ASTM C172: Standard Practice for Sampling Freshly Mixed Concrete

Updated on January 17, 2019
Lissa Clason profile image

Melissa has a bachelor's degree in geology, and is an ACI-certified field and lab technician at Froehling and Robertson.

Significance and Use of ASTM C172

ASTM C172 gives the requirements and procedures for sampling concrete out of different mixers and receptacles used in the making and moving of concrete. It is important to sample concrete in a way that gives you a portion of concrete that is representative of the entire batch, so that the cylinders you make are just like what's being used in the building that you're working on.

There are many different ways to mix and pour concrete, and this guide will teach you how to sample from all types of containers, from small stationary mixers that batch on site to large concrete trucks that pump concrete down a chute. In all cases, the time between receiving the first and last parts of the sample should not go over 15 minutes. Also, if you are making cylinders, you need to start molding them within 15 minutes after you have mixed the composite sample, and your sample should be at least 1 cubic foot in volume. Whatever container you use to collect the concrete must have a nonabsorbent surface.

When sampling from a truck mixer, you must take your sample from the middle portion of the batch.
When sampling from a truck mixer, you must take your sample from the middle portion of the batch.

ASTM C172 Procedure

Sampling From Stationary Mixers

Take two or more portions at regularly spaced intervals during the discharge of the middle portion of the batch, and mix them up into one composite sample with a shovel. No samples should be taken before 10% or after 90% of the batch has been discharged. To sample the concrete, pass the container through the discharge stream, or completely move the discharge stream into the sample container. If the concrete is coming out too quickly to send the stream entirely into the container, discharge the stream into a large container that could hold the entire batch, and then sample from that container. Restricting the flow of concrete out of the mixer could cause the concrete to separate into its components, so do not stop the concrete from flowing out.

Sampling From Paving Mixers

Sample the concrete after the paving mixer has discharged, not during the discharge like with other methods. Take your samples from at least five different portions of the pile, and then mix them up into one composite sample. Try to avoid contaminating the concrete with the subgrade material, especially prolonged contact with subgrade material that can absorb a lot of moisture, like clay. To avoid this, you can place containers on top of the subgrade and catch the concrete in them. In some cases you will have to support the containers so that they don't spill. They must be big enough to hold a representative sample of the concrete.

Sampling From Revolving Drum Truck Mixers

Sample the concrete by collecting two or more portions of concrete at regular intervals during the discharge of the middle part of the batch. Take these samples within a 15 minute period, and mix them up into one composite sample. Do not take your samples until all water has been added to the mixer, and also do not get your samples from the first 10% and last 10% of the batch. You should sample it by either diverting the entire stream into your container, or by passing your container through the stream at regular intervals. The rate of discharge of the batch should match the rate of revolution of the drum.

Sampling From Open Top Containers

For open top containers, you are allowed to take samples of the concrete by any of the previous three procedures. Choose the method that fits the situation the best.

Procedure for Concrete With Large Maximum Size Aggregates

When the concrete you are sampling has aggregate in it that's larger than the appropriate size for the molds or equipment you're using, you will need to run most of your sample through a sieve to take out the extra large aggregate, and perform a unit weight test on a small portion of the concrete with the large aggregate included.

Additional Equipment Required

  • A sieve of the suitable size to remove the unwanted large aggregate
  • A container of suitable size with a nonabsorbent surface
  • A shovel to mix the composite sample
  • Rubber gloves
  • A concrete scoop that can hold a representative scoop of the concrete

Wet Sieving Procedure

1. After you sample the concrete, pass a scoop of concrete over your sieve. Place only enough concrete on it so that after sieving, the thickness of the layer of aggregate left on top is no more than 1 piece thick.

2. Shake or vibrate the sieve until no undersize material remains on the sieve. The material that falls through should fall into a container of suitable size that has been dampened before use. The surface must be clean, moist, and nonabsorbent.

3. Remove and throw out the aggregate that stays on top of the sieve. You don't have to wipe off the smaller material sticking to the oversize aggregate.

4. Remix the batch of concrete with the shovel as little as possible to where it is uniform, and proceed to testing. For the unit weight procedure, see ASTM C138.

A Video of the ASTM C172 Procedure

ASTM C172 Quiz

view quiz statistics

© 2019 Melissa Clason


    0 of 8192 characters used
    Post Comment

    No comments yet.


    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at:

    Show Details
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the or domains, for performance and efficiency reasons. (Privacy Policy)
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)
    ClickscoThis is a data management platform studying reader behavior (Privacy Policy)