Critical Chain Project Management Method Research Articles

Review Kapasitas Daya Dukung Dan Tinjauan Waktu Pelaksanaan Bore Pile Pada Pembangunan Jembatan Jalan Bebas Hambatan Binjai Pangkalan Brandan

In the Sei Wampu Bridge work project, Binjai Pangkalan Brandan carried out bore pile foundation installation work at the A2 foundation point with a total of 21 piles. Review of the bearing capacity of bore pile foundations using Analysis from Meyerhof (1956) and the Converse-Labarre Formula method for the calculation of pile group efficiency. The time of completion of work based on the time schedule plan is 125 calendar days. This research conducted a review using the Critical Chain Project Management (CCPM) method to obtain time efficiency, so that the project can be carried out on time.
 From the results of analysis and discussion, it was obtained that the largest foundation carrying capacity was the result of laboratory data using method C. Significant differences in results were obtained, especially laboratory data due to the correlation value used in each method. The result of calculating the bearing capacity of the foundation based on the method of Luciano Decourt (1987) using N-SPT data is 287,600.76 kN; Meyerhof's (1956) method using N-SPT data is 265,062.68 kN; a combination of Meyerhof's method (1976), Vesic's method (1977); the combination of the Vesic method (1977), the Coyle and Castello method (1981) and the results of foundation carrying capacity analysis using the All Pile program is 41,159.85 kN.
 The Critical Chain Project Management method is defined as the longest chain of interrelated events, where the linkage lies in the work or resources that are interconnected with each other, by cutting 50% of the duration of the work and replacing it as a buffer. The time comparison obtained from the calculation results using the CCPM method obtained a time efficiency of 116 days with a work time difference of 7.2% or about 9 days from the existing duration of the previous 125 days, while to compare the results of the CCPM method, calculations were carried out based on realization for 97 days, where the realization results were smaller than using the CCPM method and time schedule plan.
 Keywords : Bore pile, Carrying capacity, Time review

Productivity Analysis Using the Critical Chain Project Method Management (CCPM) on Repair Projects Geomarin-III ship 649 DWT.

Ship repair project planning still often encountered problems that delay ship repair projects to achieve complete ship repair projects. Delays are due to frequent mismatches between ship repair scheduling and conditions that occur at the shipyard. The most commonly used method is the Critical Path Method (CPM). But in reality, the CPM method is considered less effective because there is still safety time for each job. Technological developments found the latest method, namely Critical Chain Project Management (CCPM). This method removes the safety time contained in the CPM method and replaces it with buffer time which is placed at the end of work activities. This study aims to analyze the duration of the critical path, determine labor costs, and the amount of buffer duration on the repair of the Geomarin-III 649 DWT ship. Based on the calculation results obtained on the repair of the Geomarin-III 649 DWT ship with the Critical Chain Project Management (CCPM) method is 10 days, 10 days faster than the normal duration. The labor cost obtained using the CCPM method is IDR. 54,017,500, saving 35% of the normal cost is IDR. 82,680,000, but if the buffer time is used thoroughly, the total estimated labor cost for the CCPM method will increase due to the addition of labor and the duration of the buffer time obtained by the CCPM method as a substitute for safety time, which is 9 days project buffer and 3 days feeding buffers. Based on this research, it was found that the CCPM method is considered effective and can accelerate the duration of the project and minimize labor costs.

Perencanaan Proyek Struktur Semi Gantry Crane Menggunakan Critical Chain Project Management

Project completion work has problems related to project completion not being on time, thereby increasing costs and resources. The work on the gantry crane structure includes projects that experience problems related to incompatibility between project planning and actual project work. This study aims to plan project activities by speeding up processing time and providing prevention strategies to minimize project delays. This study uses the critical chain project management method using the cut & paste method by 30%. The results showed the total buffer time was ten days, consisting of eight project buffer days and two feeding buffer days. The total time for the semi-gantry crane structure project has accelerated from 43 days to 33 days. Suggestions for prevention that can be done to complete the project according to the plan are adding project workers, adding tools or machines, and eliminating multitasking activities that cause project workers not to finish their work immediately.

