ANS:B - collar

Large diameter reinforced cement concrete (RCC) pipes are generally joined by collar joints. Collar joints involve using collars made of the same material as the RCC pipes to connect two pipes together. These collars are usually cast as part of the pipe during the manufacturing process or are separately cast and then attached to the ends of the pipes using mortar or concrete. Collar joints provide a strong and durable connection between RCC pipes, ensuring leak-proof and structurally sound pipelines.