Concrete Cube Testing Overview
There are many instances where fresh concrete is used on construction projects. It can be batched on-site or delivered in a mixer truck from a static plant.
The control of concrete quality is imperative in order to avoid structural failure. The two primary tests are the workability using the slump test and the cube compressive strength of the delivered mix. In both cases, a strict sampling technique is used to ensure the integrity of the testing.
Projects and budgets can be at risk if the concrete is not tested to the relevant BS or BS EN Standards. Testing concrete can ensure it can withstand the level of compression forces required in the original design. Simtec can provide UKAS accredited testing in accordance with BS or BS EN standards delivering the highest standard or professional compliance.
Concrete Cube Testing In Detail
Concrete Cube Testing: The Process
In order to prove the strength of a fresh concrete mix, cube samples are manufactured in either 100mm or 150mm cube moulds. A sample of the mix is taken in accordance with BS EN 12350-1 (verification required for BS EN number) and a set of six cubes are made in accordance with BS EN 1881-108 or its replacement BS EN 12390-2. The cubes are then cured in a temperature-controlled water bath for the specified number of days and crushed in a specialised hydraulic press to determine the compressive strength. The cubes are filled in two or three layers with the wet concrete, with each layer being compacted with a standard tamping bar and a minimum specified number of strokes. The tops of the cube samples are floated off level with the top of the moulds using a polished float. Protected from the elements, the samples are allowed to cure overnight and are carefully removed from the moulds the following day. After the cubes have been allocated a unique number, which is written on the top face along with the casting date, the cubes are placed in a curing tank for a specified number of days at a temperature of 20°C.
The cubes are subsequently tested in a compression machine where they are subjected to increasing load until failure. The resultant crushing/compressive strength can then be compared to the design strength of the content. Cubes are generally crushed at seven days in order to gain an indication of the 28-day strength, as 7-day cubes generally achieve two-thirds of the ultimate strength.
In some extreme cases, many cubes are taken, and the tests carried out every few days, but as a general rule, the 28-day strength is taken as the target. For some concrete not reaching the desired 28-day strength, the crushed cube remains are submitted for chemical testing to confirm the cement content and water/cement ratio.
Test cores can be drilled from hardened concrete, enabling strength tests to be carried out on older or suspect material. These can be drilled vertically or horizontally and tested in a similar manner to cubes. Visual examination of concrete cores can be used to confirm the aggregate type and estimate the void content.
Our UKAS accreditation is limited to those activities described on our UKAS schedule of accreditation found here.
Why we carry out Concrete Cube Testing ?
Simtec is your partner in keeping your project moving forward with ease. Our extensive testing capacity allows peace of mind and assurance when you need to move to the next stage of your project and compliance with British Standards.
Concrete Cube Testing allows you to understand the reliability and strength of hardened concrete under the designed level of compression to ensure its fit for purpose and indicate where it will fail.
Test cores can be drilled from already hardened concrete to investigate suspected material. The preference is always to test freshly mixed concrete, allowing results to be feedback to suppliers allowing for changes in the mix, reducing the risk to the overall project in time and cost.
Simtec has successfully delivered services to the construction and civil engineering industry since 2007. We are proud of our high level of customer service and integrity and have a proven track record which has attributed to our growth within the sector. Contact us today, using the form, to find out more about our field-testing services and how we can help you keep your project on track and within budget.
Simtec Concrete Cube Testing In Our Laboratories
Simtec Material Testing has the capacity to carry out Concrete Cube Testing at our Leicestershire Laboratories.
Our laboratory testing is constantly monitored internally and annually audited to provide the level of service expected by our clients. Our comprehensive range of tests is UKAS accredited to guarantee the quality and validity of results and reporting.
Frequently Asked Questions
The Simtec approach
Fast, accurate assurance when you need it.
We act as the grease-in-the-wheels of the construction industry, ensuring work progresses at pace with unnecessary costs avoided. Since 2007 we have established ourselves as the trusted name in construction materials testing, building a professional, practical and methodical business culture from the top down.
Our approach is simple – we believe shared knowledge is the foundation on which we all progress. That’s why we have documented and routinely share best practices with our partners and clients to minimise everyone’s exposure to risk.
Every contract we undertake is measured against the Simtec Optimum Compliance Benchmark –data consisting of best practice criteria, designed to help you achieve consistently high compliance approval and avoid cost of delay or remedial work. We’re proud that the integrity, rigour and safeguarding we provide has established Simtec as a trusted testing partner to firms across the UK’s construction sector.