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The paper focuses on the construction methodology, design and analysis of cut and cover tunnel sections of the Bilaspur-Bhanupali-Beri broad gauge line by Rail Vikas Nigam Limited (RVNL) in Himachal Pradesh. The design was carried out during the industrial internship at Altinok Consulting Engineering Pvt. Ltd, New Delhi, India. The survey team developed the plan and profile of the alignment. Referring to the alignment, different L-sections were developed to identify the location of cut and cover section. To gain a clear understanding of the structural behavior and reinforcement needs, beam model and plate model of cut and cover section were created using STAAD Pro, and a comparative study of the forces between 2D and 3D models of cut and cover sections was done. The results indicate that the 2D model tends to be more conservative compared to the 3D model, which has been discussed. [ABSTRACT FROM AUTHOR]

The paper examines the seismic response of bridge piers, highlighting the essential role of soil-structure interaction (SSI) in enhancing structural resilience. Utilizing MIDAS and LPile software, the study evaluates SSI's impact on bridge pier performance during seismic events. The study involves modeling and analysis under varying soil conditions using MIDAS software. LPile software calculates soil spring stiffness, enabling realistic SSI simulations in MIDAS models. The key objectives include comparison of bridge on deep foundation by analyzing soil properties' effects on SSI, comparing fixed base and SSI models, and providing practical design insights. The findings show significant differences in seismic performance with SSI. The fundamental period increased by 28%, indicating a more flexible response. Maximum displacements in the bridge deck rose by 25% in both X and Y directions, compared to a fixed base model. Additionally, shear forces and bending moments decreased, underscoring SSI's benefits in reducing seismic demands. This study offers valuable insights into bridge structures' dynamic behavior under seismic loading, emphasizing the importance of SSI in seismic design practices. The results are crucial for developing resilient bridge designs capable of withstanding complex SSI during earthquakes. [ABSTRACT FROM AUTHOR]

Alkali Activated Concrete (AAC), which utilizes industrial byproducts such as fly ash and slag, has emerged as a promising eco-friendly substitute. This paper evaluates the mechanical properties and environmental benefits of AAC, emphasizing its potential to replace Ordinary Portland Cement (OPC) in contemporary constructions. It examines the geopolymerization process, where aluminosilicate materials react in an alkaline environment to create a binder. The results show that AAC achieves optimal compressive strength with a 3% alkaline activator dosage, while higher dosages up to 5% decrease strength. Additionally, a silicate modulus of 1.25 provides the best compressive strength. The results also indicate that AAC, with a 1.25 silicate modulus and 3% activator dosage, outperforms control concrete in split-tensile strength and flexural strength assessments. Furthermore, AAC substantially lowers the carbon footprint of construction materials. This reduction is further enhanced by lower energy consumption during the manufacturing process, highlighting AAC's contribution to sustainable construction practices. The findings confirm that AAC not only matches but often surpasses the performance of traditional concrete, making it a viable and environment-friendly alternative with excellent mechanical properties. Transitioning to AAC can significantly help the construction industry achieve its sustainability goals, fostering more responsible building practices for the future. [ABSTRACT FROM AUTHOR]

The paper delves into the seismic performance of braced corrugated shear panels, examining the impact of varying thickness and depth of corrugations. Utilizing models with thickness ranging from 6 mm to 10 mm and depths of corrugations spanning 20 mm to 100 mm, nonlinear cyclic analyses are conducted under cyclic loading conditions. The results indicate that increasing thickness demonstrates substantial enhancements, with a 40% surge in energy dissipation capacity, a 20% rise in ultimate load resisting capacity, and a doubling of drift. However, deeper corrugations yield significant energy dissipation, and ultimate load increases up to a depth of 40 mm, beyond which a decline in energy dissipation capacity is noted. The study underscores the importance of optimizing thickness and depth configurations, with the findings revealing that simultaneous increase in both parameters may lead to panel overstiffening and diminished energy dissipation capacity. Overall, these insights provide valuable guidance for enhancing the seismic resilience of braced corrugated shear panels. [ABSTRACT FROM AUTHOR]

Pushover analysis is used to investigate how far into the inelastic range a building can go before it is on the verge of a total or partial collapse. In this paper, an eightstory structure is considered for evaluating the structural performance using pushover analysis, based on parameters such as moment curvature, ductility, overstrength, interstory drift and detailed computation of base shear. The results reveal that the structure possesses sufficient ductility and overstrength; it is found to have reached only immediate occupancy level after subjecting it to earthquake. [ABSTRACT FROM AUTHOR]

Passive damping devices are a workable technology for structural response control of a variety of structures to seismic excitations. The paper develops a low-cost passive damping device using air and/or nitrile rubber flecks (NRF), a waste material from industries available locally. A prototype damping device comprising cylinder made from PVC pipe housing a piston with a rod with covered ends is fabricated. Entrapped air-cum-friction damper (EAFD) device has air entrapped in the cylinder subjected to sustained triangular, and ATC-24 displacement loading protocol offers force due to air compression and dissipates energy due to air viscosity and side wall friction. EAFD damper is further modified to include NRF of irregular shape on each side of the piston (EAFD-NRF), which might improve the energy dissipation capabilities of the device due to the porous form of the nitrile rubber. Both damping devices (EAFD and EAFD-NRF) are characterized under cyclic loading of different loading rates. It has been found that both passive damping devices show hysteresis behavior under cyclic displacement loading test performed pseudostatically. While the EAFD device sees energy dissipation by friction mechanism dominant over air viscosity, the EAFD-NRF device observes inelastic deformation of NRF leading to relatively lower energy dissipation vis-à-vis EAFD device due to the absence of a redispersion mechanism of NRF in the device. EAFD damper yields an average equivalent viscous damping ratio of 0.43, which is on a par with other metal-based passive damping devices. [ABSTRACT FROM AUTHOR]

