Integration of linear scheduling method and the critical chain project management

Abstract

Scheduling of construction projects can be categorized into repetitive and non-repetitive. 47Repetitive scheduling contains cycles of repetitive activities such as those encountered in 48 housing units, highways, pipelines, and railways. Non-repetitive scheduling (network 49 scheduling) fits construction projects that do not require continuity of resources. These two types 50 of scheduling are also referred to as activity-based network scheduling and location-based Method 118The proposed method integrates CCPM and LSM; the aggressiveness of CCPM leads to shorter 119 schedules while LSM visualizes repetitive processes and accounts for continuity of resources. 120The framework of proposed method is illustrated in Figure ( 129Calculation of aggressive and safe durations using CPR leads to identification of the controlling 130 resource for each activity as presented in Equation (3). The controlling resource is defined as the 131 resource that controls the activity duration. Where, 138D i, j (AG), represents the aggressive duration of activity "i" in process "j". 139CPR i (CL), represents constrained productivity rate of activity "i" with resources availability at 140"CL" confidence level. 141CPRi (AG) represents constrained productivity rate of activity "i" with resources availability at 142 50% confidence level. Sequencing activities based on aggressive durations (average schedule):144The aggressive schedule is sequenced using illustrates the developed procedure for maintaining the continuity of resources. Russell and continuity of work for all activities "i" in the same process "j" as well as the continuity of work 160 among consecutive processes using Equations (4) and (5). Equation (4) calculates the SD of an 161 activity "i" as the maximum between the finish date (FD) of same activity "i" in preceding 162 process "j-1" and the FD of its preceding activity "i-1" in the same process "j" to maintain 163 continuity in the same process as well in the consecutive processes. Equation (5) calculates the 164 FD of activity "i" in process "j" as the sum of SD ij calculated using Equation (4) and the duration 165 of activity "i" in process "j" calculated using Equation (1) and (2). As long as "j" remains 166 smaller than the total number of processes (m), this procedure is repeated for all activities "i" in 167 all processes "j" to maintain the continuity of processes in the developed linear schedule. However, the continuity constraint in linear scheduling should be respected. If two or more 179 sequential activities share the same controlling resource, then the priority is given to predecessor 199QC: Resources quantities consumption during normal duration in preceding activity. 200O RC : Overlap due to resources conflicts. 201The variability of resource for preceding activity shifts the start of the succeeding activity by Where, 210O VAR : Overlap of resources quantities variability for preceding activity. 211Q 50%: quantities in preceding activity with 50 % confidence in availability. 212Q 90%: quantities in ...

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