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A systematic correlation is established between the axial load-carrying capacity of the socketed piles and empirical methods. The axial load-carrying capabilities were calculated with the help of pile load tests for ten single piles in Navi Mumbai, India. Pile load tests were carried out to evaluate the skin friction and base resistance in overlying soil and rock. The test results of axially loaded bored piles socketed into the rock are mentioned in this paper. The pile socket involved rocks of various strengths such as gypsum, limestone, and basalt. In reality, axial capacity is calculated from skin friction of the pile, which occurs owing to a very small settlement in the rock socket. The unconfined compressive strength of the rock is collected from the laboratory test. The load-bearing capability of the socketed piles is determined using several empirical methods, which are usually evaluated by a back-assessment of the in-situ pile load test. However, the significant load-carrying capacity values derived from empirical correlations are found to be reasonably good compared with those estimated from pile load tests. [ABSTRACT FROM AUTHOR]

• Novel analysis of attenuation the growth of Aspergillus tamarii on concrete using radiation in the field of conservation of heritage building. • UVC and gamma irradiation decreased the leaching of calcium ions from concrete when infected with A. tamarii. • Increase in compressive strength of concrete cube was observed to be the most in irradiated cubes. • Effect of A. tamarii and low dose radiation led to less deterioration of concrete (except higher dose) than only exposure to A. tamarii. The conservation of concrete-based deteriorated heritage buildings is a big challenging issue worldwide including in India. This study focused on to prevent fungal biodeterioration in concrete using UVC and gamma radiation. M20 graded concrete cubes (5 cm × 5 cm × 5 cm) were infected with Aspergillus tamarii , which was isolated from a 200 years old historic heritage building. M20 signifies a mixture of cement, sand and aggregate (1:1.5:3), made in such a way that the concrete cube has a compressive strength of 20 N/mm2 when examined after 28 days of curing. The fungal growth appeared clearly as calcium oxalate crystals in the Scanning Electron Microscope (SEM) photographs. Several doses of UVC and gamma radiation were applied on concrete cube. The changes in concrete properties were examined after 30 days in terms of weight, compressive strength, Fourier Transform Infrared Spectroscopy (FTIR) and micro Energy Dispersive X-ray Fluorescence (EDXRF). The results exhibited that compressive strength of control (non-infected and non-irradiated), biodeteriorated (infected), UVC (625 µw/cm² × 300 s) and gamma (0.5 KGy) irradiated infected (inhibition) concrete cubes were 19.74 ± 0.46, 18.88 ± 0.43, 20.20 ± 0.34 and 19.93 ± 0.20 N/mm2 respectively whereas negligible weight losses were observed for inhibition cubes compared to biodeteriorated ones. Calcite (1400, 874 and 705 cm−1), one of the major functional band present in concrete became weak after getting infected by Aspergillus tamarii and strong for inhibition samples irradiated with the above doses. The EDXRF analysis exhibited that mass percentage of calcium ions of the biodeteriorated concrete cubes (49.88 ± 0.65%) was lower than that of UV (75.75 ± 0.16%) and gamma (70.95 ± 0.30%) irradiated infected or inhibition concrete cubes. Altogether, the efficacy of the recommended inhibitory dose of ultraviolet and gamma radiation against concrete deterioration in the field of conservation of heritage building was observed to be positive. [Display omitted] [ABSTRACT FROM AUTHOR]

Sustainable development goal 6: clean water and sanitation—could be a big challenge for water-stressed India. Use of non-potable water for concrete production can contribute largely towards this goal. Scattered experimental studies on concrete mixed with non-potable water having different pH, were collated to prepare a pan-Indian database. Using this data, probability of code compliance of Indian concrete for varying ranges of pH value of mixing water, within the limits permitted by the Indian code (6–8.5), were estimated for the first time in India. A bootstrap-based re-sampling approach was employed for this purpose. The results indicated that fulfilling the 28-day strength requirements would possibly concurrently fulfill similar stipulations for 7-day strength for Indian concrete mixed with non-potable water of varying pH. However, the probabilities of meeting the Indian code requirements were between 54%-66% for pH ranges starting from 6; and between 66%-85% for others (95% confidence). Considering the entire range of pH (6–8.5), this probability was 66% for 28-day and 72% for 7-day (95% confidence). Probabilistic approach for examining the strength/setting time compliance, along with inclusion of 7-day strength as well as durability aspects in future experiments would help to promote use of non-potable sources of water and reduce use of freshwater for mixing concrete in India. [ABSTRACT FROM AUTHOR]

