# Interoperability of Digital Tools for the Monitoring and Control of Construction Projects
## 2 Background
### Traditional Construction Monitoring and Control System  
The planning and control of a project is one of the key processes for the adequate development of the project and the success of each of its phases during its life cycle. Appropriate planning allows for the explicit definition of the work to be done, risk identification, consideration of different scenarios and the attainment of solutions. Adequate control offers the possibility of detecting deviations, informing on time the anomalies, allowing for their correction and ensuring the quality of a project [14]. Establishing a system to ensure the correct execution of the work is fundamental and must be adapted to the nature of each project and its environment. For this reason, there are different methodologies to carry out project management, that is, the application of knowledge, skills, tools and techniques to the activities of a project to comply with its requirements [17]. According to some studies, control tasks using traditional methods generate difficulties for information management caused by imprecise manual documentation and deferred data collection, which leads to delays in decision making [18]. It is common that a lack of opportune information about the actual state causes problems to remain unresolved and prevents field engineering staff from solving them in an opportune amount of time. An incorrect understanding of the current situation can cause errors and inappropriate adjustments by the management team, which could result in further delays and increased costs [19]. The set of monitoring and control activities consists of the processes required to monitor, analyze and regulate the progress and performance of a project, to identify areas where the plan requires changes and to make the corresponding modifications [20]. In this sense, because of the dynamism in a project, maintaining daily control can have a considerable impact, providing greater precision around the schedule and costs to comply with the scope defined in the project [21]. To carry out progress control, it is fundamental to have a work program to know when, with what and how the works will be executed. During the construction phase, it is relevant to know if the work is being performed according to the established schedule. An accurate evaluation of progress allows project managers to make adjustments to minimize costs that lead to program deviations [10] (Figure 1). Figure 1 shows a schematic of a model for real-time closed loop control. In this model, it is necessary to establish a control system that can regularly keep project managers informed of the progress made in each activity. In the case of delay or deficiency in any activity, this system enables time-sensitive corrections, either by increasing the number of workers, changing the equipment or correcting the work program. If it is verified in an opportune way that there was a planning mistake, and it is possible, although with modifications, to maintain the original program, then it will be possible to fulfill the  
Figure 1: Schematic of model for real-time closed loop control. Adapted from [22]. delivery terms. If these corrections are not made on time, it is difficult to continue with the initial project schedule, and a new plan will have to be constructed, whose application will certainly mean disorders and greater project costs [23]. Therefore, the objective of monitoring is to ensure compliance with the objectives and goals proposed by the plan during its implementation, alerting any difficulties and relieving pending or delayed tasks, and allowing visualization of complementary actions by making the necessary adjustments. It is worth noting that for the monitoring of a plan, it is necessary to establish methodologically how information about projects and management measures will be obtained to understand the plan's progress and facilitate its control.