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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Thermoplastic Composites by 3D Printing and Automated Manufacturing to Extend the Life of Transportation Facilities</title>
      <link>https://trid.trb.org/View/2672993</link>
      <description><![CDATA[Large-scale thermoplastic polymer extrusion-based additive manufacturing (AM) has been used to fabricate precast concrete formworks. There are some limitations inherent to the large-scale AM process that need to be overcome to design complex, multipart additively manufactured formworks to be used for precast concrete. This research work uses a large-scale polymer composite AM process to manufacture two-part formworks. Postprocessing was used to repair imperfections, create smooth casting surfaces, achieve precise dimensional tolerance, and incorporate assembly mechanisms for multipart formwork. Two biodegradable polymer composites (wood-fiber polylactic acid and wood-fiber amorphous polylactic acid) and a conventional polymer composite (carbon fiber acrylonitrile butadiene styrene) were selected to manufacture four sets of two-part formwork. Design details, including the cellular infill pattern, continuous toolpath, and layer time selection, are presented. Postprocessing and repairs performed on the manufactured formworks to get the required dimensional tolerance and surface smoothness are discussed.]]></description>
      <pubDate>Tue, 10 Mar 2026 09:54:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/2672993</guid>
    </item>
    <item>
      <title>Tire powder-enhanced jute/epoxy composites: Performance improvement and design optimization for formwork sheathing panel</title>
      <link>https://trid.trb.org/View/2625174</link>
      <description><![CDATA[This study explores the development and optimization of a tire powder-enhanced jute/epoxy composite for formwork sheathing applications, addressing the limitations of conventional materials such as plywood, steel, timber, and plastic. The proposed hybrid composite aims to provide an economical, lightweight, and durable alternative while promoting sustainability through waste tire recycling. Experimental investigations assessed the mechanical and physical properties of eight composite laminates by modifying the epoxy matrix with varying tire powder content and incorporating recycled tire powder as a core sandwich in a jute/epoxy composite. The Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method identified L2 (20 % jute, 80 % epoxy, 4 % tire powder) as the optimal configuration, offering a superior balance of tensile, compressive, flexural, and impact strengths, along with reduced water absorption, improved density and cost efficiency. To further refine the sheathing panel, Genetic Algorithm (GA) optimization was applied, minimizing weight while ensuring structural integrity. The optimized panel features layer thicknesses of t1 = t2 = t3 = 2.5 mm and fiber orientations of 90°, 0°, and 90°, resulting in a minimal weight of 24.41 kg. Compared to conventional sheathing materials, the composite demonstrates significant weight reductions, including 37.73 % less than plastic (39.2 kg), 82.31 % less than steel (138 kg), 49.15 % less than plywood (48 kg), and 53.06 % less than timber (52 kg). Finite Element Analysis (FEA) validated the optimized design, confirming a high stiffness-to-weight ratio and a safety factor exceeding 2, ensuring reliability under applied loads. These results demonstrate that tire powder-enhanced jute/epoxy composites offer a sustainable, cost-effective, and high-performance alternative for formwork sheathing in construction.]]></description>
      <pubDate>Thu, 22 Jan 2026 09:24:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2625174</guid>
    </item>
    <item>
      <title>Evaluation of permanent 3D printed formwork of a bridge pier using non-destructive testing methods</title>
      <link>https://trid.trb.org/View/2578653</link>
      <description><![CDATA[In recent years, 3D concrete printing (3DCP) has emerged as a promising method for automated construction. One of the main challenges of 3DCP today is the problematic placement of rebars, which complicates the creation of load-bearing structural elements. One way to address this problem is to use 3DCP elements as permanent concrete formwork. Although this method has been utilized in several engineering projects, there remains a very limited number of studies on the quality control and evaluation of structures with 3DCP permanent formwork. In the study presented, the authors applied several elastic-wave-based methods of Non-Destructive Testing (NDT) for the evaluation of 3DCP permanent formwork of a bridge pier, whose footing was constructed using such formwork. The results showed that, using methods of NDT, it is possible to detect and evaluate defects in the 3DCP formwork and the quality of bonding between the 3DCP permanent formwork and the post-cast concrete.]]></description>
      <pubDate>Mon, 08 Sep 2025 14:54:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/2578653</guid>
    </item>
    <item>
      <title>Research on the Template Load Values and Structural Stress Variation Laws of Secondary Lining Trolley Under Tunnel Pouring Conditions</title>
      <link>https://trid.trb.org/View/2577170</link>