Shear failure is a crucial criterion in reinforced concrete (RC) deep beams. The paper studies the behavior of five deep beams reinforced with varied shapes of reinforcement and CFRP sheets. Two samples were analyzed using the conventional type shear reinforcement; the third sample had truss-shaped shear reinforcement, combos of strut and tie; the fourth had a Rolled I section to better understand how deep beams behave compositely; and the fifth was conventional type beam wrapped with 1.8 mm thickness CFRP sheet, tested for shear. Several variables were investigated using Abaqus software, including S-Tresca stress, percentage of shear reinforcement, load versus deflection, shear stress and equivalent plastic strain. [ABSTRACT FROM AUTHOR]

The paper analyzes and designs rectangular edges supported by two-way solid slabs using ES EN 1992-1-1:2015. Slab design is often carried out either manually or with the use of design and analytical software. It is observed that some software cannot accept standard codes of a few countries. For example, currently, in Ethiopia, analysis and design of two-way solid slab are done using readily available Excel sheet template. But working with this might have many problems. Notably, the structure that is already analyzed by SAP or SAFE or any other international software application that uses International Codes cannot design a structure using ES EN 1992. For instance, Eurocodes designed by Excel sheet can create failure, uneconomical analysis and poor design result. In this paper, the slab is designed and analyzed based on the chosen concrete grade, reinforcement bar diameter and steel grade for calculations like load, moment, shear and deflection checking using the moment coefficient method and Microsoft Visual Basic 2010 for coding. All input values are given by the International Standard units and are also used to represent output values. Using manual calculations takes a lot of time and mostly the result is not correct. But using this computer program, computation accuracy can be increased and time can be saved. The procedure followed is: first the manual calculation has been done, followed by SADSE2021. The result is that both are 99.9% identical, and the disadvantage of this method is that it cannot be used to determine the detailed drawing. [ABSTRACT FROM AUTHOR]

Panels made using honeycomb sandwich technique can help aerospace manufacturers maintain weight and fulfill certain strength requirements. Rigidity, stress absorption, fatigue resistance, and resistance to weather, chemicals, fire and isolation are some of the key benefits of honeycomb panels. Due to mechanical and acoustical requirements for high strength and weight target, it is common to select a sandwich design with a cheap and recyclable core material. Among other things, honeycomb sandwich structures are used in ship hulls, automobiles and civil constructions. Usage of these designs is the best way to obtain high strength and title material utilization. In this paper, the designs of hexagonal and square honeycomb constructions are evaluated for the most favorable structural outcomes. A honeycomb panel was produced using SolidWorks software. The proposed model was subjected to structural analysis using LS-DYNA software for four distinct kinds of materials: copper, steel, titanium and aluminum. Finally, the simulation results are presented and discussed. [ABSTRACT FROM AUTHOR]

Reinforced Concrete (RC) buildings with irregularities, plan and vertical, are susceptible to seismic damage. Such buildings are constructed due to functional, space and aesthetic considerations. Most practical irregular RC buildings have coupled irregularities: plan or vertical or mixed. The seismic behavior of coupled irregular RC buildings is an active area of research. In the present paper, five RC building models with coupled reentrant corners and vertical geometric irregularities are developed along with the regular RC building model. L-shaped and stepped-shaped reentrant corners type plan irregularity is coupled with vertical geometric irregularity by changing plan dimension at each floor level of RC building models. Building models are analyzed for seismic forces following the Indian seismic design code. Seismic parameters--peak base shear, peak displacement, peak interstory drift ratio, modal analysis, normalized base shear and normalized overturning moment--are extracted. It is found that peak displacement and peak interstory drift ratio of coupled irregular building models shows a substantial increase vis-a-vis regular building models. Normalized base shear and normalized overturning moment increase for all coupled irregular building models, except building model BM-3, as compared to the regular building model. [ABSTRACT FROM AUTHOR]

The paper presents an approach to the Kirchhoff-Love Plate Theory (KLPT) using the Finite Difference Method (FDM). The KLPT covers the case of small deflections, and shear deformations are not considered. FDM is an approximate method for solving problems described with differential equations. It does not involve solving differential equations; equations are formulated with values at selected points of the structure. Generally, in the case of KLPT, the finite difference approximations are derived based on the Fourth-Order Polynomial Hypothesis (FOPH) and Second-Order Polynomial Hypothesis (SOPH) for the deflection surface. The FOPH is made for the fourth and third derivative of the deflection surface, while the SOPH is made for its second and first derivative; this leads to a 13-point stencil for the governing equation. In addition, the boundary conditions, and not the governing equations, are applied at the plate edges. In this paper, the FOPH was made for all of the derivatives of the deflection surface; this led to a 25-point stencil for the governing equation. Furthermore, additional nodes were introduced at plate edges and at positions of discontinuity (continuous supports/hinges, incorporated beams, stiffeners, brutal change of stiffness, etc.), with the number of additional nodes corresponding to the number of boundary conditions at the node of interest. The introduction of additional nodes allowed to apply the governing equations at the plate edges and to satisfy the boundary and continuity conditions. First-order analysis, second-order analysis, buckling analysis, and vibration analysis of plates were conducted with this model. Moreover, plates of varying thickness and plates with stiffeners were analyzed. Finally, a Direct Time Integration Method (DTIM) was presented. The FDM-based DTIM enabled the analysis of forced vibration of structures, with damping taken into account. In first-order, second-order, buckling and vibration analyses of rectangular plates, the results obtained were in good agreement with those of well-established methods, and the accuracy was increased through a grid refinement. [ABSTRACT FROM AUTHOR]

