Dead Load Research Articles

Numerical design optimization of real size complex steel space frame structures using a novel adaptive cuckoo search method

AbstractIn this study, real size complex steel space frame structures are numerically designed to achieve optimal design weight. For this aim, standard cuckoo search algorithm is rectified through a newly proposed adaptive method over two fundamental algorithmic parameters of alien egg probability detection (Pa) and step size control (α) to overcome incompetency of trapping into local optima. Besides, to strengthen exploitation phase of newly proposed algorithm, it is boosted with greedy selection (GS). So, novel algorithm has more promising exploration and exploitation capabilities. An 8‐story, 1024‐member and a 20‐story, 1860‐member real size complex steel space frame structures are selected as design examples. Also, initially to verify the supremacy of novel algorithm, a well‐known welded beam is optimized as a benchmark structural design problem. Afterwards, the steel space frame structures are optimally designed via novel algorithm. Since ready steel section lists are utilized as selection pool for design variables, discrete programming problem is come into existence. The dead, live, snow, and wind design loads acting on frame structures are calculated in direction of ASCE 7‐05 provisions. Furthermore, the structural design constraints are determined from LRFD‐AISC specifications. Eventually, the newly proposed adaptive cuckoo search algorithm boosted with GS presents outstanding algorithmic performance.

Numerical and experimental study of a segmentally prefabricated orthotropic steel–ultra-high-performance concrete composite deck for long-span cable-stayed bridges

Utilizing the high strengths, toughness, and durability of ultra-high-performance concrete (UHPC), a segmentally prefabricated orthotropic steel–UHPC composite deck (POSUCD) system has been developed for long-span cable-stayed bridges. The deck system combines an orthotropic steel deck (OSD) with a reinforced UHPC layer using notched perfobond strips (NPBLs). The UHPC layer is prefabricated onto the OSD of the girder segment in the factory to form the POSUCD. After the precast UHPC layer is cured, the girder segments are transported to the bridge site and assembled. The precast UHPC layers are then connected via transverse wet joints before tensioning stay cables. Against the background of the Danjiangkou Reservoir Bridge with a main span of 760 m, finite element (FE) analysis was conducted to examine the stress state and flexural tests were carried out on local full-scale models to verify the feasibility of POSUCD. The results show that the prefabricated UHPC layer reduces the maximum static compressive stress of the steel deck in the girder system by 21%, and the stress ranges at fatigue-prone details of the steel deck are decreased by 28%–90% compared to traditional OSDs with asphalt overlay. Since the prefabricated UHPC layer helps withstand dead axial load in the main girder, the high compressive strengths of UHPC can be utilized more effectively than in deck systems with UHPC only used as a cast-in-situ overlay to resist vehicular wheel loads. The transverse wet joint interfaces were identified as the weakest aspect of the POSUCD, whether under tension or compression; however, their nominal flexural strengths along the longitudinal direction meet the required design standards. The shear resistance of NPBLs was also well confirmed by the minimal interfacial slip on the specimen when it reached the ultimate capacity under positive bending moment.

Applied development of sustainable-durable high-performance lightweight concrete: Toward low carbon footprint, durability, and energy saving

Over the past few decades, the utilization of Lightweight Concrete (LWC) has emerged as a promising solution for reducing the dead load of structures. However, a key concern associated with the reduction of concrete density, is the potential decrease in mechanical and durability properties. This paradox necessitates a precise mix design that fulfills the requirements of high-strength concrete. This article investigates the influence of Lightweight Expanded Clay Aggregate (LECA) on the strength and durability, and thermal conductivity of Lightweight High-Performance Concrete (LWHPC). The LWHPC mixes explored in this study include sustainable cement solutions such as Portland limestone cement, varying water/binder ratios of 0.3 and 0.35, Leca contents ranging from 5 % to 20 % by volume, and two different pozzolanic supplements, namely silica fume and fly ash, which can be reducing porosity and enhancing durability and mechanical strength. The durability properties of the concrete were assessed through water absorption, electrical resistivity, and chloride migration profiles. Additionally, thermal conductivity measurements were conducted on all specimens. The results indicate that LWHPC, with a lower water/binder ratio, exhibits higher compressive strength and lower absorption, indicating good concrete quality. Generally, after a curing period of 90 days, mixtures with a density exceeding 1700 kg/m3 demonstrated superior durability characteristics. Furthermore, LWHPC mixes in both water/binder ratio groups displayed significantly low thermal conductivity with increasing lightweight aggregate content.

