Frost Heave Test and Study Method Using a Customized Test Chamber

What is Frostheaval Phenomenon?

Frost heaving is a natural phenomenon whereby, in freezing conditions, the ground swells due to the ice that has penetrated it.

Ice grows upward: the growth of its crystals is held back by the ground but this is not enough to counteract the formation of lenses within it.

For this type of testing, FDM offers its customized FDM solutions, designed and manufactured in Italy since 1949.

The ice crystals then bind to the ground forming a single solid block that eventually lifts it up.

 Normally, strength increases as temperature decreases.

This dangerous process leads to damage to roads and buildings, to varying degrees depending on the type of soil and its moisture content.

Leading researchers such as Konrad, Morgenstern and Penner have studied frost heaving using various laboratory testing, to analyze the phenomenon closely.

Over time, some of the most important research centers around the world have wanted to propose standardized testing methods for laboratories.

This is to guide the latter in better analyzing the characteristics of frost heave.

The main points of reference are:

• TRRL (Transport and Road Research Laboratory) in the United Kingdom
• The British Standard Institution, also in the UK ( BS 812-124:2009 )
• The ISO (International Organization for Standardization) with the ISO 13793:2001
• JGS (Japan Geotechnical Society) in Japan (JGS 0172)

How can frost heave be simulated?

Preventing frost heave is extremely important but not at all simple.

A major client told us about the difficulty of performing this type of test and the unavailability of equipment on the market that could actually verify the phenomenon.

For this reason, at FDM, we have developed a customized machine capable of automatically performing the relevant frost heave tests, simulating real environmental conditions.

The SRU Test Chamber (FHU812) was developed according to the British Standard BS 812-214.

It is made up of two different environments: one with a controlled temperature and one containing all the power and control components for the machine's operation.

The temperature-controlled environment is divided into two containers, both independent of each other.

1. Water container: positioned at the bottom and containing water maintained at 4°C
2. Air container: positioned high and containing air refrigerated at -17°C

Between the two containers there is an intermediate cradle and a wooden support that holds the samples to be tested.

The chamber also comes with a reference frame and 9 brass rods.

The 9 bars correspond to the 9 test pieces which, freezing by capillary action, cause the brass bars to rise.

How the SRU Machine Works

It is an exact simulation of the real phenomenon, therefore it imitates the freezing of the soil.

Water from the temperature-controlled environment rises and freezes, raising the bars.

The test manager can thus measure the lift of each specimen simply by measuring the lift of the bars.

The machine is equipped with a touch screen that automates the test as much as possible.

The user must load the chamber with samples, install the reference frame, insert the brass rods, and then start the test with a button on the touch screen.

The machine will take care of the rest by alerting the user whenever it is necessary to take the lifting measurement.

At the end of the test, it is possible to remove the USB key and download to a PC all the recorded data from the eleven probes installed in the test volume.

Download the Technical Specifications for this Test Chamber

We facilitate your tests and produce customized machines

At FDM, we are constantly seeking solutions to improve environmental testing in order to assist scientific researchers with efficient, reliable, and above all, customized machinery for every type of application.

With this specific project, we were able to help a researcher who needed to streamline his testing process.

He himself revealed to us that the results were excellent.

SRU has accelerated our client's study processes by 60% compared to their previous methods and allowed them to obtain more reliable values.

At FDM, we care about the needs of each customer, listen to all requests, and strive to meet all your testing requirements, even if it's a single customized machine.

By contacting FDM, you'll receive immediate answers on the feasibility and costs of your projects, with maximum transparency and professionalism, for over 70 years.

Discover the FDM solution for frost heave testing: our frost heave test chamber simulates the frost heave phenomenon according to BS812:PT124:1989 with 9 simultaneous specimens.

Reference Standards

• ISO 17892-5 — Geotechnical investigation and testing, laboratory testing of soil, Part 5: Incremental loading oedometer test, reference for the characterization of cohesive soils.
• UNI EN 13286-51 — Bound and unbound mixtures: Test methods for determining the freeze-thaw resistance of cemented mixtures.
• ASTM D5918 — Standard Test Methods for Frost Heave and Thaw Weakening Susceptibility of Soils, American reference method for cryolifting.
• AASHTO T 103 — Standard Method for Soundness of Aggregates by Freezing and Thawing, a test of durability of aggregates for road subgrades.
• ISO 10545-12 — Ceramic tiles: Determination of frost resistance by freeze-thaw cycles.
• EN 12390-9 — Testing hardened concrete: Freeze-thaw resistance, slab and CIF methods for concrete.

