A method for detecting gas content in concrete

Abstract

This invention discloses a method for detecting the gas content in concrete, relating to the field of concrete gas content detection technology. The key technical points are: S1: Measure the total mass of the measuring cup lid in a dry state and in a state where the air chamber is filled with water, and obtain the mass m1 of the air chamber filled with water by the difference in mass before and after; S2: Measure the total mass of the measuring cup body in a dry state and in a state filled with water, and obtain the mass m3 of the measuring cup body filled with water by the difference in mass before and after; S3: Seal the measuring cup lid and body, and add water to the measuring cup body until water emerges from the vent valve; S4: Inflate the air chamber until the indicator shows the initial pressure P1, press the valve stem to balance the pressure between the air chamber and the measuring cup, and read the pressure value on the indicator, recording it as the zero-point gauge pressure P of the gas content. 零位 S5: The m1, m3, P1, and P obtained from S1-S4 零位 Substituting into the formula yields the mathematical model function. This method can simply, quickly, and accurately detect the gas content in concrete.

Description

Technical Field

[0001] This invention relates to the field of concrete gas content detection technology, and more specifically, to a method for detecting concrete gas content. Background Technology

[0002] During concrete construction and inspection, an increasing number of fresh concrete mixes require testing for their gas content, which is crucial for ensuring concrete durability. Existing methods for testing concrete gas content typically employ the volumetric method, which has the following technical drawbacks:

[0003] 1. The volumetric method requires purified water, which is inconvenient to carry. After the test is completed, the purified water is contaminated and cannot be used again, resulting in water waste.

[0004] 2. Due to the surface tension of water and the process of water being drawn from the vessel, water will adhere to the calibration tube, water drawing tube, and measuring cylinder wall, causing losses. At the same time, if the test time is too long, water evaporation will also cause losses. Using the measuring cylinder to read the value will cause large systematic and human errors, resulting in inaccurate measurements.

[0005] 3. Since the volumetric method does not take into account the space between the bowl and the lid, the total volume is greater than the calculated volume. Therefore, the volumetric method is not rigorous (leading to large uncertainty in the measurement results) and adds detection steps (leading to increased detection time) and a standard (leading to increased complexity). Summary of the Invention

[0006] The purpose of this invention is to provide a method for detecting the gas content in concrete, which can be simple, fast and accurate.

[0007] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a method for detecting the gas content in concrete, specifically comprising the following steps:

[0008] S1: Measure the total mass of the lid in the dry state and the state where the air chamber is filled with water, and obtain the mass m1 of the air chamber filled with water by the mass difference before and after.

[0009] S2: Measure the total mass of the bowl in a dry state and in a state full of water, and obtain the mass m3 of the bowl filled with water by the difference between the two states.

[0010] S3: Seal the lid and body of the bowl, add water to the bowl until water comes out of the vent valve, then stop adding water;

[0011] S4: Inflate the air chamber until the indicator reaches the initial pressure P1. Press the valve stem to balance the pressure in the air chamber and the measuring vessel. At this point, read the pressure value on the indicator and record it as the zero-point gauge pressure P of the gas content. 零位 ;

[0012] S5: Calculate m1, m3, P1, and P obtained from S1-S4. 零位 Substitute into the formula:

[0013]

[0014] That is, the gas content a and the equilibrium gas pressure P are obtained. x The mathematical model function between them.

[0015] By adopting the above technical solution,

[0016] Furthermore, the instrument used to measure mass in S1-S4 is an electronic balance.

[0017] Furthermore, in S4, the air chamber is filled with air using a hand pump.

[0018] In summary, the present invention has the following beneficial effects: the method only requires adjusting the initial constants (initial gauge pressure P1 of the gas chamber, zero gauge pressure P of the gas content) to... 零位 Once the mass ratio (m1 / m3) is determined, the gas content (a) and equilibrium pressure (P) can be obtained. x The functional relationship between them is used to achieve the effect of quickly and accurately detecting the gas content in concrete. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the initial state in an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the zeroing state in an embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of the test state in an embodiment of the present invention. Detailed Implementation

[0022] The following is in conjunction with the appendix Figure 1-3 The present invention will be described in further detail below.

