Strength improvement of soft soil using silica fume and pedel soil: A laboratory study for sustainable infrastructure

¹ Magister of Applied Infrastructure Engineering Study Program, Department of Civil Engineering, Bandung State Polytechnic, 40599, Bandung, Indonesia
² Department of Civil Engineering, National Institute Technology, Bandung, Indonesia
³ Department of Civil Engineering, Institute Polytechnic of Betone, Manufahi, Timor Leste

^* Corresponding author: rifka.ananda.mtri24@polban.ac.id.

Abstract

Improving soil quality is essential for sustainable infrastructure development, especially in transportation projects. Low soil bearing capacity often leads to structural failures, necessitating stabilization methods. However, conventional stabilizers such as cement and lime are environmentally unfriendly, contributing up to 8% of Global CO2 emissions. This concern encourages the exploration of sustainable alternatives. This Study investigates the use of pedel soil and silica fume as a ecofriendly stabilizing materials to improve soil strength. Laboratory test evaluated unconfined compressive strength (UCS) and shear strength parameters. The results showed that a mixtures containing 9% pedel soil and 7,5% silica fume achieved optimum performance, with compressive strength increasing from 0,422 to 1,975 kg/cm², cohesion and friction angle improving from 0,291 kg/cm² and 8,890⁰ to 0,848 kg/cm² and 13,422⁰ respectively. These findings demonstrate that natural and sustainable materials can effectively enhance soil stability. Soil improvement through stabilization is thus a vital component of civil engineering for resilient infrastructure development.