Structural Investigation

Often overlooked by developers and property owners alike, the friction of your floor (or how slippery it is) is absolutely critical, especially when it comes to public or commercial buildings.

In the words of the Health and Safety Executive, “there is a level of friction below which people tend to slip over”. Fall below this level and you could be inadvertently encouraging people to fall, potentially leading to injuries, financial/insurance claims and even investigation by the relevant authorities.

The Pendulum Slip Resistance Test is the HSE’s preferred method of assessing the slip resistance of flooring. This is thanks to its portability and thus its ability to be used in the exact conditions that could result in slip accidents.

It measures the dynamic coefficient of friction (CoF) and, in simple terms, simulates the effect of a member of the public placing their heel on the ground whilst walking.

First developed by the British Research Establishment – or BRE – in the 1970s, the BRE Screed Test is now widely accepted as being the default, ‘go to’ test for measuring the soundness of a sand and cement floor screed. To put things simply, however, it’s designed to calculate whether a screed is capable of taking the loads and level of traffic for which it was intended.

Able to be used just 14 days after the screed has been laid, this test can help advise as to whether any remedial measures may be required due to issues with the mix or compaction etc.

The BRE screed testing offered by Perry Testing is carried out in accordance with British Standard BS8204 with the BRE screed test itself now forming part of the BS Code of Practices for the measurement of screed soundness.

In terms of methodology, either a 2Kg or 4Kg weight (attached to a 1m long guide) is dropped four times onto the screed with the indentation made in the concrete then being measured. We can interpret the results, considering the class of screed, whilst highlighting any suspect areas. Any problematic areas found following the BRE screed test may either be remediated or prompt further testing to be carried out.

Whilst your concrete slab may appear completely dry, that may not always be the case with significant amounts of water potentially still being present within the concrete (relative humidity). There are a variety of factors the can affect the level of relative humidity within concrete with RH sometimes remaining an issue for many months after pouring.

What’s more, recently laid concrete slabs typically contain higher levels of relative humidity the further down you go. It’s essential, therefore, that testing is carried out throughout the slab, not merely towards the surface.

Lay flooring on top of the slab before it’s had chance to properly dry out, however, and that water will try to escape, having potentially disastrous effects upon your chosen flooring.

Our team of concrete specialists will assess your slab, measuring the level of relative humidity within and determining whether it has reached a safe and acceptable level. In doing so, we can save you significant amounts of both time and money that may otherwise have been spent on the installation of a damp proof membrane.

With over 20 years’ experience, our team of structural investigation engineers are ideally placed to carry out in-depth load testing on a variety of structural elements.

Structural load testing could be required for a number of reasons. A change of use could be proposed for the building, requiring the addition of supplementary floor or perhaps heavy plant. Alternatively, there could be a need to prove performance for verification reasons or even strength following a fire.

Such testing is a widely accepted method of proving a building’s (or an individual component’s) ability to take a specific load. Such components could include…

• Slabs
• Balconies
• Balustrades
• Lifts
• Lifting beams and more.

Perry Testing will apply the test load your projects demand using hydraulic rams or test weights, continuously monitoring deflection over a specified time period before issuing a report containing our findings.

With over 20 years’ experience, our expert team specialise in carrying out tensile and shear tests on a variety of structural fixings attached to/inserted into walls, beams and more. We can tensile test rebar, threaded bar and the majority of structural fixings including…

• Eye bolts
• Stud anchors
• Anchor bolts
• Resin bolts and more.

Carried out to British Standard BS 8539, our pull out testing services can help identify damage to concrete structures or fixings, helping you to avoid potentially dangerous and concrete failures. They can also be used to test the ability of a fixing to take a specific load and are often referred to as a shear test or a tensile load test of structural fixings.

When it comes to pull off tests, however, these are used to assess the tensile bond between two surfaces or materials, examples being two layers of sprayed concrete or render coatings.

Pull off testing involves a stud being affixed to the material that requires testing. The stud is attached using an adhesive that must be stronger than the bond strength to be tested. In most cases, mechanical equipment will be used but, where greater levels of accuracy are required, more advanced, automated tools may be more appropriate.

The Schmidt hammer – or rebound hammer – is a mechanical, spring-loaded tool that, when used on concrete, provides a value that can be compared against a table, this value corresponding to a known compressive strength figure.

Widely believed to be one of the best methods of accurately assessing the compressive strength of concrete, a Schmidt hammer survey helps us identify known areas of high quality concrete. Comparing other areas against these, we can then pinpoint potentially problematic areas of concrete.

By using a Schmidt hammer, our expert team can quickly and accurately identify areas of poor quality concrete, giving you the information you need to make a properly informed decision.

Diamond drilling or coring is ideal for creating super clean, precision holes in concrete in order to extract cores for testing at one of our UKAS accredited laboratories.

Not only is the structural integrity of the material preserved throughout due to its non-percussive nature, thanks to the water used during coring, the entire process is dust-free.

Being quiet, light and easily transportable, the diamond drilling of concrete and other materials can take place almost anywhere, even in particularly tight spaces or those still occupied by the public.