Experimental Study on Paste Production and Pipeline Transportation Characteristics of Earth Pressure Balance Shield Muck
Earth pressure balance shield is widely used in urban tunnel construction due to its high excavation efficiency and strong geological applicability.Traditional earth pressure balance shield generally uses the slag tapping method with the belt conveyor and the battery truck and the gantry crane,which is easy to cause mud and water splashing and harsh working conditions.The power consumption of the dilute phase pipeline transportation is huge,and the post-processing is cumbersome.The shield muck paste can be transported by pipeline full enclosed throughout the entire process with simple post-processing procedures.The basic physical properties and improvement characteristics of the typical shield muck was analyzed,and a loop pipe experimental unit was built for paste pipeline transportation using pump.The experimental study shows that the shield muck sample belongs to paste state when its slump is between 15cm and 25.2cm,and the shield muck paste with a slump of 19cm to 25cm could be pumped by pipeline.The greater the slump of the shield muck paste,the smaller the pipeline transmission resistance.The empirical model of pipeline transmission resistance was further obtained,and the improvement effect of foam agent was confirmed.The solidification experiment shows that the slightly weathered soil paste does not solidify for 23 hours,and the strongly weathered soil paste does not solidify for more than 33hours.The maintenance time for the pipeline transportation system is relatively sufficient.The research results provide a reference for the development of the pipeline transportation technology of shield muck paste.
万方数据
维普
