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Progress in construction and buildings industry depends on so many parameters especially materials used. Concrete materials are cheap but still need minimization in their costs. Steel is one of the materials used in concrete structural members to support the concrete as reinforcement. In this study a polypropylene rope (PP ropes) were used to support the task of steel reinforcement especially in tension zones and to decrease the total cost of the concrete section. To know how this matter achieved seven concrete beams were casted one of them was without polypropylene ropes as control beam where as others were reinforced only with polypropylene ropes. The dimensions of the concrete beams were (200cm ×30cm ×20cm). Whole concrete tests were done to find out the most effective properties of concrete like compression, rupture modulus and tensile strength. Seven beams were exposed to monotonic load to find out the load at failure and corresponding deflection at mid span. Results show that if four ropes were used in tension zone of the concrete section the strength increased by about 9%. This ratio seems to be low but the cheap cost of these ropes encourages designers to use a greater number of ropes in concrete section. This idea needs more future

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In this paper, silica fume and fly ash class F was used as a supplementary cementing material in cement mortars to evaluate several mechanical properties of SIFCON (Slurry Infiltrated Fibrous concrete) in the way of flexural, compressive and splitting strength which were determined using the standard test method, the impact load resistance was determined using a fabricated instrument described in body paper. plate specimens with dimension of 450mm×100mm×40mm were cast with micro steel fiber of 6% volume fraction were tested under impact load for assessment with references plates at 90 days of age. From the results of the outcome it was found that the performance of conventional mortar is much less than SIFCON specimens. The compressive, splitting, flexural strength and impact resistance for conventional mortar and SIFCON specimens were investigated, a significant development in impact resistance for SIFCON mix at first crack and failure, also the energy demand for the whole failure was which is increased by 9.97 times compared with the conventional mortar. Thus, this present paper displays that SIFCON can be utilized as a powerful option in different development purposes or where the concrete or natural steel fiber reinforce concrete can't execute surprisingly/needed or in situations where such greater strength is imperative and essential.

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Expansive soils are the an un constant volume soil, because, they distend or swell when wetting & shrink when they are dried, therefore they affect the stability of the structures that are rested on it, such as light weight buildings & pavements and, then, damages appear because of the developments of heave and swelling which depend, mainly, on the clay content (less than 0.002mm particles size) which the soil has. The problem discussed her on an expansive soil area at the Iraqi west desert that the new [Wild Hajj] road passes over it, named AL-Bussita area. Stability tests such as maximum dry density, CBR, unconfined and triaxial shear test besides other tests such as swelling tests, (one dimensional oedometer tests), were performed on soil shales taken from this area. The study was continued with a sample from a same soil mixed with the fuel oil. The simulation and experimental results demonstrate that the (8% by weight) was the optimum percent of the fuel oil to minimize the swelling potential, and to get a good engineering soil property and the mixed soil became acceptable to use in earth works of roads.

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ABSTRACT We have proposed a new textile reinforcement which was made from non-corrosive material (smart material: such as steel and glass). That will be effectively reduce the required concrete material, this technique which is called the Textile Reinforced Concrete (TRC). This paper presents a plate specimen with dimension of (500x500x400 mm), to demonstrate the effectiveness of our material we have tested under an impact load during 28 to 90 days with two different conditions simply support and fixed, respectively. Cement mortar with 60 MPa, 7 cm cube shape compressive strength for 28 days has been designed for the casting process of the plate. The reference plate (has 22 sub plates) which is divided into four categories were casted essentially with 3D glass fabric, all these groups have three different thickness (6,10, and 15 mm) indeed a 0.75 volume fraction of the micro steel and ferrocement that is known as mesh chicken wire layers. The simulation and the experimental results demonstrate that, the steel fibre gave higher quality results than the 3D glass fabric and mesh chicken wire, indeed we have proven that the 3D glass fabric with 6 mm gave higher number of blows than the other thicknesses.

