Challenge

While Vietnam has made tremendous gains in its agricultural sector (currently the 4th largest exporter of rice in the world, 2016), investments in water management systems are critical to sustain growth, productivity and diversification.

Much of Vietnam’s irrigation and drainage systems need modernization to increase capacity and operational efficiency, and to stop deterioration, which leads to damage to lower end distribution systems, especially earth-lined channels.

One critical factor is the time it takes for the construction of the channels. This is critical as this must be undertaken during the short dry winter to prevent flooding and to minimize downtime for the irrigation system.

The Ministry of Agriculture and Rural Development (MARD) is making huge investments in improving the country’s water management infrastructure, including the adoption of innovative new technologies – and they investigated the Neoloy Tough-Cell solution.

PRS Neoloy Tough-Cell irrigation channels are 50% faster to construct and 25% lower cost than other systems

Conventional Solution

Conventional irrigation channels are made of earth lined walls. These suffer from continuous erosive forces, as well as a lack of maintenance, resulting in inefficient flows for both irrigation drainage and supply. Concrete channels are the preferred solution but typical form construction for the concrete are labor and resource-intensive, time-consuming, and more expensive.

Neoloy Tough-Cell Solution

Neoloy was selected by MARD as the fastest, most reliable and cost-effective for channel protection. The trapezoidal channel dimensions were: 3m high walls at > 41° angles; the channel bed was 3.5m bed wide; the slope of the channel bed was s=0.03%; while the water flow velocity was designed for v=3m/s.

356-50 high Neoloy Tough-Cells were used as they not only provide best quality control results for poured concrete. This size also provides a maximum reinforcement factor, such that the quantity of concrete can be reduced for even more cost savings. Fast construction was a key to this project. The channels were built during the dry winter months when farmers do not cultivate water intensive crops such as rice.

After clearing and compacting the slopes at the design dimensions and angles, fastened Neoloy sections were anchored to a 20 cm crest, and then spread out and over the channel, anchored at an average density of 4 x 4 cells.

Installation was fast about 100 m2 per day, undertaken by locally trained work crews. The 7 cm thick M200 concrete was poured into the Neoloy Tough-Cells and levelled and smoothed. Hardening time was usually 28 days.

Client Benefits

• Easy logistics of folded sections
• 50% faster installation than any other method
• Locally trained work crews
• High reinforcement factor reduced concrete by 50%
• 35% cost savings