Concrete structures offer advantages such as strength, durability, good fire resistance, and low cost, but they also have the drawback of being prone to cracking. Next, we have a special article for you on the treatment of cracks in concrete structures:
We rigorously control the selection of materials.
Choose cement with lower hydration heat and strictly prohibit the use of cement with不合格 stability. Coarse aggregates should be selected with rough surfaces and hard textures. The gradation should be good, with a low porosity, no alkaline reaction, and harmful substances and clay content not exceeding the specifications. Fine aggregates should be medium sand with coarser particles, smaller voids, and lower silt content. External admixtures such as water-reducing agents should be used to improve the workability of concrete, reduce water consumption, and minimize shrinkage.
Secondly, scientific control of cement blending.
The design of mix proportions should utilize a low water-cement ratio and low water usage to minimize concrete shrinkage. It is strictly prohibited to arbitrarily increase the amount of cement.
Thirdly, strict control over steel bar allocation.
Rebar must be installed strictly according to the drawings. Any changes in the type, size, or quantity of rebar, or substitutions, must consider the impact on the cracking resistance of the components and require approval as per the specified process. An excessively large or small protective layer can lead to concrete cracking or cracks; a wide spacing between rebars can easily cause concrete cracking between them.
The fourth is to strictly adhere to the template engineering procedures.
Templates must be constructed reasonably to prevent deformation discrepancies among their components, which could lead to concrete cracks. The templates and supports must have adequate rigidity to prevent excessive deformation under construction loads, causing improper opening and closing. Proper timing for template removal is crucial; it should not be too early to ensure that early-age concrete is not damaged or cracked, yet also not too late to miss the peak hydration heat of concrete. Do not miss the opportunity for excellent maintenance intervention either.

Fifthly, stringent control over the casting process.

Strictly control the water-cement ratio; as the water-cement ratio increases, the tensile limit of concrete decreases, and the strength reduces, while shrinkage increases. Enhance vibration to improve the compactness of concrete. Prevent segregation during concrete pouring, ensuring even and moderate vibration. Strengthen the early curing of concrete and extend the curing period appropriately. Under conditions of high temperatures, low humidity, or strong wind speeds, early watering curing is even more crucial. If watering curing is difficult or cannot ensure adequate moisture, promptly use methods such as covering with insulating materials.
Sixthly, design the structure reasonably.
By controlling the proportion of length to height in buildings, a smaller ratio results in greater overall stiffness and enhanced ability to adjust uneven settlement. Rationally adjusting the load-bearing conditions of individual structural parts ensures even load distribution. It prevents excessive concentration of forces and reduces uneven settlement of the foundation. Appropriately strengthening the rigidity and strength of the foundation is also essential. Properly setting settlement joints and constraining the spacing of expansion joints is crucial.
Seven is to enhance the inspection and acceptance of foundations.
After excavation of the foundation pit, it is essential to promptly notify the surveying and design units for on-site acceptance. For more complex foundations, the design party should require additional drilling after the pit excavation. If unfavorable geological conditions are discovered, the foundation should be strengthened first, and only after passing the acceptance can the next phase of construction proceed. During the excavation of the foundation trench, care must be taken not to disturb the original structure. The construction sequence should be合理安排; when the distance between adjacent buildings is close, the deeper foundations should be constructed first to prevent damage to the foundations of the existing buildings. Generally, when the loads of different parts of the building vary significantly, the heavier and higher sections should be constructed first, followed by the lighter and lower sections.