装配式波纹钢棚洞的施工方法及受力特性研究

Construction Method and Mechanical Characteristics of Prefabricated Corrugated Steel Shed Tunnel

装配式波纹钢拱形棚架对比传统混凝土现浇棚洞,更适用于山区、自然灾害频发地区等的公路建设。本文依托云南省亚巴明洞工程,研究了装配式波纹钢棚架施工工法的原理和适用范围;结合具体的施工流程,分析了该工法的特点与优势,以及在特殊工况中的应用情况;根据亚巴明洞棚架工程实际情况,建立了有限元模型计算在正常工况与泥石流工况下的竖向沉降,水平位移与应力,并对影响波纹钢棚架受力的因素进行了参数稳定性分析。在此基础上得出了以下结论:(1)采用装配式施工的新型波纹钢棚架相较于传统混凝土现浇棚架而言,可以有效缩短施工工期、降低施工成本、保护环境,同时受力性能良好,适应变形的能力强,具有较为广阔的应用前景和工程实践意义;(2)采用装配式拼装替代现浇支架施工,可实现半幅施工保证通行,适用于易发生滑坡,泥石流等地质灾害或通行压力大的路段;(3)混凝土厚度对于波纹钢棚架结构的变形和受力的影响最大,波纹钢波距-波高其次,波纹钢壁厚的影响较小。因此在设计施工中宜将混凝土厚度作为重点因素考虑。

Comparing with the concrete shed tunnel,corrugated steel shed tunnel is more suitable for highway construction in the mountain and areas where natural disasters occur frequently.Based on the Yaba shed tunnel project in Yunnan Province,this paper studied the principle and applicable scope of the construction method of prefabricated corrugated steel shed.The principle,applicable scope and special applications of the method were analyzed combining the construction process.According to the situation of the project,a finite element model was established to calculate the vertical settlement,horizontal displacement and stress under normal conditions and debris flow conditions.Finally,the factors affecting the stress of corrugated steel sheds were analyzed.On this basis,the following conclusions are drawn:(1)Compared with the traditional concrete sheds,the assembled corrugated steel shed tunnel can effectively shorten the construction period,reduce construction costs,and protect the environment.Because of its well mechanical behavior,it has great application prospects and practical significance.(2)Because this uses an assembly method,this method can achieve half-width construction to ensure the traffic.It is suitable for high traffic pressure road and the areas where geological disasters frequently occur,like landslides and debris flows.(3)The thickness of the concrete has the greatest influence on the deformation and stress of the corrugated steel shed structure,followed by the corrugated steel wave pitch-wave height,and the influence of the corrugated steel wall thickness is small.Therefore,the thickness of concrete should be considered as a key factor in design and construction.