Pub Date : 2023-02-21DOI: 10.1080/13287982.2023.2176972
Amirhesam Taghipour, J. Zakeri, M. Jahangiri, S. Mosayebi
ABSTRACT Full service without defects of railway bridges is more important than highway bridges because failure at a part of the bridge results in the blockage of the entire track and the stopping of the trains. In recent years, the problem of an over-height vehicle collision to the bridge superstructure has occurred more frequently. These collisions damage the bridge superstructure and affect the safety of the train causing many problems in railway transportation. In this study, first, a model of the concrete girder bridge was used to validate the effect of the collision load applied to the bottom of the concrete girder bridge. Then, the dynamic responses of the railway bridge simulated as concrete girders and bridge deck also track including rail, sleeper, and ballast are presented by using the finite element method. Finally, the different sensitivity analyses express that changing the bridge span length, and the value of collision loads affect the concrete girder lateral displacement at the contact area. The results show that the lateral displacements decrease with increasing the span length. Additionally, by increasing the collision forces due to increasing the velocity of the impacting object, the lateral displacement at the bottom of the girder reduces.
{"title":"Investigating the dynamic behaviour of a railway bridge subjected to over-height vehicle collision","authors":"Amirhesam Taghipour, J. Zakeri, M. Jahangiri, S. Mosayebi","doi":"10.1080/13287982.2023.2176972","DOIUrl":"https://doi.org/10.1080/13287982.2023.2176972","url":null,"abstract":"ABSTRACT Full service without defects of railway bridges is more important than highway bridges because failure at a part of the bridge results in the blockage of the entire track and the stopping of the trains. In recent years, the problem of an over-height vehicle collision to the bridge superstructure has occurred more frequently. These collisions damage the bridge superstructure and affect the safety of the train causing many problems in railway transportation. In this study, first, a model of the concrete girder bridge was used to validate the effect of the collision load applied to the bottom of the concrete girder bridge. Then, the dynamic responses of the railway bridge simulated as concrete girders and bridge deck also track including rail, sleeper, and ballast are presented by using the finite element method. Finally, the different sensitivity analyses express that changing the bridge span length, and the value of collision loads affect the concrete girder lateral displacement at the contact area. The results show that the lateral displacements decrease with increasing the span length. Additionally, by increasing the collision forces due to increasing the velocity of the impacting object, the lateral displacement at the bottom of the girder reduces.","PeriodicalId":45617,"journal":{"name":"Australian Journal of Structural Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85363663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-19DOI: 10.1080/13287982.2023.2176025
L. Haj Najafi, H. Rajabi
ABSTRACT This study investigates the effect of redundancy incorporation as static indeterminacy and possibility to utilise alternative load paths in design and seismic behaviour of steel truss bridge conveyors by conducting complementary reliability assessments. The results could be supportive in adjusting the degree of indeterminacy, especially for long structures, to convince the design goals. It is conceived that the design approach with lower indeterminacy donates to less structural weight in addition to a bit more fundamental period contributing to less earthquake-induced demands and easily controllable lateral drifts in the end reference points which are very crucial in view of connecting to the adjacent structures. On the other hand, providing more indeterminacy in conveyor design could bring about more ductility, nonlinear displacement and earthquake energy dissipation as well as closer nonlinear behavioural parameters to the amounts recommended by the design code. In reliability assessments by increasing the degree of indeterminacy, the failure probability is reduced which contributes to the design with higher reliability indexes and higher collapse safety margin and it is expected that the incorporation of redundancy effects would be more perceivable by providing models with more redundancy discrepancy.