Comparison of PERT/CPM and CCPM Methods in Project Time Management

Purpose: Evaluate and compare PERT/CPM and Critical Chain Project Management (CCPM) techniques, from the Theory of Constraints (TOC), in relation to indicators of delivery time estimation and reliability in meeting established deadlines.Theoretical framework: The research is based on the time management theory established by the PERT/CPM and CCPM methods.Design/methodology/approach: This work has an experimental character, using a method of computer simulation by applying the Promodel software. A fictitious project environment managed by PERT/CPM and CCPM techniques was modeled in order to evaluate and compare their performances in terms of estimation of, and compliance with, project completion deadlines.Findings: The results obtained showed that the CCPM method proved to be more effective in reducing project completion time and meeting established deadlines. Conversely, the PERT/CPM method increased planned project completion time by 189%.Research, Practical & Social implications: Many managers assume that the best approach to project planning, especially when aiming for short and reliable deadlines, is to allocate margins of safety to each scheduled activity. This research reinforced the already widely held perception of TOC that, due to certain ordinary human behaviors, local optimizations do not guarantee, and usually adversely effect, good global results.Originality/value: There is a lack of research comparing PERT/CPM and CCPM techniques through modeling and computer simulations of project environments subjected to certain degrees of uncertainty, particularly in terms of performance variables such as those studied here. The results of this research, therefore, address this opportunity, bringing to light comparative scenarios and explanations for the different behaviors observed.Keywords: Computational Simulation; Project Management; Goldratt; Critical Chain; CCPM; PERT/CPM.

Analysis of Time Efficiency with CCPM Method and BIM in Construction Projects Construction of High-Rise Residential Building Basement

Development in Indonesia is experiencing a rapid increase, a lot of vacant land is used by investors to construct buildings. The implementation of the construction must pay attention to the project schedule, work delays often occur. The factors that cause work delays are usually from weather disturbances, delivery and supplies of materials and tools that are not in accordance with the plan, changes in design and other external, internal factors. For this reason, this study will discuss about controlling project time using the critical chain project management (CCPM) method and 4D building information modeling in high-rise residential building projects, especially in 5-layer basement work. The critical chain project management method eliminates safe time and replaces buffer time. Adding buffer time using the cut and paste method, namely adding a project buffer half the duration of the critical chain (critical chain) at the end of the chain and placing the feeding buffer with half the activity duration to activities on the non-critical chain. Delays in the construction of a 5-layer basement usually include changes in the level of soil surface conditions, the stability of the excavated soil during the secant pile excavation period as a retaining wall as deep as -17,350 m below the ground level. The results of this study can optimize the duration of the implementation with the final completion time of the structural work faster than 432 working days to 293 work days of implementation so that the time efficiency is 32,17%.

A DSM-Based CCPM-MPL Representation Method for Project Scheduling under Rework Scenarios

Rework risks caused by information flow interactions have become a major challenge in project scheduling. To deal with this challenge, we propose a model integrating the critical chain project management method, design structure matrix method, and max-plus method. Our model uses a start-to-start relationship of activities instead of the traditional finish-to-start relationship, which also allows overlaps between activities. We improve the accuracy of the rework safety time in two ways: (1) the overall overlapping effect is taken into consideration when calculating the rework time of an activity arising from the information flow interaction of its multiple predecessors overlapped with it; (2) the rework time arising from activity overlaps, the first rework time, and the second rework time are calculated as components of the rework safety time in our model, while the last one is ignored in traditional methods. Furthermore, the accuracy of time buffers is improved based on the improved rework safety time. Finally, we design the max-plus method to generate project schedules and appropriately sized time buffers. The empirical results show that the project schedule generated by the proposed method has a higher on-time completion probability, as well as more appropriately sized project buffers.

Scheduling evaluation in construction projects using the critical chain project management method

PT. A is a company engaged in construction, EPC (Engineering, Procurement and Construction), infrastructure investment, property and real estate. The case study that was raised in this study was the construction project of the retaining wall and the ABC dock that was carried out by PT. A. The problem in the project is that the project scheduling is not good, causing delays in project completion. The purpose of this research is to evaluate the scheduling of the project so that the optimum schedule can be obtained in project implementation. The method used in this study is Critical Chain Project Management (CCPM). CCPM is a project scheduling method that can optimize the schedule due to the absence of multitasking. The CCPM begins by estimating the time without safeguarding the existing time on each job by using the Cut & Paste Method. The critical path serves to find out the critical or non-critical work or activity. Critical activities on wall construction projects anchoring land and ABC dock namely work keep directors. Based on buffer consumption monitoring indicators due to the potential for the emergence of waste will end in use of project buffer duration consumed during the 19-35 period day and immediately take action if the buffer is consumed in the period of 36-53 days. Based on evaluation with critical application Project chain management obtained one feeding 4-day buffer and duration of the buffer project 53 days with the existing scheduling period 432 days to 379 days without buffer consumption.

Scheduling of an assembly process of a chosen technical mean using the critical chain approach

In the work is presented the CCPM (Critical Chain Project Management) method that differs from other network approaches. The differences are related with: the scheduling process, with restrictions of the project that are taken into account and with the time buffers allowing avoiding delays in realized tasks. Each project should be such organized to effectively achieve the previously assumed goals. The paper presents all the steps involved with utilization the CCPM method for determining the schedule of an assembly process of a mining shearer machine. It is presented the elaboration of the network of tasks and preparation the process schedule. It is also realized the resource optimization and the safety buffers introduction.

