Deep mixing method for the construction of earth and water retaining walls

  • Nicolas Denies Belgian Building Research Institute, Geotechnical Division
  • Noël Huybrechts Belgian Building Research Institute, Geotechnical Division

Abstract

In the deep mixing method, the ground is mechanically mixed in place while a binder, often based on cement, is injected. After hardening of the soil-cement mixture, called soil mix material, soil mix elements are formed in the ground. Originally known as a ground improvement technique, the deep mixing is more and more applied for the construction of earth-water retaining structures within the framework of excavation works.


After a short introduction to the execution aspects of the method, the authors discuss the hydro-mechanical properties of the soil mix material mainly based on the results of the BBRI Soil Mix project (2009-2013). A design approach dedicated to the soil mix retaining walls and developed in collaboration with the SBRCURnet is then presented. In this methodology, which is in line with the structural Eurocodes, design rules are adapted to the functions of the soil mix wall (earth-water retaining, bearing and cut-off functions) including the temporary or permanent character of the application. Based on the result of large-scale bending tests, the interaction between the soil mix material and the steel reinforcement is considered in the calculations allowing a reduction of the steel section between 10 and 40 %.

Author Biographies

Nicolas Denies, Belgian Building Research Institute, Geotechnical Division

Dr Ir Nicolas Denies is Deputy Head of laboratory in the Geotechnical Division of the Belgian Building Research Institute (BBRI). His core business consists in the deep mixing technology, the ground improvement works and the geotechnical monitoring. He is also involved in the testing of piles, anchors, jet grouting columns and micro-piles.

Nicolas Denies is member of the Belgian Society for Soil Mechanics and he is the Secretary of the ISSMGE Technical Committee 211 for Ground Improvement.

Noël Huybrechts, Belgian Building Research Institute, Geotechnical Division
Prof Ir Noël Huybrechts is Head of Geotechnical Division of the Belgian Building Research Institute (BBRI). His core business mainly consists in the foundation technologies, the ground improvement works and the geotechnical monitoring. He also presents a large experience in the testing of piles, anchors, jet grouting columns, micro-piles and various geotechnical structures. Noël Huybrechts is member of the Belgian Society for Soil Mechanics and he is the Chairman of the ISSMGE Technical Committee 211 for Ground Improvement. Noël Huybrechts is professor of soil mechanics and geotechnics at the university of KU Leuven.
Published
2017-09-21
How to Cite
DENIES, Nicolas; HUYBRECHTS, Noël. Deep mixing method for the construction of earth and water retaining walls. RILEM Technical Letters, [S.l.], v. 2, p. 1-9, sep. 2017. ISSN 2518-0231. Available at: <https://letters.rilem.net/index.php/rilem/article/view/27>. Date accessed: 22 oct. 2017. doi: https://doi.org/10.21809/rilemtechlett.2017.27.
Section
Letters

Keywords

Deep mixing, soil mix retaining wall, mechanical characterization, design approach