Journal of Materials and Engineering Structures

469-484

Authors: Salmabanu LUHAR, Ismail LUHAR

The present manuscript stands for the review on the topic of durability attribute of concretes developed by means of green conception with incorporation of a variety of solid industrial waste slag from Ground Granulated Blast Furnace, silica fume, rice husk ash, pulverised fly ash, glass powder waste as well as materials that have undergone recycling in order to know its degree of sustainability. It is highly sought-after to transform these types of waste into a precious adding up materials in place of Ordinary Portland Cement (OPC) in building-up of Green concrete with affordable cost and more essential with a little carbon footprint. How far these Green concept concretes have succeeded in context to its durability characteristic is the principal focus of this review study. There prevails an enormous demand for cost-effective construction materials for offering enough residences and infrastructure networks to get rid of the burgeoning population on the planet earth. The centre of attention is to make researcher, engineer and infrastructure related peoples, as well as construction industry au courant of absorbing the, dissipate materials and their promotion as an acceptable, sustainable and cost-effective building materials. The apposite standards of durability and still excellent researches on the sustainability of this novel Green concept concrete will encourage for espousal of gargantuan construction and infrastructures projects globally. Looking to the above facts, it can be predicted that the said Green technology bestows the impression to have dazzling potential and its approval in construction industries which establishes it as the most promising future edifice material.

501-512

Authors: A. Chithambar GANESH, M. MUTHUKANNAN

This research work investigates the effect of utilization of glass fibers in geopolymer concrete made of Manufactured sand (M-sand) over its fresh and hardened properties and understand the influence of fibers over reducing the brittleness of the matrix. Geopolymer concrete synthesized in this study is Fly ash- GGBS blend type with optimum molarity cured under heat condition. Fresh property of the fiber reinforced geopolymer concrete was accessed using compaction factor test. Mechanical properties such as compressive strength, split tensile strength, flexural strength, impact strength, ductility factor, first crack toughness, failure crack toughness and ultimate failure toughness were measured and their results are analyzed and discussed in this work. Later, SEM analysis was carried out over the optimum fiber reinforced geopolymer concrete samples to understand the bonding and the effectiveness of the fiber reinforced geopolymer concrete made of M-sand. Incorporation of glass fiber s proved to be more beneficial and yielded a hybrid concrete with increased strength properties. The performance of fiber s could be measured precisely in increasing the ductility and impact strength. Scanning Electron Microscopy (SEM) analysis showed better bonding between the fiber s and the matrix. This study unleashes an enormous scope for the practical implication of fiber reinforced geopolymer concrete as a building material.

525-534

Authors: Humphrey DANSO, Joseph Kent BOADI

The use of natural sand as fine aggregate in concrete is becoming problematic due to scarcity and pressure on mining of the resource. Alternate sources such as the use of industrial waste as replacement of natural sand in concrete are gaining popularity as a sustainable construction material. The aim of this study is to examine the possibility of using bauxite mining waste as a fine aggregate replacement for concrete production. The quantities of sand replaced with bauxite mining waste used are 0, 25, 50, 75 and 100%. Cube, cylinder and beam specimens were molded and cured for 7, 14, 21 and 28 days, and tested for density, compressive strength, tensile splitting strength and flexural strength. The study found that there was a slight increase in density of bauxite mining waste produced concrete over the control as the quantity of bauxite residue increased. The study further revealed a significant increase in compressive, tensile splitting and flexural strengths of the concrete produced with bauxite residue as compared with the control, with an increase between 60.3 and 65.5%. Additionally, a good correlation was established between the bauxite contents and the density of concrete produced with bauxite mining waste, recording R2 values between 0.9749 and 0.9896. The 100% bauxite residue replacement of sand obtained the highest strength properties in the concrete. The study, therefore, concludes that it is feasible to use bauxite mining waste as a fine aggregate replacement in concrete production. It is recommended that further studies should be conducted on the durability and chemical properties of concrete produced with bauxite mining waste as the current study only focused on the strength properties.

547-563

Authors: Y. DANYUO, T. ZAKARIYYAH, S. NASIRU, K. MUSTAPHA, S. T. AZEKO, S. A. BELLO, M. Abade-ABUGRE, J. YIRIJOR, V. ANYIDOHO, F. McBAGONLURI

The study presents the mechanical properties of polymer-based composites reinforced with chemically modified banana fibers, by alkalization in different concentrations of sodium hydroxide (NaOH). The fiber weight fraction has a great effect on the mechanical properties of the composites. Stiff composites were obtained at 6 wt% fiber fractions with Young’s modulus of 254.00 ±12.70 MPa. Moreover, the yield strength was 35.70 ±1.79 MPa at 6 wt% fiber fractions. However, the ultimate tensile strength (UTS) and toughness of the composites were obtained at 5 wt% fiber fractions. Statistical analyses were used to ascertain the significant different on the mechanical properties of the fibers and composites. The implication of the results is then discussed for potential applications of PDMS-based composites reinforced with chemically modified banana fibers.

583-592

Authors: Balraj SINGH, Parveen SIHAG, Anjul TOMAR, Ankush SEHGAD

High strength concrete (HSC) define as the concrete that meets a unique mixture of performance uniformity requirements that cannot be reached routinely using conventional constituents and regular mixing, placing, and curing events. The modeling of such type of concrete is very difficult. In this investigation, the performance of the random forest regression and M5P model tree were compared to estimate the 28th day compressive strength of the HSC. Total data set consists of 83 data out of which 70 % of the total dataset used to train the model and residual 30 % used to test the models. The accuracy of the models was depending upon the three performance evaluation parameters which are correlation coefficient (R), root mean square error (RMSE) and maximum absolute error (MAE). The results recommend that random forest regression is more accurate to predict the compressive strength as compare to M5P model tree. Sensitivity analysis indicates that water (W) and Silica fumes (SF) are the most valuable constituents of the HSC and compressive strength mainly depends on these constituents.

609-626

Authors: Mohamed KHELLADI, Mohamed ABED, Redha REBHI

The design of a new base isolation system is proposed in this research with the objective that the system does not transmit any force to the structure under horizontal loading. The structure must remain operational and steady. Before investigating the dynamics problem of the base isolation system, the isolator components of the model can be solved analytically using different approaches. In order to calculate the deformation of any element of the isolator due to a compressive vertical load, the analysis focuses on the primary instability region to determine all deformations parameters which can lead to frictions coefficients. This region is located at the interaction contact point between the elements. The design is based on the contact point developed by different approaches. In the present study, the mathematical analysis methods by using formulations can calculate the different dimensions and deformations of the elements of the system and which are verified using ANSYS finite element analysis. After ensuring the adequate dimensions of the different parts of the isolator system from the analysis, the system can be applied on the structure. This technique can reduce significantly the displacements and accelerations at the underground level with a new seismic isolation system, which it is an uncoupled system between the structure and the underground.