An Algorithm To Minimize Unused Lengths Of Steel Bars And Sections

Abstract

The reinforcement steel bars and other metal or wooden sections used in the construction industry are usually available in standard lengths and are cut in large numbers of specified lengths (pieces) according to the needs of the structures. The choice of how to cut these lengths is important to minimize the unused part of the standard length. If the size of the project is big, the losses may be large causing an increase in the total cost of the project. The engineers responsible for cutting the sections may use trial and error procedure to minimize the losses. The present paper demonstrates a simple algorithm for selecting the optimal cutting method to minimize the unused lengths. The solution of the problem is obtained through a two step procedure, where the first step generates possible feasible combinations made of several pieces, while the second uses a linear programming model to minimize the unused lengths, while satisfying the amounts requested from each piece. The paper demonstrates the developed algorithm through a series of examples ranging from simple to real life examples showing its ability to find an optimal solution to the problem. The concept has many applications and can produce significant savings in construction material.