Engineering Commons^™

Analysis Of Methods Of Construction And Application Of Modern Anti-Radar Missiles, A S. Solonar, P A. Khmarski, B M. Mukhammedov, G Sh Tuganov

Technical science and innovation

The analysis of methods of construction and application of modern anti-radar missiles (ARM) is carried out. The analysis allowed us to identify the most distinctive features of ARM such as: high flight speed (600-1200 m/s), limited launch range, different flight paths and it is oriented towards the attacked radar, small effective distribution surface (ESR), due to a sharp increase in the weight and size characteristics of the homing head of the homing head outside the frequency range (from 0.5 to 40 GHz), radio electronic means of the ARM are not created, the large range and high speed of tuning the …

Analysis Of Possible Causes Of Industrial Injuries And Accidents At Coal Industry Enterprises, F U. Otabekov, M Z. Naimova

Technical science and innovation

In this article, the issues that a person may face unfortunate events due to a certain reason due to the influence of various dangerous and harmful factors in the course of his life activities are resolved. Depending on the type and degree of exposure or the cause of the accident, the type and degree of injury may also vary. In most cases, injuries and damages occur suddenly and can lead to unexpected and unexpected consequences. Let's imagine that an unfortunate event happened by chance. In this situation, many people lose their senses, start to panic, hurry, become overly nervous or …

Effect Of Hot Weather Concreting On The Mechanical And Durability Properties Of Concrete-A Review, Rawan Ramadan, Hassan Ghanem, Jamal Khatib, Adel Elkordi

BAU Journal - Science and Technology

Nowadays, hot weather is an essential motivator that leads concrete to lose its special characteristics. The high loss of moisture by evaporation and rapid hardening encourage the cracking potential and placement operations. The fresh mixed and hardened concrete tend to be damaged due to several conditions such as: high concrete temperature, High ambient temperature, low relative humidity, and high wind speed. These circumstances accelerate the rate of moisture loss and cement hydration. This article briefly reviews hot weather concreting problems precautions, and curing methods and also discusses the role of incorporation SCMs in reducing the temperature of concrete and enhancing …

Assessing The Influence Of Overweight Axles On Rutting Lives In Flexible Pavements Using Parametric Survival Analysis, Ali Hatoum, Jamal Khatib, Firas Barraj, Adel Elkordi

BAU Journal - Science and Technology

The existence of rutting or permanent deformation on flexible pavement layers has always been a concern that negatively affects the performance of roads by reducing the lifespan of pavement structure and by posing a safety risk for vehicles over the road. Traffic overloading is one of the primary factors that accelerates the deterioration of flexible pavement. This study aims to determine the time to failure of the flexible pavement structures associated with rutting, to indicate the most significant factors affecting rutting, and to assess the influence of overweight axles on pavement rutting life using parametric survival analysis. The data used …

Damage Stability Study Of A 500 Dw Ro-Ro Ferry Vessel, Zulfaidah Ariany, Budhi Santoso, Sarwoko Sarwoko, Nauval Abdurrahman Prasetyo

Makara Journal of Technology

The development of the crossing transportation industry is currently increasing in the island areas. The use of Ro-Ro type ferry boats is extremely efficient in moving people, goods, and vehicles. The current research focuses on the damage stability of the 500 DWT Ro-Ro ferry, which aims to meet the needs of the Ro-Ro ferry in the archipelago area. The previously existing initial design of a barge hull with a main size Lpp = 40.15 m, B = 12 m, H = 3.2 m, and T = 2.15 m was used to analyze the damage stability condition further. First, the drawings …

Solar Chimney Power Plants: A Mini Review, Ahmed Reda, Waseem Salah, Ahmed Suwailem, Shehab Eldin Ahmed, Omar Lasheen, Amira Elkodama, Moustafa R. Shousha, Amr Ismaiel, Anas A. Rahman

Future Engineering Journal

The main investigations of a novel solar thermal application known as SCPP are summarized in this paper. It is a method of producing electricity from solar energy that relies on the fact that air rises when it is heated. An adequate position within a tall chimney can be utilized to position a turbine to turn it, creating an updraft that can be used to generate power. This system's specifications, design, construction, and use are all covered in the paper along with experimental and analytical research related to it. It also emphasizes the development and execution of SCPP programs.

