What are the common problems and solutions during the construction of castables?

There are many common problems and solutions in the construction process of castables. The following castables manufacturers take you to understand some common problems and their solutions:

First, the castables appear segregation

The segregation refers to the phenomenon of precipitation or floating of solid particles in the cement paste in the castables, which leads to the uneven distribution of solid particles in the castables. The segregation will lead to uneven strength of the castables and even trigger cracks.

Solution:

1. Select proper castables, control the size and shape of solid particles, reduce the obstacles between solid particles, and reduce the viscosity of castables.

2. In the casting process, add appropriate amount of stirring agent to increase the viscosity of the slurry and prevent the solid particles from being deposited or floated.

3. Strengthen the mixing and vibration of the casting material, so that the solid particles can be evenly distributed in the slurry.

4. control the casting speed and casting height, avoid too fast or too high to cause solid particles in the slurry sinking or floating.

Second, the solidification time of the castables is too long.

The solidification time of the castables is too long, which will prolong the working period, increase the construction difficulty, and may lead to the strength of the castables not up to standard.

Solution:

1. control the water-cement ratio in the castables, reduce the amount of water appropriately, reduce the water content in the castables, and speed up the solidification time.

2. add appropriate amount of hardener in the castables to promote the early hardening of cement paste.

3. Increase the construction temperature and accelerate the solidification process by heating the castables.

4. cover the surface of the castables with heat-insulating materials to reduce heat dissipation and increase the temperature of the castables.

Third, the strength of the castables does not meet the standard

The strength of the castables is not up to standard will affect the bearing capacity and service life of the project.

Solution:

1. choose suitable cement variety and proportion to ensure that the strength of castables meets the design requirements.

2. strengthen the vibration of the castables, make the solid particles in the slurry combine closely, and improve the compactness of the castables.

3. take maintenance measures to keep the castables moist and promote the full hydration and hardening of the cement paste.

4. carry out quality testing, find out the problem of substandard strength in time, and take remedial measures to solve it.

IV. Shrinkage cracks of castables

Shrinkage cracks of castables are caused by shrinkage of castables during hardening, characterized by regular line cracks.

Solution:

1. control the water-cement ratio in the castables, reduce the amount of water appropriately, and reduce the shrinkage of the castables.

2. add appropriate amount of water-repellent agent in the castables to reduce the shrinkage properties of the castables.

3. strengthen the maintenance of the castables, slow down the water evaporation rate of the castables, slow down the shrinkage process.

4. Coat anti-cracking layer on the surface of the castables to reduce the shrinkage cracking of the castables.

V. Poor bonding of castables

Poor bonding of castables will lead to insufficient bonding strength between castables and components, affecting the overall stability of the project.

Solution:

1. improve the densification of the castables, ensure the close connection between the castables and the components, and improve the bonding strength.

2. strengthen the mixing and vibration of the castables, so that the solid particles in the slurry can be fully dispersed and evenly distributed.

3. use reinforcing agent to improve the strength and bonding performance of the castables.

4. make waterproof treatment on the surface of components to improve the adhesion between castables and components.

The above are some examples of common problems and their solutions during the construction of castables. In the actual construction, it is necessary to analyze and deal with according to the specific situation to ensure the quality of the castables and the safety of the project.