      <description><![CDATA[Existing methods for calculating tunnel formwork loads often reference those used in building construction, despite significant differences in pouring processes. To address the errors in current load values that affect tunnel lining quality, this study proposes calculation methods for lateral and top formwork loads specific to tunnel trolleys. A combination of numerical simulations and field measurements was used to validate the proposed methods and summarize the structural stress and deformation patterns of the trolley during pouring. Results indicate that during wall pouring, the hardening of concrete significantly affects lateral loads, with the proposed lateral pressure attenuation coefficient a bringing the simulation results closer to measured values. During arch pouring, the distribution range of localized grouting pressure greatly affects the stress on the top formwork. The stress variation in the pillars shows significant differences under asymmetric conditions, while stresses tend to equalize under symmetric pouring. For the beams, stress variation indicates that under asymmetric conditions, the left beam experiences compression while the right beam experiences tension, whereas stresses equalize under symmetric conditions. The proposed load calculation methods align more closely with actual tunnel conditions and offer valuable insights for engineering applications.]]></description>
      <pubDate>Tue, 22 Jul 2025 08:56:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/2577170</guid>
    </item>
    <item>
      <title>Ultra-high performance rubberised concrete slabs cast in stay-in-place formworks: Enhancing shear strength and vibration characteristics</title>
      <link>https://trid.trb.org/View/2555958</link>
      <description><![CDATA[This study investigated innovative bridge slabs using ultra-high-performance rubberized concrete (UHPRuC) combined with special square hollow stiffeners (SHS) or Y-shaped stiffeners. The newly developed UHPRuC was prepared using crumb rubber, silica sand, hooked-end steel fibers, cement, silica fume, and superplasticizer. Four slabs were prepared: two measuring 1400 mm× 600 mm x 75 mm without glass fiber-reinforced polymer (GFRP) SIP formwork, and another two measuring 1400 mm× 600 mm x 65 mm with GFRP SIP formwork. The results showed that incorporating 20 % crumb rubber into UHPRuC increased the damping ratio by 1.5 times and the maximum strain by 3.5 times compared to reference slab. Furthermore, the Y-shaped stiffener significantly enhanced the ultimate loading capacity and resistance to shear stress, and the UHPRuC slabs cast on GFRP SIP formwork demonstrated a 60–91 % improvement over normal-strength concrete slabs. Slabs without GFRP SIP formwork experienced a flexural-shear failure, while slabs with GFRP SIP formwork exhibited predominantly shear failure. Finally, a comparison between experimental data and theoretical predictions revealed that the punching shear strength of the SHS slab closely matched the experimental results, with a 4 % difference. However, the Y-stiffened slab exhibited an experimental value that was 44 % higher than predicted.]]></description>
      <pubDate>Tue, 08 Jul 2025 09:56:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/2555958</guid>
    </item>
    <item>
      <title>Material and structural fatigue performance of 18 m-span reinforced arch structure manufactured by 3D printing concrete as permanent formwork</title>
      <link>https://trid.trb.org/View/2510953</link>
      <description><![CDATA[This paper proposes a rapid construction method using 3D printed concrete as permanent formwork followed by conventional reinforcement installation and cast-in-place concrete, which has been successfully applied to the real practice of 3D printing bridge in China. In this paper, a basalt fiber reinforced cementitious composite was prepared for 3D printing large-scale formwork. The printable and mechanical properties of the basalt fiber reinforced 3D printing materials were systematically investigated and the requirement for formwork application had been met. Meanwhile, the effect of interlayer on long-term durability, e.g, the carbonation and frost resistances of the 3D printed concrete formwork were investigated through accelerated carbonation and freeze-thaw cycles tests. The interlayer regions perform 326 % larger carbonation depth than filaments matrix. The 3D printed specimens show 147 % higher weight loss ratio at 200 freeze-thaw cycles compared to cast ones. Additionally, the optimized 3D printed concrete was adopted for the manufacturing of largescale reinforced arch structures with a net span of 18 m. To evaluate the structural integrity of reinforced arch structure with 3D printed concrete formwork, fatigue testing with 2 million cycles at 40 %–60 % of the design load capacity was performed. Experimental investigations validated the favorable bonding of the 3D printed formwork. The construction practice of 3D printed arch structure for bridge project was illustrated.]]></description>
      <pubDate>Fri, 28 Mar 2025 09:10:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2510953</guid>
    </item>
    <item>
      <title>A case study on the impact of fiber distribution on X-connections of complex-shaped UHPFRC footbridges cast with recyclable formwork</title>
      <link>https://trid.trb.org/View/2486128</link>
