In this paper, the fresh, hardened and duraility properties self-compacting concrete (SCC) were studied with different variables. The substitution levels of ordinary Portland cement (OPC) by fly ash (FA) were kept as 0, 5, 10, 15, 20 and 25

This study presents the results of the inclusion of binary admixtures [Fly Ash (FA) + Silica Fume (SF)] and Recycled Coarse Aggregate (RCA) in Self-Compacting Concrete (SCC). First, SCC mixes were prepared by replacing parts of 43-grade Ordinary Portland Cement (OPC) with different combinations of FA + SF to find their optimum replacement level (25

The findings of an experimental programme to explore the properties of self-compacting concrete (SCC) containing dual admixtures are presented in this paper. Three different SCC mixes (grade-M25) were prepared using: (i) ordinary portland cement (OPC) and natural fine aggregate (NFA) (M-1); (ii) OPC, dual admixtures [fly ash (FA) + Metakaolin (MK)] and NFA (M-2); (iii) OPC, dual admixtures, NFA and manufactured sand (M-sand) (M-3). The properties of the various mixes are compared in both fresh and hardened states. The optimal level of OPC substitution by binary admixtures is 25

The main components of concrete are cement and river sand (R-sand). Due to excessive production of cement, CO2 emission also increases which causes air pollution. On using R-Sand, large scale depletion of natural sources creates environmental problems. In view of the increasing national and global consensus on the environmental protection, the governments have put restrictions on mining of R-Sand from the river beds. To overcome these problems, there is a need of cost effective alternatives materials so as to make the construction sustainable without compromising its quality. In the production of Self Compacting Concrete (SCC), fly ash (FA) is utilized as an additional cementitious ingredient, which improves its performance. It solves the problem of FA disposal and environmental pollution too. The manufactured sand (M-sand) is also an alternative material which may solve the problem of shortage of R-Sand, if found suitable. In this study, M-Sand and FA were incorporated in the preparation of a sustainable SCC. After optimisation of FA and M-sand doses in the final mix, two types of SCC mixtures were developed: M-1, which consisted of 100% OPC + 100% R-Sand, and M-2, which consisted of 80% OPC + 20% FA + 50% RSand + 50% M-sand. Fresh properties of all SCCs were determined as per EFNARC/BIS recommendations. For destructive testing standard size specimens were cast to determine desired strengths after curing in tap water for 90 days. Rebound Hammer (RH) and Ultrasonic Pulse Velocity (UPV) were utilised in NonDestructive Testing (NDT) to determine the strength, homogeneity, and integrity of both SCCs. Further, the water absorption of the specimen was measured up to 90 days. XRD analysis was also performed. Copyright (c) 2022 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on Novel Engineering Materials for Biomedical, Energy, Environment, Sensing, And Other Applications

The behaviour of curved box-girder bridge is quite different from the straight one as it is experienced by the additional torsional moments. The analysis and design of such box-girder bridges are quite complicated when the curve angle is varied. The effect of curve angle on the forces and deflection in the girders, inner and outer, of a simply supported single cell reinforced concrete curved box-girder bridge is investigated in this study. A Finite element based software, CSiBridge v.20, was used for the analysis. A convergence study was performed on the proposed model to select the optimum mesh size and the results obtained are validated with the published literature. The variation of absolute values of forces and deflection along both the girders, under dead load (DL) and IRC (Indian Road Congress) live load (LL), is observed and the equations are proposed for their prediction in terms of non-dimensional parameters, using the statistical approach. The present results may be helpful to the designers in the analysis and design of curved single cell reinforced concrete box-girder bridges.

