考虑温度效应的盾构法黏土-金属界面黏附力试验

Experimental on Tangential Adhesion of the Contact Surface Between Clay and Shield Cutter Head Considering Effect of Temperature

盾构在黏土地层掘进时,刀盘与土体的摩擦产生大量热量,高温环境会改变黏土对刀盘的黏附作用。采用自主设计的恒温黏附剪切仪,开展了室内试验,采用单因素分析方法分析了温度与其他因素(接触面压力、剪切速度、含水量、矿物含量、排水环境)对黏土–金属界面黏附力的影响规律。试验研究表明:接触面压力与切向黏附力呈正相关,剪切速度和含水量与切向黏附力呈负相关,土样稠度指数为0.5和0.8时温度变化对黏土切向黏附力影响较大;排水使得黏土的切向黏附力有随温度增大的趋势;温度升高致使黏土的切向黏附力有随温度减小的趋势;含水率越高的土样,越容易受到排水状态的影响,黏附力越早地随温度升高而出现拐点。

When shield tunneling in the clay stratum,the friction between cutterhead and soil generates a lot of heat.High temperature environment will change the adhesion between clay and cutterhead.Using the self-designed constant temperature adhesion shear instrument,indoor tests were conducted.The influence of temperature and other factors,including contact surface pressure,shear rate,water content,mineral content,drainage environment,on the adhesion force was analyzed by using the single factor analysis method.The results show that:the contact pressure is positively correlated with the tangential adhesion,and the shear velocity and water content are negatively correlated with the tangential adhesion force.When the soil consistency index is 0.5 and 0.8,the temperature has a great influence on the tangential adhesion force.The tangential adhesion increases with temperature due to drainage,while the tangential adhesion of clay decreases with temperature due to the rising in temperature.The higher the moisture content of soil sample,the more easily affected by the drainage state,and the earlier the inflection point of adhesion appears with the increase of temperature.