      <description><![CDATA[Ultra-High Performance Fiber Reinforced Concrete (UHPFRC) is emerging as a transformative construction material, enabling the creation of slender, thin architectural structures with outstanding surface textures. This study examines the influence of fiber distribution on the mechanical behavior of the X-connection, a critical structural detail in a novel latticework concept for UHPFRC footbridges, while also introducing an innovative approach using recycled wax formwork for shaping complex geometries.Following the architectural design process for the latticework UHPFRC footbridge, the methodology involves: (i) fabrication of fully recyclable wax formwork using CNC milling for two X-connection configurations with distinct crossing angles (i.e., the angle formed at the intersection of the X shape); (ii) gravity casting of UHPFRC, incorporating 1 % steel microfibers; (iii) application of the magnetic inductance method (MIM) for non-destructive testing to evaluate fiber distribution, supplemented by fiber counting and image analysis of cracked sections post-testing; (iv) mechanical testing of the X-connection under bending to assess structural performance; and (v) a nonlinear Finite Element Analysis (NLFEA) to comprehensively examine the impact of fiber distribution. The findings underscore the pivotal role of fiber distribution in determining the ductility and strength of X-connections within the latticework UHPFRC footbridge, elucidating both the strengths and constraints of contemporary magnetic methods integrated with the Finite Element Method for accurately predicting the effects of fiber distribution.]]></description>
      <pubDate>Wed, 22 Jan 2025 16:58:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2486128</guid>
    </item>
    <item>
      <title>Seismic performance of Fe-SMA prestressed segmental bridge columns with 3D printed permanent concrete formwork</title>
      <link>https://trid.trb.org/View/2415424</link>
      <description><![CDATA[The integration of digital fabrication technology with prestressed segmental column construction offers significant potential for accelerated bridge construction with material-efficient design. This study aims to explore this potential by developing a novel prestressed segmental column system that utilizes permanent 3D printed concrete (3DPC) formwork for column segment fabrication. Prestressing is achieved in the proposed system by using partially bonded iron-based shape memory alloy (Fe-SMA) reinforcement. Large-scale experiments were conducted on two columns under combined gravity and lateral loading to evaluate the seismic performance and feasibility of the proposed system. The ratio of steel to Fe-SMA reinforcement in the column design was the variable considered in this study. The experimental results showed that the columns could withstand lateral drifts of up to 5% without collapse and the permanent 3DPC formwork showed no premature failure or delamination. Furthermore, the columns exhibited self-centering characteristics, maintaining a residual drift of 1% up to a target drift of 4% when the reinforcement ratio of steel to Fe-SMA rebars was 0.3. The results highlight the potential of the proposed prefabrication concept in designing material-efficient and seismically resilient bridge columns with low damage characteristics.]]></description>
      <pubDate>Mon, 09 Sep 2024 09:56:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/2415424</guid>
    </item>
    <item>
      <title>Innovative bridge deck solutions: Examining the impact response and capacity of UHPC with FRP stay-in-place formworks</title>
      <link>https://trid.trb.org/View/2399426</link>
      <description><![CDATA[This study investigates the impact behaviour of bridge decks constructed with ultra-high-performance concrete (UHPC) and fibre-reinforced polymer (FRP) stay-in-place (SIP) formwork. Eight scaled bridge decks were fabricated and tested under pendulum impacts. Two different FRP SIP formwork configurations, i.e., square hollow section (SHS) and Y-shaped stiffened, were considered. Two types of reinforcing bars, i.e., steel and glass FRP (GFRP), were adopted for these samples. The influence of impact velocity on the transient response and progressive damage of the concrete decks under impact loading was investigated. The test results showed that UHPC and Y-shaped stiffeners were effective in decreasing the peak and residual displacements of decks by up to 70 % when compared to decks made with normal strength concrete. UHPC and Y-shaped stiffeners greatly improved the impact and residual impact capacities. The use of GFRP rebars instead of steel reinforcement changed the failure mode and FRP SIP formwork reduced deck damage and mitigated scabbing failure under impact loads. The configuration of FRP SIP formwork had a substantial influence on the impact force and thus the deck’s performance. Especially, this study has observed an interesting phenomenon under impact, i.e., reaction force could be greater than impact force, which has not been reported in the literature yet.]]></description>
      <pubDate>Fri, 23 Aug 2024 15:27:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/2399426</guid>
    </item>
    <item>
      <title>A simplified approach to assess dynamic amplification due to accidental release of formwork traveller during the construction stages of bridges</title>
      <link>https://trid.trb.org/View/2345934</link>
      <description><![CDATA[Construction of bridges by the cantilever method needs to consider the accidental release of the formwork traveller (ARFT) in the design phase. Often this phase is a critical situation that current regulations treat as a static analysis amplified by a dynamic factor due to the difficulty in setting up a model able to simulate the complex interaction between the formwork and the structure in the time domain during the accidental release. To overcome the simplistic approach of the regulations and to avoid the complexity of detailed ARFT modelling, in this research the release of the formwork is modelled as a simple force-time function applied to the bridge. This function has an equivalent effect on the structure as the accidental release, and it has been tuned using experimental tests on a 1:100 scale aeroelastic model of the cable-stayed Bioceanic Bridge. To test the applicability of the proposed time-function the Chilina continuous beam Bridge was also analysed. The article shows that the simplified procedure in the regulations can sometimes underestimate and overestimate dynamic amplification and, thus, a methodology is proposed to carry out the specific dynamic calculation that the regulations suggest for those cases where it is necessary.]]></description>
