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An experimental study was conducted to investigate the effectiveness of transverse reinforcing bars of self-compacting concrete mix (PSCC) and hybrid glass fiber reinforced self-compacting concrete mix (HFRSCC) grade M 40 under monotonically increasing axial compression. was performed for cylinders enclosed in . The behavior of SCC cylinders surrounded by a circular ring and having different volume ratios and clearances was compared under axial compression. In this work, we present a mathematical model developed to predict the stress-strain behavior of SCC and FRSCC under constrained and unconstrained conditions and validate the model using experimental results. To develop SCC, Nan Su blending method based on filling rate 1.12 and 1.14, S/A ratio 0.50 and 0.57 is applied. The steel and glass fiber usage in the hybrid fiber reinforced SCC mixture is assumed to be 1% and 0.05% of the concrete volume respectively. M 40 grade plain self-compacting concrete mixes (PSCC) and hybrid glass/steel fiber reinforced self-compacting concrete mixes (HFRSCC) constrained to different volume ratios, stresses, strains, elastic moduli, plasticity ratios, ductility ratios, and unlimited strength ratios ) has been evaluated experimentally. The following conclusions can be drawn from the stress-strain diagram: 1) Maximum load-bearing capacity and strain at peak stress are higher for his HFRSCC than for PSCC. 2) The presence of steel and fiberglass increases the strength bearing capacity and allows it to withstand greater loads at peak loads. 3) If the containment is in the form of a lateral ring boundary, the effect of fibers is almost negligible. This clearly shows that HFRSCC has a stronger containment effect compared to his PSCC. The strength confinement factor is lower for HFRSCC, suggesting that HFRSCC offers a superior confinement factor compared with his PSCC.

Ferrock is the commercial name given by the Dr Stone working with university of Arizona which holds the patent on this novel material. This is an alternative material developed for structural applications in place of concrete. In this paper, ferrock mortar is prepared with various solids such as iron powder, iron dust, cement and fly ash to establish the optimum combinations of solids for preparing the high strength ferrock systems. Iron dust in the form of powder (size less than 90 microns) and fine aggregate (size between 150 microns to 2.36mm) is used in the study to develop the iron carbonate matrix which is major binding material in ferrock. For the process of iron carbonation, carbon dioxide is prepared from the chemical reaction of sodium bicarbonate and acetic acid. Iron dust cubes are carbonated to form iron carbonation matrix upon fusion. This material has very high strength than the references cement mortar samples.

Pile foundations are used to support both vertical and horizontal loads in many geotechnical projects, such as coastal and offshore engineering. In this project, the Finite Difference Method is proposed to solve the differential equation governing the lateral and axial pile response. Initially, the behaviour of the pile subjected to lateral load will be analysed. The effect of various parameters like pile head fixity, the cohesion of surrounding soil, pile diameter, and length of the pile on lateral pile response will be analysed. Finally with these conditions, the deflections profile of the pile subjected to both lateral and axial load is investigated. By using python code we can easily find out the increase in diameter of pile, cohesion of surrounding soil effect on pile head and effect of increase in combined load will be studied. The above stated parameters will be studied for combined loading also under the free and fixed head conditions.

The paper states the advantages of web-based Primavera P6 for structural planning and scheduling Bridge building framing the problems and difficulties experienced in the construction schedule and resource availability. Only Bridge Design and Plannings taken for the project consideration. After the detail creation of Bill of Quantities of the proposed bridge. Here the Bridge consists of four spans only. Each Span is of 10.4 m length. Bridge is located at Yellareddy Tank Bund Portion, Nizamabad district (Hyderabad-Medak-Bodhan). The Resource Planning is the creation of Organization Breakdown Schedule (OBS) and Enterprise Project Structure (EPS) of the project and also to create Work Breakdown Schedule (WBS) and to insert the corresponding activities and schedule them on the basis of created calendar and need to level/smoothen the resources and make effective use of them. Organization Breakdown Schedule (OBS) and Enterprise Project Structure (EPS) of the project has been created Work Breakdown Schedule (WBS) and the corresponding activities are created and need to schedule their resources to activities on the basis of created calendar and need to level/smoothen the resources. Resource Scheduling involves the Scheduling of Project and Activity Network Diagram. Resource allocation enables you to allocate equipment, labor, and material expenditures to your timetable. The reports in Primavera P6 may be used to track resource allocation and potential over-allocation of labor resources.

