| 引用本文: | 陈保国,吴森,高琦,孙梦尧,袁山,吴雪婷.填土-EPS板蠕变下减载式涵洞土压力长期变化规律[J].哈尔滨工业大学学报,2025,57(3):46.DOI:10.11918/202302024 |
| CHEN Baoguo,WU Sen,GAO Qi,SUN Mengyao,YUAN Shan,WU Xueting.Long-term variation law of earth pressure of load-shedding culvert considering the creeps of fill-EPS slab[J].Journal of Harbin Institute of Technology,2025,57(3):46.DOI:10.11918/202302024 |
|
| |
|
|
| 本文已被：浏览 39次 下载 47次 |
码上扫一扫！ |
|
|
| 填土-EPS板蠕变下减载式涵洞土压力长期变化规律 |
|
陈保国,吴森,高琦,孙梦尧,袁山,吴雪婷
|
|
(中国地质大学(武汉) 工程学院,武汉 430074)
|
|
| 摘要: |
| 减载式涵洞改变了涵顶填土荷载的传递路径,使得上部填土荷载向减载块集中,从而降低涵洞顶板受到的土压力,但是在长期填土荷载下,土体与减载孔内的柔性填料会发生蠕变变形导致应力重分布。为了明确长期填土荷载作用下减载式涵洞的土压力变化规律与减载效果,利用模型试验探究了刚性地基条件下减载式涵洞在填筑砂土施工期间的荷载传递规律,根据试验结果验证了数值模型的正确性；再利用验证后的数值模型研究了填土荷载作用下,考虑减载孔内EPS柔性填料蠕变、路基填土蠕变,以及二者共同蠕变条件下,减载式涵洞的土压力长期变化规律。研究结果表明:刚性地基条件下,考虑EPS板蠕变时,工后30年涵顶土压力相对于填土结束时减小了25.4%,涵顶土压力减载效果随时间增长而增强,建议涵顶竖向土压力系数可取0.45；考虑填土蠕变或二者共同蠕变时,涵顶土压力波动式增大,并最终均趋近于填土自重压力,减载效果随时间增长逐渐减弱,建议涵顶竖向土压力系数可取1.1。对于黏性土路基,设计中如果不考虑长期填土蠕变引起的土压力重分布,很可能高估减载式涵洞的减载效果,从而导致结构病害。 |
| 关键词: 减载式涵洞 蠕变变形 应力重分布 长期土压力 土拱效应 |
| DOI：10.11918/202302024 |
| 分类号:TU432 |
| 文献标识码:A |
| 基金项目:国家自然科学基金(52178370) |
|
| Long-term variation law of earth pressure of load-shedding culvert considering the creeps of fill-EPS slab |
|
CHEN Baoguo,WU Sen,GAO Qi,SUN Mengyao,YUAN Shan,WU Xueting
|
|
(Faculty of Engineering, China University of Geosciences, Wuhan 430074, China)
|
| Abstract: |
| The load-shedding culvert changes the transmission path of the fill load on the culvert roof, causing the fill load to concentrate on the load shedding blocks, thereby reducing the earth pressure on the culvert roof. However, the soil and compressible material in the load shedding hole will creep with time under long-term fill load, leading to stress redistribution. In order to clarify the variation law of earth pressure and load reduction effect of the load-shedding culvert under the long-term fill load, the model test on rigid foundation was used to explore the load transfer law of the load-shedding culvert during the sand filling construction, and the correctness of the numerical model was verified according to the test results. Then the verified numerical model was conducted to analysis the long-term variation law of earth pressure of the load-shedding culvert by considering three different creeps conditions (i.e., the creep of EPS material in the load shedding hole, the creep of embankment fill, and both creeps). The results show that, on rigid foundation, considering the creep of EPS slab, the earth pressure at the top of the culvert decreases by 25.4% in the 30 years of post-construction compared with that at the end of soil filling, the load reduction effect of the earth pressure at the top of the culvert increases with time, it suggests that the vertical earth pressure coefficient on the culvert top can be taken as 0.45. When considering the fill creep or both creeps, the earth pressure at the top of the culvert fluctuates and finally approaches to the self-weight pressure of the fill soil, the load reduction effect gradually decreases with the increase of time, it suggests that the vertical soil pressure coefficient on the culvert roof can be taken as 1.1. For cohesive soil embankment, if the earth pressure redistribution caused by fill creep is not considered in the engineering design, the load reduction effect of the load-shedding culvert probably be overestimated and resulting in structural damage. |
| Key words: load-shedding culvert creep deformation stress redistribution long-term earth pressure soil arch effect |
|
|
|
|