Introduction: Direct Pulp Capping (DPC) aims to retain the pulp's health by sealing it against microbes and stimulating the formation of a dentin bridge at the exposure site. It has been proven that natural antimicrobial proteins, when used as therapeutics in conjunction with traditional chemotherapeutic agents, have increased efficacy and presumably diminished the incidence of chemoresistance. Hence, the efficacy of Bromelain with Biodentine and Biodentine as isolation materials for DPC will be evaluated and compared in the present study. The success and durability of DPC depend on the type of material used. Thus, the present study focuses on evaluating and considering a combination of materials for DPC that can be used in clinical practice. Need for the study: By addressing the limitations of current materials and formulating a novel combination, the present study aims to contribute to the advancement of material science, providing solutions that meet the demands of this era. Such a breakthrough would not only enhance the performance and longevity of materials but also have a significant positive impact on the preservation of pulp vitality, promoting overall well-being and improved outcomes in healthcare applications. Aim: To evaluate and compare the efficacy of Bromelain with Biodentine and Biodentine in isolation as DPC materials. Objectives: The study aims to evaluate and compare the setting time, flow, solubility, compressive strength, adhesion, and radiopacity of bromelain with biodentine and biodentine in isolation. Materials and Methods: An in-vitro study will be conducted in the Department of Conservative Dentistry and Endodontics at Sharad Pawar Dental College and Hospital, Wardha, Maharashtra, India, for a duration of nine months from May 2023 to February 2024. Standard discs of freshly mixed materials (n=10 samples per material) will be prepared. Compressive strength, solubility in distilled water, setting time, flow, radiopacity, and adhesion of Bromelain with Biodentine and Biodentine in isolation will be evaluated and compared in accordance with the International Standard ISO 6876:2001. Results will be analysed using Tukey's Honest Significant Difference (HSD) posthoc test, one-way Analysis of Variance (ANOVA), and student's t-test. [ABSTRACT FROM AUTHOR]

Because of urbanization, demand for housing is increasing day by day in India. Traditional clay brick leads to resource scarcity and environmental pollution. To overwhelmed this problem, manufacturing of bricks was done using the waste of thermal power plants like Fly Ash along with Sand and Cement (FAS-C Brick) as key ingredients. Fly ash is an Industrial by-product of thermal power plant. An experimental study of mix-design was carried out to increase the quality of the FAS-C brick. This paper attempt to formulate the mix design of fly ash based brick by process planning. Laboratory tests were conducted to determine the compressive strength and water absorption of the bricks. The main objective of the research study was to design the Fly Ash, Sand, Cement (FAS-C) brick and find the compressive strength using different mix design methods as a part of quality improvement process. [ABSTRACT FROM AUTHOR]

The July 12, 2016 Tombinoutek landslide along state highway between Imphal and Jouzangtek village, Manipur, India affected the road section for a stretch of ∼475 m. The research aimed at finding the combined effects of topography, lithology and structural attributes of the landslide. Detailed geodetic survey was carried out using drone supported by ground control points obtained by total station survey. Base map with 5 m contour intervals, slope and aspect maps prepared; critical slope is between 45° to 60°. Geological studies have shown occurrence of intercalated sandstones and dissected shale, disturbed by five prominent joint sets which play an active role in the initiation of the landslide through plane and wedge failures. Geotechnical analyses of sandstones indicated strong compressive strength ranging between 80 and 97 Mpa, and tensile strength of sandstones and shales between 17 and 20 Mpa and 2.62 and 3.27 Mpa respectively. Soil analyses showed plasticity index (IP, percentage) of 10.66, and liquid limit (WL%) of 32.5. Average soil porosity is 80%. Liquidity index of -1.208 indicates relatively stable condition under dry condition. Plasticity index of 10.66 lies in the CL field, close to the boundary between low plasticity and medium plasticity. Sandstones show fair rock RMR with class IIb stable SMR, and shales show poor rock RMR with class IIIb partially stable SMR. [ABSTRACT FROM AUTHOR]

Evidence of frictional melting in the form of pseudotachylite is innumerably found along the Gangavalli fault zone (GFZ), southern India. Such catastrophic deformation influences the strength of rock masses across the fault zone. In this paper, we have investigated the strength variation in fault zone rocks during post-seismic deformation. The experimental study suggests that the average uniaxial compressive strength (UCS) for pseudotachylite hosting charnockite (i.e., Pt-charnockite) is almost double (45.58 MPa) as compared to the pseudotachylite devoid charnockite (i.e., D-charnockite) of 24 MPa. The melt associate seismic deformation shows high stress drop due to melt lubrication at the fault interface and simultaneously produced numerous fractures in the rock. We have determined the stability and denseness of both rock types using acoustic emission (AE) technique that remarks a distinct difference in AE signatures. The analysis indicates a more stable and dense Mogi type-III signature for post-seismic deformed rocks that are assisted by pseudotachylite melt. However, negligible AE energy is observed in the D-charnockite. We proposed that the melt-assisted seismic deformations are more inhibitable to reactivate the slip surfaces than the conventional earthquake-deformed rock having no melting phenomenon and therefore, pseudotachylites enhance the strength of fault zone rocks during post-seismic deformation. [ABSTRACT FROM AUTHOR]

The study considers the impact of the degree of weathered material constituting the sedimentary rocks on the strength of the Lower Gondwana coal measure rocks. The dependence of the strength of primary rocks on the alteration indices has been previously studied, but it is unknown for secondary/sedimentary rocks. Therefore, in this paper, Lower Gondwana coal measure rocks (sandstone and shale) from the most productive coalfields of India, the Barakar and Raniganj coalfields, have been studied geochemically and geomechanically to find out their correlation. Geochemically, the study revealed that an arid, non-marine, and deltaic depositional environment prevailed during the sedimentation of Barakar and Raniganj Formations. The provenance was deduced to be mafic igneous. It was also deduced that the Lower Gondwana sandstone is clay-rich, and the sandstone samples fall in the shale field in the chemical classification scheme for terrigenous clastic sediments. The weathering indices, along with the uniaxial compressive strength (UCS) of the Barakar and Raniganj Formation coal measure rocks, have been assessed. The dependence of UCS on the weathering indices has been evaluated, and positive relationships were obtained. [ABSTRACT FROM AUTHOR]

