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Research Article
Performance of Simplified Damage-Based Concrete Models in Seismic Applications
Jesus Salazar Lopez,
Bernardo Garcia Ramirez,
Clayton Pettit*,
Carlos Cruz-Noguez
Issue:
Volume 12, Issue 4, August 2024
Pages:
95-107
Received:
19 June 2024
Accepted:
5 July 2024
Published:
15 July 2024
Abstract: Significant progress in the finite-element (FE) modeling at the member-level of reinforced-concrete (RC) structures under seismic excitation has been achieved in the past decades; however, reliable and accurate analysis models for full-scale 3D system-level RC structures validated with experimental data are scarce. As the development of a complete nonlinear model is expensive and time consuming, simpler models, typically elastic or lumped-plastic in nature, are employed in practice with additional provisions prescribed to account for nonlinear behavior. Depending on the assumptions made by the analyst, there may be substantial uncertainties related to the response of a complete structure. Capturing global failure modes is challenging, and the assessment of strength and ductility capacities may be inaccurate, resulting in potentially unsafe designs. The objective of this research is to assess the performance of simplified damage-based concrete biaxial models in analyzing and capturing the structural behavior of full-scale RC systems. Damage-based models for concrete require minor input from the analyst, facilitating their use in a design setting, while their explicit, non-conditional convergence formulations allow for non-iterative solutions. This results in damage-based models featuring efficient computational analysis while accounting for complex phenomena such as the capacity to account for stiffness recovery in reversal loading (crack closing) and permanent strains in the concrete. A comparison between analytical and experimental data at both the element- and system-levels is conducted, and a viable damage-based model is proposed for a full-scale structure analysis. The results of the study show that damage-based models are a viable alternative to developing efficient analysis models for elements and whole structures.
Abstract: Significant progress in the finite-element (FE) modeling at the member-level of reinforced-concrete (RC) structures under seismic excitation has been achieved in the past decades; however, reliable and accurate analysis models for full-scale 3D system-level RC structures validated with experimental data are scarce. As the development of a complete ...
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Research/Technical Note
Conformance and Performance Evaluation of Land Use Plan of Yirba Town
Daniel Lirebo Sokido*,
Addisu Sherbeza Woldemariam
Issue:
Volume 12, Issue 4, August 2024
Pages:
108-128
Received:
28 April 2024
Accepted:
15 May 2024
Published:
23 July 2024
Abstract: The purpose of the research is to examine the conformance and performance of land use plan of Yirba town. To get accurate and adequate information on the level of achievement of urban plan, primary and secondary data sources were used with respect to land use categories. Primary data sources such as land inventory and key informants interview were exhaustively employed. Land inventory was undertaken to have firsthand information on the existing situation of general as well as detail land use of the town. Key informants interview were conducted to gather data from experts Yirba municipality, and Sidama Region Urban planning Institute. Secondary data sources such as document reviews of basic plan and strategic Plan of Yirba town, urban development policy and other legal documents were used for investigation purpose. GIS, Microsoft office word, and excel were used to analyze the quantitative and qualitative data. The results of the analysis were presented in the form of maps, graph, chart, and tables. Descriptive and explanatory analysis research designs were employed. The results of analysis elucidates that conformance evaluation has vital contribution to avoid wastage of urban land and the best use of available space. The performance evaluation results make clear the overall achievement of urban plan for the stated town is low. Even though it is overlooked, the conformance evaluation that is conducted prior to the approval of the proposed plan and during implementation is crucial for preventing the wastage of urban land and significantly helps for proper implementation. A full-fledged performance evaluation is recommended before the commencement of new urban plan for the town. Conducting such performance evaluation helps identify the level of success or failure, and the gaps of the prior plan. Since action plans and phasing plans are tools for implementation, they must be developed in tandem with land use plans for the proper execution of urban plans. Urban planning is regarded to be a collaborative field. It necessitates cooperation of numerous teams or experts during the planning and execution stages.
Abstract: The purpose of the research is to examine the conformance and performance of land use plan of Yirba town. To get accurate and adequate information on the level of achievement of urban plan, primary and secondary data sources were used with respect to land use categories. Primary data sources such as land inventory and key informants interview were ...