Correction Factor Method As A Substitute For Sequential Construction Analysis Of Buildings

Abstract: Within the sphere of structural analysis, a method of paramount importance emerges - the Correction Factor Method. Unlike conventional approaches, this method stands as a stalwart against the complexities of non-linear structural behavior. It pioneers a path that diverges from the linear norm, offering precision and insight where others falter. The structural parts of the building are analyzed in one step using linear static analysis method by assuming that the structure will be subjected to full load after the finishing of the construction completely. In reality things work in other way the dead load from each structural members and finishing materials are imposed in different stages as the structure is constructed storey by storey. Similarly the stability of frame changes at every stage of construction. Because of this changes the loads assumed in conventional analysis vary in the construction process and the results obtained in the traditional analysis will be unstable. Thus the structural frame should be analyzed in every structural construction stage by keeping variation of loads. This process is called as Construction Stage Analysis this process considers all the uncertainties precisely. This process is a time consuming process as the analysis is a complex process. Thus Correction factor method can be introduced where the analysis time can be reduced and the results will be accurate to Construction Stage Analysis. In this project multistoried reinforced concrete building frames with different number of floors are analyzed using ETABS, and then Construction Stage Analysis of each building model is done. A comparative study of Bending moments, axial forces, twisting moments and shear forces are carried out at every stage of the structural frame. These values are compared with linear static analysis and Construction Stage Analysis. From the values obtained correction factors are derived. From this method we can get results which has a maximum error of 2% and this proves that correction factor can be used as a substitute for sequential construction analysis

Perbandingan Analisis Struktur Gedung Laboratorium PGSD Universitas Samudra Metode Sistem Rangka Pemikul Momen Khusus Menggunakan ETABS dan BIM Tekla Struktural Designer

Indonesia is located on the fault line of the Eurasian and Indo-Australian plates which makes Indonesia prone to earthquakes. The structural design of the Special Moment Resisting Frame System (SRPMK) is required for reinforced concrete buildings in high earthquake-prone areas, it is hoped that using the SRPMK construction method can have a flexible structure. The purpose of this research is to discuss the comparison of test control of the Samudra University PGSD Laboratory Building with the Etabs application and the Tekla Structural Designer Application. The building structure under review is a reinforced concrete structure with 3 floors with a building length of 54 m, width of 18 m, and height of 16.8 m. The type of soil for the construction site is soft soil with earthquake design category D. Construction planning refers to SNI 1726 – 2019. The additional dead loads of floors and roofs are 0.672 and 0.710, the largest live loads are 7.18 kN/m², the earthquake loads with Ss and S1 are 0.68 and 0.34, the priority factor earthquake of 1.5 and a period of 20 seconds, the suction and compressive wind loads are -0.25 kN/m² and -0.41 kN /m². The results of structural analysis using the ETABS application and the Tekla Structural Designer application, the control values of the mass participation test, the fundamental natural vibration time, the base reaction, and the standard deviation between floors have met the requirements for earthquake-resistant building planning. The volume of concrete is 594.9 m³, the bone requirement for D22 is 3432.96 kg, D19 is 3605 4.89 kg, D16 is 26434.5 kg, D13 is 1774.72 kg, Ø12 is 6237.53 kg, Ø10 is 31599, 07 kg, Ø8 is 4589.31 kg

A Comparative Study of the Seismic Behaviour of G+20 Storey Symmetrical Buildings Constructed with Light Weight Concrete and Normal Weight Concrete

