When it comes to construction, particularly in the pouring of concrete for columns, utilizing the right materials and techniques can make a significant difference in the project's success. One effective method is the use of flexible plywood for column formwork. This article will elaborate on the best practices for pouring concrete with flexible plywood molds, especially for structures that require height considerations in their design. 

Concrete Pouring Method for Column Construction:

For pouring concrete in columns with a height of up to 7 meters, it is advisable to perform the pour in one operation. However, when the height exceeds 7 meters, it is recommended to divide the process into two phases. After the first pour, you should wait approximately 30-60 minutes before commencing the second pour. This allows for adequate setting time and minimizes the risk of any structural issues that can arise from continuous pouring.

Key Guidelines:

1. Free Fall Height: It is crucial to ensure that the free fall height of the concrete from the pump pipe does not exceed 2 meters. If this height is unavoidable, it is recommended to extend the hose or use a series of chutes to control the flow better. This practice helps maintain the integrity of the concrete mix and reduces the potential for segregation.

2. Vibration Techniques: When using an immersion vibrator, it’s important to insert the vibrator quickly and withdraw it slowly. While vibrating the current layer of concrete, the vibrator should penetrate into the layer beneath by approximately 5-10 cm. Over-vibration must be avoided as it can lead to a separation of aggregates. Additionally, the vibrating rod should never touch the reinforcement bars or the flexible plywood to ensure that the formwork remains undamaged and the concrete is properly consolidated.

3. Layered Pouring and Vibration: For columns and wall concrete, it is crucial to pour and vibrate in layers. Each layer's thickness should be controlled to approximately 500 mm. Distributing the concrete pouring points in a scattered arrangement, while continuously pushing the material, helps to maintain consistency and prevents any cold joints. It is essential to monitor the duration of concrete pouring to ensure that it remains uninterrupted and adheres to the project's timeline.

In conclusion, the use of flexible plywood in column formwork provides a reliable method for pouring concrete effectively. By following these guidelines on free fall height, vibration techniques, and layered pouring, construction professionals can ensure a successful and efficient pouring process that results in durable and sturdy columns. Incorporating these practices will not only enhance the quality of the structure but also streamline the workflow on construction sites.

For further insights into advanced construction techniques and the use of flexible formwork, be sure to follow our blog for more expert tips and industry updates.