Sarehati Umar

Dr. Sarehati Umar

Universiti Teknologi Malaysia, Johor Bahru, Johor, Malaysia
orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 February 2018 in Measurement
Verified
Journal Article
Closed access
SUSarehati Umar
Sarehati Umar
NBNorhisham Bakhary
Norhisham Bakhary
AAA.R.Z. Abidin
A.R.Z. Abidin

18 May 2022 in Applied Sciences
Verified
Journal Article
Open access
PDF file
AAAbubakar Sharif Auwalu
Abubakar Sharif Auwalu
NNNorhazilan Md Noor
Norhazilan Md Noor
MSMOHAMAD SHAZWAN SHAZWAN BIN AHMAD SHAH AHMAD SHAH
MOHAMAD SHAZWAN SHAZWAN BIN AHMAD SHAH AHMAD SHAH
SUSarehati Umar
Sarehati Umar
mugahed amranmugahed amran
mugahed amran
Roman FediukRoman Fediuk
Roman Fediuk
People need durable shelters for living safely due to devastation caused by flooding in some areas, and it is not easy to mitigate the frequency and intensity of the flooding. Therefore, in this research, an industrialized building system (IBS) has been proposed as one of the best solutions. However, most of the existing IBSs were not designed and tested for resisting a sudden horizontal impact. Furthermore, the joints of some IBSs would likely be vulnerable to failure when subjected to a horizontal impact. There is a need to develop a bolt-connected IBS that is able to withstand a horizontal impact load. Thus, this study aimed to investigate the performance of steel-bolt-connected IBS frames subjected to the sudden impact of hydrodynamic force. Autodesk computational fluid dynamic (CFD) simulation was used for optimizing the laboratory experiment. A 1:5-scale IBS frame was designed and tested for the dam-break test using 1 m, 2 m, and 3 m reservoir water levels. The results showed that the bolt connections were very effective and robust in the IBS frame. They also restricted damages from spreading to other structural components due to energy dissipation. The main findings of this study are crucial to improving the current IBS method of construction.

25 May 2024 in Acta Astronautica
Verified
Journal Article
Closed access
MZMuhammad Nazrif Zamani
Muhammad Nazrif Zamani
NNNorhazilan Md Noor
Norhazilan Md Noor
SUSarehati Umar
Sarehati Umar
MSMOHAMAD SHAZWAN SHAZWAN BIN AHMAD SHAH AHMAD SHAH
MOHAMAD SHAZWAN SHAZWAN BIN AHMAD SHAH AHMAD SHAH
NYNordin Yahaya
Nordin Yahaya
NTNg Chiew Teng
Ng Chiew Teng

26 November 2023 in Malaysian Journal of Civil Engineering
Verified
Journal Article
Open access
PDF file
AXAlan Wong Zong Xiang
Alan Wong Zong Xiang
SUSarehati Umar
Sarehati Umar
MSMohamad Shazwan Ahmad Shah
Mohamad Shazwan Ahmad Shah
SHSeyed Jamalaldin Seyed Hakim
Seyed Jamalaldin Seyed Hakim
Structural health monitoring techniques, particularly vibration-based damage detection, have gained significance in assessing civil structure condition. This paper focuses on utilising mode shape curvature for damage detection in a one-story steel frame structure. The study aims to overcome traditional inspection limitations by exploring vibration-based approaches. Experimental investigation is conducted to analyse intact and damaged structural modal behaviour. Modal analysis technique extracts modal frequencies and mode shapes, enabling analysis of mode shape curvature for damage detection and localisation. Preliminary findings show that damaged structures display deviations in mode shapes and reduced natural frequencies, providing evidence of structural damage. However, a significant issue arises near the support, where unexpected patterns emerge in the Total Damage Index (TDI) with increasing damage severity. This finding challenges the expected correlation between severity levels and TDI values, highlighting the need to consider factors like fixed supports. Misleading signs of damage in some segments underscore the importance of cautious result interpretation and accounting for noise. Future studies should focus on noise resistance, false indication mitigation, and understanding segments with fixed supports to enhance mode shape curvature analysis’s reliability for damage detection in civil structures.


20 October 2023
Verified
Preprint
Open access
PDF file
MSMOHAMAD SHAZWAN SHAZWAN BIN AHMAD SHAH AHMAD SHAH
MOHAMAD SHAZWAN SHAZWAN BIN AHMAD SHAH AHMAD SHAH
SUSarehati Umar
Sarehati Umar
SAShahrum Abdullah
Shahrum Abdullah
BABeng Hong Ahmad
Beng Hong Ahmad
MTMohd Nasir Tamin
Mohd Nasir Tamin
NNNoor Norhazilan
Noor Norhazilan
The research into fatigue fracture formulations for the Theory of Critical Distances (TCD) in concrete is advancing, with a focus on reducing the occurrence of fatigue failures in concrete structures. Despite design safety factors, concrete fatigue failures persist, and the associated fatigue tests are resource intensive. While TCD is known for its accuracy, it exhibits instability concerning variations in water-cement ratios in concrete mixes. The absence of standardized procedures further complicates fatigue testing, hindering research progress. This paper proposes a unified relationship between static and fatigue properties, streamlining fatigue characterizations through less laborious static tests. This research paves the way for Part B, which explores mathematical enhancements to this formulation. Together, Parts A and B aim to bridge knowledge gaps, offering a foundation for safer and more efficient concrete structures.