{"title":"Reliability interpretation of redundancy on design and seismic behaviour of steel conveyors","authors":"L. Haj Najafi, H. Rajabi","doi":"10.1080/13287982.2023.2176025","DOIUrl":"https://doi.org/10.1080/13287982.2023.2176025","url":null,"abstract":"ABSTRACT This study investigates the effect of redundancy incorporation as static indeterminacy and possibility to utilise alternative load paths in design and seismic behaviour of steel truss bridge conveyors by conducting complementary reliability assessments. The results could be supportive in adjusting the degree of indeterminacy, especially for long structures, to convince the design goals. It is conceived that the design approach with lower indeterminacy donates to less structural weight in addition to a bit more fundamental period contributing to less earthquake-induced demands and easily controllable lateral drifts in the end reference points which are very crucial in view of connecting to the adjacent structures. On the other hand, providing more indeterminacy in conveyor design could bring about more ductility, nonlinear displacement and earthquake energy dissipation as well as closer nonlinear behavioural parameters to the amounts recommended by the design code. In reliability assessments by increasing the degree of indeterminacy, the failure probability is reduced which contributes to the design with higher reliability indexes and higher collapse safety margin and it is expected that the incorporation of redundancy effects would be more perceivable by providing models with more redundancy discrepancy.","PeriodicalId":45617,"journal":{"name":"Australian Journal of Structural Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90897306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-17DOI: 10.1080/13287982.2023.2173868
Andrea Isfeld, M. Stewart, M. Masia
ABSTRACT This paper focuses on a structural reliability-based assessment of clay brick unreinforced masonry (URM) walls subjected to uniformly distributed out-of-plane loads in one-way vertical bending. Stochastic models combining finite element analysis (FEA) and Monte Carlo simulations (MCS) are used to account for spatial variability of the flexural tensile bond strength when estimating the wall failure loads. The strength of URM walls is known to be influenced by the flexural tensile bond strength, which is subject to high spatial variability as batching, workmanship, and environmental exposure alter the strength of this bond. For this assessment, single skin walls have been considered with bond strength statistics seen in typical construction. The model error statistics available for similar walls are combined with the results of the spatial stochastic FEA and probabilistic load models to determine the reliability index corresponding to the Australian Standard for Masonry Structures AS 3700 design of members in vertical bending. It was found that existing levels of reliability exceed target reliabilities, and the capacity reduction factor can be increased from 0.60 to 0.65 for URM walls in one-way vertical bending while still providing an acceptable level of reliability. A sensitivity analysis showed this finding to be robust.
{"title":"Structural reliability and partial safety factor assessment of unreinforced masonry in vertical bending","authors":"Andrea Isfeld, M. Stewart, M. Masia","doi":"10.1080/13287982.2023.2173868","DOIUrl":"https://doi.org/10.1080/13287982.2023.2173868","url":null,"abstract":"ABSTRACT This paper focuses on a structural reliability-based assessment of clay brick unreinforced masonry (URM) walls subjected to uniformly distributed out-of-plane loads in one-way vertical bending. Stochastic models combining finite element analysis (FEA) and Monte Carlo simulations (MCS) are used to account for spatial variability of the flexural tensile bond strength when estimating the wall failure loads. The strength of URM walls is known to be influenced by the flexural tensile bond strength, which is subject to high spatial variability as batching, workmanship, and environmental exposure alter the strength of this bond. For this assessment, single skin walls have been considered with bond strength statistics seen in typical construction. The model error statistics available for similar walls are combined with the results of the spatial stochastic FEA and probabilistic load models to determine the reliability index corresponding to the Australian Standard for Masonry Structures AS 3700 design of members in vertical bending. It was found that existing levels of reliability exceed target reliabilities, and the capacity reduction factor can be increased from 0.60 to 0.65 for URM walls in one-way vertical bending while still providing an acceptable level of reliability. A sensitivity analysis showed this finding to be robust.","PeriodicalId":45617,"journal":{"name":"Australian Journal of Structural Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75756575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-17DOI: 10.1080/13287982.2023.2167644
B. Pushpakumara, Ttd Silva
ABSTRACT Steel slag is a melted by-product that mainly consists of calcium carbonate and metal oxides generated in the process of steel manufacturing. The main objectives of this study are to evaluate the effectiveness of steel slags as fine and coarse aggregates in concrete and to determine the optimum quantity of steel slag as fine and coarse aggregates to enhance the strength of concrete. Concrete cubes were cast by mixing steel slag as replacement (i.e. 0%, 10%, 25%, 50%, 75% and 100%) for fine and coarse aggregate, separately. Abrasion test, sieve analysis, water absorption and specific gravity test were conducted to determine the properties of raw materials. Unit weight, workability, compressive strength, splitting tensile strength and the possibility of corrosion were experimentally evaluated to determine the effectiveness of steel slag. It is found that 75% steel slag mixed concrete indicates improvements in compressive strength, splitting tensile strength and unit weight, respectively. Further, it was noted that steel slag aggregates were not corroded after conducting the Accelerated Corrosion Test Method (ACTM). Therefore, the use of steel slag as fine and coarse aggregates for concrete would improve the mechanical properties of concrete and reduce the adverse environmental impact.
