土压平衡盾构改良渣土屈服应力分析

屈服应力是反映材料和易性的重要特征参数之一.依托武汉地铁6号线老关村出入段盾构隧道工程,开展室内盾构渣土塌落度试验,推导考虑塌落度桶形状效应的渣土屈服应力改进预测模型,进而分析不同含水率、不同掺入比和不同角砾含量条件下渣土屈服应力变化规律.结果表明:角砾黏土的塌落度试验值与含水率、泡沫剂掺入比和角砾含量呈正相关关系;通...

Analysis of Yield Stress of Improved Muck of Earth Pressure Balance Shield

Yield stress is one of the important characteristic parameters reflecting the workability of materials. Based on the shield tunnel project of the Lao Guan-cun entry and exit section of Wuhan Metro Line 6, an indoor shield slag slump test was carried out. An improved prediction model of the yield stress of muck considering the bucket shape effect of the slump was deduced. The variation law of the yield stress of the slag soil was analyzed under the conditions of different water content, different mixing ratio and different breccia content. The results show that the slump test value of breccia clay is positively correlated with water content, foaming agent blending ratio and breccia content. The effectiveness of the improved model in this paper was verified compared with experimental results and calculation results of other theoretical models. The yield stress of breccia clay has a negative correlation with the content of breccia, a non-linear negative correlation with the moisture content, and a linear negative correlation with the foaming agent mixing ratio. The relevant research results are expected to provide a theoretical basis for the reasonable improvement of the earth pressure balance shield tunnel muck, which has certain theoretical value and engineering significance.