The paper evaluates sugarcane Bagasse Ash (BA) as a partial cement replacement material. Sugarcane BA is a byproduct of fuel blending in the sugar industry. It is the residual waste that remains after the economically viable sugar has been extracted from the cane. The disposal of the sugarcane waste in agriculture causes environmental problems. The cement industry also creates environmental problems due to carbon dioxide emissions during cement manufacturing. Initially, BA samples were collected from the rubble of the Arjo Didessa Sugar Factory. The crude BA was sieved with a 250 µm size sieve. The strength of grade C-25 concrete was designed using five different concrete mixture proportions ranging from 5 to 20% cement by weight, including a water-cement ratio of 0.45. The impact strength tests were conducted at 7, 14, 21 and 28 days of age for each replacement ratio. For the experimental work, a total of 60 cubic concrete specimens were cast for compressive strength tests and 15 cylindrical concrete specimens were cast for water absorption tests. Working compressive strength results indicated that BA could replace up to 5% of ordinary Portland cement concrete. [ABSTRACT FROM AUTHOR]

The paper aims at studying the structural response of cooling tower shell under wind loading. The calculated wind pressure is applied on a cooling tower at different heights and circumferential angles. The analysis is carried out for different shell thicknesses using FEA, and the response of cooling tower shell is observed in terms of deflection, hoop and meridional forces at 0? meridian. The circumferential pressure distribution given in IS 11504: 1985 code is expressed as Fourier cosine series in the present study, and the calculation is carried out for 15? interval and compared with the coefficients obtained from IS 875 (Part 3): 1987. It is observed that the deflection of cooling tower shell decreases, whereas the hoop and meridional forces increase with increase in shell thickness. The hoop and meridional forces are not much affected above throat level for different shell thicknesses. [ABSTRACT FROM AUTHOR]

The paper explains the impact of metallic dampers on the seismic performance of a nine-story steel moment frame. The design technique for an X-shaped Added Damping and Added Stiffness (ADAS) type steel damper is examined. With a minimal activation load, the damper is designed to give well before the building yields. A series of Finite Element (FE) simulations were used to verify the performance of the proposed device under constant and increasing cycle loads. The suggested steel dampers exhibited comparable hysteretic curves and steady hysteretic behavior, according to the simulation findings. ABAQUS software was used for FE analysis. Then, utilizing El centro (1940) ground motion recordings in SAP2000 software, nonlinear time history studies were done to evaluate the seismic behavior of steel frames using this sort of passive control system. Through the dampers, the seismic reactions of the frames were investigated and compared in terms of maximum displacement, maximum story drift, roof displacement time history, input energy and dissipated energy. The results showed that the constructions with dampers outperformed the original structure in terms of seismic performance. [ABSTRACT FROM AUTHOR]

The paper presents experimental investigations of metakaolin and fly ash combination of cementitious material used as admixture to produce high strength. Cement was replaced with 5%, 10%, 15%, 20% and 25% by metakaolin with addition of 10% fly ash. The paper evaluates the mechanical behavior of cement concrete using metakaolin and fly ash compared with control specimens. [ABSTRACT FROM AUTHOR]

The vulnerability of Reinforced Concrete (RC) building systems to progressive collapse has turned out to be a challenging task for professional structural engineers looking to prevent total failure on account of nearby damage. The paper estimates the behavior of such buildings under several scenarios of misplaced columns at different floor stages and their capacity for progressive collapse. The study has been conducted following the General Services Administration (GSA) guidelines for progressive collapse evaluation and design. The progressive collapse of a 10-story structure subjected to the simplest gravity load is taken into consideration and the column is eliminated at one place to evaluate the damage spread; columns at diagnosed crucial locations (corner, middle and interior) are removed in line with the GSA guidelines. Static analysis is done using ETABS. For each case, the consequences are considered in terms of Demand Capacity Ratio (DCR) at critical sections, and the structure is assessed for its susceptibility to progressive collapse. The shear wall is made available on the component where collapse occurred and DCR values are mentioned. By providing the shear wall to the structure, the progressive collapse of a structure due to accidental load may be controlled. [ABSTRACT FROM AUTHOR]

Fine aggregate plays a vital role in the composition of both concrete and mortar in construction work. Excessive utilization of river sand as fine aggregate in building construction aggravates environmental degradation and underscores the need for alternate sources in the context of sustainable construction. The paper focuses on the use of crushed pebbles as a partial replacement for fine aggregate in the production of concrete. Fine aggregate was replaced partially by Pebble Sand (P-sand) in different proportions (20%, 30%, 40% and 50%) by the weight of fine aggregate in M30 grade of concrete. An experimental investigation was carried out to evaluate the mechanical (compressive, flexural and modulus of elasticity) properties of concrete with P-sand as a partial replacement for fine aggregate. The results indicate that the specimen casted with 40% replacement of P-sand to fine aggregate gave higher strength when compared to conventional concrete. [ABSTRACT FROM AUTHOR]

