ATT Study Guide 2026
Everything you need to pass the ATT exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 ATT Exam Format at a Glance
📚 ATT Topics to Study (21)
✍️ Sample ATT Questions & Answers
1. How should a field sample be reduced to testing size?
Mechanical splitting or quartering methods must be used to reduce the sample without bias.
2. Per ASTM C117, what must be done with any material retained on the No. 200 sieve after washing?
Material retained on the No. 200 sieve during washing must be returned to the main sample so that the total post-wash dry mass accurately represents all particles coarser than 75 µm.
3. Which of the following best describes 'decanting' in the context of ASTM C117?
Decanting means carefully pouring the turbid wash water (carrying suspended fines) over the No. 200 sieve while keeping the coarse aggregate in the container.
4. Which test best evaluates the presence of plastic fines (clay minerals) in fine aggregate that could reduce concrete durability?
The sand equivalent test (ASTM D2419) is specifically designed to measure the relative proportion of clay-like plastic fines in fine aggregate.
5. In ASTM C117 (material finer than No. 200), after washing the aggregate is dried to constant mass at what temperature?
After washing, the aggregate is dried to constant mass at 110 ± 5°C in accordance with ASTM C117.
6. The percentage of material finer than the No. 200 sieve by washing is calculated using which formula?
The formula (A − B) / A × 100 gives the percent passing No. 200, where A is the original dry mass and B is the dry mass after washing.