One of the key behaviours that predict the performance of portand cement system containing silica fume is hydration. Hydration affects the microstructure of concrete, which in turn alters its engineering properties such as strength, elastic moduli, toughness and other durability related properties like porosity and permeability. Therefore in order to predict such properties, fundamental study of the hydration process of portland cement system containing silica fume is very important. The main aim of the present investigation is to gain insight on the effects of silica fume addition on the hydration process and microstructural development of cement paste. This was done by adopting an integrated approach involving combination of theoretical models and experimental investigation, and developing mathematical equations to predict hydration behavior of the system. Quantitative studies on cement hydration is conducted using thermo-gravimetric analysis and other techniques, and qualitative studies is done using X-ray diffraction techniques. The non-evaporable water content and the calcium hydroxide content of paste obtained from experiments coupled with the use of suitable theoretical models is used to determine the degree of hydration, degree of pozzolanic reaction and calculated porosity for paste containing silica fume at different dosages of silica fume. (0%, 4%, 8% and 12%). Attempts were made to further understand the trends obtained using curve-fitting techniques and other theoretical models. Results from the study indicated that the addition of silica fume at all replacement levels depletes Ca (OH) 2 produced from cement hydration and forms C-S-H gel and this reaction starts at early curing periods. In addition, the non-evaporable water content and the fraction of silica fume that completely reacted decreases, with increase in its replacement level and helped in determining the degree of cement hydration and pozzolanic reaction of silica fume particles. A significant portion of unreacted silica fume remains in the paste and is involved in the pore filling process. The porosity values for paste containing silica fume decreased with increase in its replacement levels due to both its pozzolanic reactivity and pore-filling ability. The compressive strength data showed that mortars containing 4% and 8% replacement level of silica fume have higher strength than the control mortar. However, SF-12% mortars registered lower strength than the control. The trends obtained are reasoned to be due to variations in the amounts of primary and secondary C-S-H gel. Further, mathematical equations are developed through curve-fitting of experimental data, and analysis of these equations revealed that the effect of variation observable with control and SF-4% paste, and SF-8% and SF-12% are merely due to the dosage of silica fume while the effect of variation observable with SF-4% and SF-8% is due to the dosage of silica fume and other mechanisms associated with its dosage.

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The system explained in this paper provides a compact smart surveillance system. Recent years have seen the Internet of Things (IoT) dominating in various fields of applications. With devices getting smarter and insurgence of 5G technology, the connectivity of people with devices is increasing. Smarter surveillance systems are more reliable and accessible. A gyroscope is a MEM sensor which detects angular disturbances. The principle is to detect opening or knockdown of the door physically or by a gas cutter. The system is connected to the user via Wi-Fi using ESP8266. Being a system with a low form factor, this system can be implemented on doors, shops, cars, etc. An alarm system is included in the system to alert the neighbors as well as to send a notification to the user via Blynk mobile application. The proposed system is a portable smart home solution for theft detection.

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In any manufacturing process, surface roughness is a common parameter for quality and customer satisfaction. Customers will satisfy based on the physical appearance of a manufactured product. The surface roughness value of the machined product is depend on the different machining parameters like speed, feed, depth of cut (DOC), coolant flow rate etc. Many researchers have done their work in this field to achieve the minimum surface roughness value by optimizing the machining or process parameters in end milling. In this paper presented is the description of feed for milling and the CNC milling process.

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In this work, an attempt has been made to carry out an experimental work, based on various results with different amount of additives ranging from 0% to 4 % (RBI Grade-81) and 10% to 50% (Stone Dust). The additives used are RBI Grade-81 and Stone Dust. Different properties of soil are determined for the soil. The important soil parameters are determined by incorporating different percentages of RBI Grade-81, Stone Dust and (RBI Grade-81+ Stone Dust). Then a more economical wise and CBR value wise 40% of Crushing Dust and 2% of RBI Grade -81 is suitable for pavement thickness.

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While working in high earthquake-prone areas, seismic analysis of any type of structure with various porch locations is an important consideration. The structure can be designed and built to withstand the high lateral movement of the earth's crust during an earthquake with the help of seismic analysis. Porch placement is critical for any tall structure, not only in terms of aesthetics but also in terms of structural loading. The current job, which is part of the tall structure's innovative phase, involves the analysis and design of a tall structure subjected to seismic load conditions with various porch locations. The earthquake loads are applied to the structure in addition to the dead load and imposed load, and a structural analysis is performed. Design and analysis were carried out using design software. In the current situation, a hospital building structure of G+12 has been analysed for seismic zone III using Response Spectrum Analysis in accordance with IS 1893-2016. The results of Displacement, Storey Shear, and Base Shear, among others, have been assessed. For the seismic zone, the results are obtained and represented in the form of graphs and tables.

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