Rose Roofing Canada, the concept of scheduling is the conversion of the action plan of a project into a timetable for the various operations involved in that project. This section is the basic section for monitoring and controlling a project, especially construction projects. In this schedule, the start and finish times of each project activity along with the relationship between them are determined graphically.
To prepare this schedule, the project is divided into a number of smaller parts and the cost and time of each operation is calculated based on the amount of work. Considering the complexity of the work, it is always recommended to prepare the schedule by a knowledgeable person who has sufficient experience in the field of the project. This has caused the use of computer software in this matter to increase day by day. Of course, it should be noted that the software may be an effective help in lining up activities, keeping in memory and implementing corrections, but one of the essentials of a professional schedule is creativity, which justifies the need for an experienced and creative engineer. to do In general, scheduling along with budgeting are the most important management tools and without them, it is not possible to complete the project in the expected time and cost.
Basics and advantages of scheduling
The start time of each activity is specified. Therefore, before starting the activities, you can spend enough time to prepare the required materials.
The relationship between all tasks and elements of the project is clear.
Monitoring and control of the project is greatly facilitated with the help of the schedule.
By identifying the critical path after creating a delay in any of the activities, the project time is delayed. But the point is that the project time will be known after applying the delays.
It is possible to allocate resources and align them.
The effects of changes caused by errors or weather conditions can be evaluated and the program can be changed appropriately if necessary.
Steps to prepare the schedule
To prepare a suitable schedule, the following steps must be taken. Accuracy in performing these steps reduces the amount of change in this program during the project.
Steps to prepare the schedule
1- Determining the activities: The first step in preparing the schedule is to identify and list the activities of the upcoming project. Different tools and technologies are used to determine the activities. One of the methods is Decomposition. In this method, project work packages (Project Work Packages) are divided into smaller components, i.e. activities. In various references, this issue is known as WBS. This division facilitates planning, implementation and control.
But there is another method to determine the activities and that is the template method. The advantages of this method include saving time and reducing the possibility of ignoring some activities. In this method, the information of past projects in WBS is used.
2- Determining the sequence of activities and sorting them: Identifying and documenting the sequence of activities and determining the logical connection between them plays an important role in the success of a schedule. In this section, we refer to the types of logical relationships between activities.
Previous and next relationship: An activity should start after the completion of the previous activity. Like the construction of the column, which is done after the stabilization of the pit and the implementation of the foundation.
Mandatory communication: An activity must start after the completion of the previous activity and this communication is mandatory. For example, you cannot start the construction of the column before the foundation is finished.
Precautionary communication: This is the communication that is preferred by the project manager or team. For example, the project manager decides that the north pier of a bridge should be installed before the south pier.
However, arranging the activities should be logical, acceptable and possible, and this requires sufficient experience and a correct understanding of the implementation of different activities.
3- Estimating the time of activities: In this step, the duration of each activity is estimated. The duration of the activities can be estimated in terms of hours, working days, calendar days, weeks, or months. In construction projects, depending on the type and conditions of the project, activities are estimated in terms of working days or calendar days. The following factors are involved in this estimate and can change the duration of an activity:
Contract terms
Type and amount of work
Construction method
Environmental and climatic conditions
Project time limit
Type and amount of resources
Number of work shifts
Effective factors in the time estimation of activities in construction projects
4- Scheduling: arranging the activities according to their sequence and connection, analyzing the times of events and activities and finally determining the duration of the project at the end.
From the point of view of PMBOK, in project time management, there is a step other than the above steps under the title of type and amount of resources. Although the estimation of resources is very important in estimating the cost and budget of activities, it is not necessarily used in preparing the schedule. But it is necessary to point out one point, and that is regarding the estimation of resources. When the initial schedule is prepared, it should be reviewed according to the allocation of resources so that the necessary corrections are applied to it. In this review, resource alignment and existing resource constraints play an important role in schedule reform.
Cost estimation and project budget
It can be said that the budget estimation of a construction project plays the most important role in the management process of that project, because the wrong estimation will increase the probability of risk in the project and, in most cases, will lead to a decrease in the quality of the project. In fact, schedule and budget are two factors that help each other to measure and control the progress of the project. There are different methods to estimate the budget, which are briefly described below.
Parametric estimation
In this estimate, a mathematical model is used to communicate the cost to one or more variables. This mathematical model is usually obtained with the help of data obtained from the past and the use of statistical tools. This mathematical function can be linear or non-linear. Usually, parameter estimation is used in the project definition phase, which is considered the initial phase of every project. The accuracy of this method is between -30% and +50%.
Estimation of similarity
In this estimate, the estimates of a similar project are used. The application of this method is the same as the parametric method and its accuracy is between -10 and -25%.
Bottom up estimation
In this estimation, the cost estimation of different activities is done independently. Finally, by adding up the cost of each activity, the desired estimate for the project cost is calculated. This method is only possible when the design phase of the project is completed. The accuracy of this cost estimation method varies between -5 and +15%.
Definitive estimate
The definitive estimate itself is considered a kind of bottom-up estimate and is done when the project design is done and its plans are known along with all its technical details. The accuracy of this estimate is ±3. The difference between this cost estimate and the bottom-up estimate mentioned above is that it is much more accurate due to the presence of all the details.
Read more in the field of buildings and construction:
Building & Structure
Construction participation contract
Construction Supervision
What is a shed? Types and applications of industrial sheds
Management Contracting
Construction Management
Types of structural systems (Structural System)
Management of construction projects (Project Management)
2800 regulations, design of buildings against earthquakes
Steel Structure
Concrete Structures
Read more about pit stabilization:
What is top-down or top-down construction? (Top-Down Construction)
What is nailing or wall nailing? (Soil Nailing)
What is soil anchorage? (Soil Anchorage)
What is mutual inhibition or strat? (Braced Excavations – Struts)
What is a truss guard structure? (Truss Retaining Structure)
Read more about soil improvement:
What is high pressure injection or jet grouting? (Jet Grouting)
What is Deep Soil Mixing or DSM? (Deep Soil Mixing)
Read more in the field of geotechnical studies:
What are soil studies or geotechnical studies? (Site Investigation)
What are seismic studies? (Seismic studies)
Read more about design and consulting:
Introduction of SAFE software
Introducing SAP2000 software
Introduction of Plaxis software
Introduction of ABAQUS software
Read more about demolition and excavation:
Destruction Engineering
What is excavation? (excavation)
){kind=link}
No comment