Low-Cost, Low-Weight Test Rig Design For A Laboratory-Scale Twin Rotor Wind Turbine, Ahmed Ayoub, Ahmed Elzeedy, Mahmoud Elkordy, Eslam Ayad, Mohamed Waleed, Amira Elkodama, Amr Ismaiel

Future Engineering Journal

Multi-Rotor Wind Turbine (MRWT) has been proven advantageous over Single-Rotor Wind Turbine (SRWT) in many aspects. In order to study the performance of MRWT over SRWT, this work presents a low-cost and low-weight design for a test rig for laboratory-scale wind turbine configurations. The configurations under study are a single-rotor, and a twin-rotor of the same size with a diameter of 30 cm. Aerodynamic loads have been calculated using the Blade Element Momentum (BEM) method, then the loads were used for stress analysis over the test rig proposed. The test rig is designed on Solidworks and the aerodynamic and inertial …

Performance Comparison Of Several Control Algorithms For Tracking Control Of Pantograph Mechanism, Laylaa Mahmoud Eng, Mohamed Shamseldin Dr, Mohamed Sallam Dr, Abdelghany Mohamed Prof

Future Engineering Journal

A sort of parallel manipulator known as a pantograph robot mechanism was created primarily for industrial requests that required high precision and satisfied speed. While tracking a chosen trajectory profile requires a powerful controller. Because it has four active robot links and one robot passive link in place of just two links like the open chain does, it can carry more loads than the open chain robot mechanism while maintaining accuracy and stability. The calculated model for a closed chain pantograph robot mechanism presented in this paper takes into account the boundary conditions. For the purpose of simulating the dynamics …

Relative Rate Observer Self-Tuning Of Fuzzy Pid Virtual Inertia Control For An Islanded Microgrid, Ahmed H. Mohamed, Helmy M. El Zoghby, Mohiy Bahgat, A. M. Abdel Ghany

Future Engineering Journal

Expanding the usage of renewable energy in islanded microgrids leads to a reduction in its total inertia. Low inertia microgrids have difficulties in voltage and frequency control. That affected saving its stability and preventing a blackout. To improve low inertia islanded microgrids' dynamic response and save their stability, this paper presented relative rate observer self-tuning fuzzy PID (RROSTF-PID) based on virtual inertia control (VIC) for an islanded microgrid with a high renewable energy sources (RESs) contribution. RROSTF-PID based on VIC's success in showing remarkable improvement in the microgrid's dynamic response and enhancement of its stability. Moreover, it handles different contingency …

Dynamic Behaviors Of Micp And Fiber-Treated Calcareous Sand Under Dynamic Triaxial Testing, Rui Wang, Xiao-Hua Pan, Chao-Sheng Tang, Chao L, Dian-Long Wang, Zhi-Hao Dong, Bin Shi

Rock and Soil Mechanics

To improve the liquefaction resistance of calcareous sand foundations, microbially induced calcium carbonate precipitation (MICP) technology and fiber reinforcement technology was combined to treat the calcareous sand sampled from the South China Sea. Based on dynamic triaxial tests, the dynamic behaviors of MICP-treated and fiber-reinforced calcareous sand, including dynamic strain, dynamic pore pressure, stress−strain hysteresis loop and dynamic modulus of elasticity, were analyzed. Then, the strengthening mechanism of MICP and fiber on the mechanical properties of the treated calcareous sand was explored from the microscopic point of view, based on the scanning electron microscope (SEM) test results. The results show …

Experimental Study On Internal Erosion Behaviors Under Fluctuating Hydraulic Condition Using Transparent Soil, Ze-Zhi Deng, En-Yue Ji, Gang Wang

Rock and Soil Mechanics

Internal erosion is a phenomenon that fine particles migrate through the channels within coarse matrix under seepage flow. Previous studies mainly focused on the internal erosion under steady hydraulic gradient, while the studies on the behavior and mesoscopic mechanism of internal erosion under fluctuating hydraulic condition were rarely reported. In this study, a setup of transparent soil seepage test was developed. Seepage tests on two types of soils with different internal stability were conducted under steady and fluctuating hydraulic conditions respectively to investigate the internal erosion behaviors under fluctuating hydraulic condition. The macroscopic experimental phenomenon showed that when the hydraulic …

Modification Of Linear Regression Method For Rock Shear Strength Parameters Under Triaxial Condition, Bin Li, Da-Guo Wang, Zhi-Liang He, Peng Wang