Wind-induced ovalling effect on the cylindrical wall of single flexible empty steel silo has been studied by various investigators in the past. The paper presents the same effect on cylindrical wall of ground elevated rigid (reinforced concrete) silo using a very simplified analytical approach, which may easily be accessed by practicing engineers for the purpose of design. An approximate analysis of circular cross-section of silo is performed to evaluate the effect of ovalling, but the same is much on conservative end, and also it cannot provide the effect to be taken into consideration for the entire height of the silo. To make the design procedure simple and costeffective, a few case studies have been performed using the actual wind load distribution and numerical/finite element model in Abaqus. The results obtained from the threedimensional finite element model of the silo show that the values of deformation and stresses obtained are much on lower end compared to the results of approximate analysis in bending of silo wall, whereas it also evaluates longitudinal stress which is equally significant. The paper also proposes graphs/charts to derive a modification factor over the values obtained by analytical/approximate method so that the designers and practicing professionals may take appropriate measures in the process of designing and detailing of the silo wall without going for detailed investigation of the model under consideration. [ABSTRACT FROM AUTHOR]

In construction, the foundation is an integral part of a structure and its function is to transfer the building loads safely into the ground and to keep the settlement within permissible limits. Here, soil is an essential component of the earth's surface that transfers building load through the foundation. Generally, different foundations are adopted depending on the different soil conditions and number of floor loads to be transferred to the deeper strata. Therefore, improving the bearing capacity of soil by experimental stabilization achieves better strength at required shallow depth. This paper develops an improved bearing capacity for shallow foundations on clays considering actual soil constitutive behavior. The geopolymer-stabilized soil specimens were synthesized and characterized with compressive strength testing and effective soil stabilizer for clay soils. [ABSTRACT FROM AUTHOR]

The paper investigates the hysteretic behavior of the semirigid steel beam-column connection due to cyclic loading. Three different models with end connections are modeled for the analysis using ABAQUS software: Model 1 with extended end plate connection without column stiffeners; Model 2 with extended end plate connection with column stiffeners; and Model 3 with seat and cleat angle connection. The cyclic load is applied as per the loading protocol provided by the AISC seismic provisions. The results represent the hysteretic behavior of the connections. The area of the hysteresis curve of each loading cycle provides the dissipated energy at each cycle of loading. The addition of the stiffness to the connection against cyclic loading results in change of behavior of the hysteresis curves, i.e., the behavior of hysteresis curves of model 2 and model 3 is stable compared to that of model l. The energy dissipation capacity of model 1 is less compared to that of model 2 and model 3, as the column stiffeners in model 1 and the outstanding legs of the angles in model 2 provide additional stiffness to the connection against cyclic loading. The stiffness of the connection starts degrading after each cycle of load. [ABSTRACT FROM AUTHOR]

Quality Monitoring (QM) with Cumulative Sum (CUSUM) system can result in economizing Ready Mix Concrete (RMC) through optimal control of target strength and reduction of risk against rejection. To overcome the problems associated with the conventional 28-day compressive strength test, correlations are established between accelerated and the standard 28-day cube strength to predict the 28-day strength from the early age strength itself. The paper demonstrates the lack of reliability of single correlation itself along the production time of RMC. The correlations vary with water-to-cement and with type of cement. Hence, it is demonstrated that correlation is concrete-specific. Further, it also demonstrates that using specimens having wide variation in the batching may result in poor correlation. CUSUM plots of mean and range for cube strength obtained by Monte-Carlo simulation demonstrate the utility of prediction through such correlation in QM and a methodology for monitoring the correlation itself. [ABSTRACT FROM AUTHOR]

High Performance Concrete (HPC) plays a very important role in some constructions such as hydraulic structures, high-rise building and long bridges. The paper is an exploratory investigation of fiber reinforced HPC for their mechanical properties by replacing the coarse and fine aggregates with crushed concrete waste and foundry sand, respectively. Foundry sand is replaced 0% to 40% with 5% interval, and crushed concrete waste is replaced 0% to 40% with 10% interval. The mechanical properties like fatigue strength, impact strength, compression strength, flexural strength, split tensile and shear strength of HPC with and without addition of fibers are evaluated. For manufacture of HPC, M-80 Grade concrete has been chosen. According to IRC44:2017 guidelines, the mix design process is conducted. Conventional dosage of superplasticizer is managed in the concrete to make a better execution. Polypropylene fibers of 0.3% by total cement weight are used. Mechanical properties are obtained by manufacturing the particular sizes of mold cured for 7, 14 and 28 days for different tests, and results are tabulated for respective days and conclusions are obtained. [ABSTRACT FROM AUTHOR]

In terms of building serviceability, the relative qualities of concrete are quite important. In this paper, the impact of recycled aggregate's physical and mechanical properties were studied and the concept of concrete is explained. Water-binder (w/b) ratios 0.28, 0.30 and 0.32 were used. With a substitution percentage of 0%, 10%, 12.5%, 15% and 20% of natural material, recycled aggregates were taken into account. Optimization was done using Minitab software to achieve the best combination of materials for obtaining High Performance Concrete (HPC). [ABSTRACT FROM AUTHOR]