SUMMARY The box-girder bridge has become very popular lately due to its serviceability, stability, and structural efficiency. The study of such a bridge requires analytical, experimental, or numerical methods. The structural behavior of the box-girder bridge is very complex and is quite cumbersome to be investigated by conventional methods. This paper presents a modelling process for the analysis of simply supported reinforced concrete (RC) box-girder bridges (straight, skew, curve, and skew-curved) using the finite element method under Indian loading conditions. This modelling process is developed on the basis of the Codal provisions of Indian Road Congress (IRC) 6:2017 and IRC 21:2000, and its implementation is quite simple as it avoids the cumbersome calculations and requires less time. Different values of the span, span-depth ratio, and the number of cells are considered to suit the requirements, and limiting criteria for stresses and deflection are checked. The static and free vibration analyses are carried out, and the results are compared to control the applicability of the proposed modelling process. The present modelling process is applied to analyse the RC box-girder bridges up to 50 m spans, and no erection procedure is included. However, one may follow the proposed modelling procedure for any box-girder bridge for its analysis.

By addition of some pozzolanic materials, the various properties of concrerte viz, workability, durability, strength, resistance to cracks and permeability can be improved. Silica fume is one such pozzolanic material. Silica fume is a by product obtained from the reduction of high – purity quartz with coal or coke and wood chips in an electric arc furnace during the production of silicon metal or silicon alloys. The use of Silica fume as admixture in concrete has opened up one more chapter on the advancement in concrete technology. More sticky mix can be obtained by addition of Silica fume in concrete. Using Silica fume in concrete increases its compressive, tensile, flexural and impact strengths and decreases permeability and bleeding. In this paper, an attempt is made to describe the suitability of silica fume in concrete.

Self-Compacting Concrete (SCC) is often made with natural aggregates and a portion of single or binary admixtures in place of Ordinary Portland Cement (OPC). The use of Recycled Coarse Aggregates (RCA) derived from demolition and rubble wastes may also be beneficial and may provide a number of benefits, including maintaining ecological balance, providing cost-effective constructions, lowering CO2 emissions, reducing excessive resource consumption, and producing concrete for sustainable development. In order to partially replace the OPC and Natural Coarse Aggregates (NCA) for the production of M−30 grade SCC, the current work explores and uses a combination of mineral admixtures viz., Fly Ash (FA) + Silica Fume (SF), and RCA, respectively. The effect of inclusion of these admixtures in both separately (FA and SF) and combination (FA + SF) with and without RCA content on the fresh properties, compressive strength and microstructure characteristics (XRD and SEM) of all the SCC mixtures for the durations of 28, 120, 270 and 540 days, are evaluated. It is concluded that the compressive strength of different SCCs rises in the range of 1.26–19.10 % when using different type of admixture(s) or their combination, but the strength of various SCCs decreases in the range of 2.14–5.08 %, when using RCA content in the SCC mixtures. Also, concrete containing either FA, SF or FA + SF content are beneficially used in the SCCs but the mechanical characteristics of SCC mixtures are negatively impacted by RCA content.

In the present study, M-30 grade Self Compacting Concrete (SCC) was designed using natural fine and coarse aggregates, Ordinary Portland Cement (OPC) and varying percentages of binary admixtures i.e., Fly Ash (FA) and Silica Fume (SF) for part replacement of OPC. Also, the effects of these admixtures in combination (FA + SF) were evaluated on the fresh properties, compressive strength, flexural strength, split tensile strength, cost and CO2 emission. Further, the micro-structural analyses (XRD and SEM) of dif-ferent samples were carried out. The strength of different SCCs increases in the range of 4.34-44.88 % depending upon the type of admixture(s) or their combination and number of days. The cost of SCC reduces in the range of 2.77- 10.97 %, when OPC is replaced in part by different admixtures or their combination. The reduction of CO2 emission lies in the range of 8.84-22.10 %, when OPC is replaced by admixture. Thus, the results show that the concrete containing either FA or binary admixtures are not only stronger and economical but also helpful in the environmental protection. Copyright (c) 2022 Elsevier Ltd. All rights reserved.

