The solution to the substandard strength of concrete
The Langry Schmidt Rebound Hammer is a practical tool for professional concrete strength measurement, and the integrated digital swiss hammer directly records and automatically displays the measurement data. However, if the measured concrete strength does not meet the design requirements, the following are the experiences and solutions I have summarized for you.
First when the construction site structure rebounds, what should I do if the concrete strength fails to meet the design requirements?
There are many reasons why the strength of structural concrete fails to meet the design requirements, the main ones are as follows:
The early curing of concrete is too poor or the vibration is not compact;
The strength of standard maintenance for 28 days cannot reach the design strength value of the mix ratio;
The collapse of the concrete mixture is fast, and it is not easy to pour after reaching the construction site, resulting in secondary water addition and reducing the strength of the concrete;
When pouring small components (such as structural columns, etc.), too much material (5 cubic meters or more) is required at one time, resulting in the unloading of the material within five hours, and the concrete poured later will reduce the strength;
The quality of raw materials for concrete production has declined, such as excessive mud content of sand and gravel, excessive shale particles of stones, excessively coarse fly ash, reduced water reduction rate of admixtures without increasing the dosage, and low strength of cement, etc. ;
Second, the processing method
1. If the carbonation depth of concrete exceeds 2mm within half a year, and the carbonation depth of concrete exceeds 3mm within half a year, it means that the early curing of concrete is too poor or the vibration is not compact, which is the responsibility of the construction unit. Most of the concrete constructed in winter has a large carbonation value.
2. To improve the rich strength of the concrete mix ratio, the strength must reach the design strength value of the mix ratio for 28 days after standard curing (ie: design strength + 1.645 standard deviation).
3. The admixture must be tested every time it enters a car, and the collapse must be qualified over time.
4. When pouring small components such as structural columns and the pouring speed is slow, the delivery volume of each car should be kept at 3 to 5 squares, and the car should not be full.
5. Find out which raw material has the quality problem and correct it immediately.
Langry is the specialized manufacturer of rebound hammers, we provide rebound hammer OEM production for many companies, are exported all over the world, mainly for high-end products, is currently China's largest rebound hammer factory, quality is the best, we produce rebound hammer spring adopts high-quality spring, the service life of 3 to 5 times that of another ordinary rebound hammer. If you are interested in our products, you can test them and cooperate with us after you are satisfied.