In this paper, it is proposed to study the static flexural performance of hybrid (glass and steel) fiber reinforced M30 grade self-compacting concrete (SCC) beams made with glass fiber reinforcement polymer (GFRP) re-bars. Nan Su mix design approach is adopted to develop the M30 grade plain SCC (PSCC) mixes. Glass fibre SCC (GFRSCC), steel fibre SCC (GFRSCC) and hybrid fibre SCC (HFRSCC) mixes are prepared using the optimum dosages of glass (0.05%) and steel fibres (1%) by volume fraction. HFRSCC reinforced beams of size 1200 *200*150 mm will be casted with steel and GFRB rebars and tested to study the flexural properties such as ultimate flexural strength, load at first crack, deflection at the center, crack width and crack patterns. For the above fibred beams, load-deflection relations will be established. The HFRSCC beam made with GFRP rebars have the load carrying capacity 37.03% more than HFRSCC beam made with steel rebars. The deflection for the HFRSCC beam made with GFRP rebars is 61.52% more than beam made with steel rebar HFRSCC beam made with GFRP rebars increases the load at first crack, ultimate flexural strength, and deflection at the centre at failure and the crack width for same HFRSCC beam made with steel rebars

Concrete’s thermal properties are more complex than for most materials because not only is the concrete a composite material whose constituents have different properties, but its properties also depend on moisture and porosity. Exposure of concrete to elevated temperature affects its mechanical and physical properties. In the current study, M40 and M80 grades of plain self-compacting concrete (SCC) mixes are developed using Nan Su mix design principles to investigate the effect of elevated temperatures on 1) weight and compressive strength 2) compressive strength of SCC when tested cool and hot 3) effect of 2, 4 and 6 hrs. exposure duration of elevated temperatures on compressive strength 4) modulus of elasticity 5) size of testing specimen and 5) effect of thermal cycles on SCC mixes. Results derived the following conclusions 1) the M80 specimens lose more strength than M40 SCC specimens when subjected to elevated temperatures ;2) specimens heated and then permitted to cool before testing lose more strength than those tested while hot; 3) the longer the duration of heating before testing, the larger the loss in strength; 4) The decrease in modulus of elasticity caused by elevated-temperature exposure is more pronounced than the decrease in compressive strength. 5) Small test specimens generally incur greater strength losses than larger ones and 6) Specimens subjected to several cycles of heating and cooling lose more strength than those not subjected to thermal cycling.

In the current study, effect of particle size of colloidal nano-silica on the properties of the SCM based concrete is studied. The nano-silica particle sizes adopted for the study are 30nm, 60nm and 90 nm. The M20 grade concrete system is made up of cement (C), fly ash (FA), micro-silica (mS) and nano-silica (nS). Compressive strength test at 60 days and pore structure analysis are carried out for C-FA-mS-nS system. The hydration of Portland cement is significantly influenced by the colloidal nanosilica (CNS) particle size. High doses of nS content boost the pozzolanic reaction and the creation of CSH and CASH gels, but they also have a negative impact on the strength development of the material by increasing microcracking due to the self-desiccation effect. The addition of nanosilica to concrete can significantly enhance its qualities after hardening because it ensures the pozzolanic reaction, the seeding effect, which both increase the degree of hydration, and the filling effect, which can fill the internal porosity defects. The cement-mS system's impermeability was greatly improved by the nS because it improved the microstructure, increased the complexity of the pore structure, and refined the pore structure.

This document provides design principles for concrete beams reinforced with glass fiber reinforced polymer (GFRP) bars per the ACI 440.1R-15 regulation. One of the main advantages of using glass fiber reinforced polymer rods instead of traditional steel reinforced rods is their lighter weight and higher corrosion resistance. However, the bending failure mode of FRP reinforced concrete (FRP-RC) beams is brittle rather than ductile because the elasticity of fiber reinforced polymer (FRP) bars is linear until failure and the elongation at break is small. For FRP-RC elements, concrete crushing compression failure, which gives various warnings before failure, is the preferred failure mode. In other words, unlike the usual design practice for reinforced concrete (steel-RC) beams, for FRP-RC beams, an over-reinforced structure is preferable to an under-reinforced structure. In addition, since the FRP RC member has low rigidity of the FRP rod, it bends more and cracks larger than the steel RC member. These factors limit the field of application of FRP. Here is a design example of a rectangular beam with tension reinforcement according to ACI regulations.

For the purpose of minimising and managing project delays, effective planning and scheduling are essential elements of construction projects. Globalisation has led to an increase in the scale and complexity of construction projects. With the help of project management software, the quantity of paperwork and time required for such initiatives can be reduced. A warning system must be accessible throughout the project to alert the organisation to potential achievements and failures. Today's market offers a variety of computer software applications for project management, including MSP, Primavera P6, and others. Primavera has made it simple to assess the real progress of a construction project to the expected pace of the task. The project management tool Primavera P6 gathers, documents, monitors, regulates, and publishes data on project performance. Planning, allocating, and scheduling resources for a G+4 residential development are all part of this project. This study highlights the value of scheduling and interferes with the software by working on a construction project for a commercial building. This paper effectively demonstrates all the crucial steps, such as generating an EPS, developing a WBS, connecting tasks in accordance with their dependency and resource availability, and determining the Critical Path.

