Concept of Curtain Grouting Evaluation

Grouting work, when conducted under a procedure compatible with ground conditions, produces a ground response that can be measured. The ground response is an index of the change caused by the grout injections and can be used to evaluate results. The unit take or quotient of the grout consumed, divided by the linear feet of hole required to make the injection, provides the valid basis for evaluation. When unit takes are plotted against hole spacing, the curves establish trends that can be used to evaluate the work for effectiveness of the grout curtain. A variety of plottings on the available coordinate scales set patterns that can be used to control the operation. Grouting work at nine large projects illustrates this basic concept.