Reinforced Concrete Analysis In Higher Evaluation System Technology Research Articles

Analytical Performance Assessment of Deteriorated Prestressed Concrete Beams

In this paper, a new approach is developed to numerically evaluate the structural performance of deteriorated prestressed concrete beams using the finite element analysis application RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology). A prestressing steel element was modified to represent the interaction between deteriorated concrete and prestressing steel. Considering the corrosion effects—as shown by the reduction of the prestressing steel section and loss of bond—a nonlinear material model was proposed for deteriorated prestressed concrete behavior. The modified damage index is intended to provide a numerical method for quantifying the structural performance of deteriorated prestressed concrete beams. The analytical procedure developed for the performance evaluation of deteriorated beams was validated by comparison with the credible test results, thereby enabling a more reliable and rational prestressed concrete beams design process.

Novel Plastic Hinge Element for Seismic Performance Assessment of RC Bridge Columns with Lap Splices

This paper presents a nonlinear analysis procedure for evaluating the seismic performance of reinforced concrete (RC) bridge columns with lap splices using a novel plastic hinge element considering shear deformation. To accurately assess the inelastic behavior of RC bridge columns, reliable three-dimensional (3D) constitutive models are required. However, developing a 3D nonlinear material model is difficult and computationally intensive. In this study, to address these issues, a new plastic hinge element considering shear deformation for RC bridge columns is developed. The new plastic hinge element is based on the Timoshenko beam theory and utilizes two-noded zero length element with six degrees of freedom. The finite element model was implemented in a computer program named Reinforced Concrete Analysis in Higher Evaluation System Technology (RCAHEST) developed by the authors. The developed plastic hinge element for seismic performance assessment of RC bridge columns with lap splices was validated through comparison of the numerical and experimental results.

Seismic Performance Assessment of Deteriorated Two-Span Reinforced Concrete Bridges

This paper presents a nonlinear analysis procedure for the seismic performance assessment of deteriorated reinforced concrete bridges using a modified damage index. A finite-element analysis program, RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), is used to analyze deteriorated two-span simply supported reinforced concrete bridges. The new nonlinear material models for deteriorated reinforced concrete behaviors were proposed, considering corrosion effects as shown in a reduction in reinforcement section and bond strength. A modified damage index aims to quantify the seismic performance level in deteriorated reinforced concrete bridges. Several parameters of two-span simply supported deteriorated reinforced concrete bridge have been studied to determine the seismic performance levels. The newly developed analytical method for assessing the seismic performance of deteriorated reinforced concrete bridges is verified by comparison with the experimental and analytical parameter results.

Seismic performance assessment of RC columns with interlocking hoops

The aim of this study is to analytically assess the seismic performance of reinforced concrete (RC) columns with interlocking hoops using a novel damage index, and to provide data for developing next generation seismic design criteria. Interlocking hoops are used in rectangular or non-circular columns, the splices shall be located in the column interior. Seismic performance of RC columns is controlled by the level of confinement provided by transverse steel. Interlocking hoops are commonly used in RC columns because they can provide more effective confinement than rectangular hoops. Three RC interlocking columns were tested under a constant axial load and a cyclically reversed horizontal load. A computer program, Reinforced Concrete Analysis in Higher Evaluation System Technology (RCAHEST), is used to analyze RC structures. Novel damage indices aim to provide a means of numerically quantifying the performance level in RC columns with interlocking hoops sustained under earthquake loading. The proposed numerical method for the seismic performance assessment of interlocking columns is verified by comparison with the experimental results.

Seismic performance assessment of reinforced concrete wall piers for out-of-plane seismic loads

The purpose of this study is to assess the seismic performance of reinforced concrete wall piers for out-of-plane seismic loads, and to provide a method for developing a new evaluation procedure. A non-linear finite element analysis program, RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), is used to carry out all the seismic analyses of reinforced concrete wall piers. The wall piers were modelled using a combination of reinforced concrete shell elements and newly developed interface elements with six degrees of freedom. The reinforced concrete shell interface element is used to account for local discontinuous deformations at the boundary plane caused by abrupt changes in stiffness where members with different thickness are connected. Novel damage indices were modified to provide a means of quantifying numerically the seismic performance level in wall piers sustained under earthquake loading. Six reinforced concrete wall pier specimens were loaded in the weak direction under cyclic loading. The failure mode of the wall piers was either compression failure of the concrete or fracture of the longitudinal reinforcing bars due to low-cycle fatigue. The proposed numerical method for the seismic performance assessment of reinforced concrete wall piers for out-of-plane seismic loads is verified by comparison with the experimental and analytical results.

