Volume 2,2024 Issue 04

>Reviews

• Advancements in Sustainable Prestressed Concrete Bridge Technologies: A Comprehensive Review

  Seyedmilad Komarizadehasl, Al-Amin, Ye Xia, Jose Turmo

  2024,2(04):1-25, DOI: 10.59238/j.pt.2024.04.001

  Abstract(58) HTML(0) PDF(1.75 M)( 34)

  Abstract:Advancements in prestressed concrete bridge technology have increasingly focused on sustainability in response to growing environmental concerns. This review examines recent innovations in integrating recycled concrete aggregates (RCA) and supplementary cementitious materials (SCMs) within prestressed concrete to conserve resources, reduce waste, and lower carbon emissions. Sustainable prestressing techniques, including the use of fiber-reinforced polymer (FRP) tendons and shape memory alloys (SMAs), increase the durability of prestressed concrete bridges, extend service life, and minimize maintenance needs, thereby reducing environmental impact. Key methodologies, such as lifecycle assessment (LCA) and performance-based design, are highlighted for their roles in optimizing structural performance while reducing the ecological footprint. Despite the benefits, barriers to widespread adoption remain, including technical limitations, economic challenges, and regulatory constraints. To address these issues, this review proposes further research on material development, updated design guidelines, cost?benefit analyses, and supportive policy initiatives. The findings confirm that integrating sustainable materials and advanced technologies in prestressed concrete bridge construction offers environmental advantages without compromising structural integrity. Collaborative efforts among engineers, researchers, policy-makers, and educators are essential to overcoming these barriers and advancing sustainable, resilient infrastructure.

>Scientific Research

• Measurement of the Natural Frequency and Mode Shape of Prefabricated Concrete Wind Turbine Towers via the DIC Method

  Zhenwei Guo, Kangle Chen, Zhongze Sun, Lei Hong, Yan Xu, Sihang Wei

  2024,2(04):26-42, DOI: 10.59238/j.pt.2024.04.002

  Abstract(16) HTML(0) PDF(2.84 M)( 22)

  Abstract:Resonance between wind turbine towers and rotors can severely compromise the safety of wind turbines. This study proposes a measurement method based on the digital image correlation (DIC) technique for determining the natural frequencies of prestressed concrete towers. The approach employs high-pass filtering and wavelet transform to reconstruct vibration signals, followed by the use of Welch’s method to calculate the power spectrum of the reconstructed signals. The natural frequencies are identified from the spectral peaks, and the first- and second-order modes of the tower are determined through singular value decomposition (SVD). The measured first-order natural frequencies of the concrete tower under three operating conditions—turbine during stoppage, stable operation, and transition from stoppage to stable operation—are 0.2631 Hz, 0.2636 Hz, and 0.2782 Hz, respectively, whereas the second-order natural frequencies are 0.8624 Hz, 1.0397 Hz, and 0.8374 Hz, respectively. The first-order mode shapes correspond to unidirectional bending of the tower, and the second-order mode shapes correspond to reverse bending. The results demonstrate that the DIC method is an effective, convenient, and safe approach for measuring the natural frequencies of wind turbine towers, with significant practical value.

• Reasonable Completed State and Parameter Analysis of a Double-Deck Steel Truss Arch Bridge

  Zhengyang Zou, Jiahui Shan, Jishen Sun, Zuqian Jiang, Bin Sun, Rucheng Xiao

  2024,2(04):43-53, DOI: 10.59238/j.pt.2024.04.003

  Abstract(21) HTML(0) PDF(1.41 M)( 24)

  Abstract:Double-deck arch bridges are increasingly used to accommodate rising traffic volumes due to their excellent mechanical properties, ease of construction, and economic benefits. However, research on double-deck steel truss arch bridges is insufficient, particularly regarding the influence of various design parameters on structural performance. This study focuses on a large-span double-deck steel truss arch bridge as the research object. First, the cable force distributions and the effectiveness of the completed bridge state obtained from four different cable force optimization methods, analyzing the differences between these methods and identifying the most suitable approach for achieving an optimal bridge completed state. Next, it further studies the effects on the structure caused by changes in parameters such as the ratio of side span to mid-span, the height of the main beam truss, and the height of the main arch truss, and deeply discusses the mechanical mechanisms. Finally, it summarizes the patterns observed, providing a reference for the design of similar engineering projects.