{"title":"Evaluation of mechanical properties of steel slag as replacement for fine and coarse aggregate in concrete","authors":"B. Pushpakumara, Ttd Silva","doi":"10.1080/13287982.2023.2167644","DOIUrl":"https://doi.org/10.1080/13287982.2023.2167644","url":null,"abstract":"ABSTRACT Steel slag is a melted by-product that mainly consists of calcium carbonate and metal oxides generated in the process of steel manufacturing. The main objectives of this study are to evaluate the effectiveness of steel slags as fine and coarse aggregates in concrete and to determine the optimum quantity of steel slag as fine and coarse aggregates to enhance the strength of concrete. Concrete cubes were cast by mixing steel slag as replacement (i.e. 0%, 10%, 25%, 50%, 75% and 100%) for fine and coarse aggregate, separately. Abrasion test, sieve analysis, water absorption and specific gravity test were conducted to determine the properties of raw materials. Unit weight, workability, compressive strength, splitting tensile strength and the possibility of corrosion were experimentally evaluated to determine the effectiveness of steel slag. It is found that 75% steel slag mixed concrete indicates improvements in compressive strength, splitting tensile strength and unit weight, respectively. Further, it was noted that steel slag aggregates were not corroded after conducting the Accelerated Corrosion Test Method (ACTM). Therefore, the use of steel slag as fine and coarse aggregates for concrete would improve the mechanical properties of concrete and reduce the adverse environmental impact.","PeriodicalId":45617,"journal":{"name":"Australian Journal of Structural Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2023-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89657971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-12DOI: 10.1080/13287982.2022.2156167
M. Rakib, Abu Zakir Morshed
ABSTRACT A design guideline for shear strengthening of pre-cracked reinforced concrete (RC) beams using steel plates has been presented in this research by modifying the available shear capacity formulas. An experimental investigation was also carried out in order to validate the proposed guideline. Total five RC beams were fabricated, among which four beams were pre-cracked in shear by applying preloads. Two of the cracked beams were then strengthened with adhesive bonded steel plates while the rest two were strengthened with bolted steel plates. Variation was made in plate depth and bolt layers. The shear performance of the strengthened beams was evaluated by testing the beams to their ultimate capacity. Experimental results indicated that the shear capacity, ductility and stiffness of the pre-cracked beams increased significantly after strengthening with continuous steel plates. The shear capacity varied from 131% to 201% for strengthened beams compared to the control beam. Deeper plates offered better shear performance than the shallower plates. Modification of the existing formulas by introducing preload factors for estimating the shear capacity of the strengthened beams showed a good agreement with the experimental shear capacity.
{"title":"Shear strengthening design of pre-cracked reinforced concrete beams using bonded and bolted steel plates","authors":"M. Rakib, Abu Zakir Morshed","doi":"10.1080/13287982.2022.2156167","DOIUrl":"https://doi.org/10.1080/13287982.2022.2156167","url":null,"abstract":"ABSTRACT A design guideline for shear strengthening of pre-cracked reinforced concrete (RC) beams using steel plates has been presented in this research by modifying the available shear capacity formulas. An experimental investigation was also carried out in order to validate the proposed guideline. Total five RC beams were fabricated, among which four beams were pre-cracked in shear by applying preloads. Two of the cracked beams were then strengthened with adhesive bonded steel plates while the rest two were strengthened with bolted steel plates. Variation was made in plate depth and bolt layers. The shear performance of the strengthened beams was evaluated by testing the beams to their ultimate capacity. Experimental results indicated that the shear capacity, ductility and stiffness of the pre-cracked beams increased significantly after strengthening with continuous steel plates. The shear capacity varied from 131% to 201% for strengthened beams compared to the control beam. Deeper plates offered better shear performance than the shallower plates. Modification of the existing formulas by introducing preload factors for estimating the shear capacity of the strengthened beams showed a good agreement with the experimental shear capacity.","PeriodicalId":45617,"journal":{"name":"Australian Journal of Structural Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2022-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74286776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-27DOI: 10.1080/13287982.2022.2149975
Amir Pourtarki, H. Badri Ghavifekr, H. Afshin
ABSTRACT This paper uses the vibration-based damage detection method for structural health monitoring of a Railway Bridge. Hence, the bridge had been exactly modelled in finite element analysis software. Due to the elastomeric bridge bearing, direct calculating of the natural frequencies and extracting the mode shapes of the bridge is not suitable and effective. Therefore, a time-dependent transient analysis of the train movement on the bridge is done and then the vibrations of all truss cells during the train crossing period were extracted. Afterwards, the relevant data is transformed, which represents the natural frequencies of the bridge vibration and their amplitude at each point. In the following, the mode shapes of vibration and the distribution of vibration energy are calculated. Applying any artificial damages in the model, occurring changes in the natural frequencies, mode shapes, and the vibration energies of the modes, are examined. Consequently, detecting and locating damages in the structure has been done with acceptable accuracy. Finally, for validation of the results, an accelerometer is installed on the bridge truss in the middle part of the bridge to extract the acceleration of bridge vibration at the train crossing time interval. In the end, the results are compared and presented.