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Abstract: Concrete is the most widely used building material, but it is also a recognized pollutant, causing significant issues for sustainability in terms of resource depletion, energy use, and greenhouse gas emissions. As a result, efforts should be concentrated on reducing concrete’s environmental consequences in order to increase its long-term viability. In order to design environmentally friendly concrete mixtures, this research intended to create a prediction model for the compressive strength of those mixtures. The concrete mixtures that were used in this study to build our proposed prediction model are concrete mixtures that contain both recycled aggregate concrete (RAC) and ground granulated blast-furnace slag (GGBFS). A white-box machine learning model known as multivariate polynomial regression (MPR) was developed to predict the compressive strength of eco-friendly concrete. The model was compared with the other two machine learning models, where one is also a white-box machine learning model, namely linear regression (LR), and the other is the black-box machine learning model, which is a support vector machine (SVM). The newly suggested model shows robust estimation capabilities and outperforms the other two models in terms of R (coefficient of determination) and RMSE (root mean absolute error) measurements. 2

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The current study concentrated on the groundwater chemistry in part of Najaf city area to evaluate the groundwater quality for knowing its relevance for agricultural purposes. The quality of groundwater significantly affected by Urbanization and agriculture activities. The (10) samples of groundwater were randomly raised from various wells Najaf farms region by pumps, then resolved for main anions. Anions dominant were Na, Ca and Mg, thence get a criterion index of water quality the ratio of sodium adsorption (SAR) in addition to test electrical conductivity (E.C.). Then, examine those samples of groundwater where used as an irrigation water supplied to several types from of Oryza satival seeds (Yassmin class, Dijla class, Amber 33 class, Alforat class, Amber Baraka class, Mashkhab class) to test germination of seeds. The results of germination of seeds with those samples of irrigation water was between (40%- 100%).

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The use of textile reinforcement made from non-corrosive materials, such as carbon and glass can reduce the required concrete material; this is known as Textile Reinforced Concrete (TRC). This study deals with plate specimens having dimension of 500×500×40mm tested under impact load at 28 and 90 days age under two conditions of ends, simply supported and fixed. Cement mortar with about 60 MPa, 7cm cube compressive strength at 28 days was designed for casting the plates. Plate specimens were divided into four groups, they consist of reference plates (no reinforcement) and plates reinforced with 3D glass fabric having three different thicknesses 6, 10 and 15mm. The results indicate that using 3D textile glass fabric cause an increase in number of blows, reduce in final stage deflection, an improvement in toughness and energy absorption under impact loads. Using 3D textile glass fiber with 10mm thickness gave higher number of blows for 28 and 90 days as compared with 6 and 15 mm. Plates with slice 6mm 3D textile glass fiber in two way reinforced has significantly enhancement in number of blows, the improvement was about (80 - 125%) and (128.5- 114. 3%) for 28 and 90 days respectively. The specimens showed increase in the energy absorption, besides the number and width of cracks was reduced and only few cracks are propagated up to the edge of the plates.

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Abstract: Reinforced concrete (RC) flat slabs are widely employed in modern construction, and accurately predicting their load-carrying capacity is crucial for ensuring safety and reliability. Existing design methods and empirical equations still exhibit discrepancies in determining the ultimate load capacity of flat slabs. This study aims to develop a robust machine learning model, specifically the M5P model tree, for predicting the punching shear capacity of a RC flat slab without shear reinforcement. A comprehensive dataset of 482 experimentally tested flat slabs without shear reinforcement was gathered through an extensive literature review and utilized for the development of the M5P model. The model takes into account influential parameters, such as slab thickness, longitudinal reinforcement ratios, and concrete strength. The performance of the proposed M5P model was compared with existing design codes and other empirical models. The comparison highlights that the developed M5P model tree provides a more accurate and reliable prediction of the punching shear capacity of RC flat slabs. This study contributes to the advancement of structural engineering knowledge and has the potential to improve the design and safety assessment of concrete flat slab structures.

