Final answer:
Tremies sections are secured using strong and reliable materials like steel wire, nylon rope, and plastic straps, but not rubber bands due to their inadequacy in strength for such applications.
Step-by-step explanation:
The question pertains to the materials used to secure sections of tremies and similar concrete conveyances. Tremies are used for pouring concrete underwater or for other difficult concrete placements, and sections of tremies need to be securely fastened to prevent separation during use. The suitable materials for securing these sections include steel wire, nylon rope, and plastic straps. These materials are strong and durable enough to withstand the stresses involved in concrete pouring operations. However, rubber bands are not suitable for this purpose due to their lack of strength and reliability under the heavy load and conditions present during the conveyance of concrete.