Abstract: Concrete with a density of less than 2000 kg/m^3 is considered lightweight concrete. Structural lightweight concrete (SLWC) is used to reduce the dead load of concrete structures. The purpose of this research is to examine and compare the results of SLWC made with scoria and normal weight concrete (NWC) and normal and light weight concrete(NAL) multistorey buildings. Multistorey buildings are often constructed of ordinary concrete, steel, and other materials. They are subjected to heavy loads, requiring heavy construction that may not be cost-effective. In this paper, a G+20multistorey plan symmetrical building is analysed using the response spectrum method with SLWC and NWC. Bending moment, shear force, storey shear, storey drift, and storey displacement are considered. The results of the NWC and SLWC and NAL buildings are compared . Concluding the research work that when comparing symmetrical plan area cases of normal concrete, light weight concrete and combination of normal and light weight concrete for all the result parameters, light weight concrete seems to be very efficient and most favorable case. Hence should be recommended when this type of construction procedure will be adopted, i.e. always use building with lightweight concrete

Static strength design of local thickened plate joints between multi-cell concrete-filled steel tubular column and steel beam

A new-type local thickened plate joint (LTPJ) between multi-cell concrete-filled steel tubular columns (CSTC) and steel beams is adopted in residential building structures. However, no available strength design method for such beam-column joints is reported. This paper presents the mechanical behavior and static strength design of such joints. The local thickened plates are adopted to replace the normal thickness plates of the CSTCs within the LTPJ region. The rectangular section and L-shaped section of the multi-cell CSTC are involved in the joint study, respectively. Firstly, a finite element model (FEM) of the LTPJ between CSTCs and steel beams is established, which is then adopted to investigate the mechanical behaviour and static load-bearing capacity of the LTPJ. Codirectional and inverse bending moments are applied on the beams on two opposite sides of the LTPJ to simulate lateral loads (arise from wind or earthquake) and dead gravity loads, respectively. It is revealed that the LTPJ experiences shear failure when subjected to lateral loads, whereas it succumbs to bending failure when under dead gravity loads. The shear-bearing capacity of the LTPJ results from the three-part contribution of the steel tube web, the steel tube flange, and the core concrete. The bending-bearing capacity of the LTPJ is determined by the plate normal tension-bearing capacity of the steel tubes, which is predicted by adopting the theory of yielding line and numerical fitting. Finally, the load-bearing capacities of LTPJ under bidirectional bending moment are investigated numerically, and accordingly, some strength design recommendations are proposed in practical application. To conclude, these results provide a method for accurately predicting the load-bearing capacity of the LTPJ subjected to lateral loads and gravity loads, which holds the potential to expand and enhance the application of LTPJs and CSTCs in the design of high-rise residential buildings.

Pengaruh Penggunaan Agregat Kasar dan Metode Pemanasan Styrofoam Terhadap Beton Ringan

Concrete is a construction material that is widely used in various types of construction. One of the disadvantages of concrete is that its specific gravity is quite high, thus giving a big dead load on the structure. An alternative to overcome this weakness is using lightweight concrete. Therefore, in this study, lightweight concrete will be made with heated styrofoam. The styrofoam used is expanded polystyrene (EPS) type with a grain size of 4-5 mm. Heating of styrofoam the was done at 100°C for 15 minutes and 100°C for 25 minutes. The objective of this study is to evaluate the compressive strength and specific gravity of lightweight concrete using heated styrofoam material with different heating methods and the use of coarse aggregate in the lightweight concrete. Test sample in this study used heated styrofoam as 100% coarse aggregate replacement and 75% coarse aggregate replacement, while the remaining 25% uses coarse aggregate with a maximum grain size of 19.05 mm. To improve workability, a superplasticizer of 0.9% by weight of cement was used. The results of compressive test showed that the optimum value of compressive strength testing of 11.24 MPa in lightweight concrete with coarse aggregate and heated styroforom with the heating for 25 minutes at a temperature of 100°C. The concrete strength was classified into lightweight concrete lightweight structure. The specific gravity of the concrete is 1.578.38 kg/m3, which was classified into lightweight concrete based on SNI 03-3449-2002.

