With the progress of science and technology and the development of society, the construction industry is moving towards the direction of large-scale and intelligent. There are more and more projects with large volume, many types of work, high technology and difficult construction, so higher requirements are put forward for the management mode. The embedded system based on ARM microprocessor and radio frequency identification (RFID) technology is widely used in production, transportation, logistics, transportation, tracking, asset management and other occasions. The application of this technology in large-scale construction site management can achieve electronic, network, scientific and technological fine management.
1. Overall structure of intelligent management system for construction site
Radio frequency identification (RFID) is a kind of non-contact automatic identification technology rising in the 1990s. It uses radio frequency signal for non-contact two-way communication, so as to automatically identify the target and obtain relevant data. RFID technology has the advantages of high precision, environmental adaptability, strong anti-interference ability and convenient operation.
Embedded system is the embedded computer system, its application can be roughly divided into two categories: one is the intelligent electronic system, such as industrial control, modern agriculture, household appliances, automotive electronics, measurement and control system, etc; The other is the extension of computer applications, such as MP4, mobile phone, communication, etc.
The large-scale construction site intelligent management system is an application combining 32-bit ARM embedded processor with RFID technology. The system is mainly composed of electronic tag and card reading system, arm development board, computer service system, etc. RFID technology is used to achieve information acquisition for each individual. RFID system consists of card reader, electronic tag and upper application software. The embedded system uses the on-chip resources of ARM chip to realize the functions of card reading, display, alarm, monitoring and communication. Arm controller can be developed by STM32 series of STM32 and mcf5223x series of Freescale. Many RFID companies have supporting products, such as domestic Shenzhen Yongdao company, DELISON company, and foreign Gabriel company.
The electronic label has paper type, card type, etc. the shape can be designed according to the requirements. When the object with the tag is close to the card reader, the information code is read out by the RFID system, and the arm controller processes the information and makes the corresponding control. The information is transmitted to the upper computer through network communication, and the data is stored and managed by the upper management software. If connected to the Internet, the source information of materials can be traced. The overall structure of the intelligent management system is shown in Figure 1.
2. Adopt RFID intelligent security management system
2.1 improve safety measures and speed up construction
There are many subcontracting projects in construction engineering, involving civil engineering, mechanical and electrical installation, decoration engineering and steel structure. There are many people involved in each entry and exit, and all kinds of vehicles transport frequently. RFID technology has the ability to identify high-speed moving objects. The RFID card or key tag is distributed to the construction personnel and vehicles for use in and out of the construction site. When the personnel and vehicles are about to arrive at the gate of the construction site, the card reader fixed at the gate will immediately obtain the information and transmit it to the arm control center, and the upper computer will compare it and automatically release it after confirmation. The use of non-stop access management reduces the workload of the guard, greatly shortens the access speed of transport vehicles, and speeds up the construction process. Because the intelligent security system of RFID can read the card at the same time, and has the ability of anti-collision, it is not easy to make mistakes. It only needs to be equipped with a guard to be responsible for the overall planning. At the same time, RFID tracking system is used to record the arrival and departure of trucks. Users can quickly understand the progress and efficiency of the project.
The intelligent security system based on arm and RFID can adopt the monitoring modes of “RFID + fingerprint identification”, “RFID + camera”, “RF + fingerprint + camera” and so on. When the problem person passes by, the alarm will be triggered.
2.2 RFID technology for material tracking and single piece management
RFID technology can realize non-contact reading without wear, and the service life of the electronic tag can be as long as 10 years, and the reading and writing times can reach 100000 times. The RFID tag can be expanded to tens of kbit according to the needs of users. And the data in the tag can be updated, and the barcode is read-only, which can not be changed once printed. Therefore, the RFID system’s electronic tag is suitable for storing a large amount of data or the data stored on the item needs to be changed frequently. For the materials on the construction site, the whole batch can pass through the reader area at the same time. When collecting the relevant information, there is no need to use the bar code technology to split and sort them, and then enter them one by one. At the same time, an electronic label can also be pasted on a single material. For example, an electronic label can be pasted on a certain steel bar. The card reader can display the manufacturer, production batch and quality inspection of the steel bar, thus saving human resources. When the information enters the background server, you can input the direction of the steel bar in the information database.
Large scale construction projects involve many kinds of projects, material types, material batches, and complicated asset management and file management. RFID technology is used to manage materials, mark and monitor valuables, detect tampering or unauthorized actions, so as to control management and reduce costs. Ensure accurate and timely delivery, avoid unnecessary trouble or extra workload. At the same time, strengthen the
Supply is in line with project planning to reduce labor costs and avoid penalties for violations throughout the project. Reduce the buffer stock of the factory and construction site, deal with the goods defects and various claims in time.
2.3 RFID technology for construction site process management
The quality of construction is related to personal and property safety. From material procurement to engineering construction to final quality inspection, the whole process requires a lot of information management, so the amount of data storage is large, and RFID technology meets this demand. Through radio frequency identification for massive data collection, and then by the background computer management.
RFID technology can also realize the information management of unformed materials. For example, concrete materials can not only record the specific value of each batch of mixing proportion, but also embed active RFID tags and temperature sensors in concrete, so as to easily and accurately monitor the curing process. After solidification, the inspectors read out the information code through the handheld card reader, and the background server obtains the concrete solidification data for the information code, including the manufacturer, qualification certificate, safety certificate, production date and production quality. Compared with the traditional management mode, this method saves time, and uses the uniqueness of each RFID tag number to identify, so as to create reports and carry out statistical analysis.
In the increasingly competitive environment of the construction market, the management system supported by RFID technology can explain the construction quality through data, and eliminate the enterprises that ignore the quality and reduce the cost. At the same time, using this technology for construction site process management can strengthen and improve the visibility and transparency of construction project participants to the supply chain, so as to obtain more accurate information flow.
2.4 using RFID technology to quickly identify the cause of the accident
RFID technology is used to purchase in the early stage, build in the middle stage, and manage in the late stage in a clear and detailed way. Huge data are stored in the background server and can be called at any time. After the building is put into use, once the collapse or leakage occurs, the cause can be quickly determined by looking up the data. For the buildings with electronic tags reserved, due to the long service life of electronic tags, data information can be obtained on site by holding a card reader with communication function and display screen.
In addition, RFID can track assets, ensure the security and maximum utilization of valuable assets, and reduce the risks of builders and contractors. RFID can also realize scheduling service, and the maintenance information stored in RFID tags automatically matches with the corresponding machines and equipment, so as to ensure that each machine or equipment can be maintained accordingly.
The RF equipment system based on arm has the characteristics of few components, strong function and high reliability. Using RFID technology to manage large construction sites can maximize the efficiency of construction workers and the utilization of construction resources, and analyze, classify and count the basic data collected in the process of material transportation, which greatly improves the work efficiency and saves manpower and time. It is the development direction of the future construction industry.
Editor in charge: CT