Analytical seismic performance assessment of hollow reinforced-concrete bridge columns

The aim of this study is to analytically assess the seismic performance of hollow reinforced-concrete bridge columns using a novel damage index, and to provide data for developing next generation design criteria. Hollow reinforced-concrete bridge columns have been used in the past in place of their solid counterparts in the construction of bridges. These hollow columns have several benefits over solid columns, including the reduction of vertical load applied to the foundation as well as the reduction of seismic mass. Two circular and two rectangular hollow reinforced-concrete bridge columns were tested under a constant axial load and a cyclically reversed horizontal load. A computer program, RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), is used to analyse reinforced-concrete structures. Novel damage indices aim to provide a means of quantifying numerically the performance level in cast-in-place and precast hollow reinforced-concrete bridge columns sustained under earthquake loading. The proposed numerical method for the seismic performance assessment of hollow reinforced-concrete bridge columns is verified by comparison with the experimental results.

Hollow bridge columns with triangular confining reinforcement

The purpose of this study is to assess the structural performance of hollow bridge columns with triangular confining reinforcement. The proposed triangular reinforcement details were equal to the conventional reinforcement details in terms of required structural performance. The triangular confining reinforcement is also economically feasible and rational, and facilitate shorter construction periods. Three hollow cast-in-situ concrete and three precast concrete bridge columns were tested. The behavior of the hollow columns is discussed in terms of their lateral load-drift relationship, cumulative dissipated energy, and lateral load-strain curves. The nonlinear finite element analysis program RCAHEST (reinforced concrete analysis in higher evaluation system technology) was used to analyze hollow bridge columns, and adopted a modified joint element for the precast concrete bridge columns. The results showed that the proposed innovative reinforcement details were superior to the conventional reinforcement details, in terms of the required structural performance.

Performance assessment of novel hollow and solid RC columns using simulation of shaking table test

The purpose of this study was to investigate the seismic performance of novel hollow and solid reinforced-concrete (RC) columns with triangular reinforcement details when subjected to impulsive near-fault ground motions. The results of numerical simulations of shaking table tests on six hollow columns and six solid columns are presented. The developed reinforcement details are shown to be economically feasible and rational, and they facilitate shorter construction periods. The use of a sophisticated non-linear finite-element analysis program enhanced the accuracy and objectivity of the assessment process. The computer program RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology) was used to analyse the RC structures. The equations of motion were solved by numerical integration using the Hilber–Hughes–Taylor algorithm. The numerical method used gave a realistic prediction of seismic performance throughout the input ground motions for several column specimens investigated. As a result, the developed triangular reinforcement details were considered to be superior to existing reinforcement details in terms of the required seismic performance. Such an analysis to study the seismic response of novel hollow and solid RC columns should lead to realistic and safe design.

Hollow precast segmental prestressed concrete bridge columns with a shear resistant connecting element

The purpose of this study was to investigate the performance of hollow precast segmental prestressed concrete (PSC) bridge columns with a shear resistant connecting element. A model of hollow precast segmental PSC bridge columns was tested under a constant axial load and a cyclically reversed horizontal load. The computer program, RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology) was used. Non-dimensional P-M interaction diagrams were developed to predict the design resistance of precast segmental PSC bridge columns. Among the numerous parameters, this study concentrates on concrete compressive strength, prestressing reinforcement ratio, effective prestress, diameter of circle passing through tendon centerlines-to-outside diameter of section ratio (Ds/Do) and inside diameter of section-to-outside diameter of section ratio (Di/Do). This study documents the testing of hollow precast segmental PSC bridge columns under cyclic loading and presents conclusions and design recommendations based on the experimental and analytical findings.

Performance Assessment of Hollow Precast Segmental Bridge Columns with Reinforcement Details for Material Quantity Reduction

This study investigates the performance of hollow precast segmental bridge columns with reinforcement details for material quantity reduction. The proposed triangular reinforcement details are economically feasible and rational, and facilitate shorter construction periods. The precast segmental bridge columns provides an alternative to current cast-in-place systems. We tested a model of hollow precast segmental bridge columns under a constant axial load and a quasi-static, cyclically reversed horizontal load. We used a computer program, Reinforced Concrete Analysis in Higher Evaluation System Technology (RCAHEST), for analysis of reinforced concrete structures. The used numerical method gives a realistic prediction of performance throughout the loading cycles for hollow precast segmental bridge column specimens investigated. As a result, proposed reinforcement details for material quantity reduction was equal to existing reinforcement details in terms of required performance.

New Hollow RC Bridge Piers with Triangular Reinforcement Details

This study investigates the seismic performance of new hollow reinforced concrete (RC) bridge piers with triangular reinforcement details. The developed triangular reinforcement details are economically feasible and rational, and facilitate shorter construction periods. We tested a model of new hollow RC bridge piers with triangular reinforcement details under a constant axial load and a quasi-static, cyclically reversed horizontal load. We used a computer program, Reinforced Concrete Analysis in Higher Evaluation System Technology (RCAHEST), for analysis of RC structures. The used numerical method gives a realistic prediction of seismic performance throughout the loading cycles for several hollow pier specimens investigated. As a result, developed triangular reinforcement details for material quantity reduction was equal to existing reinforcement details in terms of required performance.

Performance assessment of advanced hollow RC bridge column sections

This study investigates the performance of advanced hollow reinforced concrete (RC) bridge column sections with triangular reinforcement details. Hollow column sections are based on economic considerations of cost savings associated with reduced material and design moments, as against increased construction complexity, and hence increased labor costs. The proposed innovative reinforcement details are economically feasible and rational, and facilitate shorter construction periods. We tested a model of advanced hollow column sections under quasi-static monotonic loading. The results showed that the proposed triangular reinforcement details were equal to the existing reinforcement details, in terms of the required performance. We used a computer program, Reinforced Concrete Analysis in Higher Evaluation System Technology (RCAHEST), for analysis of the RC structures; and adopted a modified lateral confining effect model for the advanced hollow bridge column sections. Our study documents the testing of hollow RC bridge column sections with innovative reinforcement details, and presents conclusions based on the experimental and analytical findings. Additional full-scale experimental research is needed to refine and confirm the design details, especially for the actual detailing employed in the field.

New Hollow RC Bridge Pier Sections with Triangular Reinforcement Details: II. Parametric Study

The purpose of this study is to investigate the behavior characteristics of new hollow reinforced concrete (RC) bridge pier sections with triangular reinforcement details and to provide the details and reference data. Among the numerous parameters, this study concentrates on the shape of the section, the reinforcement details and the spacing of the transverse reinforcement. Additional eight column section specimens were tested under quasi-static monotonic loading. In this study, the computer program, named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), was used. A innovative confining effect model was adopted for new hollow bridge pier sections. This study documents the testing of new hollow RC bridge pier sections with triangular reinforcement details and presents conclusions based on the experimental and analytical findings.

Structural performance assessment of deteriorated reinforced concrete bridge piers

The aim of this study is to assess the structural performance of deteriorated reinforced concrete bridge piers, and to provide method for developing improved evaluation method. For a deteriorated bridge piers, once the cover spalls off and bond between the reinforcement and concrete has been lost, compressed reinforcements are likely to buckle. By using a sophisticated nonlinear finite element analysis program, the accuracy and objectivity of the assessment process can be enhanced. A computer program, RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), is used to analyze reinforced concrete structures. Material nonlinearity is taken into account by comprising tensile, compressive and shear models of cracked concrete and a model of reinforcing steel. Advanced deteriorated material models are developed to predict behaviors of deteriorated reinforced concrete. The proposed numerical method for the structural performance assessment of deteriorated reinforced concrete bridge piers is verified by comparing it with reliable experimental results. Additionally, the studies and discussions presented in this investigation provide an insight into the key behavioral aspects of deteriorated reinforced concrete bridge piers.

Performance assessment of hollow RC bridge columns with triangular reinforcement details

The aim of this study was to assess the performance of hollow reinforced concrete (RC) bridge columns with triangular reinforcement details for materials quantity reduction and to provide data for developing improved design criteria. Hollow column sections are designed based on the economic considerations of the cost savings associated with reduced materials and design moments compared with increased construction complexity and hence increased labour costs. The proposed triangular reinforcement details are economically feasible and rational and facilitate shorter construction periods. Five hollow RC bridge columns were tested under a constant axial load and a cyclically reversed horizontal load. The effect of the proposed reinforcement details on the performance of hollow bridge columns was investigated. The computer program RCAHEST (Reinforced concrete analysis in higher evaluation system technology) was used to analyse RC structures. The proposed numerical method for the performance assessment of hollow RC bridge columns was verified by comparison with experimental results. As a result, the proposed reinforcement details were designed prior to the existing reinforcement details in terms of required performance. Additionally, the studies and discussions presented here provide insight into the key behavioural aspects of hollow RC bridge columns with triangular reinforcement details.

