نشریه علوم و فنون سازندگی
سال سوم شماره 2 (پیاپی 8، تابستان 1401)

Masonry walls are one of the main load-bearing elements against lateral forces. Because brick walls and vertical and horizontal beams in this type of buildings are used as a support for the roofs and to withstand gravity load and also as a shear wall to withstand seismic load. These methods also include reinforcement using FRP fibers, fiber-reinforced concrete and shotcrete. One of the most important methods of strengthening this type of walls, which is considered due to climatic conditions and the production of materials in Iran, is the use of brick wall reinforcement using surface concrete, which has been the subject of several laboratory studies. . In this research, the numerical study of coiled masonry wall reinforced using surface concrete and steel belt network as one of the methods of masonry wall reinforcement using finite element method has been investigated. Therefore, in this research, by numerical modeling of six samples of coiled masonry wall using finite element method by ABAQUS finite element software, three samples as reinforced masonry and three samples as reinforced masonry have been subjected to increasing load. . By examining the method of strengthening the masonry wall reinforced with surface concrete, the capacity as well as the ductility of this type of wall will be evaluated and compared with unreinforced samples.

In recent years, vibration-based damage detection has been used to assess damage to structures. In this case, damage detection is based on changing the dynamic response before and after damage. In this research, the flexibity matrix method has been used to identify damage in segmental bridge (Imam Khomeini intersection bridge). The advantage of this method is its accuracy and sensitivity to a small number of modes for large structures. The bridge was simulated in Abacus software and after applying weight and prestressing force to the cables, the frequency and modal shapes were extracted for healthy and damaged conditions. Damaged conditions included three scenarios, single (in one place) and multiple (in several places and simultaneously) on the bridge deck as well as damage to the column. Each of the above damages involved a 30% reduction in stiffness. The results showed that this method was able to detect damages in the deck. But more investigation was needed to monitor the health of the column. The accuracy of health monitoring was also assessed using two modes, which had acceptable accuracy compared to the use of 6 modes.

In this work, a system for troubleshooting solar panels is designed and built that is able to monitor the performance of solar panels in a solar power plant on a daily basis and provide the user with the production information of the panels in the form of diagrams and numbers. Graphs and colors have also been used for the convenience of the user in reading the information and status of the panels. The designed system consists of a hardware part and a software part. In the hardware part, the system reads current and voltage information from the terminal behind the panel and sends it to the center via the LORA connection. In the information center, all the information is sent to the computer by the radiation intensity sensor of the system while reading the radiation information. The software part of the computer, written in the Python programming language, takes the information from the user and reads it according to the reporting time that the user sets. The software has the ability to display panel information in color and diagram and records daily information at the end of each day so that the user can access them at any time.

 In mechanized tunneling of soft grounds with boulders, several types of cutting tools are used on the cutter head of the machine. The main cutting tools used in this condition are rippers, disks or a combination of them. In the tunnel of the eastern part of the Mashhad urban railway line 3 project, due to fine grain layers the tunnel section, the main tools used were the rippers. The discs were used only in the cutter head gauge. The addition of a gravel layer containing boulders in the tunnel section has reduced the durability of the rippers and increased the specific excavation energy up to 25%. In order to increase durability, NFM designed rippers were replaced with heavy rippers. In addition, various alloys have been investigated by test and error method. Changes in dimensions and alloy increased the durability if the tools up to 37%. By replacing the NFM designed rippers with heavy rippers, the performance of the rippers have increased from 183 meters to 250 meters. The result of tool replacement in the eastern part of Mashhad urban railway line 3 (about 10 km from the route) shows that the consumption of cutting tools in the boulder area was 10 times the area before the collision with the boulder. In general, 280 tools have been replaced in the investigated boulder area (about 1.7 km), which has resulted in saving about 60 billion rials by using heavy rippers instead of NFM rippers.

Nowadays, different Remote Sensing methods are one of the most practical methods in the field of mineral exploration in mountainous, border areas and without valid geochemical samples and waterway sediments in recognition phase. Spectral methods such as Mixture Tuned Matched Filtering, Spectral Angle Mapper and Linear Spectral Unmixing. The spectrum of each pixel in the image identifies different effects. This study was conducted to determine the areas of alteration, separation of different rocks and minerals, classification of images and finally to determine high potential areas of Ophiolite mineralization, Serpentinites, serpentinized harbors, Listvenites, Chromite and Manganese in Siahcheshmeh and Dizajj areas. In the processing stage, the new Automated Spectral Hourglass method based on spectral methods has been used in order to determine the altered areas and separate the minerals. In order to classify the images, Deep Convolutional Neural Network (CNN), Support Vector Machine (SVM) and Decision Tree J48 (DT) have been used. Finally, the performance of different models was compared based on different evaluation criteria and the CNN model with 98% accuracy compared to the two SVM and DT models with 96% accuracy has been used as the best model for preparing the classification map.

Due to the lack of renewal energy and the problems they have for the environment, the use of clean energy such as solar energy, especially clean and green fuels such as biodiesel, is of particular importance. In this study, the laboratory was designed and manufactured by the solar biodiesel system, which used two solar flat plate collectors to heat the raw materials of biodiesel, mixer, copper coil, pump and stane chamber. It was used to measure the temperature from 4 temperature sensors for the 16 -channel database that requires Arduino software 1.8.5. One of the factors contributing to the increase in the efficiency of the laboratory cycle and the production of biodiesel is the sun's radiation, during which the temperature passed from two collectors to 75.12 degrees Celsius, in which the temperature reacts faster and results in fuel production. Proper and complete insulation of the cycle causes no heat exchange with the outside environment and increases the efficiency and product of the production.