Physical, chemical, and mineralogical characterisation of as-received rice husk ash (RHA) samples sourced from four rice-growing regions (North, South, East, and West) of India is presented. Valorised RHA was obtained through controlled combustion at two temperature ranges (600–700 °C and 650–700 °C) of husks from the North in an industry set up. Valorisation efficacy has been tested through comparative characterisation of the valorised RHAs with the as-received RHAs from the four regions. Blending of 15% valorised RHA (in the beneficiated state) by weight of cement had no adverse effect on compressive strength even though water–binder ratio of the blended mortar had to be increased by 14% to achieve flow of the control cement mortar. Compared with the control cement mortar, porosity of the mortar blended with the beneficiated RHA measured using mercury intrusion porosimetry (MIP) increased by up to 10% primarily due to an increase in the number of large mesopores (0.01–0.05 µm). [ABSTRACT FROM AUTHOR]

Physical properties of rocks have significant engineering value. Compressive strength and density of rocks are used in many rock mechanics related studies pertaining to civil and mining activities, stability of the excavations and estimation of the support required. In addition, rocks like granite are used as a building material and are encountered in many civil and infrastructure projects. However, these properties vary with increase or decrease in their temperature. A host of data exists on heat treatment of different rocks. In order to augment such studies and to further the know-how in this discipline, a comprehensive analysis of 56 samples of two types of granites from India was taken up in this study. The tests for compressive strength and density with increase in temperature from 35°C to 600°C were devised and conducted. The results revealed that the behaviour of two groups of the granite varied in a noticeable range on a linear scale. A reduction of 45% to 49% in strength from room temperature to 600°C in the two types of granites points to the loss of strength with increasing temperature. A reduction of 4.3% to 6.3% in density of the samples on heating can be considered to be mild. The rearrangement of grains, loss of water content initially and increase in volume on further heating are considered to be the major reasons for reduction of such physical properties in a linear manner. Colour changes have also observed in the heating process which needs to be explained in future. [ABSTRACT FROM AUTHOR]

Fascinating share from specific natural additives are used during the formation of constructions and paths. From them, hazardous gases are departing. These gases are crucial to the variance in the earth's atmosphere. Cannabis Sativa, gokshura are natural resources(carbon negative material) from the medieval period are using essentially like a cheap environmental bearing substance against numerous composite commodities. Within structures, this is frequently practiced, including a lime filler cover inside drywall structures. Some precise data ready to judge the atmosphere behavior of here kind of structure in India, UK. Here analysis strives to recognize the methods and supplies associated with the development of cannabis sativa, chrysopogen zizanoides walls blended with lime and strengthening their maturity classification impact upon climate alteration. This research obeys methods including guidelines regarding worldwide (ISO14040) and UK (PAS2050) measures. We will execute cannabis Sativa -lime drywall frame is 1m2 in range, 315 millimeters including wood framing brace internally. The investigated parts of hempcrete consolidate characteristics of hemp appropriate to development, binder qualities, mechanical properties, sturdiness, and melting properties, natural qualifications, fabricating cycles, and current applications. A few exploration gaps concerning the hydraulic nature of the binder, strength, and sturdiness, and burning obstruction of hempcrete were verified. This was additionally settled that hempcrete has remarkably moderate embodied carbon, some other gases and encapsulated power, addressing it absolute for natural additive structure pertinence. The conclusion closes with a conversation illustrating the demand and aiming for future examination on enhancing the amount of co2 other greenhouse gaseous sequestration from natural additives while blending with lime and also to increase compressive strength of lime. [ABSTRACT FROM AUTHOR]

The carbon dioxide produced by cement industries causes environmental pollution and global warming. In 1000 Kg of cement manufacturing processes, approximately 900 Kg of CO2 is emitted. In order to reduce the impact of cement production on atmosphere, waste bi-products are used as admixture. In India, every year 75 million tons of fly ash, which are rich in silica, are disposed to landfill as waste. Also, Egg Shell Powders (ESP), which are rich in calcium, are thrown away as waste. In the paper, these two wastes are used as a partial replacement of cement, and various properties like workability, compressive strength, split tensile strength and flexural strength are studied. ESP was varied up to 15.0% (0%, 2.5%, 5%, 7.5%, 10%, 12.5% and 15%) and fly ash was added to cement from 0% to 30% (0%, 5%, 10%, 15%, 20%, 25% and 30%). The results further showed that addition of fly ash along with ESP is beneficial for improved performance of concretes. [ABSTRACT FROM AUTHOR]

Induration of ilmenite pellets by oxidation is an essential step in the pelletization process since it decides the physical and metallurgical properties of the pellets. In this regard, the induration parameters such as temperature and roasting time have been optimized to obtain good quality ilmenite pellets made of concentrates obtained from low-grade ilmenite ores of Odisha, India. The oxidation temperature of 900 °C at a short roasting time of 15 min has been found suitable to achieve recommended requirements of various pellet properties such as cold compressive strength, porosity, metallization, tumble, and abrasion indices. X-ray diffraction and microstructural analysis indicate that the recrystallization of hematite in the oxidation process improves the mechanical strength of the pellets. In contrast, the formation of ferric pseudobrookite phase at 1000 °C and 1100 °C oxidation temperatures impairs the pellet strength. Unlabelled Image • The readiness of the ilmenite pellets for the reduction process was assessed through induration studies. • Different metallurgical properties were analyzed as a function of temperature and time. • Desirable pellet properties were attained at a temperature of 900 °C and a period of 15 min. • The phases changes occurred during induration were clarified using in-depth XRD, SEM, and EPMA analyses. • The oxidation mechanism of ilmenite pellets was correlated to the pellet consolidation. [ABSTRACT FROM AUTHOR]

