Construction Efficiency Analysis of Shield Tunnelling in Ji’nan R1 Yu-Wang Section

Abstract

Based on the shield tunnel practice of Yu-Wang section in Ji’nan Rail Transit Line R1, the energy and resource consumption, and environmental impaction on the shield tunnel were researched to estimate the engineering quantity accurately and resolve estimation difficulties when bidding for rail tunneling projects. The consumption of electric energy, water resources, soil conditioning agent and grouting fluid during the construction process were quantified according to an investigation of shield construction parameters from the first 100 rings of the launching section. It is shown that the power consumption is relatively stable during segments installation, while it is mainly related to formation factors (shear wave velocity), the cutter head working time and construction parameters for the tunnelling stage. There is a positive correlation between the ring power consumption with formation shear wave velocity and the cutter head working time of each ring. And a clear linear correlation between the total power and the advancing speed, the cutter torque and the power of the cutter head is severally presented. The cutter head working time is around 20 min to 40 min and the power consumption is between 270 kWh to 580 kWh for each ring. The cumulative industrial water consumption is mainly between 1100 L to 4050 L per ring, and it is positively correlated with the cutter head working time. The total amount of solution and mixed liquid of foam in each ring are arranged 800 L to 2700 L and 60 L to −220 L, respectively. There is a significant positive correlation between them and the cutter head working time in each ring. The cumulative grouting amount of each ring is between 3100 L to 7000 L. Nevertheless, there is no obvious correlation between the cutter head working time.