URECA

Undergraduate Research Experience on CAmpus

www.ntu.edu.sg/ureca

Category: 02 Student: Kevin Janiardy Project ID: CEE14013 School of Civil and Environmental Engineering

Project Title: Effect of Basic Soil Properties on Hydraulic Anisotropy of Homogeneous Soil Supervisor: Prof. Harianto Rahardjo Collaborator: Mr. Priono

Background Hydraulic anisotropy is expected to greatly influence fluid flow in soil. Soil with high anisotropy will have hydraulic flow

significantly faster in parallel direction than in perpendicular direction of layering. However, factors contributing to high

hydraulic anisotropy in homogeneous soil have not been thoroughly quantified. Presence of mica, which has platy-shaped

particles, is expected to affect the hydraulic anisotropy of soil and is explored in this research.

Objective To study the behavior of hydraulic anisotropy on soil having different percentage of mica.

BASIC SOIL PROPERTIES +10% Mica +25% Mica

Liquid Limit, LL (%) 50.5 48.2

Plastic Limit, PL (%) 32.3 32.2

Plasticity Index, Ip (%) 18.3 16.0

Specific Gravity, Gs 2.65 2.69

GSD – Coarse-grained (%) 54.8 63.7

GSD – Fine-grained (%) 45.2 36.3

Classification System (USCS) SM SM

Discussions and Ongoing Works Higher mica content in soil shifted the compaction curve downwards to the right, indicating the decrease soil density at a

given water content. Saturated permeability test on specimen of +25% mica content shows that the ratio of VL to HL

permeability, i.e. hydraulic anisotropy is 3.69 (significant). In the ongoing test of +10% mica content, it is expected that the

specimen has a higher hydraulic anisotropy. The other ongoing experiments are Soil-Water Characteristic Curve Test to

observe hydraulic anisotropy behavior of the specimens throughout unsaturated zone and large scale hydraulic anisotropy

experiments.

Ottawa Sand

Mica

Kaolin

Soil Mixture

Results

Compaction Curve Permeability Test (25% Mica)

Specimens