Estimation of the resource buffers in the assembly process of a shearer machine in the CPPM method

Dynamic development of scheduling systems allows significantly improving currently realized tasks. Critical Chain Project Management (CCPM) is one of the methods of project management basing on network planning. In this method is utilized the concept of a critical chain derived from the Theory of Constraints. This method allows avoiding losses considered project time and resources. It results in quicker project implementation (20-30%), and in reducing the risk level considered with tasks realization. The projects are cheaper, and the risk of cost overruns is significantly reduced. Factors that distinguish CCPM method from traditional network planning methods are: the balance of resources and the introduction of buffers. Moreover in the CCPM method key elements are: times of tasks that are reduced from traditional estimates to realistic ones. Activities associated with the task start as late as possible in accordance with the ALAP principle (As Late As Possible). This work presents the process of managing the assembly of a shearer machine taking into account the process of safety buffers utilization and the whole project optimization. It is presented the estimation of buffers capacity to obtain the improvement of project realization task.

Location Selection and Size Estimation of Resource Buffers in the Critical Chain Project Management Method

Critical Chain Project Management (CCPM) is based on a network planning and the Theory of Constraints. The importance of management of uncertainty and deviations that occur during a project is emphasized. The probability of the project completion in a predefined time limit, or even before the time limit is increased. Literature analysis indicates that other types of buffers must be applied (buffer supporting a project, buffer reacting on a critical path, buffer reacting on a non-critical path) apart of feeding, resource and project buffers. Applying the additional buffers keeps the critical path in the same position and maintains the unchanging due date of the project. Methods estimating size of feeding and project buffers are identified: half of the chain method, square root of fault method, modified method of square root of fault, method taking into account due date of the project. In this paper, a new method estimating a size of resource buffer and selecting a location of resource buffer based on the theory of probability is presented. In this paper, the CCPM method is applied to estimate due date of the mining machine production project.

BUFFER SIZING FOR THE CRITICAL CHAIN PROJECT MANAGEMENT METHOD

Methods for sizing project and feeding buffers for critical chain project management are investigated. Experiments indicate that – in the absence of bias, and for certain classes of bias – buffer consumption is independent of the mean duration of a chain. Generally the popular method – a buffer size equal to 50% of the longest path leading to it – gives rise to excessively large buffers. Buffers sized according to the square root of the sum of squares perform well in the absence of bias, but with bias present the performance is unacceptably poor. A new approach to buffer sizing is proposed. OPSOMMING Metodes vir groottebepaling van projek- en saamvloeibuffers vir kritieke-ketting projekbestuur word ondersoek. Eksperimente dui daarop dat – in die afwesigheid van onewewigtigheid, en vir sekere tipes onewewigtigheid – bufferverbruik onafhanklik is van die gemiddelde lengte van ’n ketting. Oor die algemeen veroorsaak die metode van buffergrootte – gelyk aan 50% van die langste pad wat tot die buffer lei – onnodige groot buffers. Buffers bepaal met die metode van die vierkantswortel van die som van kwadrate, vaar goed in die afwesigheid van onewewigtigheid, maar vaar onaanvaarbaar swak wanneer onewewigtigheid teenwoordig is. ’n Nuwe metode vir die bepaling van buffergrootte word voorgestel.

Critical Chain Project Management Based on a Max-Plus Linear Representation for Determining Time Buffers in Multiple Projects

We propose a framework for describing the Critical Chain Project Management (CCPM) method based on a Max-Plus Linear (MPL) representation for multiple projects. The framework takes into account time buffers in both a single and multi-project environments which play a role for controlling undesirable state change and protecting the completion time for the entire system. The appropriate position and size of these buffers are determined for a large scale multi-project system. Furthermore, the MPL system with the CCPM method applied is redefined to easily comprehend the structure of the system. Finally, we confirm the proposed framework through a numerical example.

Resource Allocation Optimization in Critical Chain Method

The paper presents resource allocation optimization in Critical Chain Project Management (CCPM). The cheapest project schedule is searched with respect to time constraints. The algorithm originally developed for the hardware-software co-design of heterogeneous distributed systems is adapted to work with human resources and CCPM method. The results of the optimization showed significant efficiency of the algorithm in comparison with a greedy algorithm. On average, the optimization gives 14.10% of cost reduction using the same number of resources. The gain varies depending on the number of resources and the time constraints. Advantages and disadvantages of such an approach are also discussed.