<rss version="2.0" xmlns:atom="https://www.w3.org/2005/Atom">
  <channel>
    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
    <description></description>
    <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>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
    </image>
    <item>
      <title>Comparison of Formability Performance Between CR550LA and CR590DP</title>
      <link>https://trid.trb.org/View/2691960</link>
      <description><![CDATA[While rapid development of advanced high strength steels (AHSS) for a safer and lighter vehicle has been a primary focus in the automotive industry, the application of traditional high strength low alloy (HSLA) steel continues to be actively supported and developed. AHSS are often used to replace HSLA steels for downgauging while maintaining similar or better performance in crashworthiness and durability. However, recent developments have enabled the availability of higher strength, cold-rolled HSLA steels that could offer opportunities for a more balanced solution between material cost and material performance. Certain higher strength HSLA steels not only offer a cost-effective way to increase the strength-to-weight ratio but also provide comparable formability and better weldability to AHSS.In this study, cold rolled HSLA grades of CR420LA and CR550LA are evaluated in overall formability and in-use performance when compared to CR590 dual phase (DP) grade. The evaluations performed include both global and local formability tests such as forming limit curve (FLC) testing, true fracture strain, half specimen dome and hole expansion tests. Experimental results indicate that CR550LA tends to have a slightly better local formability but slightly lower global formability than CR590DP. The results demonstrate these higher strength, cold-rolled HSLA steels can potentially be used to replace CR590DP for certain components.]]></description>
      <pubDate>Thu, 30 Apr 2026 16:39:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/2691960</guid>
    </item>
    <item>
      <title>Comparative Study of Crash Performance and Lightweight Effect between Steel Roll-formed and Aluminum Extruded Bumper Beams</title>
      <link>https://trid.trb.org/View/1998827</link>
      <description><![CDATA[Automobile bumper beam which is one of the most important safety parts during front crash accident, is mainly subjected to a bending load and plays a key role in absorbing energy in collisions and protecting occupants. In this study, firstly a benchmark study about the material, manufacturing method and key external dimensions of bumper beam was performed. It is found that it has mainly the following kinds of structures: steel or aluminum press forming, steel roll forming and aluminum extrusion. And then steel roll-formed and aluminum extruded bumper beams which have a characteristic of constant cross section along the longitudinal direction were chosen, and a comparative study of crash performance and lightweight effect was conducted via numerical simulation. In which, the lightest aluminum extruded bumper beams according to required performance were obtained by using optimization design technology and the design guidance for thickness values of bumper beam walls became clear. The applicable areas of steel roll-formed part and aluminum extrusion were clarified by comparing the structural results of five types of external dimensions.]]></description>
      <pubDate>Wed, 24 Aug 2022 15:05:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/1998827</guid>
    </item>
    <item>
      <title>Development of New Vehicle Safety Structures by Using
                    Third-Generation Steels</title>
      <link>https://trid.trb.org/View/1905502</link>
      <description><![CDATA[
                
                Research and development efforts in the automotive industry have been long
                    focused on crashworthy, durable vehicles with the lowest mass possible as higher
                    mass requires more energy and, thus, causes more CO2 emissions. One
                    way of approaching these objectives is to reduce the total vehicle weight by
                    using higher strength-to-weight ratio materials, such as Advanced High-Strength
                    Steels (AHSS). Typically, as the steel gets stronger, its formability is
                    reduced. The steel industry has been long developing (so-called)
                    third-generation (Gen3) AHSS for the automotive industry. These grades offer
                    higher formability compared to first-generation (Gen1) and cost less compared to
                    the second-generation (Gen2) AHSS. Transformation Induced Plasticity
                    (TRIP)-aided Bainitic Ferrite (TBF) and Quenching and Partitioning (Q&P)
                    steel families are considered to be the Gen3 AHSS. These grades can be
                    cold-formed to more complex shapes, compared with the Gen1 Dual Phase (DP) and
                    TRIP steels at equivalent strength levels. In this article, new single-piece A-
                    and B-pillar reinforcements were designed using a Gen3 AHSS, TBF980.
                    Spot-welding operations were eliminated due to part consolidation with the more
                    formable steel. These parts will be the first structural automotive parts which
                    were manufactured with cold-forming technology using TBF steels with a sstrength
                    level close to 1 GPa or even more. Weight and cost reductions were realized by
                    the new design while improving the crash performance.
