Fall cone test on biopolymer-treated clay

Cheng Zhanbo,Ni Jing,Ding Haotian,Geng Xueyu,R Cardoso,C Jommi,E Romero

doi:10.1051/e3sconf/202019503041

Cheng Zhanbo, Ni Jing + Show 5 more

Open Access

https://doi.org/10.1051/e3sconf/202019503041

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Abstract

Fall cone tests were conducted to evaluate the consistency variations of clay soils treated with six types of biopolymers, e.g. carrageenan kappa gum (KG), locust bean gum (BG), xanthan gum (XG), agar gum (AG), guar gum (GG) and sodium alginate (SA) at various concentrations (e.g. between 0.1% to 5% biopolymer to soil mass ratio). The dependences of shear viscosity on water content, and undrained shear strength on water content were established. The results indicated that KG and SA increased the liquid limit (LL) of treated soils after the biopolymer content exceeded a certain limit (e.g. 0.5%), BG and GG contributed to a peak point in LL at biopolymer concentration of 1% to 2%, while XG and AG almost did not change the LL at all. The plastic limit (PL) was about 25% to 50% of the LL, leading to a trend of plasticity index (PI) similar to liquid limit. In order to further simplify the testing procedure and get the Atterberg limits for biopolymer-treated soil, one-point method was adopted.

Highlights

Civil engineering infrastructures are commonly constructed on weak or loose soils that requires improvement to resist applied loads [1,2,3,4]
Have an insight knowledge of soil consistency is important in understanding particle aggregation and water absorption characteristics of biopolymer treated soils for geotechnical applications
Nugent explained active nanoscale interactions between soil particles, cations, biopolymer and water from five different types of biopolymer treated soil to determine the liquid limit of the treated soil (e.g. xanthan gum (XG), guar gum (GG)) [7]

Summary

Introduction

Civil engineering infrastructures are commonly constructed on weak or loose soils that requires improvement to resist applied loads [1,2,3,4]. Have an insight knowledge of soil consistency is important in understanding particle aggregation and water absorption characteristics of biopolymer treated soils for geotechnical applications. Chang explored the influence of pore-fluid variation on Atterberg limits of XG treated soils. The soil consistency of biopolymer treated clay with various biopolymer types and a wide range of biopolymer concentrations should be further comprehensively explored to meet the gap for geotechnical engineering application. Six typically biopolymers extracted from plants, metastatic products of microorganism, or cell walls of algae which have been widely used in certain fields (e.g. food, paint, oil exploration) and are the potential materials in the application of civil engineering infrastructures, were adopted to treat soil with a wide concentrations range from 0.1% to 5%. The general results about Atterberg limits of biopolymers treated soil were investigated by using fall cone test

Materials

Results of Atterberg limits

Kaolinite-biopolymer mixture preparation

Mechanism

Fall cone test

One-point method determining liquid limit