In the present study, the stress-stain behaviour of confined concrete made with nano-silica (nano-SiO2) were taken up. The stress-strain behaviour was studied for the M30 and M50 grades nano-silica (nano-SiO2) concrete mixes confined with steel rebars. The confinement was given in the form of steel hoops in the cylinders, 3 hoops (0.8%), 4 hoops (1.1%), 5 hoops (1.3%) and 6 hoops (1.6%). The addition of nano-silica (nano-SiO2) along with confinement of concrete with steel hoops enhanced the compressive strength, indicating further confinement effect in the concrete. It is observed that the addition of nano-silica (nano-SiO2) is helpful in lower confinements only. Beyond 1.1% confinement, doesn’t show any effect on compressive strengths. From the stress-strain behaviour of all types of concrete mixes, it is concluded that the ultimate load-carrying capacity and strains at peak stresses are more in nano-silica (nano-SiO2) concrete with steel hoops for mixes up to 1.1% confinement. The addition of nano-silica (nano-SiO2) to concrete has increased the ductility in both confined and unconfined states

In the present work, assessment of corrosion resistance for M30 grade concrete made with basalt fibres in terms of Resistivity, Potentials and Chloride ion diffusion is made to understand the corrosion resistance studies of concrete specimen made with basalt fibre and BFRP bars. The time of total charge passing till full crack failure for different effective covers considered is more for M30 grade concrete beams made with basalt fibres and BFRP rebars. The time of total charge passing at failure in M30 grade concrete beams made with basalt fibres and BFRP rebars is more because beam specimens did not develop any fissures or micro cracks. Measured electrical resistivity values of M30 grade concrete beams made with basalt fibres have shown high electrical resistance indicating their superior corrosion inhibition ability. M30 grade concrete beams made with basalt fibres and BFRP rebars used for the study exhibited very less probability (less than 5% probability) for corrosion at 28 days.

Very limited guidelines are available on the use of corrosion resistant inhibitors as a constituent material in concrete due to availability of statistics on its corrosion inhibiting efficiency. So the study is conducted on the M25 grade concrete mixed with few selected corrosion inhibitors of organic and non-organic nature to comprehend the impact of these corrosion inhibitors on the conductivity of electricity in these concretes. Based on the other researchers’ work, four well know corrosion inhibitors such as Calcium nitrate, Di-ethanolamine, Sodium nitrite and Hexamine and are chosen for study. Dosages of 1%, 2%, 3%, 4% and 5% the weight of cement are chosen. Measured electrical resistivity and half-cell potential values of all corrosion inhibitors admixed M25 grade concrete mixes indicates the superior corrosion inhibition ability of calcium nitrate and Di-ethanolamine’s with shows high electrical resistance.

In this paper, a mathematical model for predicting the stress –strain and moment curvature relations in concrete is developed. A good number of empirical equations were proposed to represent stress-strain behaviour of conventional concrete. Most of the equations can be used for the ascending portion of the curve only. In 1997 Mansur et al. have adopted Carriera and Chu (1985) model, which was based on the model proposed by Popovics (1973). As such, model proposed by Mansur et al includes both ascending and descending portions of the stress-strain curve for the confined concrete with introduction of two constants for the descending portion of the curve. Several researchers proposed various empirical equations for stress-strain behaviour as briefly reported in the previous chapter. An attempt has been made in this study to develop mathematical models for concrete in unconfined state. These analytical equations can be applied to any concrete with slight modifications. These models are developed to validate the experimental values obtained.

In this paper, the study of the influence of nano-silica (nano-SiO2) on the properties of the interface between CSH gel and cement particles and its effect on nano-mechanical properties of the products at the interface zone was examined. In this paper M50 grade SCC mixes were developed using 5% micro-silica and various percentages of 0.5%, 1.0% and 1.5% nano-SiO2. For 1.0% nano-SiO2 addition to M50 grade SCC mix, the compressive strength is maximum. Similarly concrete quality using non-destructive techniques, water absorbtion capacity and porosity are also assessed.

SCC is expensive when compared with normal conventional concrete. Hence, it is desired to produce low cost SCC by replacing cement with higher percentages of fly ash, which is a no cost material and available in abundance. At the same time to achieve higher grade HVFASCC, micro silica which is otherwise condensed silica fume can also be used along with fly ash to enhance the strength properties of HVFASCC. By replacing fly ash in high volumes in the mix, high amount of pozzolanic material becomes available, majorly reactive silica, for which more calcium hydroxide is necessary for further pozzolanic reaction. As we are reducing cement quantity, the amount of calcium hydroxide available is reduced thus demanding external addition of hydrated lime which can be supplied as additive to cater to the need of calcium hydroxide required for reactive silica in fly ash.The present investigation aims to achieve strength for high volume fly ash self-compacting concrete. The replacement of cement with fly ash is made in 45%, 50%, 55%, 60%, 65% and 70% with 20% hydrated lime and 10% silica fume in one trial. In another trial, 30% hydrated lime and 10% silica fume is added with replacement of fly ash to cement varying in same percentages. The design mix is tested for workability and flowability and cubes are casted for compression strength test and tested at 28 day,, 56 day, and 90 day,.

