Abstract:Based on the formation mechanism of high-pressure rotary jet piles and the current market demand for large diameter pile construction, a spray nozzle has been developed to cope with new processes and methods and eliminate the problems with conventional rotary jet such as small pile diameter, environmental pollution from mud discharge. Analysis of the actual working condition of the nozzle under the ground shows that the newly developed 11-tube nozzle has the characteristics of in-situ pressure detection, mud discharge through special channels, large thru-bore diameter of the slurry pipe, etc., which can realize large pile diameter construction, uniform mud recovery and avoid disturbance to surrounding buildings.