Device and method for testing inside relative humidity of cement base material

Abstract

The invention relates to a device and a method for testing inside relative humidity of a cement base material (such as cement mortar, concrete and the like) during hydration. The inside relative humidity testing device consists of a temperature humidity sensor, a sleeve, a filter membrane, sealant and a conducting wire, wherein the temperature humidity sensor is connected with the conducting wireand then sleeved into the sleeve, the temperature humidity sensor is flushed with the top end of the sleeve, the sealant is poured into the bottom of a sensing chip of the temperature humidity sensorfrom the bottom end of the sleeve, and the waterproof ventilated hydrophobic filter membrane is covered at the top end of the sleeve and adhered to the side of the sleeve by the sealant. The testing method comprises the following steps: embedding the device in the middle part of the cement base material, introducing the conducting wire to the outside of a tested object, then pouring the concrete,connecting the conducting wire and a test module, and then directly reading the test module or connecting the test module to a computer for automatic monitoring. The device has small volume and high precision; the testing method is simple; and the device and the method are not only suitable for measuring the inside relative humidity of the cement base material (such as cement mortar, concrete andthe like) at each age, but also suitable for measuring the relative humidity under various different spaces and environments.

Description

technical field [0001] The invention relates to a relative humidity test device and a test method thereof, in particular to an internal relative humidity test device and a test method thereof during the hydration process of cement-based materials (such as cement mortar, concrete, etc.). It belongs to the field of engineering material testing. Background technique [0002] The mechanical properties of cement-based materials (such as cement mortar, concrete, etc.) are inseparable from their internal relative humidity conditions. Accurately testing the relative humidity inside concrete is of great value to the research on the internal moisture migration, shrinkage, creep, stress change and crack formation mechanism of cement-based materials (such as cement mortar, concrete, etc.), especially for the internal humidity during the hydration process. The relative humidity test is more scientifically meaningful. [0003] At present, the common test method is to pre-bury the pipe w...

AI Technical Summary

Problems solved by technology

This approach has the following disadvantages: (1) It is impossible to test the relative humidity inside the early hydration process of cement-based materials (such as cement mortar, concrete, etc.); (2) The gap between the digital temperature and humidity sensor of the embedded pipeline method and the internal concrete If it is too large, it will be difficult to synchronize the relative humidity inside the concrete and the test space, and the difference is large; (3) The end of the pre-embedded pipeline is usually blocked with fabric or kraft paper to prevent leakage of cement-based materials (such as cement mortar, concrete, etc.). Materials often accumulate bleeding during the hydration process, so the relative humidity tested is by no means the real relative humidity inside cement-based materials (such as cement mortar, concrete, etc.); (4) It is difficult to seal, because the digital temperature and humidity sensor enters the cement-based material. The material (such as cement mortar, concrete, etc.) has a deep interior, and the commonly used rubber sealing ring can neither ensure that the internal air pressure is consistent with that of cement-based materials (such as cement mortar, concrete, etc.), nor can it ensure that the test space is completely isolated from the outside

[0004] The development of internal relative humidity testing technology in the hydration process of cement-based materials (such as cement mortar, concrete, etc.) lags behind, which makes such related research lack of experimental data support, which restricts the in-depth research

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