Marble stone is the mostly quarried stone in Rajasthan for its high demand in India and abroad. This quarrying resulted in the generation of waste in a slurry form which was dumped in the nearby landfill sites resulted in a detrimental effect on the soil strata and expanding the landfill area with time. The focus of the study is to explore the outcome of utilization of marble slurry as a partial substitution of ordinary Portland cement by 10%, 20%, 30%, and 40% for lean concrete mixes with an average target compressive strength of 20 MPa or more. To explore the prospect of deployment of marble slurry in cement concrete mechanical properties, durability aspects, and relevant microstructural analysis was performed, and the results have been reported. Though the durability aspect was not purely encouraging, though it was depicted that marble slurry can be utilized as a partial replacement of OPC up to 40% for the purpose for which the investigation has been done. Highlights: Marble slurry utilized as a substitution of OPC by 10%, 20%, 30%, 40%.TGA results indicate that marble slurry did not affect the hydration of OPC.Resistance against carbonation decreases with the increment of marble slurry content.UPV results indicates after 40% substitution concrete was in the good quality zone. [ABSTRACT FROM AUTHOR]

Portland pozzolana cement (PPC) and ordinary Portland cement (OPC) OPC-53 grades of cement are commonly used in India. The thermal responses of these types of Portland cement (PC) differed upon analysing the compressive strengths of their hydrated cement block specimens at elevated temperatures. At 800°C, PPC was able to maintain the integrity of the cube, while OPC-53 failed to do so at 500°C. Thermal analyses were performed to interpret the performance of these two types of PC, and four critical regions of interest, – namely, 100°C, 400°C, 500°C and 800°C – were selected. X-ray diffraction and carbon hydrogen nitrogen sulfur-oxygen elemental analysis were conducted on both cements, and variations in the elemental and phase percentages were observed. The number of pores in OPC-53 was 4·51 times greater than that in PPC at 800°C. Additionally, relatively small pore radii ranging from 2·54 μm to 34·80 μm were observed for OPC-53 at 400°C; however, PPC contained pores with radii ranging from 2·54 μm to 67·23 μm. Ultimately, the development of micropores constitutes one of the primary reasons for structural collapse. [ABSTRACT FROM AUTHOR]

The extraction of marble and its processing as marble blocks is most common in several states of India. But the extensive growth of this industry has put adverse impact on the environment because of the production of huge amount of marble waste during extraction and processing. This experimental study highlights the impact of use of marble waste on the properties of lean concrete mix designed for the production of bricks. The basic objective of this experimental programme is to replace river sand in concrete by an optimum combination of quarry dust and marble waste in order to extract best performance in terms of strength and durability parameters. By varying the percentage replacement of fine aggregate with marble waste (0–100%), six concrete mix proportions were prepared for experimental purpose. The result shows that all these properties improved for complete substitution of fine aggregate with marble waste. It was found that compressive strength and flexural strength increased by 84% and 18.6%, respectively. The mixes were less reactive to the aggressive agents also. These advantages were derived due to the ability of marble fines impart necessary cohesiveness even at lesser water content which resulted in an impermeable microstructure. [ABSTRACT FROM AUTHOR]

The study emphasizes on physico-chemical, mineralogical, morphological, and mechanical characteristics of Coal Combustion Residues (CCRs) collected from two different thermal power plants. To determine utilization potential and valorization, specifically in the Indian cement sector more than governing guidelines of Indian Standards (IS), collected CCRs (Fly and Bottom Ash) samples were analyzed for physical, chemical, and mechanical characteristics. The characterization included pH, moisture content, acid insoluble residue, chlorides, reactive silica, LOI, carbon, Blaine fineness, XRF, SEM, XRD, FTIR, initial and final setting time, consistency and soundness, lime reactivity, and compressive strength at 7, 28, and 90 days. The characteristics were analyzed and selected with a view to determine their suitability as mineral additives in the cement sector. The study showed that; collected CCR samples fulfill the requirements of the Indian standard (IS:3812) as well as ASTM C-618 for physico-chemical and mechanical characteristics and show potential for increased use in the cement industry as mineral additives. The study also highlights that; up to 30% CCRs can be used as a mineral additives during cement manufacturing, and if long-term strength is considered up to 50% replacement can be possible. [ABSTRACT FROM AUTHOR]

Policy makers in India have realized the importance of facility for pedestrians and non- motorized vehicles in an urban infrastructure setup. This has resulted in increased utilization of construction materials like Portland cement and crushed stone, which are not environmentally friendly and sustainable. The current study presents the development of paver blocks for pedestrian facility using different wastes. Geopolymer concrete was synthesized by fly ash and recycled asphalt pavement aggregates for making of paver blocks. Paver blocks were produced in laboratory with recycled asphalt pavement aggregate replacement levels of 0%, 20%, 40%, 60% and 80% by weight of virgin coarse and fine aggregates. The developed paver blocks were tested for dimensions and tolerances, water absorption, compressive strength and abrasion resistance as per IS15658:2006 standard. The results of the laboratory study show that recycled asphalt pavement aggregates can be introduced into geopolymer matrix to produce paver blocks of desirable quality. Furthermore, its use in pedestrian facilities provides a new avenue for managing the excessive waste, which otherwise goes in landfills, incurring loss to the paving industry. Therefore, the proposed method can help decision makers to effectively utilize recycled asphalt pavement in paving industry with environment-friendly approach. [ABSTRACT FROM AUTHOR]