Rock and Soil Mechanics

The triaxial strength envelope of rocks is usually nonlinear, and the shear strength parameters obtained by the linear regression method (LRM) are highly sensitive to confining pressure. In order to enable LRM to consider the influence of confining pressure on the estimation of shear strength parameters, the confining pressure effect coefficient of triaxial strength of rocks is defined. An exponential function is constructed to express the relationship between the coefficient and confining pressure, which is also introduced into the correction of LRM. A linear regression method considering confining pressure effects (CCPE-LRM) is proposed. At the same time, a rationality test …

Experimental Research On Fracture Initiation Pressure Of Conventional Triaxial Slurry Fracturing In Similar Material Of Sandy Mudstone, Hua Cheng, Xiang-Yang Liu, Ru-Kang Cao, Xue-Song Wang

Rock and Soil Mechanics

To further explore the fracture initiation mechanism of fracture grouting in typical sandy mudstone from Huainan and Huaibei mining areas in China, a conventional triaxial fracture grouting test device was developed, and the model test of fracture initiation pressure of slurry fracturing in similar material of sandy mudstone was carried out. Based on the test results, the influences of rock strength and stress state on grouting fracture initiation pressure and fracture propagation pattern were analyzed, and the fracture initiation mechanism of fracture grouting in sandy mudstone was revealed. The results show that there is a positive correlation between the initiation …

Soil-Water Characteristic Of Biochar-Clay Mixture In The Full Suction Range, Ming-Yu Li, Wen-Jing Sun, Qiang Huang, De-An Sun

Rock and Soil Mechanics

Soil-water characteristic curve (SWCC) plays an important role in defining the hydro-mechanical behavior of unsaturated soils. Biochar has the properties of porous structure, high specific surface area and high adsorption. The hydraulic characteristics of biochar-amended soil may change due to the influence of natural environmental factors when applied as the cover layer of landfills. In order to study the effect of biochar content on the water retention behavior of biochar-clay mixture in full suction range, the suction of samples was controlled by vapor equilibrium technique (suction range 3–368 MPa), filter paper method (suction range 0–40 MPa) and pressure plate method …

Macro-Mesoscopic Investigation Of Cushioning Mechanism Of Recycled Concrete Aggregate Under Successive Rockfall Impacts, Yu-Chen Su, Yuan Wang, Hui-Ming Tang, Heng Zhong, Xin Li, Chao-Fu Liu, Ya-Ru L

Rock and Soil Mechanics

Cushion materials can effectively reduce the impact load acting on the rigid protective structures such as shed tunnel and improve the impact resistance of the structures. In order to investigate the variation of cushioning performance of recycled concrete aggregate (RCA) under successive impacts, drop weight impact tests and discrete element simulations are carried out. Test results show that compared with the quartz sand cushion, the transmitted load at the center of concrete shed for RCA under the first impact reduces by 83%, and it is distributed more uniformly. With the increase in the number of impacts, the cushioning performances of …

Three-Dimensional Stability Limit Analysis Of Cracked Loess Slopes, Xue-Liang Zhu, Sheng-Jun Shao, Xiao-Jun Shen, Shuai Shao, Xiao-Kang Liu

Rock and Soil Mechanics

The development of vertical cracks in loess slopes often affects slope stability. Compared with the plane strain mechanism, the slope stability analysis under the three-dimensional (3D) failure mechanism is closer to the actual slope instability. Based on the upper bound method of plastic limit analysis, different failure mechanisms (face failure, toe failure and base failure) of 3D loess slope with pre-existing cracks are considered, the energy balance equation and its dimensionless critical height expression γH/c are established, and the upper bound solution of critical height is obtained by random search method. The effects of constraint width, slope angle, internal friction …

Statistical And Regression Analyses Of Sands Stiffness In Triaxial Tests And Application Of The Results, Sharafutdinov Rafael

Rock and Soil Mechanics

The density and stress state significantly impact on the sand stiffness. Many of hardening soil models used for geotechnical computation are based on Duncan-Chang model and do not consider the influence of density on the soil stiffness. In course of triaxial compression of very dense or loose sands, the shear strains rise induces significant changes in density. In order to evaluate the effects of grain size distribution, density, and stress state on stiffness, the results of 962 isotropic triaxial tests on soil samples from 15 Moscow and Minsk construction sites were processed using statistical and regression analysis. As a result, …

Influence Of Particle Size Distribution And Initial Dry Density On The Characteristics Of Subgrade Mud Pumping, Yu Ding, Yu Jia, Xuan Wang, Jia-Sheng Zhang, Xiao-Bin Chen, Hao Luo, Yu Zhang

