Applies to QEST Web App

Contents

Overview

Many aggregate/soil standard test methods require material to be dried to constant mass. This is most often done as part of the process of determining the moisture (water) content of construction materials. It is also frequently required when drying a material in preparation for a subsequent test, such as a sieve analysis.

There are many regional differences in standards and this is addressed in the QEST Platform by providing an option in the QEST Administrator Console, Enter Constant Dry Mass Readings, that can be set to be: “Always”, “Optional”, or “Never”. Each of these options impacts the data entry fields that are available within a worksheet and any messages/warnings that may appear. This option is available to those that have permissions to the QEST Administrator Console and can be found under Regions & Laboratories → Options as shown here:

Open

This article will discuss each of these options as they relate to completing data entry for constant dry mass.

Data Entry Fields

Constant Dry Mass may include several readings to achieve the desired results per the applicable standard. On individual test worksheets capturing a moisture content, the following fields may become available:

Field	Description	Options settings

Field	Description	Options settings
Date/Time in Oven	Date/Time wet material was placed in the oven. Entered at the time of wet mass determination. Open	Always and Optional: Field is visible and required for Constant Dry Mass determination. Never: Field is not visible.
Date and Time Out of Oven	Date/Time material was removed from the oven. Used to calculate the total drying time.	Always: Two dry mass determinations are present by default. Additional determinations may be added. Optional: One dry mass determination is present. Additional determinations may be added. Never: Date/Time out of oven and Drying Time are not visible and one field for Tare & Dry Mass is present. There is no option for adding additional determinations.
Tare & Dry Mass	Mass of material and dish when removed from the oven.
Drying Time (h)	Calculated field based on the Date/Time in and out of the oven.
Material Dry Mass	Calculated constant dry mass

Example constant dry mass determination with Always option:

Open

Additional dry mass measurements may be added as needed by clicking the '+' at the bottom of the grid.

Constant Dry Mass Messages/Warnings

There are two categories of messages/warnings for constant dry mass entry:

• Messages that are used to flag incorrect data entry for an individual dry mass reading. These are independent of any specific standard.

• Messages that are used to flag when the constant dry mass condition has not been met. These are determined by the criteria expressed in a specific standard. These messages only apply when the Enter Constant Dry Mass Readings option is set to Optional or Always.

Incorrect Data Entry Messages

The following messages/warnings will be displayed when there is an error in data entry:

Constant Dry Mass Messages

Rules associated with the constant mass determination will be enforced per the test method. These include criteria (as applicable) for minimum drying times (initial and subsequent) and tolerances for difference in mass. These messages only apply when the Enter Constant Dry Mass Readings option is set to Optional or Always and two readings have been taken. The effect for each is that Constant Dry Mass is not determined:

• Drying time cannot be determined: Date/Time out of oven is blank, but the Tare and Dry Mass value has been entered.

• Insufficient drying time: Calculated Drying Time (h) does not meet the requirement defined by the standard.

• Not dry: Constant mass, as defined by the applicable standard, has not been achieved.