Tran-Van Han

Steel modular construction offers advantages in speed, cost, and sustainability, but its adoption is constrained by connection efficiency. This study introduces the Samsung Connection Node (S-CN), a novel cast-steel connector fabricated using 3D-printed sand molds. Full-scale tests on roof nodes, floor nodes, the connector, and a beam–column assembly under axial compression were conducted, supported by finite element (FE) and analytical studies. Roof nodes carried 10% higher loads than floor nodes, while connector strength was governed by tie plate deformation and local buckling. Beam restraint improved load utilization, producing higher uniformity of strain. Code-based predictions (AISC 360-16 EN 1993-1-1) provided conservative agreement with experiments and FE. A mechanics-based model clarified that rim bearing controls global capacity, while yield-line mechanisms explain local deformation. Parametric studies highlighted the strong influence of node thickness and adverse effects of large openings or excessive column height. Supplementary FE analyses under combined axial–moment loading indicated a stable numerical response of the connector and suggested robustness under service-level eccentricities. A nonlinear pushover analysis of a corner subassembly suggested a ductility ratio of 7.5 with drift ratios below the ASCE 7 and Eurocode 8 near-collapse limits in the numerical model; these seismic-related findings are preliminary and require future experimental validation.

This study examines the structural performance of a U-profile fastening system designed to connect timber frame façades (TFFs) to concrete slabs in hybrid timber–concrete construction. The system consists of U-shaped steel profiles with flange cutouts, partially embedded in concrete to facilitate early-stage façade installation. Fifteen full-scale specimens, varying in embedment depth, cutout geometry, and concrete compressive strength, were tested under simulated wind loads representing suction conditions. Concrete cone breakout was identified as the predominant failure mode. Experimental results indicated that embedment depth and concrete strength were the main factors governing anchorage resistance. In contrast, variations in cutout geometry and localized reinforcement had minimal influence. Finite element simulations captured the overall structural behavior and failure mechanisms with acceptable accuracy, showing a maximum deviation of 7% in peak load relative to experimental results. An analytical model, based on the Concrete Capacity method and existing design standards, was developed to estimate anchorage capacity and showed consistent agreement across the tested configurations. The findings contribute to the structural design of timber–concrete façade connections incorporating embedded U-profile connectors.

This study assesses the acoustic performance of a novel thermal break system with composite cores through both experimental testing and Finite element (FE) analysis. The research explores the effects of varying the thicknesses of key materials, including Expanded Polystyrene (EPS), Cellulose Fiber Reinforced Cement (CRC) boards, and Melamine foam, on sound insulation while maintaining a constant overall thickness of the thermal break. Results show that reducing EPS thickness and increasing CRC or Melamine foam thickness by 12 mm, along with strategic layering of Melamine with CRC boards, enhances sound insulation by 2–5 decibels (dB). The configuration with the thickest Melamine foam layer achieved the highest sound insulation improvement, ranging from 2 to 6 dB over other configurations. Additionally, FE vibro-acoustic analysis proved to be a reliable predictor of acoustic performance, closely aligning with experimental data. A parametric study further revealed a nearly linear correlation between EPS layer thickness and sound insulation efficacy. These findings underscore the crucial role of material selection and strategic layering in designing thermal breaks that effectively balance sound and thermal insulation, contributing to improved environmental quality and occupant comfort in buildings

Impact sound transmission in concrete slabs is a persistent challenge in building acoustics, particularly in residential and commercial environments. This study introduces a novel floating floor design utilizing polyurethane cushions of various 3D shapes and sizes to mitigate impact noise. The aim is to improve acoustic performance across a wide frequency spectrum while maintaining flexibility and practicality in installation. Two floating floor configurations — fully-filled and half-filled systems — were experimentally tested on twenty-two specimens under controlled laboratory conditions. Fully-filled systems achieved significant impact sound reductions of up to 6.8 dB, delivering consistent performance in mid to high frequencies and low frequencies when appropriately configured. In contrast, half-filled systems were effective at controlling low-frequency noise but demonstrated limitations at higher frequencies due to resonance sensitivity and variability in configurations. Parametric studies revealed that optimizing polyurethane cushion properties, such as elastic modulus and height, enhanced overall impact sound performance. Additionally, incorporating lightweight concrete layers significantly improved low-frequency insulation. Fully-filled systems consistently outperformed conventional methods, delivering comprehensive and reliable sound insulation. However, half-filled systems require further refinement for broader acoustic applications. This research highlights the critical role of cushion material properties, structural configurations, and multi-layer designs in effective impact sound control, providing a solid foundation for next-generation floating floor systems tailored to advanced acoustic insulation needs.

The novel S-CN (Samsung Connection Nodes) connection system, featuring nodes crafted from 3D-printed sand molds and integrated with vertical and horizontal components paired with rectangular hollow section (RHS) members, provides an effective method for connecting modules in steel modular buildings. This study employs experimental and numerical methods to assess the axial compression and tensile capacities of vertical connections, as well as the shear capacities of horizontal connections. Results show that the vertical connection’s axial capacity is significantly influenced by the thickness of the roof node’s top plate. While the reduction in area due to the roof node’s openings affects compression performance, it has minimal impact on tensile performance. Similarly, the shear capacities of horizontal connections depend on the capacities of their shear pins. The parametric study reveals that increasing the thickness of the roof node’s top plate leads to a linear increase in both the ultimate tensile and compression loads of the vertical connections. Additionally, increasing the diameter of the shear pins results in a modest increase in the ultimate shear load of the horizontal connections. **BibTeX**:

 @articlehan2025experimental, title=Experimental and numerical evaluation of the structural performance of novel S-CN connections in modular construction, author=Han, Tran-Van and Jeong, MoonSook and Kim, YongNam and Lee, Dongkyu and Cuong, Nguyen Huu and Lee, Kihak, journal=Structures, volume=71, pages=107930, year=2025, publisher=Elsevier  

The pulley wireway system, a novel lighting support system reinforced with a pulley friction damper, can become an attractive earthquake-resistant alternative to conventional lighting systems in buildings. The goal of this research was to conduct a thorough evaluation of the seismic energy dissipation capacities of both a novel and an existing lighting support system under artificial earthquakes of varying magnitudes, generated using the ICC-ES AC156 standard. This was achieved by conducting tri-axial shaking table tests on two specimens suspended from the same height and using the same connector type. The experimental results demonstrated that the newly developed lighting support system with the damper was effective in reducing seismic energy and peak oscillation. The effectiveness of the damper was directly proportional to the magnitude of the earthquake, resulting in excellent adaptability of this innovative system to a wide range of earthquake events.