Nanomodification of Lightweight Fiber Reinforced Concrete with Micro Silica and Its Influence on the Constructive Quality Coefficient

A hypothesis was put forward that a nano-modifying additive of micro silica, which had a beneficial effect on achieving a perfect structure of heavy concrete, can also be effectively used in lightweight fiber-reinforced concrete. The nano-modifying additives of micro silica application in manufacturing lightweight fiber reinforced concrete products and structures can significantly enchain their strength characteristics without increasing their mass and consequently improve their design characteristics. The purpose of the work was to increase the structural quality coefficients for all types of strengths of lightweight fiber-reinforced concrete due to its modification with micro silica. The effect of nano-modifying additives of micro silica on the strength characteristics of lightweight fiber reinforced concrete was studied. The optimal amount of micro silica addition was experimentally confirmed and established of 10% of the cement mass. The coefficients of constructive quality for all experimentally determined strength characteristics of lightweight fiber-reinforced concrete modified with micro silica additives were calculated. The coefficient of constructive quality for tensile strength in bending of lightweight fiber reinforced concrete with additives was two and a half times higher than that of heavy concrete without additives and up to 37% higher than that of lightweight fiber-reinforced concrete without additives.

A Study on Strengthening of Concrete Structures

Concrete is the most commonly used building material due to its high strength, moldability, weather-resistant, and fire resistance, among other benefits. In recent years, there has been a growth in the usage of Micro Silica fume. Through the Ore sand Bridge building, records show that Micro Silica was used in the concrete. These fabrics are not only environmentally sustainable, but they also have technological advantages on both new and hardened mortar products. Both goods are agricultural by-products, but their usage decreases the amount of primary raw materials removed from the earth. Latent hydraulic content is micro silica fume and fly ash. It has intrinsic cementation effects, which must be activated. Combining the powder with Portland cement is a popular way to achieve these results. Pozzolana is the name given to pulverized fly ash. These materials may not have intrinsic cementation properties, but a cementation substance is created when mixed with a high alkaline material.

A Study on Strengthening of Concrete Structures

Concrete is the most commonly used building material due to its high strength, moldability, weather-resistant, and fire resistance, among other benefits. In recent years, there has been a growth in the usage of Micro Silica fume. Through the Ore sand Bridge building, records show that Micro Silica was used in the concrete. These fabrics are not only environmentally sustainable, but they also have technological advantages on both new and hardened mortar products. Both goods are agricultural by-products, but their usage decreases the amount of primary raw materials removed from the earth. Latent hydraulic content is micro silica fume and fly ash. It has intrinsic cementation effects, which must be activated. Combining the powder with Portland cement is a popular way to achieve these results. Pozzolana is the name given to pulverized fly ash. These materials may not have intrinsic cementation properties, but a cementation substance is created when mixed with a high alkaline material.

Experimental Studies of Marble Concrete Prepared with Micro Silica and Rice Straw Ash

This experimental study is about the investigation of the concrete prepared with marble waste, micro silica and Rice Straw. Investigation is done by determining ad comparing the mechanical Strength properties and cost of Proposed concrete with the Normal conventional concrete. The different test on the marble concrete shows that the incrment in marble powder content increases the mechanical strength of concrete. Marble is costlier than the Coarse aggregate, so it also increases the cost of the concrete. Micro silica fills the voids in the concrete and helps in the increment of the strength. After the replacement of recycled aggregates and addition of the silica fume, Rice Straw ash can replace cement by 15% without any decrement in the strength of the concrete. Total water absorption of the concrete Decreases due to use of marble because it does not absorb any water.

Understanding Variations in the Tracking and Erosion Performance of HTV-SR-Based Composites due to AC-Stressed Aging

Among the polymeric family, high-temperature-vulcanized silicone rubber (HTV-SR) is the most deployed material for high voltage insulation applications. However, in an outdoor environment, due to contamination and wetting-induced dry band arcing, consequently SR experiences surface tracking and erosion. From a practical standpoint, the tracking and erosion performance under multi-stress aging is required to be known. It is in that context that the present study was undertaken to measure and analyze the effect of multi-stress aging on tracking and erosion performance. Composite samples of SR having different filler concentrations of silica and alumina trihydroxide (ATH) were aged in a multi-stress chamber for a period of 5000 h, and after that their electrical tracking performance was studied. Simultaneously, unaged samples were also exposed to tracking test for comparison. To conduct this test, the inclined plane testing technique was used in accordance with IEC-60587. All samples exposed to tracking test were analyzed using different diagnostic and measuring techniques involving surface leakage current measurement, Fourier transform infrared spectroscopy (FTIR), thermal stability and hydrophobicity classification. Experimental results shown that the tracking lifetime increased through incorporation of silica and ATH fillers in the SR. Amongst all test samples, two samples designated as filled with 2% nano silica and 20% micro silica/ATH exhibited greater resistance to tracking. This was attributed to the optimum loading as well as better dispersion of the fillers in the polymer matrix. The presence of nano-silica enhanced time-to-tracking failure, owing to both improved thermal stability and enhanced shielding effect on the surface of nanocomposite insulators.

Assessment of chemical exposures on ECC containing stone slurry powder

Generation of solid waste materials from various industrial sources is becoming a challenging issue for safe disposal. Durability performance of hydraulic structures under environmental loadings (aggressive substances) is also a concerning issue. The present paper investigated the durability performance of engineered cementitious composite (ECC) mortar containing stone slurry powder (SSP). SSP was used as partial subrogation of micro silica sand (MSS) and fine sand (FS) by 25% and 50% for each type of sand. Electrical resistivity (ER), compressive and tensile behaviour of various mixes were studied experimentally under chloride, sulphate and chloride-sulphate combined environmental conditions. Results obtained from various properties revealed that performance of fully MSS and FS containing ECC mixes was affected under aggressive substances at initial stages. The observations demonstrate that ECC containing SSP was durable and maintains better mechanical performance over fully MSS and FS containing mixes. This improvement finds a place in construction of hydraulic structures under aggressive environments.