Concrete Vibration and Compaction Technology

Concrete vibration and compaction is a process that uses vibrating machinery to increase the fluidity of the concrete mixture, facilitating its formation and enhancing its density. After the concrete mixture is poured, the vibrating machinery transmits vibration energy at a specific frequency, amplitude, and excitation force to the mixture. This significantly reduces the cohesive and internal frictional forces within the mixture, causing it to behave like a heavy liquid. As a result, the aggregates settle and align under their own weight, expelling air bubbles and eliminating voids. This ensures a dense arrangement of aggregates and cement paste, effectively filling the formwork.

The effectiveness and productivity of vibration compaction depend on the type of vibrating machinery, vibration parameters (amplitude, frequency, excitation force), and the properties of the concrete mixture (aggregate size, slump). The properties of the concrete mixture influence its natural frequency, causing different damping and attenuation effects when vibrations of various parameters propagate through it. Therefore, there exists an optimal frequency and amplitude suited to the specific mixture.

Types of vibrating machinery include internal vibrators, surface vibrators, external vibrators, and vibrating tables.

• Internal vibrators, also known as immersion or poker vibrators, are used for compacting beams, columns, walls, thick slabs, and mass concrete structures.
• Surface vibrators, also called plate vibrators, are used for compacting thin elements such as floor slabs and pavements.
• External vibrators, also known as form vibrators, transmit vibrations to the concrete mixture through the formwork and are used for compacting elements with small cross-sections and dense reinforcement.
• Vibrating tables are fixed production equipment in concrete product plants, used for compacting precast reinforced concrete elements.