{"title":"Study on the dynamic behaviour of Bafgh-Bandar Abbas lane railway bridge for structural health monitoring purpose","authors":"Amir Pourtarki, H. Badri Ghavifekr, H. Afshin","doi":"10.1080/13287982.2022.2149975","DOIUrl":"https://doi.org/10.1080/13287982.2022.2149975","url":null,"abstract":"ABSTRACT This paper uses the vibration-based damage detection method for structural health monitoring of a Railway Bridge. Hence, the bridge had been exactly modelled in finite element analysis software. Due to the elastomeric bridge bearing, direct calculating of the natural frequencies and extracting the mode shapes of the bridge is not suitable and effective. Therefore, a time-dependent transient analysis of the train movement on the bridge is done and then the vibrations of all truss cells during the train crossing period were extracted. Afterwards, the relevant data is transformed, which represents the natural frequencies of the bridge vibration and their amplitude at each point. In the following, the mode shapes of vibration and the distribution of vibration energy are calculated. Applying any artificial damages in the model, occurring changes in the natural frequencies, mode shapes, and the vibration energies of the modes, are examined. Consequently, detecting and locating damages in the structure has been done with acceptable accuracy. Finally, for validation of the results, an accelerometer is installed on the bridge truss in the middle part of the bridge to extract the acceleration of bridge vibration at the train crossing time interval. In the end, the results are compared and presented.","PeriodicalId":45617,"journal":{"name":"Australian Journal of Structural Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2022-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90066601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-25DOI: 10.1080/13287982.2022.2149914
Hrishikesh N. Shedge, Manoj Kumar
ABSTRACT The substructure of an integral abutment bridge is designed to accommodate the lateral demand induced by the expansion and contraction of the bridge deck. The assembly of H-piles oriented about their weak axis of bending and aligned in a single row with a rigid connection to the abutment is most preferred for supporting the integral abutment bridges. The weak axis orientation of H-pile allows for higher displacement capacity, thus accommodating the cyclic thermal demand induced by a superstructure. The hysteretic response of H-piles is suggestive of the early onset of the plastic hinge formation, which helps in accommodating the cyclic demand. The H-piles in the integral abutment bridge experience low cycle fatigue induced by cyclic thermal variations, resulting in the buckling of flanges at the critical zone. This study assesses the impact of perforation made on H-pile flanges at the critical buckling zone. In this study, six unique geometries of perforations are modelled and analysed using combined nonlinear kinematic and isotropic hardening formulation. The hysteretic response of the perforated H-pile models has been compared with an unperforated model to assess the proposed perforation geometry's impact on the H-pile's hysteretic response.
