Optimization of ready mixed concrete delivery for commercial batching plants of Ahmedabad, India

This paper is an attempt to develop a delivery schedule model with real time data for a commercial ready mixed concrete (RMC) plant in Ahmedabad city of Gujarat, India. Without a proper delivery schedule, either a truck-mixer would need to wait for the concrete to be placed at site or the construction site would need to wait for the truck-mixer to arrive on time. Developing an optimized dispatching and delivery sequence scheduling would improve the dispatching order of delivery of the RMC through truck-mixers from commercial batching plants to the respective construction sites. In the present research, this problem has been addressed through optimization techniques developed through mixed integer programming. Mixed integer programming considers both discrete and continuous variables which affect the delivery of RMC to the respective construction sites. The delivery scheduling problem was defined by identifying the objective function and the associated constraints. The mixed integer programming code was written with the help of MATLAB software. It has been observed after 101 iterations in MATLAB software that the dispatching sequence 1,2,2,1,1,3,2,3,2,3,3,3 has the least total waiting time of 155.4 min. After validating the same model with real time data, it has been observed that for the above dispatching sequence, the total waiting time is 153 min with one obstruction resulting in a delay of 48 min for the casting of concrete at site. Furthermore, based on the computations, it is recommended that the plant authorities need to increase the number of RMC truck-mixers from five to seven.