The data on number of fruit flies trapped per week for a period of 7 weeks were taken at cucumber field var., Pusa Sanyog. It can be inferred from the data that irrespective of container, the mean number of trapped fruit flies was found to be significantly more in lure stored for 10 days (259.25 flies/trap/7 weeks) and was at par those stored for 15 days (184.75 flies/trap/7 weeks). Overall mean numbers of fruit flies trapped at other storage periods were found at par. The trap catch of males in parapheromone traps is affected by a large number of factors including the abiotic factors of the environment which indirectly alter the target insect i.e., fruit fly and behavior of the target pest. The maximum trap catch at 10 days storage period could be ascribed due to peak activity of the pest during this period. The critical examination of data indicated a consistent trapping between 127.5–142.5 flies/trap/7 weeks at 5, 20, 25 and 30 days storage period. Efficacy on different insecticide revealed that wooden pheromones lures containing spinosad as insecticide resulted in attracting maximum fruit fly population (88.65 flies/trap/weeks) followed by malathion (28.32 flies/trap/weeks) and Lambdacyhalothrin (8.67 flies/trap/weeks).

This study presents the effect of the skew angle on a simply supported box girder bridge. CSiBridge v.20 software is used for the analysis which is based on the finite element method. The mesh size is selected from the convergence study. The variation of absolute bending moment, shear force and vertical deflection due to dead load and live load for both girders is evaluated. The bridge having skew angles up to 20° can be analysed and designed as a straight one. The equations for bending moment ratio, shear force ratio and vertical deflection ratio are deduced so that the forces and deflection of skew box girder bridges can be determined directly from the straight one. This study's results may be useful to the designer for a preliminary analysis of skew bridges.

Concrete plays a key role in every construction and a large amount of concrete is used widely. Natural river sand is one of the main ingredients of the concrete but is becoming expensive for various reasons. Also, the concern for environment is making the sand quarrying more and more difficult. Thus, there is a need of a cost-effective alternative and that is available in the form of manufactured sand (M-sand). In this experimental study, M-sand and fly ash (FA) were used for partial replacement of fine aggregate and ordinary Portland cement (OPC), respectively, in preparation of self-compacting concrete (SCC). After optimizing the dose of M-sand and FA in the final mix, 100 mm cubes were cast to investigate the following: loss in compressive strength and visual changes. The cubes of SCC with and without replacement of fine aggregate and OPC were cured separately, in 4% solutions of nitric acid (HNO3), sulphuric acid (H2SO4) and ammonium sulphate [(NH4)2SO4] for 12 weeks, after 28 days curing in tap water to investigate the durability of different mixes. XRD analysis of the concrete samples was carried out to study the microstructural changes. The SCC made of M-sand and FA shows better performance in different aggressive environments.

Self-compacting concrete (SCC) is a highly flowable concrete which has more binder content as compared to normal concrete and there is no need of vibration for the compaction. The use of waste materials for part replacement of ordinary Portland cement (OPC) in SCC can enhance its mechanical properties. Fly ash (FA) is the most widely used pozzolanic material for making SCC. Its inclusion in concrete improves both the workability and strength of SCC. At the early ages, the SCC made using FA shows lower compressive strength in comparison to the SCC made using OPC only; however, it gives higher strength later on. In this experimental study, workability and strength properties of M30 grade SCC were studied with variables. The replacement levels of OPC by FA were varied: 5, 10, 15, 20 and 25%. Fresh concrete properties were measured by L-box slump flow, V-funnel flow time, U-box and J-ring tests. Other (mechanical) properties were determined in terms of compressive strength (CS), split tensile strength (STS) and flexural strength (FS). The X-ray diffraction (XRD) and scanning electron microscope (SEM) analyses were also carried out to study the micro-level changes in SCC.