Rock and Soil Mechanics

The subgrade mud pumping of heavy-haul railway is widespread and harmful, which seriously affects the stability of tracks and the safety of train operation. The properties of railway subgrade soil, such as the particle gradation, the void ratio, have a significant impact on the characteristics of subgrade mud pumping under train load. In this study, a series of remolded samples consisting of silty clay and different content of Kaolin was subjected to mud pumping tests with a self-developed test model. The influence of varying particle gradations (Kaolin content) and initial dry densities (void ratio) on axial strain, excess pore water …

Home With Hope: Green Infrastructure Eee 495: Urban Water Projects, Madeline Mcintosh, Victoria Chillscyzn

Purdue Journal of Service-Learning and International Engagement

Urban landscapes have serious impacts on water quality through the disruption of the hydrologic cycle. The Purdue University course, Environmental and Ecological Engineering 49500: Urban Water Projects, seeks to use student-led service-learning projects to improve both water quality and quantity in the Wabash River water-shed. This year, students investigated and implemented strategies to guarantee that previous implementations succeed well into the future. Two students, Victoria Chillscyzn and Madeline McIntosh, were part of a team

working with the local nonprofit Home with Hope. Through interviews, a survey, and site visits, the team determined action items to improve the form and function …

Building Services Engineering November/December 2022

Building Services Engineering

No abstract provided.

Experimental Study On Influence Of Positional Relationship Between Dynamic Load And Long Axis On Impact Rockburst In An Elliptical Cavern, Yang Wang, Dong-Qiao Liu, Fu-Qiang Ren, Tian-Xiang Hu, Man-Chao He

Rock and Soil Mechanics

In order to explore the influence of the relative positional relationship between the dynamic load and the long axis of the elliptical cavern on the characteristics of impact rockburst, a cuboid sample with an elliptical hole is prepared. With two positional relationships of disturbance direction parallel or perpendicular to the long axis of the elliptical cavern, the elliptical cavern impact rockburst experiments are carried out. With the aid of video recording device, the characteristics of the impact rockburst of the elliptical cavern are discussed in terms of damage process of rockburst ejection, ejection speed, failure mode and fragment size. The …

Deterioration-Buckling Failure Mechanism Of Consequent Bedding Limestone Bank Slope In Three Gorges Reservoir Area, Guo-Qiang Yan, Yue-Ping Yin, Bo-Lin Huang, Lei Hu

Rock and Soil Mechanics

In the Wuxia section of the Three Gorges Reservoir area, it is found that there are many deformation signs of sliding-bending along the bedding bank slope, and the cyclic fluctuation of reservoir water worsens the deterioration and instability of the bank leading edge. Taking Qingshi #6 slope in the Wuxia section as an example, an laboratory generalized model is constructed to study the catastrophe mechanism of bedding limestone bank slope under the deterioration of rock mass in hydro-fluctuation belt. The research shows that: the bank slope is in a stable state as a whole for a long time before impoundment. …

Investigation Of The Influence Of Interaction Of Wraparound Geogrid-Sand On The Load Bearing-Settlement Behavior Of Strip Footings, Hussein Ahmad, Ahmad Mahboubi, Ali Noorzad, Mohammad Hosein Hoseini

Rock and Soil Mechanics

The use of high-quality materials and the strengthening of soil layers, especially in areas with poor bedding, are among the most important factors in stabilizing and achieving the useful life of building structure. An experimental study on a strip footing coated with unreinforced, geogrid-reinforced, and folded geogrid layers of fine sand is presented in this paper. Testing procedures evaluate variables such as the number of planar geogrid layers, the position of the folded geogrid within the soil, the thickness of the geogrid folded layer, the overlap lengths of a folded geogrid, the spacing within folded layers of geogrid, and several …

Study Of Multi-Parameter Dominant Grouping Method Of Rock Mass Discontinuity Based On The Principal Component Analysis, Fu-Rui Dong, Shu-Hong Wang, Qin-Kuan Hou

Rock and Soil Mechanics

Statistical analysis and clustering of discontinuities existing in rock mass are the basis of rock mass engineering stability analysis. Considering that the mechanical and hydraulic properties of discontinuities are affected by many factors such as occurrence, trace length, aperture, roughness, and filling state, a multi-parameter dominant grouping method of rock mass discontinuities based on principal component analysis is proposed. Firstly, the principal component analysis method is used to select the criterion of the dominant grouping and calculate the weight value of its participation in similarity measurement. Secondly, the global optimal initial clustering center of the fuzzy C-means clustering algorithm is …

