Estimation of lateral displacement induced by jet grouting in clayey soils

Abstract

The installation of jet-grouted columns in soft ground can induce lateral displacement resulting from injection of a great amount of water and grout into the ground, which may then lead on to further significant effects. This paper presents an approach to estimate the lateral displacement due to the installation of a jet-grouted column in clayey soils. Assuming that the installation of a jet-grouted column is represented by the expansion of a cylindrical cavity with a uniform radial stress applied at the plastic–elastic interface in a half-plane, the analytical solution developed by Verruijt is adopted in this study to calculate the lateral displacements attributable to the expansion of the cylindrical cavity. An empirical equation that accounts for the jetting parameters (jetting pressure, flow rate of the fluid and rod withdrawal rate) and soil properties (soil type and its undrained shear strength) has been developed to determine the radius of the plastic zone. Three case histories analysed in this paper demonstrate that the proposed method can be used for estimation of the lateral displacement caused by installing jet-grouted columns in clayey soils, despite minor discrepancies from the group column installation case between the predicted and measured values. These minor discrepancies can most likely be attributed to the omission of the effect of installation sequence and rheological properties of the grout in the calculation.

Simple Method to Predict Ground Displacements Caused by Installing Horizontal Jet-Grouting Columns

“…It should be noted that the method in the previous publication of the authors [19] is developed for analyzing the vertical jet grouting cases, but the authors found that Shen et al 's method cannot be directly used to obtain a reasonable displacement prediction for the horizontal jet grouting cases in engineering practice. Thus, a new approach is developed in this paper to provide a reasonable displacement prediction for horizontal jet grouting cases.…”

“…Jet grouting is frequently used for the launching of shield machines or tunnel construction in complex geological conditions. Jet grouting technology is based on the injection of high velocity fluids through smalldiameter nozzles to erode the soil and mix it with injected grout to form a soil-cement column [16][17][18][19][20][21]. Based on the different methods of fluid injection, jet-grouting technology can be classified as (a) single fluid system (grout only), (b) double fluid system (grout + air), or (c) triple fluid system (water + grout + air) [22][23][24][25].…”

“…As jet grouting involves the injection of large volumes of water or grout into the soil, inevitable disturbance of the surrounding soil will occur, which may cause significant displacement of the ground [4,19,[32][33][34][35][36][37]. When jet-grouting columns are installed horizontally, the impact on the surrounding soil is mainly due to the vertical orientation of the jet, which is of great concern for geotechnical engineers.…”

Investigation of Collapsed Building Incidents on Soft Marine Deposit: Both from Social and Technical Perspectives

“…To sustainable urban development, geotechnical investigation, parameter selection, and structural design should be undertaken for such constructions. In future developments, before building construction, preventive measures such as geotechnical investigation and ground treatment, e.g., soil compaction, ground treatment, and piled foundation construction, may be necessary to improve the shearing resistance and stiffness of the existing ground [61,62]. Additionally, relevant regulations to prevent rooftop additions should be established to reduce potential damages to occupants in similar collapse events.…”

Vertical Shaft Support Improvement Studies by Strata Grouting at Aquifer Zone

“…However, the negative influence of the strata grouting on the shaft lining is obvious and large [27]. Moreover, due to the grouting process is in the soil layer, the effect of the injection pressure on the shaft lining depends on the actual formation conditions and the treatment effect cannot be guaranteed [28,29]. It is necessary to establish a new method for the failure treatment which has the effect of the strata grouting and not the negative influence.…”