In this paper, the experimental results of both Normal Concrete (NC) and Self-Compacting Concrete (SCC) are presented. Both the fresh and hardened properties were investigated. The SCC was developed by replacing 20% of Ordinary Portland Cement (OPC) by Fly ash (FA), so that the amount OPC is almost same in both NC and SCC. The workability of the mix increases with the inclusion of FA and the mix becomes cost-effective. For workability, the slump test was conducted on NC while for SCC, slump flow, T50 time, V-funnel, L-box, U-box and J-ring tests were conducted. The water/binder (w/b) ratio was kept constant for both the NC and SCC. For M25 grade concrete, cubes of size 100 mm, cylinders of size 100 mm × 200 mm and beams of size 100 mm × 100 mm × 500 mm were cast to find the compressive, split tensile and flexural strengths, respectively. The samples were tested after curing in tap water for 7, 28, 56 and 90 days. The water absorption of both NC and SCC was also studied up to 90 days. The XRD analysis of both the concrete samples was also carried out to investigate the microstructural changes.

Concrete is globally used construction material and nowadays its durability is the main concern. Acid is one of the chemicals influencing the durability of concrete. Nitric acid (HNO3) is one such acid. Several mineral admixtures are used to improve the durability of concrete. Rice Husk Ash (RHA) is one of such admixtures. This paper make known the results of an experimental programme intended to explore the durability aspects of Normal Concrete (NC) and Steel fiber Rice Husk Ash Concrete (SFRHAC). M25 grade of concrete using normal constituents was designed and used for referral. The RHA was used for partial replacement of Ordinary Portland Cement (OPC). The different replacement levels considered were 10, 15, 20 and 25%. It is found that workability of concrete decreased with increase in the replacement level. The optimum replacement level was found to be 15%, with respect to the compressive strength. The hooked steel fiber was added (by volume) to the RHA and Steel fiber concrete. The cubes of both NC and SFRHAC were cured in Tap water as well as in 5% Nitric acid solution till 90 days. Nitric acid is based on acid rain, sewage and industrial waste etc. The compressive strength of cubes was determined after 7, 28, 56, and 90 days. The compressive strength of water cured SFRHAC is higher than the NC. The compressive strength of both NC and SFRHAC was found to decrease in acidic solution for all the exposure periods; however, the decrease was lower in case of SFRHAC. The XRD analysis was carried out to estimate the effect of nitric acid on the constituents of concrete. The higher peaks of Calcium Silicate Hydrate (C-S-H) are detected in SFRHAC samples. (c) 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the First International conference on Advanced Lightweight Materials and Structures.

The findings of a study on Self Compacting Concrete (SCC), made using natural and manufactured sand (M-sand) are presented. The referral SCC (M25) was made by substituting a part (20%) of Ordinary Portland Cement (OPC) with Class-F Fly Ash (FA). The other SCCs were made by replacing parts of natural sand (NS) with M-sand, by mass. The workability parameters of SCCs in fresh state were determined as per the recommendations EFNARC-2005. The specimen of both SCCs were cast and tested for important strength parameters at different ages as per Indian standards. It is found that 50% of NS can be replaced by M-sand. The specimen's water absorption was also studied up to 90 days.

Aim : Laboratory studies were conducted to study the potential of entomopathogenic nematodes and their interaction with the commonly used insecticides viz., clothianidin, imidacloprid and chlorpyriphos against first, second and third instar grubs of H. longipennis and B. coriacea. Methodology : Two entomopathogenic nematodes viz., Heterorhabditis indica Poinar and Steinernema caprocapsae Weiser were tested against I-III instar grubs of Brahmina coriacea (Hope) and Holotrichia longipennis (Blanchard) under laboratory conditions @1600IJs per cup by soil application. The mortality data was recorded after every 24 hrs up to 5 days. For evaluating the interaction effects among different tested biocontrol agents with insecticides, each entomopathogenic nematode species and insecticides was tested alone and in combination. H. indica and S. carpocapsae were applied @ 400IJs per cup. Insecticides were applied at a lower concentrations viz. 150, 100 and 75 ppm for chlorpyriphos, imidacloprid and clothianidin, respectively and were applied on the same day of nematode application with a gap of 2 hrs. Mortality data was taken after 24 hrs. Results : Individual application of H. indica and S. carpocapsae @1600 IJs per cup had clearly lethal effect and produced mortality to the tune of 55.5-90.7 % in both the species of white grubs. H. indica revealed higher virulence as compared to S. carpocapsae against both the species. Combination of both the species with all the tested insecticides yielded synergistic interactions and H. indica+ imidacloprid combination proved to be the most promising among all the tested combinations. Interpretation: Tested entomopathogens and insecticide combination produced synergistic interactions more effectively to first, second and early third instar grubs (H. longipennis and B. coriacea).

