In the process of shield tunnel construction, the challenges brought by clay layers often give engineering teams a headache. Clay tends to cake and stick in front of the cutterhead and inside the soil chamber, causing poor muck discharge, higher cutter loads and even shutdowns for cleaning. This not only seriously affects construction progress but also increases equipment wear and maintenance costs.
Chemi Tech has an in-depth insight into this industry pain point and has developed a targeted shield tunnelling clay dispersant solution. The core of this solution is to chemically improve the properties of the soil, break the bonding force between clay particles, and make the clay easy to disperse and flow after excavation so that it can be discharged smoothly.
Our solution is divided into three steps. The first step is on-site soil sampling and analysis, assessing the clay type, water content and plasticity index to provide an accurate basis for product selection and dosage. The second step is custom formulation: our technical team will, according to the analysis results, prepare a suitable dispersant combination to ensure it matches the on-site soil and water conditions. The third step is injection and monitoring: during shield tunnelling, the dispersant is mixed into the soil chamber or in front of the cutterhead at a set ratio through a dedicated injection system, and the muck discharge status and equipment parameters are monitored in real time to dynamically adjust the injection strategy.
In a shield tunnelling project on an urban metro extension line, the construction section passed through a thick layer of highly plastic clay. In the early stage, the cutterhead torque rose abnormally, the muck discharge outlet was frequently blocked, and the daily progress fell far behind. After the Chemi Tech dispersant solution was introduced and the three steps above were carried out, clay caking was significantly reduced and muck discharge became continuous and smooth. The cutterhead torque fell back to the normal range, the average daily tunnelling efficiency increased by about 30%, and the cutter inspection cycle was extended, restoring a stable overall construction rhythm. The project owner affirmed the treatment results.
Chemi Tech's shield tunnelling clay dispersant is designed to help you remove the construction obstacles caused by clay, keep shield equipment running smoothly, and let tunnel projects advance more efficiently and more economically.