The jet grouting technique was originally initiated in the UK and progressively developed following the needs for larger geometries, ease of implementation, economic rationality, and better mechanical properties. This paper presents a comprehensive review of the development and practice of jet grouting through some fundamental concepts and relevant case studies. Subsequently, a laboratory testing program is performed to investigate the factors affecting the efficacy of the twin grouting system. The principal objective of this study is to define the suitable conditions for the jet grouting efficacy regarding economic rationality as well as quality control. For the first phase, a particular emphasis is placed on the properties of jet columns, site geological conditions, implementation methods, and the justification of each selected treatment option, while the second phase mainly focuses on the unconfined compressive strength (UCS) tests. It follows that the mono-fluid jet grouting system presents a valuable flexibility in dealing with complex configurations; yet, the double- and triple-fluid systems are more indicated for cases of mass treatments for which large portions of space must be treated and overlapping is fundamentally important for the reliability of the treatment. Furthermore, it was established that the efficacy of the twin-jet method primarily relies on the proper adequacy of some critical parameters, namely, the cement content, the water-cement ratio, and cement slurry-water glass ratio. In spite of some uncertainties inherently related to the technique, the UCS test represents the quintessential laboratory index for evaluating the mechanical properties of grouted elements, deriving jet grouting efficacy and the economics of jet grouts.

A review of jet grouting practice and development

This paper discusses recent advances in the implementation of horizontal jet grouting (HJG) for the ground improvement of soft soil. Field trials of HJG were undertaken in soft soils in Shanghai, and the research is reported and discussed in this paper. Particular emphasis was placed to study the hardening process in non-cohesive soils. The recent innovations in HJG were found to arise principally from challenges in implementing jet grouting in sandy soil and also from the harmful effects on the surrounding caused by the traditional implementation process. Accordingly, the recently developed composite jet pipe, pressure-control jet grouting and control discharge horizontal jet grouting methods have been successfully implemented to mitigate the ground upheaval and displacements. Moreover, the characteristics of the jet grout columns obtained with these methods were found as a rule to perform beyond expectations. It was also found that the newly developed horizontal twin-jet grouting technology, underpinned by an instant-solidification mechanism, overcame challenging issues such as mixing uniformity, loss of admixture and hardening. The characteristics of hardening in particular have initiated new perspectives, given that a better acquaintance of the mechanisms of hardening and ground displacements is bound to play an important role in the future practice and the development of the jet grouting process. Interestingly, smoothed particle hydrodynamics technique was found to be suited for modeling jet grouting mechanisms.

Recent Advances in Horizontal Jet Grouting (HJG): An Overview

Numerical simulation of dynamic water grouting using quick-setting slurry in rock fracture: the Sequential Diffusion and Solidification (SDS) method

Effects of jet grouting slabs on responses for deep braced excavations

Analysis of lateral response of existing single pile caused by penetration of adjacent pile in undrained clay

High pressure jet-grouting column installation effect in soft soil: Theoretical model and field application

A general semi-analytical solution for consolidation around an expanded cylindrical and spherical cavity in modified Cam Clay

This work presents an analysis of the influence of stress anisotropy on cylindrical cavity expansions in an undrained elastic-perfectly plastic soil. This problem was formulated by assuming a large strain in both the elastic and plastic zones around the cavity and a plain strain condition during the cavity expansion process. The solutions for the limit pressure, stress, and excess pore pressure were obtained by introducing the anisotropic initial stress coefficient K0 into the conventional cylindrical cavity expansion method. The proposed solutions were then used to interpret the piezocone penetration test, and the suitability of the solutions was verified by comparing the prediction with the piezocone penetration test data. Subsequently, parametric studies were carried out to investigate the influence of stress anisotropy on the stress, excess pores pressure distributions around an expanding cylindrical cavity, and limit pressure. The results show that the proposed cylindrical cavity expansion method under stress anisotropy is suitable and can be used to investigate the piezocone cone test. The present work improves upon the conventional theoretical framework of cavity expansion and can be applied to the determination of the stresses around axially loaded piles and around in-situ testing devices such as penetrometers.

Influence of stress anisotropy on the cylindrical cavity expansion in undrained elastic-perfectly plastic soil

The invention provides a discrete material core expansion concrete pile and a construction method thereof. The discrete material core expansion concrete pile comprises a concrete semi-hollow pile and a discrete material pile core. An inner cavity of the concrete semi-hollow pile is filled with the discrete material pile core. The construction method of the discrete material core expansion concrete pile comprises the steps of hole forming, steel pipe pile die downward pressing, pile body periphery concrete pouring, pile body center discrete material throwing, vibration pile die pulling, pulp supplementing and pile forming and the like. The discrete material of the center of a pile body of the discrete material core expansion concrete pile is good in integrity and high in strength. The pile body is high in overall bearing force and large in rigidity. The construction cost is low, and low carbon and environment friendliness are achieved. The discrete material core expansion concrete pile and the construction method thereof can be widely applied to the foundation project.

Yahui Zha

Papers

High pressure jet-grouting column installation effect in soft soil: Theoretical model and field application

A general semi-analytical solution for consolidation around an expanded cylindrical and spherical cavity in modified Cam Clay

Influence of stress anisotropy on the cylindrical cavity expansion in undrained elastic-perfectly plastic soil

Discrete material core expansion concrete pile and construction method thereof