[0023] Example: A method for detecting gas content in concrete, such as... Figures 1 to 3 As shown, the specific steps include:

[0024] S1: The mass of the gas chamber filled with water. m1: The mass of the gas content measuring instrument lid in a dry state is M1, and the total mass of the lid after the gas chamber is filled with water is M2. Then m1 = M2 - M1.

[0025] S2: The mass of the bowl filled with water. m3: The mass of the bowl in the dry state is M3, and the total mass of the bowl after it is filled with water is M4. Then m3 = M4 - M3.

[0026] S3: Fill the pot with water, ensure the lid is sealed to the pot, add water through the water inlet valve using a water injector until water comes out of the vent valve, then close the water inlet valve and the vent valve.

[0027] S4: Use a hand pump to inflate the gas chamber until the indicator reads half or one division above 0.1 MPa (taking an initial pressure of 0.1 MPa as an example). Wipe the outer surface of the measuring vessel clean and place it on an electronic balance. Adjust the gas chamber pressure to 0.1 MPa using the fine-tuning valve (this is the initial gauge pressure P1 of the gas chamber). Press the valve stem to balance the pressure between the gas chamber and the measuring vessel. The pressure indicated by the indicator at this point is the zero-point gauge pressure P of the gas content. 零位 ;

[0028] S5: Calculate m1, m3, P1, and P obtained from S1-S4. 零位 Substitute into the formula:

[0029]

[0030] This yields the mathematical model function of the gas content measuring instrument.

[0031] In this embodiment, the mathematical model function is derived in the following way:

[0032] Zeroing: Initial gauge pressure of the air chamber (P1), volume V1, corresponding water mass m1, gap volume between the air chamber and the bowl body V2, zero gauge pressure of air content P. 零位 The volume of the bowl is V3, and the corresponding mass of water is m3. According to Boyle's law, we get:

[0033] (P1+P0)V1+P0V2=(P 零位 +P0)(V1+V2)

[0034] Simplifying, we get:

[0035]

[0036] Similarly, according to Boyle's law, the equation for the gas content test process (where a is the gas content, P...) is... x (The gauge pressure value at equilibrium):

[0037] (P1+P0)V1+P0(V2+aV3)=(P x +P0)(V1+V2+aV3)

[0038] Simplifying, we get:

[0039]

[0040] Substituting the relationship between V1 and V2, and considering that the volume and mass of the same batch of water at the same temperature are directly proportional, we obtain the formula for the measurement mathematical model:

[0041]

[0042] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A method for detecting the gas content in concrete, characterized in that: Specifically, the following steps are included: S1: Measure the total mass of the lid in the dry state and the state where the air chamber is filled with water, and obtain the mass m1 of the air chamber filled with water by the mass difference before and after. S2: Measure the total mass of the bowl in a dry state and in a state full of water, and obtain the mass m3 of the bowl filled with water by the difference between the two states. S3: Seal the lid and body of the bowl, add water to the bowl until water comes out of the vent valve, then stop adding water; S4: Inflate the air chamber until the indicator reaches the initial pressure P1. Press the valve stem to balance the pressure in the air chamber and the measuring vessel. At this point, read the pressure value on the indicator and record it as the zero-point gauge pressure P of the gas content. 零位 ; S5: Calculate m1, m3, P1, and P obtained from S1-S4. 零位 Substitute into the formula: That is, the gas content a and the equilibrium gas pressure P are obtained. x The mathematical model function between them.

2. The method for detecting gas content in concrete according to claim 1, characterized in that: The instruments used to measure mass in S1-S4 are electronic balances.

3. The method for detecting gas content in concrete according to claim 1, characterized in that: In S4, the air chamber is filled with air using a hand pump.

Images