The Indian National Gas Hydrate Program Expedition 02 (NGHP-02) was the most comprehensive gas hydrate drilling expedition carried out to date. From 74 pressure cores that were successfully recovered from various site locations offshore India, 19 subsamples were obtained for further detailed geotechnical analysis using the PCATS Triaxial apparatus to investigate the geomechanical behaviour of the cores, including small-strain stiffness, G max , undrained shear strength, S u , as well as direct-flow measurements of permeability, k. Samples tested included fine-grained muds with no appreciable hydrate through to coarse-grained sands that contained extensive hydrate within the pore space. Although the subsampling and transfer of pressure cores into the PCATS Triaxial under zero effective confining stress, σ′ , remains challenging, 12 samples were successfully transferred and underwent detailed geotechnical characterization. During consolidation, after reapplication of in-situ σ′ , all samples experienced axial and radial consolidation, with variations between samples seemingly dependent on the degree of sample disturbance, stress relaxation between coring and testing, hydrate saturation, S h and grain size, D 50. The largest values of G max were obtained from samples with high S h in the pore space, with values much higher than that expected for similar sediments without hydrate under comparable σ'. Samples with high permeability had both high S h and larger grain size, suggesting that in coarse-grained sediments sufficient pathways are available for reasonable fluid flow even with high hydrate saturations. Triaxial testing and unconfined compression tests highlighted the influence of hydrate on increasing sediment strength, although the size of the sediment grains appeared to have an important control on the magnitude of the strength increase and the overall stress-strain behaviour. The results from the detailed geotechnical characterization of the recovered pressure cores will be invaluable in helping India identify potential locations for future gas production wells, and assess the long-term performance of such reservoirs. • Testing of pressure core samples using PCATS Triaxial apparatus was undertaken. • Induced strains during consolidation are influenced by test and sample conditions. • Permeability of hydrate-bearing sediments are greater than fine-grained sediments. • Hydrate cement increases strength/stiffness of coarse-grained sediments. • Increases in strength/stiffness influenced by grain size and clay content. [ABSTRACT FROM AUTHOR]

The knowledge about the utility of fly ash is well known worldwide. Moreover, even though fly ash is widely and abundantly available in India, its optimal utilization is not yet achieved. This paper attempts to give clarity on the viable limit of fly ash in structural concrete. The study confirms the applicability of efficiency factor method in the mix design and strength prediction of concrete. Maximum usable fly ash percentage depends upon the strength of concrete and type of chemical admixture. Although the results presented herein may vary with change of constituent materials, type of concrete, type and power of concrete mixer, ... etc., the trend in results would remain similar and will be useful for both researchers and practicing engineers in concrete technology domain striving for sustainable construction. [ABSTRACT FROM AUTHOR]

For practical reasons, it is typical for different types of sheathings (referred to as dissimilar) to be connected at both flanges of the stud (lipped channel-section) in cold-formed steel (CFS) panelized construction (e.g. one side has interior sheathing and the other exterior sheathing). However, limited studies are available on the axial behaviour of CFS studs with different combinations of sheathings present at both-flanges of a stud. This novel experimental study investigates the structural behaviour of nineteen (19) CFS panels with sheathing on one side only and different sheathing on both flanges of the wall panel using combinations of eight (8) different sheathing board types [fibre-cement boards (FCB) (8 mm/10 mm/12 mm thick); calcium silicate boards (12 mm thick); orient strand board (12.5 mm thick); and heavy duty FCB (6 mm/9 mm/12 mm thick)]. Also, first time an attempt is made to study the effect of dissimilar configuration using eight (8) different sheathing board types on axial strength of CFS panels in India. Experimentally tested single stud wall panel specimens consist of; one bare single-stud; eight (8) specimens sheathed with different types of sheathing boards on one flange only; and ten (10) specimens with combinations of different sheathing boards on both-flanges. Average test results are obtained by performing two (02) tests for each specimen. The strength enhancement of a bare single-stud from the sheathing boards has been investigated by testing specimens with a single layer of sheathing at one-flange and combinations of different sheathing boards on both-flanges. The ultimate axial compressive strength, load–deformation behaviour and failure patterns are the parameters compared. A new analytical and semi-analytical design methodologies namely; Rayleigh–Ritz (R-R) method and finite-strip method based on direct strength method (DSM) are adopted for evaluating the axial compressive strength of the CFS wall panels with dissimilar sheathing. Limited studies are available to verify the efficacy of R-R method and DSM to estimate the axial compressive strength of CFS wall panels with dissimilar sheathing on both flanges. Results establish that DSM may be used efficiently rather than the R-R method for axial compressive strength prediction of dissimilar sheathed CFS wall panels. The predicted values show good agreement with the experimental test results, and therefore, demonstrate that the semi-analytical method may be applied efficiently in design. • First time an attempt is made to study the axial compressive behaviour of CFS panels with dissimilar sheathing in India. • A total of 19 axial compressions tests were carried out on single-studded CFS wall panels with dissimilar sheathing. • Bare stud, one-flanged and both-flanged specimens using 8 different sheathing boards were considered for testing. • Tests were carried out on sheathing boards to evaluate the modulus of elasticity and peak deformation at failure. • Performance assessment of the Rayleigh–Ritz and Direct Strength Method is carried out using the experimental results. [ABSTRACT FROM AUTHOR]

