摘要
For rotary drilling bored grouting pile construction in thick clay, silt and sand layer, borehole collapsing, drill rod burying, drill rod sticking, diameter shrinking and pile breaking often occur because of technical defects. On the premise of analysis on the mechanism in which low viscosity, fluid loss reduction and speed-up cuttings precipitation were solved, the formula of FCLS LV-CMC mud with low viscosity, high-level fluid loss reduction and anti-precipitation was put forward.