Under conditions of high alkali cement, reactive aggregates, and water presence, Alkali-Silica Reaction (ASR) can cause expansion and cracking within concrete. If left unmitigated, ASR can cause serious deterioration and damage to concrete structures over time. The best way to mitigate ASR is to avoid it altogether by using non-reactive aggregates. ATL uses standardized test methods for determining the potential reactivity of aggregates.
Do you have a structure that is exhibiting signs of distress, such as spalling concrete with exposed and corroding reinforcing steel? There can be several factors leading to this condition. In this article, we will discuss carbonation and its effect on concrete and embedded steel over time. We will also highlight common methods for evaluating concrete that can prove helpful in determining mitigation and repair strategies for a structure.
Concrete is a common building and structural component that can be impacted by exposure to fire. Concrete is fairly heat resistant to approximately 500 to 600 °F. Once concrete reaches that range of temperature or beyond, damage can occur. Rapid cooling, which can occur during firefighting activities, can also adversely affect the concrete by creating thermal shock. Fire-exposed concrete can be evaluated by several methods: including visual examination of cracks, spalls, or color changes; extraction of core samples to evaluate concrete strength or perform petrographic analysis for microscopic evidence of damage; and/or evaluation through nondestructive means such as ultrasonic pulse velocity (UPV) testing, discussed further below.
In response to growing demand from clients and the concrete/aggregate producer industry throughout the US and abroad, ATL has expanded our concrete and aggregate laboratory testing capabilities to include Rapid Freeze Thaw and Alkali Reactivity Testing.
Concrete (derived from the Latin word “concretus”, which means “to grow together”) is the most widely-used and most manufactured product, by volume, in the world today. It is a complex, man-made mixture of naturally-occurring materials and air first developed and utilized by the Romans as a building material (opus caementicium) over 2,200 years ago.
Understanding the thermal properties of the materials used in underground power systems is crucial for their design.