Engineering Characterization of Local Limestone and Marlstone Aggregates in Koya Area as a Case Study

There are huge limestones and marlstone outcrops surrounding the Haibat-Sultan Mountain in the Koya area. Knowledge of the physical, mechanical, and chemical properties of aggregates is important when using them in the construction industry. In this study, the usability of limestone and marlstone as sources of aggregate for construction purposes and different engineering applications was investigated. Results were carried out on the rocks limestone and marlstone from Fatha Formation in the Koya area as a case study. The engineering characteristics that have been mentioned in this study include uniaxial compressive strength (UCS), Los Angeles abrasion value (LAAV), aggregate impact value (AIV), aggregate crushing value (ACV), dry density, porosity, water absorption, and moisture content. The simple non-linear regression analysis has defined mutual relations between laboratory tests. The aggregate degradation properties of the aggregates showed strong correlations with the uniaxial compressive strength of limestone. The results indicated that it is possible to use this type of crushed limestone in concrete and road construction as a base course, while the marlstone aggregates are suitable for subbase courses in road constriction and non-structural concrete application

Comparison between Analytical Equation and Numerical Methods for Determining Shear Stress in a Cantilever Beam

A three meter-length cantilever beam loaded with a concentrated load at its free end is studied to determine shear stresses. In the present study, three cross sections are considered: rectangle (R); I, and T. The study presents a comparison of maximum shear stresses obtained by means of two methods: classical analytical equation derived by Collingnon, and finite element method (FEM) software. Software programs ANSYS and SAP2000 were used. The results show difference between the maximum shear stresses obtained by the analytical equation and the software, being the last is always higher. The average differences for ANSYS and SAP2000, independently of the cross section, were 12.76% and 11.96%, respectively. Considering these differences, correction factors were proposed to the classical analytical formula for each cross section case to obtain more realistic results. After the correction, the average differences decrease to 1.48% and 4.86%, regardless of the cross section shape

Analysis of Flow Around Several Buildings on the University of New Haven Main Campus

The modeling of the wind flow around several buildings on the University of New Haven UNH campus was studied; an understanding of the flow field and the interactions that occur in the airflow between the various buildings is needed to establish optimal placement of a small-scale wind turbine. Identifying a proper location for a wind turbine will ensure maximum power output. The power output is determined by the velocity of the air that passes through the turbine and is proportional to the air flow velocity cubed. The presence of buildings and various structures as well as the flow through and around the buildings impacts the flow field and flow velocity. Modeling of these buildings was done by computational simulation (CFD) with simplified geometries. Buildings dimensions were obtained from the UNH facilities’ department while simplifications were made for modeling using the ANSYS® software suite. The velocity and pressure fluctuations of the air passing around the buildings were computationally acquired for different wind directions. The study considered steady state simulations. Turbulence was modeled using the k-omega and SST equations. Four factors were investigated in this study: influence of wind directions, influence of wind speed, influence of neighboring buildings and influence of turbulence models. The mesh was studied so that the results were independent of the mesh resolution and included examining the dependence of first thickness of the boundary layer y+. The results of the simulations were focused on Buckman Hall and demonstrate that the wind velocity at 5-10 m above the building roof is enhanced numerously, as much as 1.5-2 times the nominal 3-10 m/s inlet velocity. Additional studies are needed to strengthen the results yielded by the model; recommendations are made for future work

Understanding the Use of Timber in Semi-Arid Regions: Kurdistan Region of Iraq, a Case Study

The use of timber in the building industry has expanded in many countries over the last 20 years due mainly to its light weight, low adverse impact to the environment, and fair mechanical properties. Despite the development of the construction industry in the Kurdistan Region in Iraq (KRI) in recent years, timber product utilization is still very limited. Therefore, the purpose of this study was to investigate the feasibility of further utilizing timber-based products in the building industry in semi-arid regions using the KRI as a case study. A review of timber product utilization in the region was conducted first and the general properties of timber products were followed. Based on this, a survey focusing on the current situation and suitability of localized grown timber products was carried out to study the feasibility. This article concludes that the use of timber-based products in the KRI presents different barriers, with the availability in the market and technicality of construction with the material being the strongest ones. The article recommends that it is imperative to further research how to promote timber’s utilization in the KRI to be in line with sustainable development

The Effect of Number of Storey's and Columns Dimensions on the Accuracy of Tributary Area Method

In recent years, the utilization of computer techniques in engineering application has become an irreversible trend. This is achieved through using computer as the device for modeling, analysis, and design. The study mainly has focused on the accuracy of the tributary area method for estimation load , as compared to finite element method by SAP2000, considering the effect of building overall height (i.e. number of storey's) from 1 to 10 and column dimensions (i.e. stiffness) from 20×20 cm to 70×70 cm. According to the analysis of the data obtained, we can see the error in the load computed by the tributary area approximation becomes relatively larger as the number of storey's increases, especially for the lateral load calculations, and the stiffness of the columns increases, the predictions using the tributary area method improves for both axial and lateral forces in the columns

The Possibility of Utilization of Tamper-evident Bands (TEB) as Fibers in Concrete Blends

The impact of tamper-evident bands (TEB) as fiber on the distinctive properties of concrete was examined through a few laboratory tests. In this study, the tamper-evident band (TEB) is the plastic ring left around the neck of bottled drinking water. The properties examined incorporate workability, compressive strength, flexural strength, and splitting tensile strength at 7 and 28 days of moist curing. Three varied fiber volumes were added to concrete mixes at 0.5%, 1.0%, and 1.5% by volume of concrete. The test results show that the employment of 1% (TEB) fibers by volume of concrete lead to the increment of flexural and splitting tensile strengths of concrete 34.5% and 38.56% respectively in comparison to the reference concrete at 28 days of moist curing.nbsp; It can be inferred, according to a preliminary analysis, that tamper-evident bands (TEB) are modern forms of fibers that have a good effect on the improvement of concrete's tensile properties