土压平衡盾构螺旋输送机配置选型研究

螺旋输送机是土压平衡盾构的排土装置,是土压平衡盾构的重要组成之一。它具有排渣、形成土塞保持土仓内土压稳定、通过控制排土速度实现动态土压平衡稳定开挖面三大功能。根据不同的施工水文地质条件,对螺旋输送机进行正确地配置选型,是盾构方案设计过程中的关键环节之一。若配置不当,将会造成喷涌、磨损、无法在掘进中途维修等严重后果,导致盾构施工无法正常进行。在介绍螺旋输送机工作原理、受力特征的基础上,结合不同的盾构施工水文地质条件对螺旋输送机配置选型进行分析研究,提出了土压平衡盾构螺旋输送机配置选型标准,并重点讨论针对复合地层的螺旋轴耐磨块结构设计。最后以成都为代表的砂卵石地层为例对该地区地铁隧道盾构施工的螺旋输送机进行配置选型。

Research on configuration of screw conveyor for earth pressure balance shield

Screw conveyor is the soil-transport equipment for Earth Pressure Balance Shield, it has three main functions： to transport soil, to form soil plug to maintain steady earth pressure in soil compartment and to keep earth pressure balance and dynamic stability of cutting face by controlling soil-transport speed. One of the key steps during design of Earth Pressure Balance Shield is to configure the screw conveyor accurately according to different hydrogeological conditions. If configuration improper, it will lead serious result such as spew, wear and unable to maintain during tunnelling. Based on studying of the working principle and mechanical characteristics of screw conveyor, and combine research result of relationship between hydrogeological conditions and configuration of screw conveyor, the screw conveyor configuration criteria for Earth Pressure Balance Shield is proposed, then to focus on the screw axis design for compound stratum. Finally, take Chengdu as an example of screw conveyor configuration for the compound stratum which is main composed of grit and srcee.