      <pubDate>Fri, 29 Mar 2024 10:01:12 GMT</pubDate>
      <guid>https://trid.trb.org/View/2345934</guid>
    </item>
    <item>
      <title>The benefits of using InQuik Accelerated Bridge Construction Systems</title>
      <link>https://trid.trb.org/View/2306865</link>
      <description><![CDATA[The InQuik Bridge System is an Australian innovation that was first conceptualized in 2015. Since its introduction into the market in 2017, it has been rapidly adopted in the Australian bridge market, with more than 160+ bridges in service or under construction, from 6 to 70 m in length. Along with being utilized to replace destroyed bridges after natural disasters, the system has rapidly become the industry leader in the Accelerated Bridge Construction (ABC) sector across Eastern Australia, which is a testament to the revolutionary nature of the technology. Substantial research has been conducted on the engineering methodology, which has highlighted many benefits over conventional bridge construction methods. This document explores these benefits.]]></description>
      <pubDate>Thu, 07 Dec 2023 14:55:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2306865</guid>
    </item>
    <item>
      <title>Samverkande bropelare med kvarsittande 3D-utskriven betong och igjuten SKB</title>
      <link>https://trid.trb.org/View/2269733</link>
      <description><![CDATA[The most common way to produce bridge piers is to build a mold and fill it with concrete. Form building takes time and even if the form wood or steel form can be reused sometimes it is still about increased material costs. In a preliminary study, we investigated if the shape instead can be created with a 3D printer and concrete. The form then becomes part of the pillar and can contribute to both load-bearing capacity and durability. If self-compacting concrete is used for the cast-in-place concrete, two effective techniques are combined, 3-D printed concrete (3DP) and self-compacting concrete (SKB). Two promising graduate work has been carried out at KTH in collaboration with LTU and the companies ConcretePrint and Betong Indust. This project picks up where the pre study ended. The project is mainly experimental and in that includes four reinforced interaction columns with permanent 3D printed concrete form and cast SKB. The columns will be compared against two homogeneous SKB columns cast conventionally. The aim of the project is to further develop the technology with cooperating bridge piers permanent 3D-printed concrete form and cast self-compacting concrete based on a promising preliminary study. Concrete goals are to quantify the collaboration pillars carrying capacity and performance.]]></description>
      <pubDate>Mon, 16 Oct 2023 09:26:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2269733</guid>
    </item>
    <item>
      <title>A Comprehensive Literature Review of Stay-In-Place Form for All Types of Bridge Elements as a Means to Reduce the Demand on Skilled Workers</title>
      <link>https://trid.trb.org/View/2255707</link>
      <description><![CDATA[It is widely known and accepted that the demand on skilled construction work force is higher than ever as the older generation of construction personnel is not getting replaced by a younger generation. This clearly initiates the thought process for exploring creative ways to reduce the demand on skilled workers by introducing construction approaches and practices that minimize the need to employ skilled workmanship. One of such innovative techniques serving the bridge construction industry is the implementation of stay-in-place structural forms that are readily available formwork and external reinforcement that eliminates the need to build and remove falsework being in the bridge decks, bridge girders and bridge piers. Because fire is a recognized hazard in these situations, the targeted elements will be conventionally reinforced for redundancy while the Stay-in-Place (SIP) system will be available as the main reinforcement system. In this project, a comprehensive literature review will be performed of all research and existing projects using SIP form technology. Furthermore, the project will identify specific negative issues with SIP forms, such as problems with inspection or with corrosion, and the corresponding mitigations that might be available. These issues will be addressed individually and the known or proposed solution will all be documented. The proposed research will target a comprehensive state-of-the-art literature review of all the bridge elements utilizing the SIP technology. This includes but is not limited to bridge deck, bridge girder and bridge pier construction in addition to all the other complementary elements like cross girders. The literature review will include the experimental prototypes as well as the actual project implementations in bridges performed by the United States DOT’s, Canada and the rest of the world. The specific literature review research tasks include: 
(1) Identifying a historical perspective for this technology in each bridge element application to link it to the current state-of-the-art construction techniques. 
