METHOD FOR ESTIMATING CONCENTRATION OF GROUTING AGENT

To provide a method for estimating a concentration of a grouting agent which enables estimation of concentration of a grouting agent before and after decomposition of the grouting agent.SOLUTION: A method for estimating a concentration of a grouting agent comprises the steps of: adding to a grouting liquid, a grouting agent decomposed in the ground 10, and an index agent having characteristic which changes in the ground similar to the grouting agent, exhibiting the same behavior as the grouting agent before the decomposition of the grouting agent before the change of the characteristic in the ground, and exhibiting the same behavior as the grouting agent after the decomposition of the grouting agent after the change of the characteristic; injecting the grouting liquid into the ground; collecting underground water from an arbitrary point in the ground after injection of the grouting liquid into the ground; measuring a concentration of the index agent before the change and a concentration of the index agent after the change in the collected underground water; and estimating the concentration of the grouting agent before the decomposition from the concentration of the index agent before the change, and estimating the concentration of the grouting agent after the decomposition from the concentration of the index agent after the change.SELECTED DRAWING: Figure 1B 【課題】分解前後の注入剤の濃度をそれぞれ推定できる注入剤の濃度推定方法を提供する。【解決手段】注入剤の濃度推定方法は、地盤１０中で分解される注入剤と、地盤中で注入剤と同様に特性が変化すると共に、地盤中において、変化前に分解前の注入剤と同様の挙動を示し、変化後に分解後の注入剤と同様の挙動を示す指標剤とを、注入液に添加する工程と、注入液を地盤中に注入する工程と、注入液を地盤中に注入後に、地盤における任意の観測点から地下水を採水する工程と、採水された地下水における変化前の指標剤の濃度と変化後の指標剤の濃度とを測定する工程と、変化前の指標剤の濃度から分解前の注入剤の濃度を推定し、変化後の指標剤の濃度から分解後の注入剤の濃度を推定する工程と、を備えている。【選択図】図１Ｂ