{"title":"Response of perforated H-pile subjected to coupled lateral displacement history and axial loading","authors":"Hrishikesh N. Shedge, Manoj Kumar","doi":"10.1080/13287982.2022.2149914","DOIUrl":"https://doi.org/10.1080/13287982.2022.2149914","url":null,"abstract":"ABSTRACT The substructure of an integral abutment bridge is designed to accommodate the lateral demand induced by the expansion and contraction of the bridge deck. The assembly of H-piles oriented about their weak axis of bending and aligned in a single row with a rigid connection to the abutment is most preferred for supporting the integral abutment bridges. The weak axis orientation of H-pile allows for higher displacement capacity, thus accommodating the cyclic thermal demand induced by a superstructure. The hysteretic response of H-piles is suggestive of the early onset of the plastic hinge formation, which helps in accommodating the cyclic demand. The H-piles in the integral abutment bridge experience low cycle fatigue induced by cyclic thermal variations, resulting in the buckling of flanges at the critical zone. This study assesses the impact of perforation made on H-pile flanges at the critical buckling zone. In this study, six unique geometries of perforations are modelled and analysed using combined nonlinear kinematic and isotropic hardening formulation. The hysteretic response of the perforated H-pile models has been compared with an unperforated model to assess the proposed perforation geometry's impact on the H-pile's hysteretic response.","PeriodicalId":45617,"journal":{"name":"Australian Journal of Structural Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2022-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81903510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-24DOI: 10.1080/13287982.2022.2149977
M. Obeydi, Iman Mohammadpoor Baltork, M. Zeynalian
ABSTRACT In this paper, cold-formed steel C-shaped connectors, as one of the most commonly used components in steel wall/framing systems, were investigated under the pull-out failure modes using a detailed numerical study. Finite element models were validated using the data obtained from an experimental program; and the results were compared with the current design equations. Finally, a new pull-out strength equation was proposed based on the critical parameters affecting the behaviour of C-shaped connectors. In addition, initial bending stiffness of C-shaped connectors was studied using a simplified analytical approach; and the results obtained from the proposed new stiffness equation were compared with the initial slope of experimental and numerical force-displacement curves. These comparisons confirm the accuracy of the new strength and stiffness equations in order to apply to the analytical methods such as component-based method in future works.
{"title":"Numerical study on the stiffness and ultimate strength of cold-formed steel C-shaped connectors under pull-out failure","authors":"M. Obeydi, Iman Mohammadpoor Baltork, M. Zeynalian","doi":"10.1080/13287982.2022.2149977","DOIUrl":"https://doi.org/10.1080/13287982.2022.2149977","url":null,"abstract":"ABSTRACT In this paper, cold-formed steel C-shaped connectors, as one of the most commonly used components in steel wall/framing systems, were investigated under the pull-out failure modes using a detailed numerical study. Finite element models were validated using the data obtained from an experimental program; and the results were compared with the current design equations. Finally, a new pull-out strength equation was proposed based on the critical parameters affecting the behaviour of C-shaped connectors. In addition, initial bending stiffness of C-shaped connectors was studied using a simplified analytical approach; and the results obtained from the proposed new stiffness equation were compared with the initial slope of experimental and numerical force-displacement curves. These comparisons confirm the accuracy of the new strength and stiffness equations in order to apply to the analytical methods such as component-based method in future works.","PeriodicalId":45617,"journal":{"name":"Australian Journal of Structural Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2022-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89050941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-26DOI: 10.1080/13287982.2022.2133721
Ali Siddique, Tahir Mehmood, S. Qazi, Shahzad Khan, Adnan Nawaz, R. F. Tufail
ABSTRACT Pakistan’s unique geographical location has made it seismically vulnerable. Owing to this, recent earthquakes have revealed the susceptibility of the existing reinforced concrete (RC) buildings in Pakistan. This has raised concerns about the structural performance of RC buildings because most mid-rise RC buildings in Pakistan have shear wall lateral force resisting systems. In this study, a survey of existing mid-rise RC buildings in Pakistan's capital territory is used to develop a database of existing RC shear walls. By using this database, this research aims to provide a seismic performance assessment of existing RC shear walls to determine their deficiencies and provide necessary experimental data for retrofitting. Two RC shear wall specimens SW1 and SW2, representing the characteristics of existing RC shear walls are tested under quasi-static loading. The seismic response of the existing RC mid-rise walls is assessed through the mode of failure, hysteretic behavior, energy dissipation, flexure and shear stiffness, and curvature distribution. The findings reveal that the existing mid-rise RC walls in the region did not satisfy the performance criteria recommended by different seismic codes. Hence a comprehensive retrofitting strategy with building code compliance are prerequisites to avoid infrastructural and economic losses due to seismic activity.
