基于PLC的预应力智能张拉系统研究

Research on the prestressed intelligent tensioning system based on PLC

预应力筋张拉是预应力施工中的重要环节,针对传统预应力张拉应用中存在的问题,如人工测量误差较大、两端张拉同步率低、钢绞线测量准确率低、钢绞线的伸长值和张拉预应力难以实现同步控制等。提出了基于PLC的预应力智能张拉系统的研究。通过触摸屏和PLC组合方式控制千斤顶和油泵实现张拉,在整个张拉控制中以钢绞线的伸长量为校核量、以力值为控制对象,将采集传感器实时数据测量反馈到控制系统,控制系统根据相应的指令控制来改变反馈闭环液压系统的输入电流信号调整预应力构件两端张拉速度,进而实现钢绞线伸长值和预应张拉力的精确控制,保证张拉精度在2%的范围内,满足预应力工程应用的需求。

Aiming at the problems existing in the application of traditional prestressed tension,such as large manual measurement error,low synchronization rate at both ends,low accuracy of steel strand measurement,etc. The research of prestressed intelligent tensioning system based on PLC is carried out. Through the combination of touch screen and PLC,jack and oil pump are tensioned. In the whole tension control,taking the elongation of steel strand as the check measurement and the force value as the control object,the sensor real-time data is collected and fed back to the control system. According to the corresponding command control,the control system changes the input current signal of the feedback closed loop hydraulic system,and adjusts the tension speed at the two ends of the prestressed component. It realizes the precise control of the elongation value and pretension force of the steel strand,and ensures that the tension accuracy is within 2%,which meets the needs of prestressed engineering application.