Analisis Tidak Langsung Pada Desain Terhadap Stabilitas Struktur Gedung Baja

There are three methods of design for stability defined in AISC 360-16 Specification for Structural Steel Buildings, namely Direct Analysis Method (DAM), Effective-Length Method (ELM), and First-Order Analysis Method (FOM). DAM is the method that is featured by AISC. Based on DAM, Rafael Sabelli proposed another method called Indirect Analysis Method (IAM). IAM is a new method that has not generally been used, and also has not been included in the AISC Specification. This research is conducted in order to study IAM and compares the analysis results of IAM with those of DAM. Using a nonlinear structural analysis software, design and analysis were conducted for stability design of an eight-story building loaded with dead load, live load, and wind load. IAM provides a simple amplifier approach which is called B3 to address the member inelasticity, member imperfections, and uncertainty in member stiffness. From the study that has been conducted, the analysis results using IAM show close values with those of DAM, in terms of demand-to-capacity ratios, with IAM is more conservative than DAM. The use of IAM simplifies the design process without affecting the economy of the design.

Theoretical analysis and a parametric study on forced vibration of large statically deformed curved beam with rigid links and moving support

Forced vibration characteristics around large statically deformed configuration of curved beam system with rigid links and moving support are analyzed. In addition, the paper also investigates various parametric effects of height to span ratio and roller radius to height ratio coupled with support connection mechanism and profile shape, on dynamic characteristics of the curved beam system. The subject problem includes two interrelated problems: determining deformed configuration under static load and dynamic response of the loaded beam under harmonic excitation. The static problem is analyzed incrementally through the variational principle-based energy method in body-embedded curvilinear frame considering geometric nonlinearities due to combined bending-stretching and non-uniform initial curvature. In each incremental step, the nonlinear governing equation is solved iteratively, and kinematic constraints due to interactive deformation of the flexible curved beam with rigid links are imposed to obtain the global solution. Concerning the statically deformed configuration, governing equation for forced vibration is derived through Hamilton’s principle in curvilinear frame. Nonlinear effects caused by combined bending-stretching modes of vibration, non-uniform curvature, and lumped mass of the dead static load are considered. The set of inhomogeneous governing equations is solved through Broyden’s method. A direct substitution technique through successive relaxation is also employed to obtain an initial guess solution. Besides the forced vibration, free vibration analysis at static deformed configuration is also carried out for the completeness of the study. The theoretical model is validated through comparisons of loaded natural frequency results with finite element package. After the validation study, the effects of the mentioned geometric parameters on the dynamic response of the curved beam system are investigated and presented suitably. The physically insightful framework along with the parametric study may facilitate simulation and design of several practical structures involving moving support and rigid links subjected to continuous excitation around large statically deformed configurations.

Analytical assessment of the full-bridge response to the vertical live load: An algorithm for hybrid cable-stayed suspension bridges

Hybrid cable-stayed suspension bridges combine the advantages of cable-stayed and suspension bridges, mitigating their deficiencies. Due to its super spanning ability, this novel form of bridge enjoys a bright application prospect as a large-span structure. This study introduces an analytical algorithm to estimate the full-bridge response of a hybrid cable-stayed suspension bridge with a vertical uniformly distributed load applied to the main beam. This method is based on the assumption that all parameters, such as the geometric configuration, internal force distribution, and material properties, of the whole bridge under a dead load are known; then, it analyzes the full-bridge response under a live load. First, the minimum and independent basic unknown parameters of the full-bridge response are determined. Next, the governing equations are derived and solved based on the conservation of unstressed length of each section of cable, closure of span lengths and elevation difference in different spans, and conditions for stress balance of the main beam. Thus, the values of basic unknown parameters are obtained. Finally, they are substituted into the governing equations to estimate the full-bridge response, including each bridge component’s internal forces and deflections. The proposed analytical method involves no iterative procedures when dealing with nonlinear problems but only focuses on the bridge’s state with and without loading. The results are obtained directly by solving the equations, which have the advantages of high efficiency, simplicity, and clear physical meaning. Finally, the feasibility and effectiveness of the proposed method are verified by a finite-element-based calculation of an exemplary asymmetric cable-stayed suspension cooperation system bridge with a main span of 1400 m.

Influence of Steel and Polypropylene Fibers on the Structural Behavior of Sustainable Reinforced Lightweight Concrete Beams Made from Crushed Clay Bricks

Structural lightweight concrete is preferred over traditional concrete due to its ability to reduce the dead load, minimize the size of load-bearing structural members, and provide more economical solutions for foundation deteriorations. This research sheds light on sustainable lightweight concrete using waste crushed clay bricks (CCB) as a lightweight aggregate. To reduce micro-crack propagation of the developed concrete, two types of fiber were implemented and investigated. Steel fibers (SF) with amounts of 0.5% and 1.0% by volume of concrete, and polypropylene fibers (PPF) with amounts of 0.1% and 0.2% by volume of concrete, were employed. Five reinforced concrete beams were made and tested in order to precisely evaluate the structural behavior of the proposed lightweight CCB concrete. Additionally, ABAQUS software for nonlinear finite element analysis has been utilized to simulate the tested beams and compare the numerical model predictions with the experimental findings. The findings revealed that the addition of SF and PPF exhibited a notable influence on enhancing the mechanical characteristics of lightweight CCB concrete. Adding 0.2% PPF increased the ultimate load and deformation capacity at failure by approximately 16% and 24%, respectively. Furthermore, after 28 days, the addition of 0.5% and 1.0% SF enhanced the compressive strength by around 11.7% and 17.6%, respectively. Moreover, a significant level of consistency between the results obtained from the numerical model and the experimental findings was observed. In general, the use of SF and PPF in CCB concrete successfully produced high-quality lightweight concrete with interesting results for use in reinforced concrete beams.

Deformation of an elastic second gradient spherical body under equatorial line density of dead forces

We consider deformations of an elastic body having initially a spherical shape. Assumed deformation energy depends on the first and second gradient of displacements. We apply an equatorial line density of dead loads, that are forces per unit line length directed in radial direction and applied along the equator of the sphere. We restrict ourselves our analysis to the case of linearized second strain gradient isotropic elasticity (for which the more general energy was determined by Mindlin) with only one characteristic length. Differently to what happens in first gradient continua, i.e. in classic linear elasticity, we show that for the particular class second gradient continua considered here these forces do not determine infinite displacements in the direction of applied dead line forces. Instead, using a series method for the solution of the considered boundary-value problem, we demonstrate that the displacements are finite. So in the deformed configuration there is not the formation of an edge at the material points where the forces are applied. Further investigations are therefore needed for establishing if this elastic-regime edge formation is made possible: (I) either in the case of more general linear elastic constitutive equations or (II) only when large deformations are considered or (III) if non-elastic phenomena are involved.

Design Philosophy and Seismic Analysis of a Multi-Storey Building (B+G+10) with Flat Slabs in Seismic Zone II Using ETABS and SAFE Software

This journal paper presents the design philosophy and seismic analysis of a multi-storey building (B+G+10) with flat slabs located in Seismic Zone II. With the growing population and limited resources, vertical expansion has become a necessity. The economy's development has attracted foreign companies and innovative entrepreneurs, requiring the construction of high- end, safe workplaces. High-rise structures face challenges from wind and seismic loads, making proper design and analysis crucial for safety. The design philosophy emphasizes the use of reinforced concrete due to its versatility, durability, and fire resistance. Reinforced concrete, a composite material of concrete and steel reinforcement, ensures strain compatibility and load sharing between the materials. The paper discusses various design loads, including dead loads, live loads, wind loads, and earthquake (seismic) loads. Dead loads encompass the self-weight and permanent attachments to the structure, while live loads consider dynamic factors due to occupancy. Wind loads are assessed based on the local wind conditions, and earthquake loads are determined using seismic codes. Design principles for foundations, columns, and footings are addressed, with a focus on ensuring structural stability, safety, and uniform settlement. The depth of the foundation is calculated using Rankine's formula, considering soil properties. Column design is crucial, with short and long column classifications, and minimum eccentricity requirements are detailed. The seismic analysis of the building involves the use of ETABS and SAFE software, which enable engineers to model the structure and assess its response to seismic forces. The combination of a sound design philosophy and comprehensive seismic analysis tools ensures the building's ability to withstand various loads, thereby contributing to safety and sustainability.

ANALYSIS AND DESIGN OF BUILDING (B+G+10) WITH FLAT SLABS IN ZONE ‘II’ USING ETABS AND SAFE SOFTWARE

Structural Engineering is a Branch of civil engineering which deals in the determination of behaviour of structures in order to predict the responses of real structures like bridges, Buildings, etc. under the improvement of expected loading and external environment during the service life of the structure. Structural Engineers these days are up against the challenging task of striving for the most efficient and most economical design with accuracy in solution while guaranteeing the final design of a building is serviceable for its design lifetime. In reality it’s very difficult to predict with certainty how much damage a building will experience for a given level of ground motion, because there are number of factors that affect the behaviour of the structural systems. The objective is to emphasize on structural behaviour of a commercial building (basement + ground+10 stories) installed with flat slabs for Bangalore (Zone 2) pertaining to medium soil. The building model is designed and analysed using ETABS (Extended Three dimensional analysis of Building System) and SAFE. ETABS is the ultimate integrated software package for the structural analysis and design of buildings. SAFE is the ultimate tool for designing concrete floor and foundation systems. The lateral loads induced from wind and earthquakes in the design and analysis of building is considered. The dead loads are calculated as per IS 875(part 1)-1987, live load is taken as per IS 875(part 2)-1987, earthquake load has been taken as per IS 1893-2002(part 1) and wind load has been taken from IS 875 (part 3)1987. The manual calculations for the design of structural members were compared with the software results which were found to be satisfactory. All the design and detailing procedures for structural members were carried out as per the guidelines of Bureau of Indian Standard code books.

Comparative Study of Linear Static Analysis of G+10 Storey Building with and Without Shear Wall in ETABS

Planning, designing, and execution of high-raise building while taking into account the impact of lateral loads such as wind and seismic loads computation with or without shear wall technology in conventional mode is a crucial task for civil engineers. The lateral loads develop high lateral stresses and sway movement in structural members and need adequate stiffness to resist lateral forces along with sufficient strength against vertical gravity loads. In this case, civil engineers establish an effective system for construction of high raise building with the usage of shear wall system is high in-plane stiffness and torsional resistance. Present the authors are considered a G+10 storey commercial shopping mall with a central cut-out at Bhimavaram location which lies in seismic zone III as, per IS 1893(part 1): 2016. The load cases from IS 875 Part I (dead loads), Part II (imposed loads), and Part III (wind loads) are used to create the load combinations in accordance with IS 456: 2000. Two models, with and without shear wall system are taken for comparing the parameters like storey drift, storey displacement, stiffness, shear force, base shear, bending moment and center of rigidity by performing linear static seismic analysis and wind analysis for both models in ETABS software. The simulations concluded that Shear wall system is the efficient and economical way of resisting lateral loads in high rise or multistory buildings.

Seismic Analysis of RC Buildings with and without Shear Wall using NBC

Shear wall are not avoidable in construction of buildings. However, the behavior of structures with these Shear wall during earthquake needs to be studied. By taking adequate precautions, the main objective of Earthquake Engineering is to design and build a structure in such a way that the damage to the structure and its structural components during an earthquake is minimized. Constructions can suffer diverse damages when they are put under seismic excitations. Although for a same structural configuration, region& earthquake, damages in the system are neither equal nor homogenous. So, there are several factors for these like – Structural system, Earthquake characteristics, the quality of construction, soil of location and its maintenance that define the seismic behavior of the structure. Present study represents the behavior with shear wall and not with shear wall of building. In this present study ten storey building is considered. The building is modeled in ETABS-2018 with shear wall and not with shear wall considered for analysis. For analysis purpose various loads are considered like dead load, live load and earthquake load in X and Y-direction. Various loads combinations are considered according to NBC 105:2020. The main objective of this project is to find out which will have better seismic performance either building with shear wall or without shear wall. The analysis of model is done using dynamic method in ETABS software. Finally the results of seismic behavior of buildings are compared with respect to time period, base shear, storey shear, member forces, overturning moment, displacement, stiffness and drifts. Keyword: Shear wall, RC buildings, NBC, Displacements, Drift.