Authoritative Sources

• ASTM D5918 Frost Heave. International reference method for characterizing frost susceptibility.
• ISO – International Organization for Standardization. Maintains the ISO 17892 series on geotechnical laboratory testing.
• AASHTO – American Association of State Highway and Transportation Officials. Publishes T 103 and manuals for frost-resistant pavement design.

Frequently Asked Questions about the Cryolift Test

What is the phenomenon of frost heave?

Frost heave is the volumetric uplift of saturated soil caused by the formation of ice lenses during freezing. The mechanism is well described by Taber's theory: the thermal gradient induces capillary water crystallization at the freezing front, while the residual water below migrates by matrix suction toward the cold zone, fueling lens growth. The phenomenon requires three simultaneous conditions: (1) susceptible soil (silts and silty clays with available fraction of water (water table within 1.5-2 m from the freezing plane); (3) prolonged frost with slow thermal gradient (typically 1-2 cm/day). The uplift can reach 10-20 cm in a winter season, causing damage to road pavements, shallow foundations, railway tracks. Pure clays are not susceptible (too low permeability), clean sands neither (insufficient capillarity): the critical range is silt with

How do you simulate freeze-thaw in the laboratory?

The ASTM D5918 method requires a cylindrical specimen (150 mm diam x 150 mm h) to be placed in an atmospheric pressure cell with a base at -3°C and a top at +3°C , producing a gradient of 40 K/m. Saturation is maintained by supplying water from a hydrostatically balanced tank. Test duration: 8 freeze-thaw cycles of 8 h freezing + 16 h thawing, total 8 days. The following are continuously measured: (a) head lift with an LVDT, resolution of 0.01 mm; (b) water flow absorbed by the specimen (ml/h); (c) temperature at 5-7 axial points with type T thermocouples; (d) cryosuction pressure with tensiometers. The results classify the soil as: Negligible < 1 mm/day, Low 1-2 mm/day, Medium 2-4 mm/day, High 4-8 mm/day, Very High > 8 mm/day of maximum heave. The chamber must ensure control of +/- 0.2°C on the edge temperatures and stable ambient relative humidity to avoid drying out the specimen.

When is it critical in civil engineering?

Frost heave is a key factor in the design of: (1) road pavements in areas with frost depths > 0.5 m (Alpine Northern Italy, Central-Northern Europe, Canada, Russia), where it requires frost-free granular layers 40-80 cm thick under the foundations; (2) shallow foundations of buildings, to be positioned under a maximum frost depth + 20 cm (UNI EN 1997 Eurocode 7); (3) underground tanks and drinking water pipes, with a minimum depth of 1.2 m in the Po Valley; (4) high-speed railways , where vertical tolerances < 2 mm require non-susceptible soils and drainage; (5) tunnels and pile foundations in permafrost areas. The cost of failure to design is high: pavement repairs 50-200 EUR/m2, foundation heave with cracking of buildings. Pre-project tests on undisturbed samples cost EUR 500–2000 per specimen and allow for the optimization of layer thicknesses and drainage systems.

Why a custom FDM climate chamber?

Frost heave testing requires non-standard chambers for specimen dimensions (150-300 mm diameter), requires controlled thermal gradient , constant pressure water supply, instrumentation access from head and base. Standard commercial climatic chambers do not have suitable geometry. A custom FDM chamber integrates: (1) independent upper/lower Peltier or glycol thermostatic plates with +/- 0.1 C control; (2) 80 mm polyurethane foam insulated compartment with vapor barrier; (3) water supply system with peristaltic pump and in-line scale for absorbed flow measurement; (4) mechanical crosshead with LVDT for heave measurement with thermal compensation; (5) multi-channel acquisition for 16-32 thermocouples; (6) dedicated software for automatic cycling and ASTM compliant reporting. The custom project is required for university geotechnical laboratories, ANAS/Autostrade for subgrade material testing, aggregate manufacturers for certification.