The document discusses aggregate testing services, emphasizing the importance of minimum strength values and specifications for quality materials in construction. It covers the alkali-aggregate reaction that can weaken concrete, as well as the flakiness and crushing value assessments of aggregates. Contact information for Sigma Test & Research Centre is also provided, including phone numbers, email, and website.

1. Aggregate Testing Services

2. About
Aggregate Testing Services
• All aggregate is required to meet a minimum strength valve,
as defined by the 10% value test. This and other specifications
ensure that only the highest quality materials are being used
on construction projects.
• Alkali-aggregate reaction is a term mainly referring to a
reaction which occurs over time in concrete between the
highly alkaline cement paste and non-crystalline silicon
dioxide, which is found in many common aggregates. This
reaction can cause expansion of the altered aggregate,
leading to spalling and loss of strength of the concrete.

3. • Flakiness and Elongation Index:
Flakey is the term applied to aggregate or chippings that are flat and thin
with respect to their length or width, Aggregate particles are said to be
flakey when their thickness is less than 0.6 of their mean size. The
flakiness index is found by expressing the weight of the flakey aggregate as
a percentage of the aggregate tested.
• Crushing Value:
The Aggregate Crushing Value offers a related measure of the resistance of
an average to crushing under a compressive load that is gradually applied.

4. Sigma Test & Research Centre
Address: BA-15, Mangolpuri Industrial Area Phase-
II Delhi-110034(India)
Ph No: +91-11-49491414/15
Fax: +91-11-4385 2040
Email: info@sigmatest.org
Email: rahul@sigmatest.org
Website: www.sigmatest.org,
http://www.sigmatest.org/Aggregate-Testing.html
Contact person: Mr. Rahul Gupta
Mobile: +91- 9811565000