(2) Surveying all the full-scale experimental investigations performed highlighting the main take away conclusions. 
(3) Establishing a database of all implementation projects that have utilized this technology in the US, Canada and the rest of the world. 
(4) Performing a comprehensive review of the design documents and construction specifications available to the engineering community 
(5) Building flow charts that facilitates the effective implementation strategies of this technology. 
(6) Writing and submitting the final project report. ]]></description>
      <pubDate>Tue, 26 Sep 2023 14:27:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2255707</guid>
    </item>
    <item>
      <title>Development of GDOT Ultra-High Performance Concrete for Bridge Deck Closure Pours</title>
      <link>https://trid.trb.org/View/2221870</link>
      <description><![CDATA[The use of precast prestressed girders with composite precast deck panels along with the use of precast prestressed  deck bulb-T girders provide for more economical bridges because of their ability to utilize accelerated bridge  construction techniques. The use of concrete deck panels and deck bulb-T systems require the use of closure pours  between the units. Ductal™, a proprietary ultra-high performance concrete (UHPC), has been shown to provide an  outstanding link between deck segments for closure pours as narrow as 6-in, but Ductal is expensive. This research  develops a concrete based on locally available materials (GDOT-UHPC), which has a direct tensile strength greater  than 750 psi and ductility and toughness under tensile loads such that the concrete can develop the tensile yield  stress of #5 (⅝-in. diameter) reinforcing bars within a 5-in. embedment length. Minimizing the width of the closure  between deck and bulb-T units provides further economies by greatly simplifying formwork and eliminating  shoring. Testing assured not only the short development length of reinforcement but also ultimate strength capacity  of transverse and longitudinal closure pours. Further, best practices for formwork, closure design, UHPC mixing  and placement, and quality assessment are considered.]]></description>
      <pubDate>Wed, 09 Aug 2023 13:23:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2221870</guid>
    </item>
    <item>
      <title>Behavior of Ultrahigh-Performance Concrete Bridge Decks with New Y-Shape FRP Stay-in-Place Formworks</title>
      <link>https://trid.trb.org/View/1941921</link>
      <description><![CDATA[This study proposes using glass fiber–reinforced polymer (GFRP) as a stay-in-place structural formwork for casting bridge decks with ultrahigh-performance concrete (UHPC). The GFRP stay-in-place formworks completely replace the bottom layer of rebars, and the top steel reinforcement is also replaced by a GFRP mesh to mitigate the corrosion damage. The formworks were either a flat GFRP plate with square hollow section (SHS) stiffeners or a flat GFRP plate with new Y-shape stiffeners. Concentric static tests on five 1:2.75 scale decks were performed to investigate the effect of stiffener's configuration and the influence of the concrete strength on the performance of bridge decks. Rotational fixity support was used to simulate a real bridge deck connection of supporting girders. All specimens with the stay-in-place formwork exhibited punching shear failure. It was found that the use of Y-shape stiffeners significantly improved the load-carrying capacity of the proposed deck. Replacing normal concrete with UHPC further improved the loading capacity of the deck. The decks demonstrated excellent performance, with the load-carrying capacity 3.8–9.5 times higher than the established equivalent service load depending on the concrete strength and configuration of the GFRP stay-in-place formwork. Deflection at service load was less than span/1,600 for all the decks. Compared with normal-strength concrete (34 MPa), UHPC improved the maximum load-carrying capacity of the deck from 91.4 to 149 kN.]]></description>
      <pubDate>Mon, 27 Jun 2022 17:16:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/1941921</guid>
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