ASD and LRFD lateral load combinations: Comparison of required strength and reliability for design of structural steel

ASCE 7, Minimum Design Loads for Buildings and Other Structures, provides load combinations for both Load and Resistance Factor Design (LRFD) and for Allowable Stress Design (ASD), defining the required strength of structural members and connections. Similarly, the AISC Specification for Structural Steel Buildings provides resistance factors for LRFD and safety factors for ASD to be applied to the nominal strength for each limit state, permitting design using either method in conjunction with the corresponding load combinations in ASCE 7. Previous publications have demonstrated that similar designs (with similar levels of reliability) result from the application of LRFD and ASD for cases in which the governing load combination has live load as the principal load. This study presents comparison of ASD and LRFD demands, and corresponding reliability indices, from ASCE 7 lateral load combinations, determined with different proportions of dead, live, wind, and seismic load effects and a range of levels of second-order effects. The findings indicate that the generally accepted uniformity between the two design methods established for gravity load combinations does not always extend to lateral load combinations. For a range of conditions, design using ASD load combinations provides significantly lower reliability than using LRFD and does not meet the ASCE 7 reliability target.

COMPARISON ANALYSIS OF RAILWAY BRIDGE MODUL FOR “I” GIRDER TYPE AND “WARREN” TRUSS TYPE

The railway bridge in Indonesia, with a width of 1067 mm, was built in 1878, so that maintenance modules are needed to repair or to replace of construction modul at regular intervals. Implementation of maintenance and repairs refers to the Minister of Transportation Regulation No. 60 of 2012. Problems were encountered in the field at the BH182 Daop 2 railway bridge in Bandung due to lowering structural strength. Therefore, it was necessary to repair the bridge module with a new bridge design. The purpose of this study is to analyse and to calculate strength of the structure and to determine effectiveness of the use of construction materials on 2 alternative bridge construction selection with the type of “I" girder and the type of “Warren" Truss. Design implementation method used is to utilize Midas Civil Structure software. The loading used for railway bridges is grouped into three load groups, namely the girder's self-weight, additional dead load, and live load. Additional dead load analysed is line load including bearings, while for live load is trainset load based on loading requirements. From the results of calculations between the steel bridge “I" girder type height of 300 cm and the type of “Warren" Truss height of 600 cm, each span of 30 m showed that those were a function of the railway bridge. It would be more effective to use the type of “Warren” Truss structure that is quite able to withstand train traffic loads in accordance with applicable standards.

Large deformation of hyperelastic modified Timoshenko–Ehrenfest beams under different types of loads

In this paper, a nonlinear finite element formulation for a hyperelastic, modified Timoshenko–Ehrenfest beam with geometrical and material nonlinearities is developed for the first time. A new five-parameter beam element is introduced. The parameters contain displacement, values of difference vector and a through-the-thickness scalar value. Moreover, a new procedure is employed to apply the moment to the beam. The constitutive formulation is derived for Saint Venant–Kirchhoff (SVK) as well as the compressible neo-Hookean (n-H) hyperelastic model. The beam is subjected to different loads such as dead load, point and distributed loads, and follower pressure. To demonstrate the applicability of the formulations, several examples are solved. The results reveal that this formulation can capture the previous results reported in the literature. Furthermore, a comparative study is done between two hyperelastic models. It is demonstrated that in the case of large rotation of the beam, both Saint Venant–Kirchhoff and neo-Hookean models show the same behavior. However, in case of large deformation with large strains of the beam, the Saint Venant–Kirchhoff model behaves stiffer than the neo-Hookean hyperelastic model.