Spectroscopic investigations, DFT computations and other molecular properties of 2,4-dimethylbenzoic acid

The molecular vibrations of 2,4-dimethylbenzoicacid (DMBA) have been investigated by recording Fourier transform infrared (FTIR) and FT-Raman spectroscopy. The complete vibrational assignment and analysis of the fundamental modes of the compound have been carried out using the experimental data and quantum chemical studies from DFT calculations employing MPW1PW91 and B3LYP methods employing 6-311++G(d,p) basis set. The 1H and 13C NMR chemical shifts have been calculated with the GIAO method using the optimized parameters obtained from B3LYP/6-311+G(d,p) method. Important thermodynamic properties and electronic properties have been calculated. Low value of HOMO-LUMO energy gap suggests the possibility of intramolecular charge transfer in the molecule. Furthermore, the first hyperpolarizability and total dipole moment of the molecule have been calculated

Evaluating the use of lemon grass roots for the reinforcement of a landslideaffected soil from Nilgris district, Tamil Nadu, India

For many centuries, man has been concerned with stabilizing soils in order to either prevent them from being easily eroded or to make them better suited for construction such as for earth building and road construction purposes. Attempts have been made to utilize many natural, synthetic or waste materials for such soil stabilization. Plants have been used as soil cover to prevent erosion and protect slopes. However, there is need to evaluate the engineering characteristics of soils reinforced with plant roots. Consequently, this research work was aimed at investigating the effects of the reinforcement of a landslide-affected soil using the roots of a locally-available plant on the strength and permeability properties of the soil. The natural moisture content, specific gravity, particle size distribution, Atterberg limits, compaction characteristics, shear strength, unconfined compressive strength (UCS) and permeability of the natural (landslide-affected) soil were determined. Results obtained for the natural landslide-affected soil were compared with those of the soil sample admixed with varying proportions (1%, 2%, 3% and 4%) of lemon grass roots. The result shows that the shear strength and UCS of the soil having 4% lemon grass roots is almost double that of the natural soil. Also, the permeability of the soil-root matrix was sufficiently reduced. Planting lemon grass on soils located along slopes is recommended to improve its strength and minimize the ease with which water infiltrates the soil, thereby reducing the incidence of landslide and other water-induced types of slope failure

Free thaw resistance of stabilized and fiber-reinforced soil vulnerable to landslides

The research is undertaken to study the combined reinforcing and stabilizing effect of Eco sand, Metakaolin added with Polypropylene fibers in silty soil obtained from Nilgris district. In this work, an effort is made to obtain the impact of adding polypropylene fibers in fixed ratios (eco sand10%_metakaolin 5%) tandem with two novel stabilizing agents in various proportions (polypropylene fiber 0.1% & 0.2%) is the effects of non-traditional additives on the geotechnical properties of soils have been the focus of much investigation in recent years. It has been well established that the plasticity index and also the size, shape, and arrangement of soil particles will affect the treatment process of natural soils with additives. Stabilization of soils that are subjected to a regular variation in the temperature requires the most probable selection of suitable stabilizers and admixtures to improve the strength of the soil. This study investigates the resistance of the Nilgiris soil over the freeze–thaw reaction. The soil is stabilized with Eco Sand, Metakaolin, and polypropylene fiber (synthetic fiber). The index and engineering properties of the soil were determined in the laboratory. The soil is stabilized with two variants of an equal proportion of EcoSand-10%, Metakaolin-5%, and varying the polypropylene fiber in a proportion of 0.1% and 0.2% with the weight of the soil. UCS test was conducted for the virgin sample as well as the sample after four freeze–thaw cycles. The soil sample is kept at 0° for 24 h and later at 28° for 24 h to complete a cycle. It is determined that the admixtures added has increased the resistance of the soil over the freeze–thaw reaction after the cycles. The polypropylene fiber has increased the bonding of soil, and hence it stabilizes the soil during a large periodical variation in the temperature of the soil

Assessment of groundwater quality using spatial variation technique

Groundwater management is a potential solution to the global water crisis. We assessed the groundwater quality at Mettupalayam, Tamil Nadu, India, in order to determine its suitability for drinking. Groundwater samples were collected and their physicochemical characteristics such as pH, electrical conductivity (EC), total hardness (TH), total dissolved solids (TDS), Ca2+, Mg2+, SO42- and Cl- were determined and benchmarked with standard drinking water requirements. The variations of these parameters were presented spatially. The groundwater is generally brackish and hard; and of low alkalinity and high salinity. Consequently, the groundwater in most parts of the study area is unsuitable for drinking without treatment. It is recommended that point and nonpoint sources of groundwater pollution at Mettupalayam should be identified, monitored and managed in order to protect the groundwater

Freeze-thaw Resistance of an Alluvial Soil Stabilized with EcoSand and Asbestos-free Fiber Powder

Stabilization of poor soils subjected to large daily temperature variations requires careful selection of suitable stabilizer for improvement of such soils. This study investigated the freeze-thaw resistance of an alluvial soil stabilized with EcoSand and asbestos-free fiber powder (AFP). Physical and mechanical properties of the soil were determined. The soil sample was stabilized with 5 variants of equal mixtures of the EcoSand and AFP in proportions of 2, 4, 6, 8 and 10%, with 1% sodium silicate and 1% fly ash, by weight of the soil. UCS tests were conducted before and after three freeze-thaw cycles, while keeping the sample at 0ºC for 8 hours and later at 30ºC for 8 hours for each cycle. It was found that the 8% EcoSand + AFP with 1% sodium silicate and 1% fly ash content provided an optimized increase of the freeze-thaw resistance of the soil. The use of a mixture of EcoSand and AFP as a soil stabilizer for regions of the world experiencing large temperature variation has the potential to improve the resistance of sand to freezing and thawing

Studies on strength characteristics of black cotton soil by using novel SiO2 combination as a stabilizing agent

The rapid growth in industrialization and population leads to generation of large quantity of wastes, some materials were containing high silica contents is damped as a waste. In this study such damped silica wastes from various industries is collected and subjected to studies as a stabilizing material for black cotton soils, such assorted materials are Fly ash, GGBS, Rice husk ash, Precipitated silica and Calcium chloride. By effective nanoparticle studies like SEM, EDAX, presence of silica, aluminum and magnesium proportion in each industrial waste is formulated. From the result of nanoparticle analysis novel silica combination prepared by composition of all those materials based on cementanious action mineral presence. In before studies one or two combinations only used as stabilizer but in this paper a new group bearing binder combination is designed and their behavior with chosen geo material and its respective engineering, strength and hydraulic properties is studied by Constantine combination proportion to 20% to weight of soil. Properties such as California bearing ratio (CBR), and North Dakota of the soils were determined with the addition of stabilizers. From the results engineering properties of the poor engineering graded soil were improved is clearly visualized. For the normal soil and effective result binder proportion, a comparison in finite element analysis using PLAXIS is carried out for footing study. Finally, the study showed that exact cementanious mineral combination from industrial waste could improve the geotechnical properties of highly inorganic soil

Strength characterisation of self cured concrete using AI tools

Civil engineering experimentation process is termed to be a costly process when it involves destructive testing of materials to obtain their strength and durability. Testing of materials through destructive process is century old procedure, but recent decade science involves the prediction of strength and durability using alternative methods. One such method to predict the strength in nondestructive method is employment of Soft computing technologies, this process is gaining impetus in the recent decade due to its accuracy, reliability, and versatility. In this research, we had employed artificial intelligence tool to predict the compressive strength of concrete with available real time laboratory-based data. AI tools require a greater number of data to predict the results but in this work and attempt is made to predict using a smaller number of data with more accuracy. Compressive, flexure and tensile strength of concrete is predicted using ANN techniques (Levenberg-Marquardt (L-M) process and Bayesian regularization (B-R)). Two input parameters were only employed to check the real time accuracy with a model that has 12 input layers and 18 hidden layers incorporated. Model output shows regression values of 0.97428, 0.92865 and 0.96772, concerned with L-M algorithmic model and 0.96573, 0.95625 and 0.91787 for BR based model. Also, its observed that while using L-M algorithm the best performance was obtained at 1.3287 at epoch 2 for compressive strength and 0.12417 is achieved at epoch 1 for tensile strength and 0.021578 at epoch 3 concerned with flexural strength. Also with B-R algorithm provided best performance of 2.1488 at epoch 4 for compressive strength, a value of 0.43468 at epoch 3 for flexural strength and 0.015279 for tensile strength reached at epoch 30. Thus we propose the usage of ANN even with less number of data using this method for predicting the values of compressive strength of concrete. � 2020 The Authors. Published by Elsevier Ltd

Impact Resistance and Strength Development of Fly Ash Based Selfcompacting Concrete

The development of self-compacting concrete using alternative materials is expanding in recent years due to the technical and economic benefits of the mixture. This study focuses on the structural and compositional behavior of sodium hydroxide (NaOH)-activated fly ash based self-compacting concrete (SCC). Fly ash was partially replaced with Ordinary Portland Cement from 0– 30%. The tests performed on concrete samples include workability, strength, microstructural, and impact resistance. The results showed that activated fly ash reduces the heat of the hydration process of the concrete mixture but enhances pozzolanic reactions, which led to increased strength properties. The addition of activated fly ash modifies the mineralogy of the concrete, as evident in strength characteristics. The best performance of the activated fly ash based SCC, in terms of strength, was found at 10–15% substitutions, which can somewhat reduce the cost of production of SCC and strength improvement advantage

Fabrication of precast concrete slab panels incorporating foundry sand and blast furnace slag as a potential wall insulator

Increasing construction cost and environmental sustainability are persistent issues of concern in the built environment. Consequently, new generation materials are required for practical applications in order to considerably tackle the challenges. This work focused on the fabrication and testing of precast concrete slab panels produced using industrial by-products - foundry sand, as a partial replacement of fine aggregate, and ground granulated blast furnace slag as cement admixture. Foundry sand was substituted for manufactured sand in levels 0%, 10%, 20%, 30%, 40% and 50%, while granulated blast furnace slag (GGBS) was constantly added to cement at 30%, in a standard designed M40 concrete grade. The result showed that 40% of foundry sand was adequate for appreciable strength development in the modified mix. The same mixture was also found to have better insulation characteristics than the conventional mix. The wall panels tested in this study are quite economical when compared to competing building technologies

Shear Resistance of portal Frame Reinforced with Bamboo and Steel Rebar: Experimental and Numerical Evaluation

The main objective of this study is to evaluate the shear resistance of portal frame fabricated with bamboo and steel rebar by following experimental and numerical approaches. In support of sustainable construction, bamboo stripes were utilized as a partial replacement of steel rebar at tension zone of members that are subjected to lateral loading. The performance of nominal portal frame, which are fabricated with steel reinforcement was compared to the portal frames having several replacements of steel reinforcement with bamboo, in terms of seismic resistance and lateral load capacity. The experimental data was correlated based on software analysis using ABAQUS. The partial replacement of steel with bamboo under tension zone of the beams in portal frame was found to be highly effective, and also that the flexural rigidity of the partial bamboo reinforced frame was slightly higher than the nominal portal frame. This study provides insight on the possibility of reinforcing structural members with bamboo, when lateral loading is imminent on the structure