The study present in this paper reveals the corrosion inhibiting efficiency of M25 grade concrete induced with Sporosarcina pasteurii bacteria. The accelerated corrosion induced crack method is applied on reinforced bacterial concrete which is the modified philosophy of constant voltage technique. In the current investigation, for different cover thicknesses considered, total time required for charge passed until full longitudinal crack occurs along the cover thickness due to corrosion of steel reinforcement in concrete specimens are measured using which Charge Deterioration Factors (ChDFs) are evaluated for bacterial reinforced concrete beams made with various cell concentrations of Sporosarcina pasteurii bacteria. It was established that beams made with cell concentration of 105 cells/ml of mixing water offers superior corrosion inhibition ability as time taken to form full length longitudinal crack is more than in other beams made with 103 cells/ml, 104 cells/ml and 106 cells/ml cell concentration of bacteria chosen for the study.

The presented work reveals the strength properties of M70 grade high performance basalt fibre reinforced concrete (BFRCC) containing 0.2%, 0.3% and 0.4% basalt fibre content by volume of concrete. 10% Silica fume is admixed for attaining higher strengths as preferred. Compressive, split-tensile and flexural strengths are evaluated. The BFRCC microstructure is found to be improved due to enrichment of interfacial transition zone with chopped basalt fibres. It was found that different fibre lengths require different dosages to yield maximum effect on the properties of concrete. Stress- strain responses of M70 grade BFRSCC yields improved ultimate strain and strain at peak load indicating its energy dissipation capacity at fracture.

This paper prophesies the stress strain behaviour of M30 grade concrete reinforced with basalt fibres of length 12 mm, 36 mm and 50 mm of amounts 0.4%, 0.4% and 0.3% by volume of concrete respectively. Modulus of elasticity and toughness of M30 grade basalt fibre reinforced concretes are also evaluated. It was found that BFRCC mixes show good resistance to impact and has superior dissipation capacity. The optimal basalt fibre volume fraction is 0.3% and length is 50 mm. For this case, toughness index and energy absorbed at fracture have considerably enhanced. With the volume fraction of basalt fiber exceeding the optimum volume fraction, the mechanical properties of basalt fiber are weakened.

This paper presents the chloride ion penetration and diffusion capability of ternary blended concrete made with various water cement ratios. Ternary blended concrete is made with various combinations of microsilica (MS) and fly ash (FA) for water-binder ratio of 0.55, 0.45 and 0.35. A total of five combinations such as 5% micro-silica + 15% fly ash, 5% micro-silica + 20% fly ash, 10% micro-silica + 15% fly ash , 10% micro-silica + 20% fly ash and 0% micro-silica + 0% fly ash by weight of cement were studied for compressive strength, chloride ion permeability and pore structure analysis. It was found that 5% micro-silica + 15% fly ash showed better performance due to due to well-developed pore structure and microstructure.

This paper presents the mechanism and chemistry behind the geo-polymerization and its application in development of Geo-polymer concrete. In this paper, guidelines to develop a geo-polymer concrete is discussed along with the factors affecting the geopolymerization process in concrete. It is concluded that curing temperature, ratio of alkaline liquids , chemical ratio of silicate and sodium in sodium silicate, alkaline liquids / Si-Al source materials ratio, sodium silicate/ hydroxyl ions ratio, presence of calcium, presence of excess water and Si/Al ratio in source materials have significant effect on the development of geopolymer concrete and its performance.

Pure Mysore and two bivoltine breeds NB4D2 and CSR2 were reared at 25°C, 30°C and 35°C and 75-80 RH% from a day before 4th moult till spinning. Larval weight, larval duration, silk gland weight, silk gland - somatic index, silk conversion index, silk productivity, ERR, rate of cocooning, cocoon yield, cocoon weight, shell weight, shell percentage, filament length and fecundity were significantly reduced at 35°C than at 30°C. The economic characters were affected more in bivoltine races than in PM, and in CSR2 than in NB4D2 in the two bivoltine races. Expression of economic characters, when late age worms were held at high temperature, has a functional value in the selection of high temperature tolerant breeds. The physiological basis of temperature compensation in the expression of economic traits in races having different limits of high temperature tolerance is examined. The severity of impairment of economic traits, and the time and the number of larvae and pupae died have a strong racial bias. [ABSTRACT FROM AUTHOR]