Mine overburden removed during surface mining is considered as “waste” or “spoil” that is consuming a vast tract of land for storage. Due to high ash content (30–50%) of Indian coals, 130 million tons of fly ash per year is generated with less than 50% of it is being used. Many a time thermal power plants are close to coal mines. Hence, in the present study it is proposed that a mixture can be prepared using fly ash and coal mine overburden with or without cement, which can be used as a stabilized pavement material. The present study deals with characterization of cement stabilized mine overburden fly ash mixture as a pavement material. Mixtures with varying cement percentage of 4–7% were prepared. Based on the unconfined compressive strength and California Bearing ratio values of the stabilized mixture, it was observed that it can be used as a stabilized pavement material. [ABSTRACT FROM AUTHOR]

• Indian finely grounded waste glass powders (GP) recycling in M30 and M40 grade concretes. • GP as cement replacement from 0 to 40%, steps of 10% • Workability, compressive strength and durability indicators improved with the increased of GP content. • Increased drying shrinkage with GP content, still within standard limits. • 30% GP as cement replacement provides optimal engineering properties for conventional concretes and paver concrete blocks. Waste glass is a significant concern in India, and management solutions seek. Finely ground waste glass (GP) presents pozzolanic properties, which make it potential for concrete applications as cement replacement. The main feature of the present work lies in the simultaneous incorporation of two GPs with different fineness, generated from consumer scrap in India, as cement replacement in equal proportions, from 0 to 40 %, in two concrete grades, M30 and M40. An experimental programme was carried out, including fresh, shrinkage, mechanical and durability properties. GP concrete specimens showed compressive strength and a slight improvement for both concrete grades compared to reference concrete specimens (0 % GP incorporation). The durability indicators, namely, water absorption, sorption, chloride-ion penetration and moisture movement in GP concrete, improved with the increase of GP content. The drying shrinkage increased with the rise in GP content; however, the results still fit the permissible standard limits. Optimal concrete mixtures were selected to further study GP incorporation in concrete paver blocks. Four concrete paver block types were produced, including M30 and M40 with no GP (0 %GP) and M30 and M40 with 30 % GP as cement replacement (15 % GP1 + 15 % GP2). The compressive strength of the concrete paver blocks with GP significantly improved. Thus, the concrete with 30 % partial cement replacement by GP is a potential option for the construction industry while providing a management waste solution and contributing to a circular economy. [ABSTRACT FROM AUTHOR]

Utilization of reclaimed asphalt pavement (RAP) in the construction industry is gaining an advantage over conventional materials in terms of sustainable credits. However, the amount of production of RAP and its utilization has no comparison. The general practice is to replace a small fraction of virgin aggregates with RAP, usually restricted to a maximum of 30%, in base layers to promote RAP usage in the pavement industry. The present study focuses on the utilization of a high proportion of RAP (>50%) substitution in virgin aggregates (VA) as a base material in low volume roads (LVR). Mixes containing 100:0, 80:20, and 60:40 proportions of RAP:VA stabilized with different dosages of fly ash were evaluated for maximum dry density (MDD), optimum moisture content (OMC), unconfined compressive strength (UCS), resilient modulus (Mr) and California bearing ratio (CBR). It was observed that the 80:20 RAP:VA design mix with 40% fly ash meets the design requirements (UCS > 1.7 MPa and CBR > 80%) specified by the Ministry of Rural Development (MoRD), Government of India, and was considered to be an optimum mix. An example is discussed to design an LVR with an optimum mix according to the Indian Roads Congress (IRC) and AASHTO methods. The results revealed that the fatigue and rutting strains are well within the permissible limits for the new mix. The new mix design proved economical, as there was a 50% reduction in base layer thickness compared with the conventional design mix. [ABSTRACT FROM AUTHOR]

Depleting timber resources has generated interest in bamboo, a traditional sustainable building material of the tropics. However, dearth of strength data has been a major hindrance in its engineered application. The present paper reports experimentally verified compressive and cleavage strengths of an Indian bamboo species that is considered suitable for structural applications. The investigated compressive strength is well comparable with that of equivalent timber. The paper reports lesser strength of split bamboo specimens than round ones, which contradicts the provisions of some codes. The paper also observes that compressive strength of bamboo generally increases along its culm length, gradually from bottom to top. The paper further identifies a factor, which when multiplied by the density of a given specimen, yields corresponding permissible compressive strength. Low values of coefficients of variation and skewness of the experimental data indicate its reliability. This paper may be considered as a step towards engineered application of bamboo. [ABSTRACT FROM AUTHOR]

Coal fired thermal plants in India produce about 131 million tons of coal ash, which comprises about 25 million tons of coal bottom ash. Utilization of coal bottom ash has environmental advantages also which are of great importance in the present context of sustainability of natural resources. The replacement of river sand with industrial by-products such as coal bottom ash in concrete can prove both technically and economically beneficial to the construction industry. In this study, laboratory tests were conducted to assess the possibility of the use of coal bottom ash as a substitute material of river sand in concrete. River sand was substituted with coal bottom ash by mass in concrete at 0, 30, 50, 75 and 100% replacement level. The test results show that 28 d compressive strength and pulse velocity through concrete were not affected on the use of coal bottom ash in concrete. Water absorption and initial rate of absorption of water by capillary action increased on incorporation of coal bottom ash in concrete manufacturing. However, the secondary rate of absorption of water was constant for all concrete mixtures. Water absorption varied between 4.68 and 5.56% for all concrete mixtures at curing period of 28 d. With increasing age, bottom ash concrete mixtures showed significant reduction in permeable pore space and water absorption. Abrasion resistance was measured in terms of average depth of wear. Bottom ash concrete mixtures displayed marginally lesser resistance to abrasion than control concrete. All the concrete mixtures showed decrease in the average depth of wear with increasing age, in other words increase in resistance to abrasion. [ABSTRACT FROM AUTHOR]

