Applied Soft Computing Journal 98 (2021) 106915 Contents lists available at ScienceDirect Applied Soft Computing Journal journal homepage: www.elsevier.com/locate/asoc A soft computing approach based on critical chain for project planning and control in real-world applications with interval data S. Aramesh a , S.M. Mousavi a,∗ , V. Mohagheghi a , E.K. Zavadskas b,∗ , J. Antucheviciene c a Department of Industrial Engineering, Faculty of Engineering, Shahed University, Tehran, Iran b Institute of Sustainable Construction, Vilnius Gediminas Technical University, Vilnius, Lithuania c Department of Construction Management and Real Estate, Faculty of Civil Engineering, Vilnius Gediminas Technical University, Vilnius, Lithuania article info Article history: Received 29 April 2020 Received in revised form 12 October 2020 Accepted 16 November 2020 Available online 24 November 2020 Keywords: RCPSP Expert weighting Buffer monitoring Hybrid decision making Bi-directional projection measurement Interval information abstract Resource-constrained project scheduling problem (RCPSP) has been one of the most important topics in project scheduling in recent decades. RCPSP, due to the strategic importance of the projects and internal and external pressures for timely completion, is a very challenging task. When executing a project, controlling and monitoring it also becomes vital. This paper aims to present a new soft computing framework that incorporates decision making about RCPSP parameters, RCPSP modeling, adding project and activities buffer, and monitoring the project. In the decision-making procedure, the activities durations are interval, but resource requirements are real numbers. So, the decision-making problem needs a hybrid procedure. To overcome this matter, the hybrid projection measure is extended to obtain the experts weights and build the aggregated decision matrix. In the RCPSP section, the activities durations are not determined and vary between certain ranges. The resource requirements and range of activities durations are obtained from group decision-making method. In addition, this model is solved with simulated annealing (SA) algorithm. In the third step, buffers are considered in a way that allocating project buffer to activities’ buffers becomes based on a new normalized important factor. The normalized important factor is introduced by considering activity duration and resource requirements. Finally, a novel controlling procedure is extended by activity buffer monitoring. Two buffer threshold sets and violations are applied, and each one of them sends a particular alarm to the project manager. Project manager’s decisions in optimistic and pessimistic situations are discussed. Ultimately, the method is solved in a real case study, and the results are discussed. The application shows that the presented method is flexible in many situations. It also increases the probability of timely completion of the project in addition to tracking the deviations from the plan. The proposed method introduces a comprehensive framework, so it gives project managers a better vision. It can also act as an ideal monitoring tool to control schedule deviations and to help project manager for proper actions during the project execution. © 2020 Elsevier B.V. All rights reserved. 1. Introduction Projects failure is an inherent part, but in project-centered organizations, this failure is more significant [1]. Projects will be facing increasingly complicated challenges for the next decade. These conditions have existed before, but not by today’s charac- teristics. Project management mainly deals with initiating, plan- ning, executing, controlling, and closing the work of a team to reach specific goals success criteria at the specified time [2]. Project scheduling since the late fifties has received a lot of attention in the research area. Project scheduling is mainly con- cerned with assigning activity starting times based on scheduling ∗ Corresponding authors. E-mail addresses: sm.mousavi@shahed.ac.ir (S.M. Mousavi), edmundas.zavadskas@vgtu.lt (E.K. Zavadskas). objectives, like minimum project duration and minimal project cost [3–5]. One approach in scheduling is a resource-constrained project scheduling problem (RCPSP), which has been the focus of many scholars and is an essential issue in project management [6]. In the traditional method of RCPSP, activities are often scheduled with the goal of minimizing the total makespan of the project. However, the classical RCPSP model is not enough to show all aspects of the real world. So, many extensions have been pro- posed for the problem, such as min/max time lags, multi-mode, multi-skill, etc. [7]. In classical RCPSP, the objective is to minimize the makespan, and constraints are mainly about the precedence of activities and resource constraints [8]. By considering the complexity of the problems, the design of an efficient algorithm to solve a problem https://doi.org/10.1016/j.asoc.2020.106915 1568-4946/© 2020 Elsevier B.V. All rights reserved.