When using an earth pressure balance shield (EPB) for tunneling, there are indeed some special things to pay attention to to ensure construction safety and efficiency. Here are some key points:

   1. Geological survey and analysis: Before construction, a detailed geological survey must be carried out to understand the geological conditions, including soil type, groundwater level, rock hardness, etc., to ensure the selection of the appropriate shield machine model and construction parameters.

   2. Soil compartment pressure control: Monitor the pressure in the soil compartment to maintain balance with the water and soil pressure of the excavation surface to avoid surface uplift or settlement.

   3. Tool management: Regularly check and replace the tool, especially in strata with high hard rock or gravel content, to ensure the cutting performance and structural strength of the cutterhead.

   4. Muck improvement: Select appropriate slag improvers according to geological conditions to ensure the fluidity and water-stopping properties of the slag for effective discharge.

   5. Synchronous grouting: Ensure the quality and quantity of grouting, fill the gap between the pipe segment and the stratum, and reduce stratum deformation.

   6. Equipment maintenance: formulate a strict maintenance plan, regularly inspect, maintain and repair the shield machine to ensure the normal operation of the equipment and reduce the failure rate.

   7. Construction monitoring: establish a complete monitoring system, monitor the surface settlement, tunnel axis deviation and other data in real time, and adjust the construction parameters in time.

   8. Emergency response plan: formulate a detailed emergency response plan to deal with possible emergencies such as water inrush, landslides or equipment failures to ensure construction safety.

   9. Personnel training: provide sufficient technical training and safety education to improve the professional quality and emergency response capabilities of operators.

   Following the above precautions can maximize the safety and efficiency of EPB shield machine construction while reducing the impact on the environment and surrounding facilities.