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Abstract: The cement industry is one of the most polluting industries globally, due to the high amount of CO2 emissions generated during production. Improving the sustainability of cement production is thus vital. Waste paper is also a big problem for many societies, especially in developed countries, where the use of board and paper increases almost every day. This work examines the possibility of using incinerated waste paper ash (IWPA) and non-incinerated waste paper (NIWP) as a partial replacement for cement (by weight) in mortar mixtures. For non-incinerated waste paper, the tested replacement levels were 1%, 1.5%, 2.5% and 3.5%, while for incinerated waste paper, the replacement levels were 2.5%, 5%, 7.5%, and 10%. An additional mix without any replacement was also cast for comparison purposes. The fresh and hardened properties of mortar were assessed using flow rate, compressive strength, direct tensile strength, water absorption, and dry density tests, and two test ages (7 and 28 days) were considered for the compressive and tensile strength tests, though water absorption and density tests were undertaken at 28 days only. The results showed that the presence of waste paper (incinerated or non-incinerated) reduced the flow rate of fresh mortar as compared with the reference mix. It was also found that, for the NIWP mixtures, 1% replacement of cement was the most efficient percentage; this increased the compressive strength by 16% and the direct tensile strength by 19% at 28 days of age. For the IWPA mixes, the results showed that the best replacement ratio was 5%, where the compressive strength and direct tensile strength were improved by 10% and 11% at 28 days, respectively. These 1% NIWP and 5% IWPA mixtures gave similar water absorption of 7% to the reference mix.

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Abstract: For the design or assessment of concrete structures that incorporate steel fiber in their elements, the accurate prediction of the shear strength of steel fiber reinforced concrete (SFRC) beams is critical. Unfortunately, traditional empirical methods are based on a small and limited dataset, and their abilities to accurately estimate the shear strength of SFRC beams are arguable. This drawback can be reduced by developing an accurate machine learning based model. The problem with using a high accuracy machine learning (ML) model is its interpretation since it works as a black-box model that is highly sophisticated for humans to comprehend directly. For this reason, Shapley additive explanations (SHAP), one of the methods used to open a black-box machine learning model, is combined with highly accurate machine learning techniques to build an explainable ML model to predict the shear strength of SFRC slender beams. For this, a database of 330 beams with varying design attributes and geometries was developed. The new gradient boosting regression tree (GBRT) machine learning model was compared statistically to experimental data and current shear design models to evaluate its performance. The proposed GBRT model gives predictions that are very similar to the experimentally observed shear strength and has a better and unbiased predictive performance in comparison to other existing developed models. The SHAP approach shows that the beam width and effective depth are the most important factors, followed by the concrete strength and the longitudinal reinforcement ratio. In addition, the outputs are also affected by the steel fiber factor and the shear-span to effective depth ratio. The fiber tensile strength and the aggregate size have the lowest effect, with only about 1% on average to change the predicted value of the shear strength. By building an accurate ML model and by opening its black-box, future researchers can focus on some attributes rather than others.

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Abstract. The idea of the research revolves around the use of by-products of industries (cement kiln dust, fly ash) and their consumption in production of a binder using in manufacture of sustainable concrete with good specifications that exceed the specifications of Portland cement concrete. On the other hand, reducing the manpower, using equipment and tools in casting or compacting of concrete is another factor of sustainability. In this paper, the possibility of using cement kiln dust (CKD) as a percentage of fly ash in the production of alkali activated self-compacting concrete (AASCC) and its effect on the fresh properties, compressive and splitting tensile strength of the resulting concrete was studied., It was observed that the replacement ratios of cement kiln dust CKD instead of fly ash did not affect the workability properties for resulting concrete, where the proportion of (10%) of CKD replacement caused increase in compressive and tensile strengths about 5%, while, (20, 30)% caused decrease in the compressive and splitting tensile strengths about (30, 44)% respectively.