>Design and Construction

• Research on Key Technologies for Anchor Methods in Pylon and π-Shaped Section Main Girder with Large Cantilevers of Huaizhou Tuojiang Bridge

  Qiang Wang, Yiyun Zhou, Kaisheng Feng, Shiwei Xiao, Zhiren Xiao

  2024,2(04):54-68, DOI: 10.59238/j.pt.2024.04.004

  Abstract(22) HTML(0) PDF(1.45 M)( 20)

  Abstract:Taking the prestressed concrete cable-stayed bridge of the Huaizhou Tuojiang Bridge as the background, the numerical calculation method was used to analyze the effects of circular prestressing and steel anchor boxes on the load bearing of the concrete pylon wall. The results show that, for medium- and small-span cable-stayed bridges, setting up either a circumferential prestress or a steel anchor box system alone cannot effectively solve the problem of tensile cracking in the concrete pylon wall. However, the combined effect of both systems is better. Additionally, a numerical analysis method is used to calculate the shear lag effect of the π-shaped cross-section main girder with a large cantilever under the completed bridge state, studying the distribution pattern of normal stress in this type of section and providing a reference for the design of similar structures.

>Product Research and Development

• Exploration for New Technology of Assembled Corrugated Steel Web Composited Beam

  Xiaoquan Guo, Shihong Zhang, Changjian Zhao

  2024,2(04):69-82, DOI: 10.59238/j.pt.2024.04.005

  Abstract(30) HTML(0) PDF(1.53 M)( 14)

  Abstract:Improving the prefabrication and assembly level of composited beams with corrugated steel web is key to promoting their application in bridge engineering for medium-span bridges. This paper first derives the principle of 'vertical composite force invariance' unique to composite beams with corrugated steel webs, and validates this principle using finite element structural models. Based on this, four new types of prefabricated and assembled continuous composite beams with corrugated steel webs are developed, and their respective characteristics are analyzed to provide references for other engineering practices.

>Project Report

• Design and Analysis of a Large-Span Spiral Spatial Antisymmetric Ribbon Landscape Arch Bridge

  滕小竹

  2024,2(04):83-95, DOI: 10.59238/j.pt.2024.04.006

  Abstract(11) HTML(0) PDF(2.01 M)( 15)

  Abstract:The Xiaohe River Bridge on Dayun Road is the world's first large-span spiral-shaped spatially asymmetric landscape arch bridge. This bridge breaks through the traditional arch bridge design, refining the curve elements and transforming them into a closed spiral-shaped spatial ribbon arch bridge comprising two spans of asymmetric ribbon inclined secondary arches and a single span of a diagonal main arch. This design creates a sense of passage and dynamic movement, with nested arches and landscapes. The bridge has a total span arrangement of 65+110+110+65 = 350 m. The main beam and transverse beams are connected with the main and secondary arches, forming an arch?beam joint system. This structure transforms the mechanical properties of the irregular spiral-shaped spatially asymmetric ribbon landscape arch bridge into an arch–beam composite system. This system is characterized by structural self-balancing and no horizontal thrusts. The main and secondary arch ribs are designed with parabolic arch axes and box-type cross sections. The main arch span is 229 m, which is the largest diagonal spanning arch bridge in China. The transition segments (the arch feet) connecting the main and secondary arches with the transverse beams are twisted surface components made from Q370qD steel with a plate thickness of 40 mm. The main beam adopts a semi-closed double-sided steel box section. The bridge has undergone comprehensive analyses, including spatial static, fatigue, stability, and seismic performance evaluations, as well as refined analysis of the arch feet. The results indicate that the structure is safe, reliable, and meets the relevant design code requirements.

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