In mining and civil engineering projects, physico-mechanical properties of the rock affect both the project design and the construction operation. Determination of various physico-mechanical properties of rocks is expensive and time consuming, and sometimes it is very difficult to get cores to perform direct tests to evaluate the rock mass. The purpose of this work is to investigate the relationships between the different physico-mechanical properties of the various rock types with the P-wave velocity. Measurement of P-wave velocity is relatively cheap, non-destructive and easy to carry out. In this study, representative rock mass samples of igneous, sedimentary, and metamorphic rocks were collected from the different locations of India to obtain an empirical relation between P-wave velocity and uniaxial compressive strength, tensile strength, punch shear, density, slake durability index, Young's modulus, Poisson's ratio, impact strength index and Schmidt hammer rebound number. A very strong correlation was found between the P-wave velocity and different physico-mechanical properties of various rock types with very high coefficients of determination. To check the sensitivity of the empirical equations, Students t test was also performed, which confirmed the validity of the proposed correlations. [ABSTRACT FROM AUTHOR]

The paper presents experimental studies conducted on two grades of High Performance Concrete (HPC) mixes of M70 and M80 using mineral and chemical admixtures in various proportions. The main purpose of this investigation is to develop confidence among user agencies in India to use mineral and chemical admixtures in a desirable proportion in most of the construction works. Overall, the paper highlights the usage of admixtures to achieve high strength concrete mixes, and from the experimental investigation, it is clear that mineral admixtures contribute effectively a lot not only for achieving durability, but also high strength. [ABSTRACT FROM AUTHOR]

Surface miners have proved to be one of the major mechanical excavators, particularly, in soft and medium hard rock for meeting the higher demand for minerals. Selecting proper specifications of surface miner in a given geo-excavation set up is still a challenge faced by excavation engineers. Selection and performance of surface miner is influenced by a host of intact rock/rock mass properties apart from various machine design and operating parameters. These parameters need to be identified for their successful application and operational effectiveness. Production evaluation of surface miners was done in three limestone mines and three coal mines located at various parts of India. This paper presents the influence of rock/rock mass properties, namely, uniaxial compressive strength, tensile strength, P-wave velocity, modulus of elasticity and brittleness index on normalized production potential of surface miner. Laboratory P-wave velocity, modulus of elasticity and brittleness index showed better relation with normalized production in comparison with other parameters. A multiple regression model considering these variables has been developed for production evaluation using surface miner. The model has a reasonable degree of index of determination (0.78) and can be used as a good starting point for production evaluation in new projects. [ABSTRACT FROM AUTHOR]

In this experimental investigation, a brief review is presented on high strength concrete by using mineral and chemical admixtures. We have designed high strength concrete of grade M80. We have used all the mineral admixtures, namely, fly ash, blast furnace slag, silica fume and metakaolin, contributed by various reputed industries in India. We have collected all the details of these mineral admixtures from those reputed industries, and a brief introduction of all mineral admixtures is presented in this project work. We have also used superplasticizer (chemical admixture), namely, conflo manufactured by "fosrock chemicals" in Bangalore. We have used this superplasticizer in order to achieve good workability under lower water-cement ratio for high strength concrete such as M80. We have compared the compressive strengths of all these mineral admixtures at their individual replacements and combinations of various percentages. We have also found out the percentage replacements of these mineral admixtures in order to achieve maximum strength. We have presented the results in the form of graphs. [ABSTRACT FROM AUTHOR]

Abstract: A novel hot spring bacterial strain was isolated and characterized from Bakreshwar, West Bengal, India. Phylogenetic analysis of partial 16 S-rRNA gene sequence (697 nucleotides) suggested that the isolate was affiliated with the family ‘Firmicutes’ and 99.8% homologous with Thermoanaerobactor thermohydrosulfuricus. A unique thermostable and high pH tolerant protein (28kDa) secreted by the bacterium was isolated whose N-terminal partial sequence (25 AA) suggested that the protein was similar to mammalian carbonic anhydrase-II. This bacterium or its unique protein both increase the compressive (>25%) and tensile (>20%) strengths, hardness and elastic modulus of cementitious material when incorporated to the cement/cement–sand mixture. The protein (named as bioremediase) possesses silica leaching activity, which is increased by calcium ions. No esterase and/or proteolytic activities are present in the protein. The use of such isolated bacterium or its protein in concrete technology develops new construction material that may be used for self-healing concrete in future. [Copyright &y& Elsevier]