In recent years, the application of shear wall system in a Reinforced Concrete (RC) building is widely used to minimize seismic consequence. Furthermore, concentrated steel bracing systems are used in steel structure buildings for the same reasons. Both the systems have a significant impact on the structural performance. Although both systems are used for the same reasons, their effect shows unequal variations and behavior against seismic load. This is the reason that the values of response factors are miscellaneous for varying structural systems. The paper investigates the behavior of RC structures considering the shear wall and steel bracing systems. A comparison is made on asymmetrical plus shape structure, and analysis is done using Response Spectrum Method (RSM) on G+7 RC frame structures. Shear wall and bracings are placed at different locations and frames are modeled using ETABs software. Parameters like base shear, displacement, storey drift, time period and storey acceleration are compared in terms of stiffness and strength. [ABSTRACT FROM AUTHOR]

The advantage of adopting wall panels with lighter densities as precast wall panels (being developed in the recent past) needs to be assessed from the safety and serviceability point of view under loading. The paper presents a comparative analysis of multistoried buildings with reduced wall densities against ordinary brick walls. The type of building being considered for analysis is a G+5 RCC framed structure for residential usage. It was observed from the results that the final carpet area of the building increased when the panels were used in place of walls. With the decrease in the density of wall, no appreciable change in the volume of concrete was observed, but the savings in steel got reduced. [ABSTRACT FROM AUTHOR]

Beams are the major structural elements that carry and transfer the loads and are designed for bending and shear. Prismatic beams having uniform cross-section are commonly used for short and medium spans, whereas haunched beams are non-prismatic with varying cross-section. Shear wall structural systems are used to increase the stiffness of the structure to resist the lateral loads acting on a structure. The paper considers a 25-storey rigid frame structure and compares the performance of prismatic beams and haunched beams. Also, a comparative study of haunched beam frame with shear wall and without shear wall is made. The structure is analyzed for earthquake loads by both linear and nonlinear analysis using ETABS2015. Linear analysis includes both equivalent static method and dynamic response spectrum method. Nonlinear analysis is performed by pushover analysis. On the basis of the structural parameters studied, the general conclusion is that haunched beams provide more efficient use of concrete and steel reinforcement and reduces the weight of the structure. [ABSTRACT FROM AUTHOR]

Considering the need for developing an alternative construction material, the paper discusses the feasibility of alkali-activated Self-Compacting Geopolymer Concrete (SCGPC). The paper also presents the rheological behavior of fiber-reinforced SCGPC under the effect of steel fibers, dosage of SP and effect of extra water. Fluid-Binder (F/B) ratio of 0.6 with 1% of steel fibers with different dosages of superplasticizer, i.e., Glenium SKY 8630, was considered. The flow characteristics and compressive strength of the samples were studied. The results showed that with 6% and 5% of SP and 5% of extra water content, the mix was satisfying, the flowability properties and the compressive strength were maximum among all other mix proportions. [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]

Concrete Filled Steel Tube (CFST) is a composite material which is currently used in high-rise buildings due to excellent seismic-resistant structural properties. CFST columns combine the best characteristics of both steel and concrete material, since they have high strength, ductility and high stiffness. The paper investigates the effect of slenderness ratio on behavior of CFST columns under axial compression for mix design of M40 grade concrete with w/c 0.45 as per IS: 10262 (2019) for 28 days curing period. Nine specimens with heights ranging from 350 mm to 750 mm with intervals of 50 mm were tested under axial compression. The slenderness ratio (L/D) is varied from 3 to 7. The effect of slenderness ratio on ultimate load carrying capacity is studied. It is observed that an increase in slenderness ratio gradually decreased the ultimate load carrying capacity of CFST. The large slenderness ratio specimens resulted in failure by buckling. The shorter columns are failed by crushing of the concrete. The effect of failure mechanism is also studied. It is noticed that as load approached the ultimate load the strains gradually increased. A relation between load and deflection is plotted. The effect of varying slenderness ratios on axially loaded CFST columns depends upon the geometric and material properties under short-term and long-term loadings. [ABSTRACT FROM AUTHOR]

The use of optimization process is a much-needed step in the field of construction today. But optimization is not being used very efficiently in structural engineering. Weight optimization is one of the structural optimization processes which optimizes the weight of the material used in the construction. The process provides an optimum area of cross-section for the steel sections. By optimizing the weight, the material cost has been reduced. It helps in improving the economic sustainability. The paper presents a study of optimization of trusses using genetic algorithm. The trusses considered for optimization are a two-bar truss, a three-bar truss and a ten-bar truss. The software used for this process is MATLAB2013a. The results are cross-checked using STAAD.Pro and manual calculations. [ABSTRACT FROM AUTHOR]

Passive control force is obtained from Shape Memory Alloy-based Tension Sling Damper (SMA-TSD) fitted to a seismically excited 10 storeyed shear building. One-dimensional Tanaka model is considered to represent the hysteresis behavior of SMA-TSD. This exhibits a nonlinear relationship between damper force and input states; hence, its implementation with linear system is a nontrivial task. In the paper, SMA-TSD is represented by Voigt model comprising equivalent stiffness and damping components derived by mapping it with flag-shaped hysteresis loop defined by Tanaka model. The results for controlled response of the buildings are obtained in terms of peak response quantities, i.e., interstorey drift, displacement and acceleration. One SMA-TSD fitted at ground storey of the building yields moderate control (~29%) in peak response quantities. However, peak response quantities reduce substantially (~53%) for different levels of El Centro seismic excitations and moderately (~19%) for 50% Kobe seismic excitation when two SMA-TSDs are used in the building. The efficacy of SMA-TSD implemented in the study is a function of design parameters, diameter of SMA wire and length of SMA wire, and can be optimized. [ABSTRACT FROM AUTHOR]

