KUFA JOURNAL OF ENGINEERING

It is a significant issue to analyze and understand the pile’s behavior as well as to predict the piles’ capacity exposed to uplifting load when designing a foundation. Experimental model tests have been conducted for a single pile embedded in cohesionless soil and subjected to uplift force. The experimental tests were performed using open-ended steel pipe piles with circular cross-sectional area an outer diameter of 50 mm in steel soil box (0.5*0.5) with four different height (0.30, 0.50 and two with 0.40 m). The tested piles have been embedment with penetration ratios (PR=L/D) of 10. Three different densities (25%, 50% and 75%) have been used to perform the tests. In addition three tests have been made with relative density of 50% to investigate the function the developed soil column inside the pile (soil plug) during installation. The results revealed that the behavior of single piles depends mainly on soil density and the ultimate pull-out capacity of the pile increases with the increasing of the soil relative density and used the data from this tests to presented formula to estimate the IFR and takes the soil state parameter as a qualitative variable. The results showed also that the removing of plugging soil decreases the pile’s pull-out capacity by about 85%. Whilst, using of closed-end or filled with concrete give higher capacity than that of open-end pipe pile by about 33% and 87% respectively.

The present research paper deals with the finite element modelling of continuous one-way reinforced concrete (RC) slabs strengthened by near surface mounted (NSM) bars under static loads. Seven specimens that consisted of one reference slab without strengthening and six strengthened slabs were used, with 2400 mm total length, 500 mm width and 100 mm thickness. The average compressive concrete strength at 28 days’ age was about 31MPa was used. Slabs were simulated with finite element computer program. The results of the control and strengthened slabs were compared with the experimental results. It is observed that the results of the strengthened slabs are in close agreement with the experimental results with a maximum difference in the ultimate load of about 6.64%.

Development of self-curing geopolymers is a key consideration among the researchers. One of the challenges that face geopolymers to field application is applying of heat to enhance its mechanical properties. This study focuses on using self-cured, NaOH activated, quartz stone powder by using different cement dosages in producing geopolymer mortar. For this purpose twelve mixes were prepared. The base material, quartz stone powder, was replaced by Ordinary Portland Cement (OPC) in dosages of (0%, 5%, 10%, and 15%) by weight and different sodium hydroxide concentration variations were used. Compressive strength, water absorption and sorptivity were investigated. The results showed that 15% of OPC replacement has optimum influence on some properties of geopolymer mortar. At the same time Sodium hydroxide concentration of 14M achieves the optimum properties. The results revealed that incorporation of OPC and utilization of different NaOH concentrations significantly affected the compressive strength and absorption properties of the mortar.

Reinforced soil technology is considered one of the most important methods of soil improvement due to its simplicity and speed in implementation and saving cost. In this research a strip footing and geogrid (Tensar SS2) were used to reinforced sandy soil and investigated the effect of relative density on bearing pressure and compressibility. The soil was strengthen with four layers of (geogrid Tensar SS2) and used a five relative densities were (30.7%, 49.7%, 56.5%, 64%, and 75.9%) to include cases of loose, medium and dense sand. The results also showed the effect of relative density on the bearing capacity and the settlement as experimental tests indicated that increasing the relative density from 30.9% to 64% gave an improvement in soil bearing capacity, as well as an effective improvement in carrying capacity when increasing the relative density from 64%. The results showed that the bearing capacity when using relative densities of 49.7%, 56.5%, 64%, 75.9% increased by 1.218, 1.287, 1.512, and 2.1799, respectively, of the bearing capacity of reinforced soils with relative density of 30.7%. As for the effect of relative density on the settlement, it was found that the settlement is generally less in the case of soil with higher relative density.

Studies have been carried out on bovine bone due to its abundance and large quantity of hydroxyapatite (HAP) in it while caprine bone has been understudied. In this study, locally sourced bovine and caprine bones were washed in distilled water, defatted at 120°C for 1.5 hr in a pressure pot, ball-milled, sieved to 150 µm particle size and characterised. The X-ray fluorescence (XRF) and Energy dispersive X-Ray Spectroscopy (EDS) analysis revealed calcium, phosphorus and carbon as the main components. Both bones contained carbon and oxygen due to the presence of organic collagen but the quantity in caprine bone was a bit higher as revealed by the Fourier Transform Infrared Spectroscopy (FTIR) and EDS spectra. A slight difference in thermal decomposition patterns was recorded while X-Ray diffraction analysis (XRD) revealed the presence of identical functional phases. The microstructures showed needle-like and pebble-like shapes for bovine and caprine respectively, also on visual examination of the Scanning Electron Micrograph (SEM), the bovine samples tended to have particle surface roughness more than caprine. Consequently, the chemical properties of both bone raw samples were insignificantly different from each other except for collagen composition and morphology.

In this study investigates the design of a solar-powered groundwater pumping system to irrigate desert lands in Najaf, Iraq. The water pumping rate was calculated for the land to be cultivated, which is 83.4 m³ / day. We designed an irrigation system for the three agricultural crops that depend on soil and water sensors in their work. Where a land area of 12500 m² was fed with water through two well pumps pumps (5.5 KW) and a tank (0.78 KW), the number of panels required to operate the irrigation system was 27 monocrystalline solar panels of N type 390 W. Matlab/Simulink and the theoretical results showed that the system can irrigate these lands, thus reducing the waste of electrical energy for the panels, and the purity of the water and air which gives us a green and beautiful space.