Water penetration test - Permeability test
The main objective of the water penetration test in bridges or tunnels diagnostics is the determination of resistance or durability of concrete extracted from elements of structure exposed to the water flow. The water permeability tests are the best for evaluating concrete durability under hydrostatic pressure and as a good indicator of its quality. The application in durability assessment of concrete elements of the existing structures is growing. The permeability test should be considered as an essential one to evaluate the case whereby concrete is subjected to hydrostatic pressure.
Pressurized water acts on the surface of the hardened concrete at a constant pressure of 500 (± 50) KPa, usually for a period of 72 hours. After the test, the sample should be immediately split in the plane of water penetration and the contour of the wetted area should be marked. The apparatus consists of a robust steel frame with clamping system, incorporating the hydraulic circuit, valves, gauge to check the water pressure and measuring transparent burettes mounted on top of the apparatus. The clamping system is adjusted for cube or prismatic specimens up to 200 mm side and cylinders up to 300 mm height.
After the pressure has been applied, the specimen should be split in half, perpendicularly to the face on which the water pressure was applied. When splitting the specimen, and during the examination, the face of specimen exposed to the water pressure should be placed on the bottom. As soon as the split face has dried to such an extent that the water penetration front can be clearly seen, the water front on the specimen can be marked .
Water penetration test can be distinguished into two types:
- performed on the samples in laboratory – in a test chamber with water pipe ensuring continuous flow and homogeneous water coverage and air pressure applied,
- performed on the built walls in the construction site conditions – in a test chamber with a box format and internal dimensions 160 mm x 340 m and no air pressure is used.
Process/event to be detected or monitored
Depth of the penetration of water after observation of the fracture structure after splitting the sample. The wet area is darker.
Physical quantity to be measured (e.g. actions, displacements, deformations, dynamic structural properties, material properties including mechanical, electrical and chemical properties, relative displacements of the two sides of a crack, etc.).
Measurement of the maximum range of water penetration from the surface. Maximum average depth for examined samples.
Induced damage to the structure during the measurement
For diagnostics of existing civil engineering structures it is necessary to collect samples from the structure in a borehole form, therefore the method is destructive.
Measurement type (static or dynamic, local or global, short-term or continuous, etc.)
Background (evolution through the years)
Historically tests on water penetration have been performed on windows by exposing them to rain and additional pressure.
The ASTM E1105 (Standard Test Method for Field Determination of Water Penetration of Installed Exterior Windows, Skylights, Doors, and Curtain Walls, by Uniform or Cyclic Static Air Pressure Difference) test procedure was specifically written for field testing and as a component to the quality assurance and commissioning process of a building enclosure. ASTM E1105 uses a calibrated spray rack to simulate rain from the outside and a negative pressure chamber inside to simulate wind. The procedure describes how to test with either a constant or a fluctuating interior pressure.
Another standard – ASTM E331 has been established in 1967. Further development consisted of transition from manual to automatic methods of testing. ASTM E514 M-20 Standard Test Method for Water Penetration and Leakage Through Masonry subjected to wind-driven rain. Has been introduced in 1990. US Army published in 1992 a procedure for determining the permeability of concrete subjected to water pressure (1,38 MPa) with a code - COE CRD-C 48-92 as a Handbook for Concrete and Cement Standard Test Method for water permeability of Concrete..
The ASTM C1601-10 Standard Test Method for Field Determination of Water Penetration of Masonry Wall Surfaces has been introduced in 2010 to determine criteria for water penetration resistance of masonry wall.
General points of attention and requirements
Design criteria and requirements for the design of the survey
Procedures for defining layout of the survey
Sensibility of measurements to environmental conditions.
Procedures for calibration, initialisation, and post-installation verification
Procedures for estimating the component of measurement uncertainty resulting from calibration of the data acquisition system (calibration uncertainty)
Requirements for data acquisition depending on measured physical quantity (e.g. based on the variation rate)
Requirements and recommendations for maintenance during operation (in case of continuous maintenance)
Criteria for the successive surveying campaigns for updating the sensors. The campaigns include: (i) Georeferenced frame, i.e. the global location on the bridge; (ii) Alignment of sensor data, relative alignment of the data collected in a surveying; (iii) Multi-temporal registration to previous campaigns; and (iv) Diagnostics.
An identification of sample should be included in the report, the direction of the supply of water in relation to the formation of the sample (perpendicular or in parallel), date, maximal penetration depth in mm, leak outline/cross section.
Lifespan of the technology and required maintenance (if applied for continuous monitoring)
Water penetration test is not used in continuous monitoring.
Interpretation and validation of results
Expected output (Format, e.g. numbers in a .txt file)
Cross-section of the drenched area of the split sample; the maximum depth of penetration, expressed in mm after different days period.
Interpretation (e.g. each number of the file symbolizes the acceleration of a degree of freedom in the bridge)
Cross section shows the image of dampness for different samples, which can be compared for different concrete classes. Values present the maximum depth of water penetration in concrete samples.
If the water penetration depth is below 50 mm concrete is classified as impermeable and if below 30 mm as impermeable in corrosion conditions .
Specific methods used for validation of results depending on the technique
Quantification of the error
Quantitative or qualitative evaluation
The water penetration depth should be detected with accuracy to 1 mm.
Method can be performed with use of apparatus for testing water permeability with automatic control, which allows testing several samples simultaneously. Possibility of automatic testing in different research cycles as well as pressure reading directly from the pressure gauge, automatic water supply simplifies the procedures.
Guidelines for performance of test do not specify precise age of the sample at which the test should begin, nor the cut-off age of concrete that can be tested. This fact indicates on the possibility of different result for this property.
Possibility of automatising the measurements
On the market there are available fully automatic apparatuses for cubic concrete specimens, where the water permeated through the test specimen is directly collected and measured. Each sample cell includes pressure control manometer, and the apparatuses are supplied with an automatic pump.
No specific barriers to be included.
- EN 12390-8:2019, Testing hardened concrete - Part 8: Depth of penetration of water under pressure
- PN-EN 206+A2:2021-08, Concrete – requirements, properties, production and compliance
- 1.11.3 ASTM C1601 – 11 Standard Test Method for Field Determination of Water Penetration of Masonry Wall Surfaces
- DIN 1048 - Testing concrete; testing of hardened concrete (specimens prepared in mould)
- DIN 1045-2 - Concrete, reinforced and prestressed concrete structures - Part 2: Concrete - Specification, performance, production and conformity - Application rules for DIN EN 2061.
Relevant knowledge fields
- control of blasting process,
- quality control in production of anti-corrosion coatings,
- water penetration of masonry wall surfaces.
- loss of section
- wire break
- tensioning force deficiency.
Type of structure
- curtain walls
Spatial scales addressed (whole structure vs specific asset elements)
Water penetration test can be useful when used for the samples collected from the places particularly vulnerable to corrosion and chemical attack.
- reinforced concrete
Not reference projects