Performance assessment of precast concrete pier cap system

The purpose of this study was to investigate the performance of precast concrete pier cap system. The proposed precast pier cap provides an alternative to current cast-in-place systems, particularly for projects in which a reduced construction time is desired. Five large-scale pier cap specimens were constructed and tested under quasistatic monotonic loading. The computer program, RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology) was used for the analysis of reinforced concrete structures. A bonded tendon element is used based on the finite element method, and can represent the interaction between the tendon and concrete of a prestressed concrete member. A joint element is used in order to predict the inelastic behaviors of segmental joints with a shear key. This study documents the testing of the precast concrete pier cap system under monotonic loading and presents conclusions and design recommendations based on the experimental and analytical findings. Additional full-scale experimental research is needed to refine and confirm design details, especially for actual detailing employed in the field.

Performance assessment of hollow RC bridge column sections with reinforcement details for material quantity reduction

The purpose of this study was to investigate the performance of hollow reinforced concrete (RC) bridge column sections with reinforcement details for material quantity reduction. Hollow column sections are based on economic considerations of the cost savings associated with reduced material and design moments compared with increased construction complexity and hence increased labour costs. The proposed reinforcement details demonstrate economic feasibility and rationality, and facilitate shorter construction periods. Models of hollow column sections with reinforcement details for material quantity reduction were tested under quasi-static monotonic loading. The proposed reinforcement details for material quantity reduction were equal to the existing reinforcement details in terms of required performance. The computer program RCAHEST (Reinforced concrete analysis in higher evaluation system technology) was used for the analysis of RC structures. A modified lateral confining effect model was adopted for hollow bridge column sections. This study documents the testing of hollow RC bridge column sections with reinforcement details for material quantity reduction and presents conclusions based on the experimental and analytical findings. Additional full-scale experimental research is needed to refine and confirm design details, especially for the actual detailing employed in the field.

물량저감 철근상세를 갖는 중공 철근콘크리트 교각단면에 관한 매개변수 연구

The purpose of this study is to investigate the inelastic behavior of hollow reinforced concrete bridge column sections with reinforcement details for material quantity reduction and to provide the details and reference data. Among the numerous parameters, this study concentrates on the shape of the section, the reinforcement details, the diameter of the transverse reinforcement and loading types. Eighteen column section specimens were tested under quasi-static monotonic loading. In this study, the computer program RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology) was used. A modified lateral confining effect model was adopted for the hollow bridge column sections. This study documents the testing of hollow reinforced concrete bridge column sections with reinforcement details for material quantity reduction and presents conclusions based on the experimental and analytical findings.

Inelastic behaviour and ductility capacity of circular hollow reinforced concrete bridge piers under earthquake

The purpose of this study was to investigate the inelastic behaviour and ductility capacity of circular hollow reinforced concrete bridge piers based on various design parameters. The ultimate strength and ductility of these bridge piers varied with the amount and arrangement of lateral reinforcement, the ratio of the inside to outside diameter of the column sections, the axial load ratio and longitudinal steel percentage. A total of eight solid and hollow circular reinforced concrete bridge piers with these design variables was tested under a constant axial load and cyclically reversed horizontal load. A computer program, the RCAHEST (reinforced concrete analysis in higher evaluation system technology), was used to predict the inelastic behaviours of circular hollow reinforced concrete bridge piers. Also, the modified lateral confining effect model was adopted and incorporated into the structural element library for RCAHEST. The proposed numerical method for the inelastic behaviour and ductility capacity of circular hollow reinforced concrete bridge piers is verified by comparing the analytical results with test data developed by the authors.

Seismic Performance Assessment of Hollow Reinforced Concrete and Prestressed Concrete Bridge Columns

The aim of this study is to assess the seismic performance of hollow reinforced concrete and prestressed concrete bridge columns, and to provide data for developing improved seismic design criteria. By using a sophisticated nonlinear finite element analysis program, the accuracy and objectivity of the assessment process can be enhanced. A computer program, RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), is used to analyze reinforced concrete and prestressed concrete structures. Tensile, compressive and shear models of cracked concrete and models of reinforcing and prestressing steel were used to account for the material nonlinearity of reinforced concrete and prestressed concrete. The smeared crack approach was incorporated. The proposed numerical method for the seismic performance assessment of hollow reinforced concrete and prestressed concrete bridge columns is verified by comparing it with the reliable experimental results. Additionally, the studies and discussions presented in this investigation provide an insight into the key behavioral aspects of hollow reinforced concrete and prestressed concrete bridge columns.