Sample Reduction

UKAS Accredited

Standard(s): BS EN 932-2:1999
Lab Test
Sample reduction is the process of decreasing the size of a bulk material sample while maintaining its representativeness. In construction materials testing, large field samples of soils, aggregates, or other granular materials often need to be reduced to a manageable size for laboratory testing. Methods such as riffle box splitting or quartering ensure the reduced sample still accurately reflects the characteristics of the original material.

Enquire about this test

The Process

The sample reduction process begins with a bulk sample collected from site. The material is then mixed and reduced using recognised techniques such as a riffle box splitter, manual quartering, or by carefully separating the material to obtain a test portion of a specified mass within a small tolerance. These methods divide the sample evenly, preventing bias and ensuring consistency before laboratory testing begins.

The Reason

Bulk samples collected from construction sites are typically too large to be used directly in laboratory tests. Reducing the sample allows technicians to obtain a precise quantity required by specific testing standards while preserving the original material distribution. Proper reduction prevents segregation of particles and ensures the test results remain representative and reliable.

The Application

Sample reduction is commonly used prior to laboratory testing of soils, aggregates, and other construction materials. It ensures that the portion used for tests such as grading analysis, compaction testing, or strength assessments accurately represents the material delivered to site. This helps engineers and contractors make confident decisions about material quality and compliance with project specifications.

Frequently Asked Questions

Why should sample reduction be carried out by a laboratory like Amtest?

Correct reduction techniques are essential to maintain sample representativeness. Amtest follows recognised standards and controlled procedures to ensure the reduced sample accurately reflects the original bulk material.

What types of materials can Amtest reduce for testing?

Amtest can reduce samples of soils, aggregates, and other granular construction materials before they undergo laboratory testing such as grading, compaction, or strength tests.

View more Aggregates testing services:

View all
Aggregates
UKAS Accredited
Lab Test

Plastic Limit

Determination of the plastic limit of fine-grained soils in accordance with BS EN ISO 17892-12:2018+A2:2022.
BS EN ISO 17892-12:2018+A2:2022
View Test
Aggregates
UKAS Accredited
Lab Test

Particle Size Distribution

Determination of particle size distribution of aggregates using sieving in accordance with BS EN 933-1:2012.
BS EN 933-1:2012
View Test
Aggregates
UKAS Accredited
Lab Test

Sample Reduction

Sample reduction by riffle box, by quartering, or to a test portion of a specified mass within a small tolerance
BS EN 932-2:1999
View Test
Aggregates
UKAS Accredited
Lab Test
Site Test

Dynamic Cone Penetration (TRL-DCP)

Rapid measurement of the in-situ strength of existing flexible pavements constructed with unbound materials.
DMRB, CS 229 Data for Pavement Assessment Rev.0: 2020
View Test
Aggregates
Site Test

In-Situ California Bearing Ratio (CBR)

Penetration of soil with a plunger over a standard area. The harder the surface, the higher the CBR percentage.
View Test
Aggregates
UKAS Accredited
Site Test

Constituents of Course Recycled Aggregates

Ensure the quality and compliance of recycled aggregates with our constituents analysis, supporting sustainable and reliable construction practices.
BS EN 933-11:2009
View Test
Aggregates
UKAS Accredited
Lab Test

Plasticity Index

A higher Plasticity Index indicates a greater range of water content where soil remains plastic, signifying higher compressibility and potential for settlement.
BS EN ISO 17892-12:2018+A2:2022
View Test
Aggregates
UKAS Accredited
Lab Test

Water Content

Determination of the water content of aggregates in accordance with BS EN 1097-5:2008.
BS 1377-2:2022
View Test
Aggregates
Site Test

In-Situ Bulk Density Nuclear Method

The in-situ bulk density nuclear method ensures soil compaction meets construction standards by measuring density and moisture directly on-site.
BS 1377-9:1990
View Test
Aggregates
UKAS Accredited
Lab Test

Resistance to Fragmentation – Los Angeles Test

Subjects a coarse aggregate sample to abrasion, impact, and grinding.
BS EN 1097-2:2020
View Test
Lab Test
Sample Reduction
BS EN 932-2:1999