高寒地区深厚覆雪钢波纹板棚洞减载优化设计

为解决隧道入口覆雪钢波纹板棚洞在深厚积雪荷载作用下变形过大的问题,本文以新疆某隧道为工程依托,提出了制造两侧冰柱、制造上侧冰拱、冰柱冰拱耦合、冰柱冰拱EPS板耦合四种减载优化设计方案,并使用有限元软件ABAQUS分析四种方案的受力变形情况及可行性。结果表明：四种减载优化设计方案均极大地降低了钢棚洞的应力和变形,结构应力和变形满足设计规范允许值;马斯顿的“等沉面”土压力理论可以应用于堆积雪体中,增大内外雪柱沉降差,降低结构所受竖直压力;柔性填料EPS板在高覆雪工况中有一定的减载效果,但并没有在高填方土体中效果显著,在高覆雪工况中减载优先推荐加密钢波纹板棚洞周围雪体来达到减载的效果。

Optimal Design of Load Shedding for Deep Snow Covered Steel Corrugated Plate Shed in High Altitude Cold Regions

In order to solve the problem of excessive deformation of the snow-covered steel corrugated plate shed at the entrance of the tunnel under the action of deep snow load, this paper taked a tunnel in Xinjiang as the project support, and proposed four load reduction optimization design schemes, namely, manufacturing icicles on both sides, manufacturing ice arches on the upper side, icicles and ice arches coupling, and icles and ice arches EPS plate coupling. The finite element software ABAQUS was used to analyze the stress, deformation and feasibility of the four schemes. The results show that the stress and deformation of the steel shed are greatly reduced by the four load reduction optimal design schemes, and the structural stress and deformation meet the allowable values of the design code. Marston''s theory of "equisettled surface" earth pressure can be applied to the piled snow body to increase the settlement difference between the inner and outer snow column and reduce the vertical pressure on the structure. The flexible material of EPS plate has a certain load reduction effect in the high snow condition, but it is not significant in the high fill soil. In the high snow condition, it is recommended to give priority to encrypt the snow body around the corrugated steel plate to achieve the load reduction effect.