Mechanical Properties Of Slag-Fly Ash Based Geopolymer Stabilized Sandy Soil, Jin-Jin Zhang, Bo Li, Chuang Yu, Mao-Yu Zhang

Rock and Soil Mechanics

Silicate cement as a conventional soil curing agent has problems of high energy consumption and high emissions, and researchers have been seeking a more economical and environmentally friendly alternative to cement. In this study, geopolymers based on ground granulated blast-furnace slag (GGBS) and fly ash (FA) were used to reinforce sandy soils, and the effects of different factors on the mechanical properties of geopolymer stabilized sandy soils were investigated by adjusting the type and ratio of exciter, slag-fly ash ratio, water-cement ratio, and curing conditions. The specimens were studied in depth by unconfined compressive strength (UCS) test, electron computed tomography …

Experimental Study Of Fracture Dynamic Evolution Process Of Grouted Specimen Under Uniaxial Compression Based On Ct Scanning, Chang-Xing Zhu, Jia-Xin Sun, Yan-Wei Wang

Rock and Soil Mechanics

To study the fracture dynamic evolution process of grouted specimens under loading conditions, the graded gravel grouted specimen was periodically scanned during the uniaxial compression damage process using a CT scanning system. Based on the image reconstruction technique, the spatial visualization of the fracture structure inside the test grouted specimen block is achieved, and the structural characteristic parameters are characterized quantitatively such as the number and volume of fractures. The gray value and fractal dimension of the CT slices are calculated using Python programming to analyze the mesoscale damage extent at different loading stages of the grouted specimen. It is …

Application Of Nonlinear Soil Resistance-Pile Lateral Displacement Curve Based On Pasternak Foundation Model In Foundation Pit Retaining Piles, Yan-Peng Zhu, Lin-Ping Wu, Duo-Bang Shi, Zhuang-Fu Zhao, Xiang-Xiang L, Xin-Guo Duan

Rock and Soil Mechanics

As a direct retaining structure in the process of foundation pit excavation, the internal force and deformation of pile under horizontal load have great influence on the safety and economy of foundation pit engineering. In order to calculate the internal force and deformation of the supporting pile more accurately, the nonlinear foundation reaction modulus is obtained according to the nonlinear soil resistance-pile lateral displacement (p−y) curve of pile-soil interaction. At the same time, the Pasternak two-parameter foundation model is introduced to fully consider the continuity of pile side soil deformation. The differential equation of retaining pile deflection considering pile-anchor deformation …

Forecasting The Demand For Asphalt Concrete In Karbala Governorate, Ghayath Ali, Sawsan R Mohammad, Shakir Al-Busaltan

Al-Bahir Journal for Engineering and Pure Sciences

The challenge of forecasting asphalt concrete demand in the Karbala governorate is the subject of this study. Population and number of vehicles in Karbala are considered among the independent (explanatory) variables taken into consideration. These explanatory variables ' historical data have been gathered and examined. The historical data of each explanatory variable has been linked to the historical demand for asphalt concrete in the governorate using regression techniques in the Statistical Package for the Social Sciences (SPSS) program version 26.

A model to forecast the governorate's demand for asphalt concrete has been developed based on these factors. The forecasts have …

Features Designing Special Clothing For The Hot Climate Of Uzbekistan, N Kh Mirtalipova, N A. Isaxujayeva

Technical science and innovation

This paper considers the issues of establishing the relationship between the properties of fabric, clothing design and the comfort of clothing; communication of the size of the human body, allowance for free fitting, modern design when developing the design of clothing; connection of the allowance for free fitting with a suitable air gap. A diagram is given that characterizes the dependence of the comfort of clothing on its design and properties of fabrics. A mathematical model of the processes of air exchange in the underwear space is considered, which will allow obtaining more complete information and establishing more stringent dependences …

Inversion Iterative Correction Method For Estimating Shear Strength Of Rock And Soil Mass In Slope Engineering, Wei Jiang, Ye Ouyang, Jin-Zhou Yan, Zhi-Jian Wang, Li-Peng Liu

Rock and Soil Mechanics

For the slopes that have failed or deformed significantly, the shear strength of rock and soil mass is frequently inversely estimated based on a factor of safety assumed. For the slope with a sliding surface passing through multi-layer rock and soil mass, it is unreasonable to achieve this goal by blind trial. To solve this issue, back propagation (BP) neural network is constructed using shear strength of multi-layer rock and soil mass as the input, and the factor of safety of slope, the entrance and exit positions of the sliding surface obtained by Geoslope as the outputs. Then, based on …