Design of a pile foundation involves solving the complex problem of transferring loads from the structure through the piles to the underlying soil. It involves the analysis of a structure-pile system, the analysis of a soil-pile system and the interaction of the two systems, which is highly nonlinear. Close cooperation between the structural engineers and geotechnical engineers is essential to the development of an effective design. Many factors must be considered when selecting an appropriate foundation for a hydraulic structure. Information is presented to identify the feasible foundation alternatives for a more detailed study. This coordination extends through plans and specifications, preconstruction meetings and construction. Some of the critical aspects of the design process require coordination. In this paper, a comparative study is made on the sesmic behavior of Soil-Structure Interaction (SSI) of RC building with homogeneous and non-homogeneous soil conditions. [ABSTRACT FROM AUTHOR]

Cold Formed Steel (CFS) members are generally thin-gauged bent steel sheets or rolled into different shapes at ambient temperature which can carry significant load. They are used as the main component for construction of light gauge steel frame structures. However, being a thin-walled member, they often show many instability phenomena such as local buckling, distortional buckling and global buckling. Effective Width Method (EWM) and Direct Strength Method (DSM) are used to calculate the strength of CFS members. American standards (AISI S100) recommend both methods, whereas British Standard (BS 5950-5) uses EWM for design. DSM requires computational tools such as CUFSM (Constrained and Unconstrained Finite Strip Method), which is an open source software to determine the strength and buckling behavior of member. In this paper, a simple portal frame is designed using Tubular hot rolled steel section and CSF sections, and required quantity of steel has been compared. Also, design strengths of different cold formed Steel Stud Manufacture Association (SSMA) studs under compression (braced column), bending (laterally stable beam), and shear have been compared as per provisions mentioned in American (AISI S100) and British (BS 5950-5) standards. The results of the strength comparison can be further used as reference material by engineers. [ABSTRACT FROM AUTHOR]

The paper examines the porousness qualities of solid samples utilizing 'alccofine' and M20 grade cement concrete. The variety was concentrated on the samples exposed to solidification supplanted by different rates of alccofine (0, 10, 12, 14 and 16 rates respectively). Casted samples are relieved in climatic temperature and solidified properties of cement are done at 7 and 28 days, and Rapid Chloride Permeability Test (RCPT) was done at 28 and 35 days. The results showed that the specimen permits 2000 to 4000 Coulombs giving medium rating according to ASTM 1202 (ASTM C1202, 2010). The RCPT showed improved opposition for chloride penetrability and low pace of consumption chance level. [ABSTRACT FROM AUTHOR]

In elastic method of analysis, loaded structural elements do not reach up to collapse stage and the failure pattern cannot be traced out. Effect of the lateral forces, i.e., wind force and seismic force, makes the structure collapse and structural elements reach beyond the yield point. So, during seismic loads, structural elements show inelastic behavior. For inelastic behavior, suitable stress-strain curves have to be derived and analysis has to be performed. An attempt has been made in this paper to evaluate the behavior of the five-storey RC frame structure using SAP2000 by adopting the nonlinear static analysis and considering different modeling approaches. Mander's and Kent and Park's modeling approaches have been adopted for the performance of nonlinear static analysis and results are tabulated. [ABSTRACT FROM AUTHOR]

Although vast research has been carried out on geopolymer concrete, still there is no well-established methodology for selecting the parameters such as molarity of NaOH solution, Na2SiO3 to NaOH ratio, alkali to binder ratio and curing methods. The paper aims at providing a basic idea of the effect of these parameters on the performance of geopolymer concrete. [ABSTRACT FROM AUTHOR]

Large amount of carbon dioxide is released in the environment during cement production, resulting in global warming. There is a need to alter the cement by some natural resources having pozzolonic properties. Calcium bentonite powder is a naturally available material having pozzolonic properties able to replace cement partially. The contribution of mineral admixture alccofine to concrete reduces thermal, shrinkage cracks and increases strength as compared to conventional concrete. Alccofine boosts the compressive strength of concrete. The paper proposes that cement be replaced with calcium bentonite (5%, 7.5%, 10% and 12.5%) and alccofine (5%, 7.5%, 10% and 12.5%), respectively. Varaplast SP-123 (superplasticizer) is used for good workability with the concrete, and it is taken by the weight of cementitious material. Cubes and cylinders were cast in accordance with M30 design mix, and compressive strength and split tensile strength were evaluated for 7 days and 28 days curing period; workability tests (slump cone) were conducted and compared with conventional concrete, and based on the test results, various strengths were identified. [ABSTRACT FROM AUTHOR]

The plane concrete possesses very low tensile strength, limited ductility and little resistance to cracking. The addition of small closely spaced and uniformly dispersed fibers to concrete would act as crack arrester and would substantially improve its static and dynamic properties. This paper presents the variation in strength characteristics of fly ash bricks by varying the percentage of fibers and class F fly ash. The percentage of fibers is varied from 0.25% to 0.5%. An effort for an alternate approach in the experimental manufacturing of brick was accomplished using various supplementary cementing materials like class F fly ash and hydrated lime and fibers such as jute and banana are used as key ingredients in the present investigation. Recycling such wastes by utilizing them in building materials is a moderate solution for the environmental pollution issues. Much emphasis is laid on energy-saving and economy. In this experimental study, an attempt has been made for such an alternate approach. [ABSTRACT FROM AUTHOR]