{"title":"Seismic performance evaluation of code compliant and non-compliant RC walls","authors":"Ali Siddique, Tahir Mehmood, S. Qazi, Shahzad Khan, Adnan Nawaz, R. F. Tufail","doi":"10.1080/13287982.2022.2133721","DOIUrl":"https://doi.org/10.1080/13287982.2022.2133721","url":null,"abstract":"ABSTRACT Pakistan’s unique geographical location has made it seismically vulnerable. Owing to this, recent earthquakes have revealed the susceptibility of the existing reinforced concrete (RC) buildings in Pakistan. This has raised concerns about the structural performance of RC buildings because most mid-rise RC buildings in Pakistan have shear wall lateral force resisting systems. In this study, a survey of existing mid-rise RC buildings in Pakistan's capital territory is used to develop a database of existing RC shear walls. By using this database, this research aims to provide a seismic performance assessment of existing RC shear walls to determine their deficiencies and provide necessary experimental data for retrofitting. Two RC shear wall specimens SW1 and SW2, representing the characteristics of existing RC shear walls are tested under quasi-static loading. The seismic response of the existing RC mid-rise walls is assessed through the mode of failure, hysteretic behavior, energy dissipation, flexure and shear stiffness, and curvature distribution. The findings reveal that the existing mid-rise RC walls in the region did not satisfy the performance criteria recommended by different seismic codes. Hence a comprehensive retrofitting strategy with building code compliance are prerequisites to avoid infrastructural and economic losses due to seismic activity.","PeriodicalId":45617,"journal":{"name":"Australian Journal of Structural Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2022-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80086986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-19DOI: 10.1080/13287982.2022.2134354
Khaled Ahmat, Samer M. Barakat, S. Altoubat, Mohamad Alhalabi
ABSTRACT Following the ACI 318 design code and to control deflections, structural engineers must adhere to minimum thickness requirements for reinforced concrete (RC) slabs. However, these requirements do not account for various influencing variables such as span length, aspect ratio and applied live load. This paper assesses the adequacy of the ACI 318 minimum thickness requirements for two-way RC slabs through a probabilistic approach using Monte Carlo simulation (MCS). The probability distribution of the span-to-depth ratio (SDR) was fitted to the Burr distribution, and the goodness-of-fit test was applied to assess the fitting. Then, the effect of span length, aspect ratio, and live load on the maximum allowable SDR was evaluated, considering all material properties and applied loads as random variables. The analyses have shown a high correlation between the studied variables and the SDR. Therefore, multiple regression analysis was carried out, and four prediction models were proposed to conservatively predict the SDR for two-way slabs. The accuracy of the prediction models was statistically tested by comparing calculated to predicted SDR values, and a 10% maximum relative error was exhibited. The proposed prediction models were accurate for all practical ranges of span length, aspect ratio and live load in two-way slabs.
{"title":"Probabilistic assessment of ACI 318 minimum thickness requirements for two-way slabs","authors":"Khaled Ahmat, Samer M. Barakat, S. Altoubat, Mohamad Alhalabi","doi":"10.1080/13287982.2022.2134354","DOIUrl":"https://doi.org/10.1080/13287982.2022.2134354","url":null,"abstract":"ABSTRACT Following the ACI 318 design code and to control deflections, structural engineers must adhere to minimum thickness requirements for reinforced concrete (RC) slabs. However, these requirements do not account for various influencing variables such as span length, aspect ratio and applied live load. This paper assesses the adequacy of the ACI 318 minimum thickness requirements for two-way RC slabs through a probabilistic approach using Monte Carlo simulation (MCS). The probability distribution of the span-to-depth ratio (SDR) was fitted to the Burr distribution, and the goodness-of-fit test was applied to assess the fitting. Then, the effect of span length, aspect ratio, and live load on the maximum allowable SDR was evaluated, considering all material properties and applied loads as random variables. The analyses have shown a high correlation between the studied variables and the SDR. Therefore, multiple regression analysis was carried out, and four prediction models were proposed to conservatively predict the SDR for two-way slabs. The accuracy of the prediction models was statistically tested by comparing calculated to predicted SDR values, and a 10% maximum relative error was exhibited. The proposed prediction models were accurate for all practical ranges of span length, aspect ratio and live load in two-way slabs.","PeriodicalId":45617,"journal":{"name":"Australian Journal of Structural Engineering","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2022-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89360305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：