Permeability Test Apparatus
It is important to use concrete testing equipment to check the permeability of the concrete. This test is very important when it comes to dealing with the durability of concrete. In this blog, we will discuss all the aspects of the permeability test.
What is a permeability test?
It is particularly useful in checking concrete quality when it is being used to water retaining structures or watertight sub-structures. This type of structure faces harsh environmental conditions. And that is why they require low porosity as well as permeability. In case the concrete is not tested, it can result in the degradation of reinforced concrete. You can understand it by an example. When there is a corrosion of steel it leads to a volume increase of the steel. It may also lead to cracking and eventual sapling of the concrete.
Under the permeability test you get to know the penetration capacity of liquids, ions, and gases can penetrate into the concrete. The test is highly useful in the civil construction industry. It will assess the easiness with which water, gas, and deleterious matter such as chloride ions can penetrate into the concrete.
The procedure of permeability test
The testing methods cover a whole range of topics, you can refer to Concrete Society Technical Report No. 31 for more details. In a simple way, there are two widely established methods that are: The initial surface absorption test (ISAT) and the modified Figg air permeability test.
Initial surface absorption test
In the ISAT, the machine determines the rate of water and air penetration on the concrete surface layer. In the industry, there is another new methodology that uses a modification of the laboratory test to determine chloride ion permeability.
You will get the whole details of this test on BS 1881:Part 5. The test is good to measures surface water absorption. Here You require to seal a cup of the surface area of 5000 mm2 (Minimum) to the concrete surface and water is filled.
The experts observe the water observation rate under a pressure head of 200 mm is measured by movement along a capillary tube attached to the cup. If you are looking for the equipment capable of doing this test, you can contact https://civillabequipmentmanufacturer.com/initial-surface-absorption-test-apparatus/
This way, experts do the permeability test. This is the basis of initial surface absorption, which is defined as the rate of water flow into concrete per unit area at a stated interval from the start of the test at a constant applied head at room temperature.
Modified Figg permeability Test
Under the modified Figg air permeability test, the machine measures the ease of water penetration into the surface layer of the concrete. You need to make a hole of 10 mm diameter is drilled 40 mm deep normal to the concrete surface. Then insert a plug into the hole in the airtight cavity. In the air permeability, the air pressure gets reduced to –55 kPa by using a hand-operated vacuum pump. As compared to the ISBT, this test requires more supervision.
Overall the tests are conducted to know the permeability of the outer layer of concrete. The test is done on the outer layer, as it is the most important parameter to check the durability of concrete.
Most of these methods measure the permeability or porosity of the surface layer of concrete and not the intrinsic permeability of the core of the concrete. Experts use their knowledge to understand the permeability of the concrete. While making buildings, roads, various infrastructure projects, it is important to do the test. The test gets conducted on the outer layer thus providing the first defense against any degradation. Bring the test machine from https://civillabequipmentmanufacturer.com/permeability-apparatus-tree-cell-model/ and enhances check the concrete quality before using it.
Concrete Permeability Test Apparatus (Three Cell)
(Standards:IS 3085, DIN 1048)
The concrete permeability apparatus three cell set of a three pieces mild steelconcrete permeability cell of Square cross-section fitted on a stand and a pressure chamber is connected to the cell through tube and T-connector mounted on the stand with sleeve packed valve and rubber hose pipe with end connections. The cell assembly consists of one base plate and one top plate connected to nozzles. The pressure chamber is fitted on the front of the board with a pressure regulator which helps to regulating the pressure from 0-15kg/cm sq. and set of three pressure Gauge is for indicating the current pressure in the concrete cell.
The apparatus is supplied with a measuring cylinder 500cc to measure percolated quantity to water. Permeability Cell Consists of a metal cylinder with a ledge at the bottom for retaining the specimen, a flange at the top, removable cover plate and a funnel. A rubber gasket is seated in matching grooves, between the cell and the cover plate, to render the joint water tight.
Optional AccessoriesAir Compressor
It is a wise decision to do the permeability test on concrete before using it in any way. This way, you increase the durability and long-lasting capacity of the concrete.