METHOD TO DETERMINE QUANTITY OF CEMENT IN SOIL-CEMENT MATERIAL OF STRUCTURE Russian patent published in 2014 - IPC E02D3/12 G01N27/22 

FIELD: construction.

SUBSTANCE: invention relates to technology of construction and may be used to determine quantity of cement in soil-cement material in creation of building structures by means of jet cementing. The method to determine quantity of cement in the soil-cement material of the structure in development of building structures by means of jet cementing consists in addition of a powdery indicator into the cement mortar injected into a well. Such powdery indicator may be powder graphite, fineness of grinding of which is not below fineness of cement grinding. Weight ratio of graphite powder makes 1-10% of cement weight. During realisation of the method they first measure electric conductivity of the injected cement mortar, then electric conductivity of the soil and cement pulp discharged from the well is measured, and the quantity of cement in the soil-cement material of the structure is determined as difference between the cement quantity in the cement mortar and the quantity of cement in the pulp. The quantity of cement in the pulp is calculated in accordance with the following formula: $$m_{cn}=\frac{m_c{\lambda }_n}{{\lambda }_c},$$ where m_cn - quantity of cement in the pulp; m_c - quantity of cement in the cement mortar; λ_n - value of pulp electric conductivity; λ_c - value of cement mortar electric conductivity.

EFFECT: higher efficiency of the method.