下的SSLS道中调查杆螺栓的机械行为.
- 分析建筑振动,岩石质量,建筑方案和螺栓长度对螺栓性能的影响.
- 为杆螺栓支系统提出优化措施.
主要方法:
- 在小北山二号道项目进行了为期八个月的实地测试.
- 精炼了SSLS道的有限差异数值建模.
- 实验室和现场测试,以校准数值模型参数.
- 监测和模拟螺栓轴力的比较.
主要成果:
- 试点道施工造成的爆炸振动对临时支造成了重大损坏,影响了螺栓轴力发展,增加了风险.
- 数值模型与现场监测数据进行了验证.
- 岩石质量极大地影响了杆螺栓轴承的特性.
- 施工方案会影响螺栓轴力的大小和发展,但不会影响它的最终分布.
- 杆螺栓的轴向力随着长度增加到18米而显著增加,超出这个范围的收益有限.
结论:
- 在弱岩SSLS道中的杆螺栓性能对施工引起的振动和岩石质量敏感.
- 螺栓长度优化至关重要,在18米以上的回报率下降.
- 该研究为设计在具有挑战性的地质条件下有效的螺栓支系统提供了宝贵的数据和见解.
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