Investigating effects of application of silica fume and sbs as modifiers to reduce moisture sensitivity of asphalt concrete mixture

Abstract EN

Moisture damage is one of the most common reasons for the premature deterioration of Hot Mix Asphalt (HMA) pavements.

Over the years, extensive research has been carried out by scientists and engineers on this subject; however, pavements still succumb to early failure from infiltrating moisture.

A very popular method of minimizing the moisture susceptibility of asphalt pavements is by the use of anti-stripping agents.

These additives are chemical substances that alter the physicochemical properties of the asphalt by making it more hydrophobic.

This study focuses on the effect of anti-stripping agents on the moisture susceptibility of asphalt Concrete mixture.

The anti-stripping agents used were (SBS, Silica fume, and SBS with Silica fume) with different percentages.

The laboratory tests include indirect tensile strength test, Marshall and retained Marshall Stability test (RMS) and double punching shear strength test.

The test results show that the asphalt mixtures modified by (Silica fume+ SBS) have highest values in Marshall Stability, RMS and it increased the moisture and stripping resistance.

However, using (3% Silica fume+3% SBS) has the best effect on Marshall Stability, TSR value and stripping resistance.

While (4% Silica fume+3% SBS) has the best effect on RMS value.

From the experimental results, it is observed that the addition of anti-stripping agents had a significant positive influence on the results of the test properties being evaluated in each Moisture damage is one of the most common reasons for the premature deterioration of Hot Mix Asphalt (HMA) pavements.

Over the years, extensive research has been carried out by scientists and engineers on this subject; however, pavements still succumb to early failure from infiltrating moisture.

A very popular method of minimizing the moisture susceptibility of asphalt pavements is by the use of anti-stripping agents.

These additives are chemical substances that alter the physicochemical properties of the asphalt by making it more hydrophobic.

This study focuses on the effect of anti-stripping agents on the moisture susceptibility of asphalt Concrete mixture.

The anti-stripping agents used were (SBS, Silica fume, and SBS with Silica fume) with different percentages.

The laboratory tests include indirect tensile strength test, Marshall and retained Marshall Stability test (RMS) and double punching shear strength test.

The test results show that the asphalt mixtures modified by (Silica fume+ SBS) have highest values in Marshall Stability, RMS and it increased the moisture and stripping resistance.

However, using (3% Silica fume+3% SBS) has the best effect on Marshall Stability, TSR value and stripping resistance.

While (4% Silica fume+3% SBS) has the best effect on RMS value.

From the experimental results, it is observed that the addition of anti-stripping agents had a significant positive influence on the results of the test properties being evaluated in each test.