The paper aims at evaluating the value of Response Reduction Factor (RRF) for 3D model of steel buildings. Nonlinear static pushover analysis was carried out to assess the structural performance of different bracing systems in steel buildings of 4, 6 and 8 storeys. Five structural configurations were used, namely, Moment Resisting Frames (MRFs), Diagonal Braced Frames (DBFs), X Braced Frames (XBFs), V Braced Frames (VBFs) and Chevron Braced Frames (CBFs). The effect of the parameters, such as the height of building and the type of bracing system, was investigated on the value of RRF. The results show that RRF decreases as the height of the building increases and also this factor is on a higher side for braced frames than unbraced frames. The paper also shows that the values of RRF prescribed by IS code are on a very safer side than the actual values obtained, thereby giving rise to uneconomical design of structures. [ABSTRACT FROM AUTHOR]

A general analytical formulation is presented in this paper to investigate the large amplitude vibration behavior of simply supported slender uniform beams with end elastic rotational restraints. This boundary configuration of the beam can also be called spring-hinged beam. The classical Rayleigh-Ritz method is used to obtain the general analytical solution. One-term admissible function for the lateral deflection is easy to assume, but the same for the axial displacement, compatible with the lateral deflection, is not straightforward. A method is developed in this paper to derive the admissible function for the axial displacement from the von-Karman type nonlinear strain-displacement relation. The advantage of the present method is that both the admissible functions contain the same undetermined coefficient. This simplifies the use of the RR method. Numerical results obtained from the present formulation compared well with those available in literature. [ABSTRACT FROM AUTHOR]

The paper deals with the analysis and structural shape optimization of box girder bridges with curved planform. The finite element analysis of a box girder bridge was carried out and then optimized using ANSYS. The aim of this paper is the shape optimization of a box girder bridge with strain energy minimization as objective under a constraint that the total volume of the structure should remain constant. The shape of a box girder bridge was optimized under two load cases: (1) Load is applied on the top flange which was above the inner web; and (2) Load is applied on the top flange which was above the middle web, and the results are validated by comparing them with a benchmark problem (Ozakca and Taysi, 2003). The structural optimization variables used were the design variables (length variables and thickness variables), state variables (volume), and the objective function (minimization of strain energy). In load case 1, the strain energy of the structure was reduced by 94.6% (as against 62.2%, by Ozakca and Taysi), and in load case 2, the strain energy of the structure was reduced by 75.2% (as against 65.5%, by Ozakca and Taysi) which is a significant improvement. [ABSTRACT FROM AUTHOR]

The section of gravity dam is so designed and shaped that its weight is sufficient to ensure stability against the effects of all imposed forces. The important complex factors that affect the stability of the dam are traditional calculation methods and mechanics of materials. These take a lot of time in the calculation and thus cannot give a more comprehensive analysis. So, the finite element simulation technology is widely used. Based on this, there exist many kinds of software of the finite element, and ANSYS software is one of them. In this paper, an effort has been made to apply various concepts to the actual size of "Bellary Nala Irrigation Project (Belagavi)" dam. The first step of simulation is aimed at validating the models developed by comparing them with manual results. By Finite Element Analysis (FEA), a twodimensional Finite Element Model (FEM) of a gravity dam is proposed using ANSYS APDL18.2. Dams with full reservoir and empty reservoir conditions are analyzed. Normal stress, principal stress, shear stress and deflection along the crest of the dam are observed. It is observed that when the reservoir is empty, the direction of vertical acceleration does not have a significant role in the stress distribution results, but it affects the displacement of the crest of the dam. The stresses developed with flexible base are more than that of rigid base. Also, when the reservoir is full, the openings in the dam induce higher stresses. [ABSTRACT FROM AUTHOR]

Comparing experimental results on the shear capacity of Steel Fiber-Reinforced Concrete (SFRC) beams without mild steel stirrups to the ones predicted by current design equations and other available formulations still shows significant differences. The paper proposes the use of Artificial Intelligence (AI) to estimate the shear capacity of these members. A database of 430 test results reported in the literature is used to develop an Artificial Neural Network (ANN)-based formula that predicts the shear capacity of SFRC beams without shear reinforcement. The proposed model yields maximum and mean relative errors of 0.0% for the 430 data points, which represents a better prediction (mean Vtest/VANN = 1.00 with a coefficient of variation of 1 ? 10-15) than the existing expressions, where the best model yields a mean value of Vtest/Vpred = 1.01 and a coefficient of variation of 27%. [ABSTRACT FROM AUTHOR]

The paper presents foamed concrete with a density of 1000 kg/m3 by replacing fine aggregate of 50% fly ash and 50% GGBS with addition of different percentages of polypropylene and recron3s fibers (0%, 0.1%, 0.2%, 0.3%, 0.4% and 0.5%). Also, the physical and mechanical properties of foam concrete are studied. The results indicate that fibers gave the optimum result by a certain percentage of fiber dosage by increasing compressive strength, flexural strength and split tensile strength. The water absorption properties are also measured. The foam concrete also tested the bonding properties of fiber, foam and cementation materials. The total number of specimens included 24 beam, 24 cylinder and 24 cubes. They kept curing for 28 days. To check the bonding of material, Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS) tests were conducted. [ABSTRACT FROM AUTHOR]

