TurboJET - Deep Soil Mixing (DSM)
TurboJET is a highly
effective method of deep soil mixing (DSM)
which was recently introduced to New Zealand by Hiway
GeoTechnical.
TurboJET is a hybrid system, utilising both high pressure grout injection and mechanical mixing. This process efficiently mixes soil and grout, producing homogenous, uniform high strength columns.
Hiway GeoTechnical introduced the TurboJET system which was selected for its performance, cost effectiveness, versatility and wide range of potential applications within New Zealand. TurboJET extends the capability and success of the COLMIX based DSM system.
"We can now continue to lead the way in our field, providing our valued clients with a new level of technology, service and performance."
Description
TurboJET represents the latest development of "wet" grout DSM. TurboJET is a hybrid system incorporating high pressure "jet" cutting and mechanical mixing to provide a highly efficient method of soil mixing.
Grout is injected at high pressure through a series of outlet nozzles blending soil as the mixing tool advances. High pressure cutting is effective in most soil types including problematic cohesive plastic clays.
The mechanical mixing of grout and soil is achieved using a mixing tool featuring cutting teeth, blades and a mixing head. The type and configuration of tool is selected for project specific requirements and soil types.
TurboJET columns are 600mm diameter with a strength up to several MPa depending on soil types and binder design. Column depths of up to 20 metres are achievable.
Implementation
The type of binder and application rate is selected depending on soil type and project requirements. Grout mix selection is based on geotechnical site investigations, laboratory testing and field trials and experience.
Grout is batched using an automated GM14 grout batching plant featuring automated electronic weighing of binders, accurately controlled water injection and a series of high sheer mixer and agitator tanks.
Grout is delivered to the mixing tool using a high pressure triplex piston pump capable of delivering pressure up to 500 Bar (7000 PSI). Grout pressure is fully variable, being selected depending on the soil types and the column mix design.
TurboJET provides a number of advantages compared with conventional methods:
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Cost
effective -
Fast installation time
-
High degree of Quality Control
-
Proven field performance
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Rapid design build project delivery
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No vibration
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Minimal soil displacement
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Depth capability (20+ meters)
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Application in wide range of material types
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Proven technology
-
Uniform and homogeneous
Quality Assurance
A high degree of quality control is achieved through the use of an onboard computer which provides monitoring and data capture of all drilling and grout parameters in real time.
Data downloading and processing enables analysis of individual columns to ensure that design parameters are achieved.
Comprehensive sampling, testing and post construction testing is implemented to validate design strengths and ensure that the design criteria is met.
Application
Hiway GeoTechnical has completed numerous DSM projects, including:
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Road slip repair
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Ground improvement for embankments and civil construction projects
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Building foundations
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Liquefaction control and settlement prevention
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Shear key construction and earth dam foundations
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Retaining Walls
The majority of projects have been design build contracts. Innovative design is achieved using Plaxis 3D finite element analysis and a range of supporting geotechnical design software.
Hiway Stabilizers has twice won the Transit NZ Road Innovation Award for DSM projects. The company has also published and presented many papers at local and international geotechnical conferences and are recognised leaders in this specialised field and a member of the International Deep Soil Mixing Organisation.
TurboJET installing DSM columns for Clive Wastewater Treatment Plant
Please click on the link if you would like to view the Technical Paper on the Clive Waste Water Treatment Plant.
