Vol.41/No.3(161)(2026)

Vol.41/No.3 (161) (2026)

Title

 

Investigation of
Failure Behavior of RC Beams Subjected to Repeated Loads With Acoustic
Emission Monitoring
Author

 

Yu-Cheng
Kan, Kuang-Chih Pei, Wun-Siang Lin
Keywords

 

 repeated load, RC beam, flexural, stiffness,
acoustic emission monitoring
Abstract 
This paper presents the static and dynamic flexural behavior of reinforced concrete beam based on a four-point bend test accompanying with the acoustic emission monitoring (AE) throughout the entire the load test. The dynamic load test starts with a load range from 10% to 80% of yielding load which is determined from the static load test, followed by increasing the upper load level to the post-yielding region with 1, 10, 100 and 1,000 of cycle numbers to examine the stiffness decay of the concrete beam until failure. Three loading rates of 0.5 Hz, 1.0 Hz and 2.0 Hz were adopted for dynamic load test. The test results showed that the concrete beams perform flexural behavior with a stable failure as being subjected to static load and with a sudden crushing manner as being subjected to dynamic load. Furthermore, the slower the loading rate, the more destructive it is to the concrete beam, the lower its bearing capacity, and the faster its stiffness decays. AE can reveal the disintegration processes inside reinforced concrete beams and provide early warning before failure occurs when the beam is subjected to static or dynamic loads.
Title

 

Implementing
High-Performance Computing for City-Scale Probabilistic Seismic Risk
Assessment: From Structural Modeling to Vulnerability Assessment in Hualien
Author

 

Peng-Yu Chen,
Ci-Xin Hsu, Sin-Ting Li, and Tsung-Lin Li
Keywords

 

high-performance
computing, city scale, probabilistic seismic risk assessment,reinforced
concrete frames, incremental dynamic analysis
Abstract 
Taiwan is located at an active plate boundary and is frequently affected by earthquakes. Many urban areas contain aging reinforced concrete (RC) buildings that may experience significant nonlinear response and damage during strong ground shaking. Therefore, assessing their seismic risk before future earthquakes is important for retrofit prioritization, disaster mitigation planning, and post-earthquake resource allocation. Conventional regional risk assessments often rely on empirical or simplified fragility curves, which may not fully capture the structural characteristics and nonlinear seismic behavior of individual buildings. Although probabilistic seismic risk assessment can provide more physics-based building-level risk estimates through nonlinear dynamic analyses and fragility functions, its application to city-scale building inventories requires a large number of repeated analyses and thus faces substantial computational challenges. To address this issue, this study develops a high-performance computing (HPC)-based framework for city-scale probabilistic seismic risk assessment. The framework integrates building inventory processing, automated structural model generation, incremental dynamic analysis, response post-processing, and fragility curve development. It is implemented on the National Center for High-performance Computing (NCHC) Forerunner 1 supercomputer, where dynamic task allocation is used to distribute building-level analyses across multiple central processing unit (CPU) cores. A case study is conducted for 62,454 RC buildings constructed before 1999 in Hualien County. Representative low-, mid-, and high-rise frame models are developed, and incremental dynamic analyses are performed using multiple ground-motion records and peak ground acceleration levels. The resulting fragility curves are further combined with ground-motion data from the 2024 Hualien 0403 earthquake to estimate building damage and compare the predictions with observed damage data. The results demonstrate the feasibility of using HPC for high-resolution city-scale seismic risk assessment.
Title

 

Optimization Design
of Inerter-Based Tuned Mass Dampers for a Jacket-Type Offshore Wind Turbine
Structure Under Seismic Excitation
Author

 

Qian-Rui Cai,
Yen-Chi Chen, Yu-Chieh Chen, Cheng-Hsien Shen, Peng-Tai Chan
Keywords

