pfc真三轴伺服加载命令流，加载方法借鉴于《颗粒流（PFC5.0）数值模拟技术及应用》，但其内容已做大部分修改，模型与接触的命令流为原创，加载命令也做了一定修改。(pfc true three-axis servo loading command stream, the loading method is borrowed from "Particle Flow (PFC5.0) Numerical Simulation Technology and Application", but most of its content has been modified, the command stream of the model and contact is original, and the loading command is also done Must be revised.)