Four rock types (quartz mica gneiss, schist, quartzite and calc-silicate) located in the Satluj and Alaknanda valleys were used to test whether a Schmidt hammer can be used to distinguish rock surfaces affected by various natural and man-induced processes like manual smoothing of rock surfaces by grindstone, surface weathering, deep weathering, fluvial polishing and blasting during road construction. Surfaces polished by fluvial process yielded the highest Schmidt hammer rebound (R-) values and the blast-affected surfaces yielded the lowest R-values for the same rock type. Variations in R-value also reflect the degree of weathering of the rock surfaces. It has been further observed that, for all the rock types, the strength of relationship between R-values for the treated surfaces (manual smoothing of rock surface by grindstone) and the unconfined compressive strength (UCS) is higher than for the fresh natural surfaces. [ABSTRACT FROM AUTHOR]

Sewage sludge (SS) management has been regarded as a serious environmental and health issue around the globe, especially in developing countries like India, mainly due to the lack of proper regulatory criteria, and appropriate engineering infrastructures. The present research work demonstrates the utilization of Fly Ash (FA) in varying percentages (with an interval of 10%) with SS as brick for sustainable building material with special emphasis on dimensional Effect. The impact of dimensional effect is measured using compressive strength behaviour for a stress rate of 14 MPa/min of two different sizes of brick i.e. D1 and D2 of sizes 7 × 7x7 cm3 and 2 × 2x2 cm3, respectively. Owing to the sintering effect, the maximum strengths of 4.02 MPa and 7.6 MPa are noticed for a composition of 60% SS+40% FA for D1 and 40% SS + 60% FA for D2, respectively. According to the Indian Standards (IS) 13757: 1993, an exhibited strength of more than 3.5 MPa by any brick composition enables it to be used as a common building brick. In general, due to the formation of triangular wedges, the D2 bricks exhibited better strength for any mixing ratio of FA and SS. The added benefit in our study was lower thermal conductivity (0.48 Wm−1K−1) of the prepared fired brick implying its better insulation property. Our study uniquely highlights the possible utilization of FA for stabilizing SS for sustainable substitution of natural clay fired brick. Future study may further investigate the compositional effect of FA on the thermal and thermodynamic attributes of the bricks. Image 1 • Pioneer study on bricks that visualizes dimensional effect along with mechanical properties. • 40–60% fly ash with sewage sludge satisfies Indian codal provisions as construction material. • Thermal conductivity of synthesized brick is lower than conventional fired clay bricks. • Dimensional effect significantly influences the compressive strength behaviour. [ABSTRACT FROM AUTHOR]

The mining of natural material such as sand on large scale for use in construction of infrastructure in developing countries like India is posing threat to the environment. To save the environment, therefore, it becomes obligatory on the part of researcher to explore the utilization of industry by-products in place of natural material. In this study utilization of saw dust generated by wood industry in concrete has been explored. This article presents properties of concrete using different percentage of water and sodium silicate treated saw dust as replacement of sand. Saw dust passing through 4.75 sieve was treated with water and sodium silicate for 24 h before using in concrete. Natural sand was replaced with 5, 10,15 and 20% water treated saw dust in concrete mixture. The effect of silica fume on properties of concrete containing 5% water treated saw dust was also studied by replacing 4, 8 and 12% cement with silica fume in concrete. It was observed that concrete made with 5% water or sodium silicate treated saw dust displayed compressive strength comparable to that of control concrete. However, for 10% replacement level, compressive strength and split tensile strength decreased by 30.30% and 32.19% respectively, at 28 days. Total charge passed, water penetration and capillary water absorption increased by 224%, 153% and 117.4%, respectively, on use of 10% treated saw dust. The concrete mixture modified with sodium silicate treated saw dust showed remarkable improvement in respect of resistance to chloride ion penetration. As expected, the results showed considerable decrease in density of concrete with the use of saw dust as replacement of sand. Addition of sodium silicate treated saw dust resulted in ettringite formation in large quantity in concrete. • Sand in concrete was replaced with 5, 10, 15 and 20% water treated saw dust. • The optimum quantity of water or sodium silicate treated saw dust is 5%. • Density of concrete decreased on use of saw dust. • Strength properties of concrete modified with 5% saw dust is comparable. • Chloride ion permeability improved on silica fume in saw dust modified concrete. [ABSTRACT FROM AUTHOR]

• Mechanical strength and pore properties are checked with over burnt brick aggregate. • Nonlinear relation is obtained among permeability, porosity and compressive strength. • For single sized aggregates, permeability lie in the range of 1.2–2.1 cm/s. • Prediction equations are made for porosity, permeability and compressive strength. In the search of alternate construction materials, over burnt brick aggregate has enrolled its appellation as a low cost sustainable alternate material. In the north-eastern part of India, especially in Tripura, the shortage of natural stone aggregate has opened up the field for over burnt brick aggregate to be used as an alternate pavement material. This study mainly focuses on the characterization of pervious concrete mixes produced with over burnt brick as coarse aggregate. Pervious concrete, in the recent era, has been considered as the emergent technology due to its prominence as an environmentally and hydrologically sustainable pavement system. In this paper, a series of test samples are produced using various design variables and then the mechanical strength and the pore properties of porous mixes are evaluated. Aggregate gradation, water-cement ratio and the percentage of fine aggregate are chosen as the design variables and their effect in the compressive strength, tensile strength, flexural strength, porosity, permeability, etc. are estimated. The statistical analysis is also carried out using the experimental test data and prediction equations are developed to estimate the porosity, permeability and the compressive strength of the pervious concrete mixes. The predicted equations fitted well and showed a very good agreement with the calculated results. These equations can be directly used for the selection of the mix proportion and the designing of pervious concrete mixes made with over burnt brick aggregate. [ABSTRACT FROM AUTHOR]