 

 jacket-type offshore wind turbine structure,
damper optimization, inverse element exchange method with multi-level
programming, inerter-based tuned mass damper 
Abstract 
Offshore wind turbines installed in seismic regions may be affected not only by wind and wave
loads but also by earthquake excitation, which can threaten structural safety. Therefore, effectively
reducing the structural dynamic response under seismic loading has become an important issue in
vibration control for offshore wind turbines. As turbine capacity and structural scale continue to
increase, conventional single tuned mass dampers (STMD) may show reduced control performance
because they are highly sensitive to tuning frequency. When structural frequency shifts and detuning
occurs, their vibration mitigation efficiency can decrease significantly. To improve the robustness and
efficiency of the control system, this study investigates a jacket-type offshore wind turbine structure
while considering the dynamic characteristics of the RNA. The control performance of single tuned
mass dampers (STMD), multiple tuned mass dampers (MTMD), single tuned mass damper inerters
(STMDI), and multi-tuned mass damper inerters (MTMDI) under seismic loading is evaluated.
In addition, the inverse element exchange method with multi-level programming (MulIEEM) and
the inverse element exchange method with greedy algorithm (GIEEM) are applied to optimize the
damper configuration. The differences between these optimization methods are compared in terms
of search efficiency, convergence behavior, and vibration reduction performance. The results show
that, under multiple earthquake time-history analyses, the MTMDI with inertance elements can
effectively reduce structural responses in most cases and demonstrates better control performance.
Both MulIEEM and GIEEM can improve damper configuration and enhance vibration mitigation
effectiveness. Overall, the proposed damper configuration and optimization methods can improve
the vibration control capability of offshore wind turbines under seismic loading and may serve as a
reference for future vibration control system design and engineering applications.
Title

 

Design and Performance Evaluation of BiocharReplaced Carbon-Negative 3D Printed Mortar
Author

 

Shou-Lun Chang,
Yen-Yu Yang, Hung-Wen Chen, Bing-Jean Lee
Keywords

 

 3D concrete printing, biochar, low-carbon
materials, sustainable construction
Abstract 
The construction industry is currently facing the dual challenges of net-zero carbon emissions
and intelligent construction. Three-dimensional concrete printing (3DCP) offers a promising
solution by combining material efficiency with automated construction. This study investigates
the incorporation of biochar, which has carbon sequestration potential, into 3D-printed
cementitious mortar as a partial mass replacement for the premixed non-shrink cementitious
product. The effects of biochar addition on rheological properties, mechanical performance, and
printability were systematically evaluated. A series of mortar mixtures with biochar replacement
ratios of 0.0%, 5.0%, 10.0%, 12.5%, and 15.0% was designed and tested. Various experiments
were conducted to examine the fresh and hardened properties of the mixtures. Manual printing
tests were further performed to simulate extrusion and layer-by-layer deposition, allowing the
buildability and practical feasibility of the mixtures to be assessed. The results are expected to
provide design guidelines for biochar-based 3DCP mortar and practical references for developing
sustainable buildings and low-carbon construction materials. This study supports the transition of
the construction industry toward intelligent and carbon-negative construction.
Title

 

Development and
Cyclic Testing of a New-Generation Knife-Plate-Connected Seismic Stud Column
Damper
Author

 

Po-Chien Hsiao,
Ting-Feng Chen
Keywords

 

seismic stud
columns, knife-plate connections, axial load effects, shear panel dampers
Abstract 
The knife-plate-connected seismic stud column (KSC) is a novel component applied in
special moment-resisting frames (SMF) to enhance energy dissipation efficiency. The KSC
consists of a steel shear panel damper (SPD) and boundary columns on both sides, which are
linked at both ends through knife-plate connections. This innovative design effectively adjusts
the deformation demands of the SPD, thereby improving its deformation capacity. This study
investigates the influence of axial loads on the seismic performance of KSCs through a two-stage
experimental program and verifies the effectiveness of an improved knife-plate connection design
(IKSC). A design methodology for boundary columns, including the transition zone (TZ) and
end connection (EC), is proposed. Experimental results indicate that applying axial loads has no
significant impact on the seismic performance of the KSC, though the cross-sectional dimensions
of the knife plate must be verified. Furthermore, by synthesizing historical research data, this
study establishes width-to-thickness ratio limits for KSC and IKSC sub-panels. The tests confirm
that the improved knife-plate connection of the IKSC effectively prevents fractures at the joints,
significantly enhancing the cumulative plastic deformation capacity of the component. Finally, a complete design procedure for KSC and IKSC systems is established and validated through experimental results.