ACI Aggregate Base Testing Technician – Sampling, Reduction, and Soil Classification Exam Questions

Description: This document contains verified exam questions for ACI Aggregate Base Testing Technician certification. Topics include aggregate sampling methods, sample reduction techniques, soil classification tests, moisture and liquid limit testing, and specific gravity procedures. It emphasizes ASTM standards and correct procedures to ensure representative and accurate test results. Testing - answerSampling should be done very carefully because it is as important as ____________. Conveyer belts Transport units Roadways Stockpiles - answerWhat are the four sources from which field samples can be obtained? contaminated, damaged - answerSampling containers for aggregate samples should be made so that the contents will not be lost, _____ or _____. Nonrepresentative sample - answerNot using correct procedures for reducing samples to testing size can result in a _____. False - answerT or F Generally, small samples are most representative of the total supply. True - answerT or F There are some instances in which differences between test samples can't be Page1 avoided. Laws of chance - answerWhat determines whether large-size particles are equally distributed among test samples that have been reduced? Method A, mechanical splitter - answerWhich method of reducing a sample must be used with fine, dry aggregate? Moisten the sample - answerWhat must be done to the sample if method B or C is used? Dry the sample - answerWhat do you do if the sample is wet and Method A is to be used? Coarse aggregate, or mixtures of coarse and fine aggregate - answerMethod C, miniature stockpiling, cannot be used for which type of aggregate? Method A - answerWhich method involves the use of chutes, holding receptacles, and hoppers or straight-edged pans? 8 - answerSample splitters must have how many equal width chutes for coarse aggregate? 12 - answerSample splitters must have how many equal width chutes for fine aggregate? conical pile - answerIn Methods B and C the sample is shoveled into a ____ before it is flattened and divided. Canvas blanket or tear resistant tarp - answerWhen using Method B, what is an alternate surface that can be used when reducing the sample? diagonally opposite - answerWhen quartering a sample, retain two _________ quarters and reject the other two. 5, random - answerIn miniature stockpile sampling, obtain the sample by selecting at least ____ increments of material from ____ locations in the stockpile. 60*C/140*F - answerThe drying apparatus used for dry preparation of a sample is any suitable device capable of Page2 drying samples at a temperature not exceeding _____. representative, fines - answerA suitable sample splitter is one capable of obtaining ____ portions of the sample without appreciable loss of ____. 110, 60 - answerFor particle size analysis, material passing a 2.00mm (No. 10) sieve is required in amounts equal to approximately ___ g for sandy soils and approximately ___g for silty or clayey soils. 25, 10 - answerFor specific gravity, material passing a 2.00mm (10) sieve is requires in amounts of at least ____g when the volumetric flask is used and at least ____g when the stoppered bottle is used. 2.00mm (No. 10), Two - answerFor the physical test, the remaining portion of the material passing the _____ sieve shall be separated into ____ parts by means of a 0.425mm (40) sieve. Pulverizing operation - answerFor the physical test, if the sample contains brittle particles such as flakes of mica, fragments of seashells, etc, the ____________ shall be done carefully to free the finer material that adheres to the coarse particles. The liquid limit of a soil - answerWhat is defined as he water content at which the soil passes from a plastic to a liquid? corrosion, mass, disintegration - answer(LL) suitable containers should be made of material resistant to ____ and not subject to