Cucurbitacae family is very important vegetable crops in the world including India. Among all the cucurbits, cucumbers are extensively cultivated in India for its wide culinary. The production of cucumber is threatened by the fruit fly. In Himachal Pradesh, India there were eight very important Bactrocera spp. was reported trapping with methyl eugenol for male. So in order to manage this fruit fly many have utilizes different method. For managing male adult of fruit fly, mass trapping using pheromone trap is widely used however, for female insecticide were applied. The side effects of utilizing insecticide have been reported by different parts of the world. So bait application technique (BAT) have been started to trap both male and female fruit fly. In this regard locally available raw material use as a bait food was evaluated in laboratory against Bactrocera tau attacking cucumber. B. tau was raised in the laboratory with collected infested fruits of cucumber at room temperature in specially designed rearing cages (38×38×45cm3). A polythene sheet was fitted over the base of the cage and filled with mixture of sterile fine sand and saw dust up to 5 cm height for pupation. The adults were provided with their natural host as well as a mixture of dry glucose and protein hydrolyzate (Protinex® Dumex Sciences, New Delhi) in the ratio of 1:1 in a Petri plate which was replaced at weekly intervals. Flies were also provided with water soaked cotton swab in a 50 ml beaker. To prevent access of predatory ants to the cages, these were placed in water filled plastic plates in which water was changed daily. For this, 25 males adult as well as 25 females adult B. tau were released together along with different concentrations food baits solution. For 15 minutes, fruit flies visiting on each concentration were recorded under no choice and multiple choice tests. The report revealed that highest attractancy was recorded in hydrolysed protein (46.00 and 46.50 per cent for male and female, respectively), followed by molasses (41.11 and 36.50 per cent, for male and female respectively). Evaluation of bait-insecticide which exposure to B. tau under laboratory conditions revealed that maximum mortality recorded in molasses + dichlorovos (97.50 per cent) followed by 96.50 per cent mortality in banana pulp + dichlorvos and 96.00 per cent mortality in hydrolysed protein + dichlorvos. Diclorvos can be replaced by more environment friendly toxicant spinosad with 24 per cent mortality in hydrolysed protein followed by molasses 22 per cent.

Self Compacting Concrete (SCC) is gaining popularity in construction industry due to several advantages offered by it. In this study, M-30 grade referral SCC was designed using the natural aggregates, Ordinary Portland Cement (OPC), and varying levels of Fly Ash (FA) for part replacement of OPC. The properties of fresh and compressive strength of hardened SCC made using above ingredients, and FA and Recycled Coarse Aggregates (RCA) for part replacement of Natural Coarse Aggregate (NCA) were also evaluated. For the first part of study, the OPC was partially replaced (0-35% by weight, at an interval of 5%) by FA, and the optimum replacement level (25%) was found for referral concrete containing NCA. For the second part of study, 12 different SCC mixes were prepared at optimum level of FA content (25%), and by replacing part of NCA (0-100% by weight, at an interval of 25%) with RCA to obtain its optimum replacement level. The workability properties of SCC and Compressive strength (CS) of hardened SCC at different FA and FA + RCA content were determined. Also, the microstructures of the optimum SCC mixes containing FA and FA + RCA were analyzed using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM).