نشریه مهندسی آب
سال دهم شماره 3 (پاییز 1401)

Due to the widespread use of concrete structures in different climatic conditions, the issue of damage to these types of structures and as a result of their repair and maintenance, is one of the main topics discussed by concrete experts. One of the causes of corrosion of steel in reinforced concrete in corrosive environments, especially on the shores of the Persian Gulf, is chloride ion. There are many factors affecting the penetration of chlorine ions in concrete, all of which can be summarized in the quality of concrete. One of the main materials used in reinforced concrete structures in corrosive conditions is surface coating. In this study, the performance of five different types of processing in the marine environment (Persian Gulf) was investigated. Have: 27-day treatment with water, 6-day treatment with water, 3-day treatment with water, 1-day treatment with water, treatment with curing agent and without curing. Based on the results, the best performance in terms of resistance to chloride ion penetration varies depending on the exposure conditions. Observations show that curing with curing agent has a good performance in terms of resistance

Water management in rail transport as one of the important and effective parameters plays a major role in increasing the life span of rail structures and subsequently in the economic, industrial and social fields of countries. In this research, it has been tried according to similar experiences from past studies in this field and gathering the opinions of experts in the country, extensive field studies, the use of inspection checklists, statistical information and with the correct understanding of the failures related to water management in concrete bridges and Finally, with the TOPSIS method, according to water engineering standards in bridge maintenance and repairs, it is possible to rank the prefabricated concrete bridges of the General Directorate of Northern Railways of Iran based on water management standards. The results of this research will help employers and managers in charge to be able to properly manage bridges in water engineering, considering the available capital and limited resources.

A large number of river engineering projects, e.g. design of flood-control discharges, realignment of river channels, bank protection and sediment transport, requires accurate estimation of discharge in the compound channels such as rivers. Shiono-Knight method (SKM) is known as a capable tool to modeling discharge in prismatic compound channels. This research used the SKM, which is based on solving two-dimensional equations for flows in open channel by averaging the Navier-Stokes equations. Firstly, the values of depth-averaged velocities and discharge were calculated, then those compared with measurement data in 92-93 time period. Finally, the relation between depth and discharge flow have been stablished for 92-93 time period. The results of predicted depth-averaged velocity and discharge obtained from SKM compared with measured values indicate that SKM can accurately predict the velocity distributions if the two coefficients of friction factor and Roaring manning are chosen based on accurate patterns. The results of model shows to be not good agreement with experimental data. The discharge and depth-averaged velocity were estimated with 3.8 and 12.5 percent error.

  Water discharge is a term in the water industry that refers to the amount of water that passes through a certain point per unit of time. Discharge rate is the amount of water that passes through a specific point such as a river,, water channel, dam valve, pipe or any other structure such as a faucet cartridge in a unit of time. In the metric system, water discharge rate is expressed in terms of cubic meters per second, cubic meters per hour, or liters per second. The unit of cubic meters per second is used for large flows such as rivers and large canals, and the unit of liters per second is used for the flow of water in wells and water that enters leaks. Measuring the discharge of the river has many effects on people's lives. Knowing the amount of water entering the areas of a river's catchment area is very important in agriculture, potential risks to human and animal life, industries, etc. Therefore, predicting river discharge can lead to effective management and prevent serious damage in the mentioned areas. According to the mentioned cases, the purpose of the presented paper is to predict the river discharge using deep learning techniques. In order to do this, the discharge of the Zayandeh Rood River at Qala Shahrokh station has been investigated and predicted using two techniques - ANFIS and LSTM. The simulation results show 93% to 94% accuracy in predicting the discharge of the studied river.

Temperature, Salinity and density are as some of physical properties of sea water often varying there. Thermocline is a property as temperature varying in water column and having variations in terms of time and space. Study and investigation of existence and developing trend with seasonal variations conduct the researcher to some information about inter fluid events. Numerical methods have errors and approximations. Predicted values will be closer to real ones depending on more knowledge about influence of present forces and effective factors on the problem; so little errors happen in numerical study. Of course it is helpful to predict results for different time periods in suitable time and so compete them with measured values for evaluation of the results in the case study zone. In this research running a numerical model during a 6 months period from winter using measured values of temperature (ROPME 1992), and applying initial and boundary conditions, also effective factors on physical conditions variations in the zone, summer temperatures are resulted; Therefore formation and development of thermocline will be studied. In fact, development of thermocline from Strait of Hormuz to northwest of the Persian Gulf (Arvand river estuary) has been investigated by numerical modeling of temperature variations as dominant parameter.

The land subsidence phenomenon has caused serious damage to agricultural lands, residential buildings, roads and etc. due to excessive extraction of underground water, drought and other factors in most plains of Iran, especially in the plains of Chaharmahal & Bakhtiari province. In this article, the main and effective parameters of the subsidence phenomenon are investigated in the Lordegan plain and also the Barm spring of Lordegan City. Site investigation and observation and obtained data from the plain's hydrograph, as well as the damages and problems that occurred on the surface of the plain and around the spring, indicate the occurrence of land subsidence in this region. Underground water level dropping, discharge decreasing in the spring, creation of cracks on the street and buildings and etc. indicate the occurrence of subsidence. At the end, according to the conditions of the region, several solutions have been presented to deal with the phenomenon of subsidence in Lordegan city.