Self-curing concrete is one of the special concretes in mitigating insufficient curing due to human negligence, paucity of water in arid areas, inaccessibility of structures in difficult terrains and in areas where the presence of fluorides in water badly affects the characteristics of concrete. The aim of the paper is to evaluate the use of watersoluble Polyethylene Glycol (PEG) as self-curing agent with partial replacement of conventional fine aggregate with lightweight fine aggregate and to optimize the quantity of PEG. Flexural behavior of self-curing concrete of M30 grade is casted by replacing optimum percentage of natural fine aggregate with lightweight fine aggregate and optimum percentage of PEG by weight of cement. The fine aggregate was partially replaced with 25% quarry dust. From the optimum percentage of lightweight fine aggregate replacement, optimum percentage of PEG -400 was found out by varying the percentage of PEG from 0%, 0.5%, 1% and 1.5% by weight of cement for M30 grade of concrete. The compressive strength, split tensile strength and flexural strength of self-curing concrete with varying quantity of polyethylene glycol are evaluated and compared with the conventional concrete specimen. [ABSTRACT FROM AUTHOR]

Headed studs are commonly used as shear connectors to transfer longitudinal shear force at the interface between steel and concrete in composite structures (e.g., bridge decks). Code-based equations for predicting the shear capacity of headed studs are summarized. The paper proposes an Artificial Neural Network (ANN)-based analytical model to estimate the shear capacity of headed steel studs. 234 push-out test results from the previous published research were collected into a database in order to feed the simulated ANNs. Three parameters were identified as input variables for the prediction of the headed stud shear force at failure, namely, the steel stud tensile strength, diameter and the concrete (cylinder) compressive strength. The proposed ANN-based analytical model yielded maximum and mean relative errors of 3.3% and 0.6%, respectively, for all the collected data. Moreover, it is illustrated that the neural network approach clearly outperformed the existing code-based equations, which yielded mean errors greater than 13%. [ABSTRACT FROM AUTHOR]

Generally, conventional concrete does not conduct electricity but conducts when some conductive components are added to the conventional concrete. This concrete is called Electrically Conductive Concrete (ECC). The paper studies the suitability of industrial waste materials for making ECC. Different industrial wastes such as lathe turns of aluminum and steel, powder of brass and cast iron, copper slag and lignite bottom ash were used as conductive materials. It was observed that industrial wastes such as bottom ash and copper slag were suitable materials for making concrete by replacing fine aggregate. From the number of trials, the optimum quantity of industrial waste to replace the conventional fine aggregate river sand was found. Then two different ECC mixes, Mix with Bottom Ash (MBA) and Mix with Copper Slag (MCS), were prepared based on volume basis. The strength, electrical resistivity and thermal properties of both the ECC specimens were studied. [ABSTRACT FROM AUTHOR]

The paper makes an attempt to parametric study the tall structures with diagrid structural system. Diagrid is an exterior structural system which resists the lateral forces by axial actions of diagonals provided in periphery. The main objective is to determine the optimum module size of diagrid. The study considers five steel buildings having typical plan area, and loadings of 12, 24, 36, 48 and 60 storeys were analyzed for the 4, 6 and 8 storey diagrid module size. The analysis was carried out in ETABS 2017 software. Various parameters like fundamental time period, maximum storey displacement, maximum storey drift, maximum base shear were considered. [ABSTRACT FROM AUTHOR]

The significance of incorporating Soil Structure Interaction (SSI) effect in the analysis and design of RC framed structure is increasingly recognized but still has not penetrated to the large level owing to various complexities involved. It is a well-established fact that the SSI effect considerably influences the design of high-rise storey buildings subjected to lateral seismic loads. The shear walls are often provided in such structure to increase the lateral stability to resist seismic lateral loads. The paper presents a linear soil structure analysis of a G + 15 storey RC shear wall building frame resting on isolated footing and raft foundations and supported by deformable soil. The modeling and analysis is carried out using ETABS 2015 software under gravity loads and seismic loads. The interaction work analysis is carried out with and without shear wall to study the effect of inclusion of shear wall on the forces in the footing due to settlement of soil mass. Both the frame and soil mass are considered to behave in a linear elastic manner. It is observed that the SSI effect significantly alters the time period, base shear, stiffness, storey drift and storey forces of the building due to soil settlement. The non-interaction analysis of space frame shear wall suggests that the presence of shear wall significantly reduces time period and displacement of the building but the interaction effect causes restoration of time period and displacement to a great extent. [ABSTRACT FROM AUTHOR]

Fabrication technology and structural engineering states-of-the-art have led to a growing use of slender structures, making them more susceptible to static and dynamic actions that may lead to some sort of damage. In this context, regular inspections and evaluations are necessary to detect and predict structural damage and establish maintenance actions able to guarantee structural safety and durability with minimal cost. However, these procedures are traditionally quite time-consuming and costly, and techniques allowing a more effective damage detection are necessary. This paper assesses the potential of Artificial Neural Network (ANN) models in the prediction of damage localization in structural members; as function of their dynamic properties--the three first natural frequencies are used. Based on 64 numerical examples from damaged (mostly) and undamaged steel channel beams, an ANN-based analytical model is proposed as a highly accurate and efficient damage localization estimator. The proposed model yielded maximum errors of 0.2 and 0.7% concerning 64 numerical and three experimental data points, respectively. Due to the high-quality of results, the authors' next step is the application of similar approaches to entire structures based on much larger datasets. [ABSTRACT FROM AUTHOR]