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Research Article
Result Comparison of Spectral Matching Between Seismomatch and Specmatch Computer Program
Hanindya Kusuma Artati,
Lalu Makrup*,
Jafar,
Pranowo
Issue:
Volume 12, Issue 4, August 2024
Pages:
129-138
Received:
15 July 2024
Accepted:
6 August 2024
Published:
20 August 2024
DOI:
10.11648/j.ajce.20241204.13
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Abstract: The earthquake ground motion, or acceleration time history, caused by an earthquake event, is an earthquake acceleration wave that can be utilized as a basis to design earthquake-resistant civil engineering buildings. The earthquake acceleration time history is needed as a basis to determine the earthquake loading for the building structure design. A time history can be developed from recorded data using spectral matching software. In this process, the response spectra of the recorded time history are matched to a specific target spectrum. The target spectrum is developed based on the Indonesian National Standard known as SNI 2012 (SNI code). The response spectra derived from this standard are referred to as the design response spectrum. These response spectra adopted by the SNI code are based on the ASCE code from the US. Two spectral matching software programs, namely Seismomatch and Specmatch, are employed for this purpose. In this study, both of software programs are utilized to match the response spectra of a time history to a predefined response spectrum. The results of the matching process indicate that Seismomatch does not produce a satisfactory match between the response spectra of the time history and the target spectrum, whereas Specmatch provides a matching result where the response spectra of the time history nearly perfectly align with the target spectrum.
Abstract: The earthquake ground motion, or acceleration time history, caused by an earthquake event, is an earthquake acceleration wave that can be utilized as a basis to design earthquake-resistant civil engineering buildings. The earthquake acceleration time history is needed as a basis to determine the earthquake loading for the building structure design....
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Research Article
Addition of Ground Zeolite to Improve the Flowability and Cohesiveness of Mortar
Jiajian Chen*,
Weiliang Xie,
Tianxiang Chen
Issue:
Volume 12, Issue 4, August 2024
Pages:
139-143
Received:
22 July 2024
Accepted:
20 August 2024
Published:
27 August 2024
Abstract: Packing density if of cardinal importantce in the performance of cement-based materials. Theoretically, ground zeolite (GZ), a cementitious material that is finer than cement and coarser than condensed silica fume (CSF), is able to fill the voids between the cement particles in mortar for performance improvement without excessively high specific surface area. In order to evaluate the effects of GZ on flowability and cohesiveness, a total of 15 mortar mixes with different GZ contents and different cementitious materials/aggregate ratios at the same water/cementitious materials ratio were produced for flowability, cohesiveness and strength measurement. Results indicated that adding GZ as no more than 5% cement replacement would increase the flowability and strength, but further addition of GZ to more than 5% decreased the flowability, cohesiveness and strength. The experimental results are in general agreement with the findings from the literatures. Adding GZ tas no more than 5% cement replacement improve both the flowability and cohesiveness at equal-strength basis, further addition of GZ upon 5% improved the concurrent flowability and strength performance when the strength requirement is low, but impaired the concurrent cohesiveness and strength performance. It can be concluded that 5% is optimum GZ addition content in the viewpoint of flowability and cohesiveness performance of mortar.
Abstract: Packing density if of cardinal importantce in the performance of cement-based materials. Theoretically, ground zeolite (GZ), a cementitious material that is finer than cement and coarser than condensed silica fume (CSF), is able to fill the voids between the cement particles in mortar for performance improvement without excessively high specific su...
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Research Article
A Literature Study of Emergency Material Dispatch Models and Optimisation in the Context of Natural Disasters
Zhou Ruoqi*,
Duan Manzhen
Issue:
Volume 12, Issue 4, August 2024
Pages:
144-152
Received:
7 August 2024
Accepted:
21 August 2024
Published:
30 August 2024
Abstract: The recurrent occurrence of natural disasters has brought into sharp focus the urgent need for the expedient distribution of emergency materials. In the aftermath of a disaster, the swift and precise distribution of essential emergency supplies is of the utmost importance in ensuring the basic survival needs of the affected population are met, minimising the impact of the disaster and maintaining social stability. In order to provide a comprehensive overview of the research progress in the field of emergency supplies dispatching after natural disasters, we employ the knowledge graph analysis software VOSviewer to investigate the optimisation issues pertaining to the emergency supplies dispatching model, taking into account the inherent uncertainty, from a multi-objective standpoint and across a range of algorithms. A total of 375 literature sources were included in the China Knowledge Network database for review. The research objectives, methods and conclusions of the representative literature on hot spots at home and abroad were subjected to analysis. The review examines the research objectives, methodologies and conclusions of the most prominent literature on the subject, both domestic and international, and analyses the current status of research on the scheduling of emergency materials in the context of natural disasters. By synthesising these findings, we aim to identify gaps in existing research and suggest directions for future endeavours to promote a more resilient and effective emergency management system that can respond rapidly to the ever-changing needs of disaster-affected communities.
Abstract: The recurrent occurrence of natural disasters has brought into sharp focus the urgent need for the expedient distribution of emergency materials. In the aftermath of a disaster, the swift and precise distribution of essential emergency supplies is of the utmost importance in ensuring the basic survival needs of the affected population are met, mini...
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