            ]]></description>
      <pubDate>Mon, 28 Feb 2022 09:42:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/1905502</guid>
    </item>
    <item>
      <title>An Analytical Model for Spring-Back Prediction in U-Channel Forming with Advanced High Strength Steel</title>
      <link>https://trid.trb.org/View/1561164</link>
      <description><![CDATA[Spring-back phenomena are critical in stamping procedures for advanced high strength steel. An analytical model is developed to predict the spring-back effect for a U-channel part with post-stretching process. The stress distribution is obtained by direct application of material constitutive relationship. The subjected loading conditions are sequentially bending, (un-bending), and uniform stretching, based on different zones in the part. Both the loading history and the friction effects are considered in the model. The bending moments are obtained to generate a theoretical spring-back shape. Great performance in spring-back control is achieved by applying certain high level of external forces. FE simulation is conducted for the identical stamping process with post-stretching. Good correlation is observed between the analytical and numerical solutions/experimental results under various scenarios.       ]]></description>
      <pubDate>Fri, 20 Dec 2019 16:26:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/1561164</guid>
    </item>
    <item>
      <title>Modeling Forming Limit in Low Stress Triaxiality and Predicting Stretching Failure in Draw Simulation by an Improved Ductile Failure Criterion</title>
      <link>https://trid.trb.org/View/1561160</link>
      <description><![CDATA[A ductile failure criterion (DFC), which defines the stretching failure at localized necking (LN) and treats the critical damage as a function of strain path and initial sheet thickness, was proposed in a previous study. In this study, the DFC is revisited to extend the model to the low stress triaxiality domain and demonstrates on modeling forming limit curve (FLC) of TRIP 690. Then, the model is used to predict stretching failure in a finite element method (FEM) simulation on a TRIP 690 steel rectangular cup draw process at room temperature. Comparison shows that the results from this criterion match quite well with experimental observations.       ]]></description>
      <pubDate>Fri, 20 Dec 2019 16:26:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/1561160</guid>
    </item>
    <item>
      <title>Replacing Press Hardenable Steel with 980 MPa Generation 3 Steel for Automotive Pillars</title>
      <link>https://trid.trb.org/View/1560554</link>
      <description><![CDATA[Press hardenable ultra high strength steel (UHSS) is commonly used for automotive components to meet crash requirements with minimal mass addition to the vehicle. Press hardenable steel (PHS) is capable of forming complex geometries with deep sections since the forming takes place at elevated temperatures up to 900 degrees Celsius (in the Austenitic phase). This forming process is known as hot-stamping. The most commonly used PHS grade is often referred to as PHS1500. After hot-stamping, it is typically required to have a yield strength greater than 950 MPa and a tensile strength greater than 1300 MPa. Most automotive design and material engineers are familiar with PHS, the hot-stamping process, and their capabilities. What is less known is the capability of 3rd Generation advanced high strength steels (AHSS) which are cold stamped, also capable of forming complex geometry, and are now in the process of, or have recently completed, qualification at most automotive manufacturers. This paper will show that U. S. Steel’s Generation 3 steel with 980 MPa minimum tensile strength (980GEN3) has comparable crash performance to PHS1500 when used for automotive body-in-white (BIW) Pillars in a sedan. This paper will also show that these 980GEN3 BIW Pillars can achieve the same complex geometry as PHS1500, that the springback can be predicted and controlled, and that prototype parts can be assembled into a vehicle build and physically crashed without issues. Furthermore, correlation between cold stamped 980GEN3 BIW Pillars and forming simulation results will also be discussed.       ]]></description>
      <pubDate>Thu, 27 Dec 2018 11:00:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/1560554</guid>
    </item>
    <item>
      <title>Investigation of Residual Stresses in Cold-Formed Steel Sections with
                    Nonlinear Strain-Hardened Material Model</title>
      <link>https://trid.trb.org/View/1560256</link>
      <description><![CDATA[In this article, forming residual stresses in cold-formed small-radius corner sections are analytically predicted with the consideration of the shift in the neutral axis and the nonlinear strain-hardened material model. The predicted forming stress results in the transverse direction show a trend of increased compressive residual stress in the outer surface and reduced tensile residual stress in the inner surface, as the corner radius-to-thickness ratio increases in small-radius bends. In the longitudinal direction, there is no significant change in the residual stress values observed in the inner and outer surfaces with respect to an increase in corner radius-to-thickness ratios. But a considerable decrease in compressive residual stress and an increase in tensile stress values are observed in the midsection areas, with an increase in the corner radius-to-thickness ratio. It is observed that the analytical peak compressive residual stress values are always higher than the experimental results. Also, the through-thickness residual stress from the numerical model is in close agreement with the analytical results. The magnitude of the maximum compressive stress in the inner half thickness is observed to be more than the magnitude of the maximum tensile stress in the outer half thickness of the corner section. The shift in the neutral axis towards the inner corner surface is much severe for lower corner radius-to-thickness ratio sections. The new approach provides a more accurate definition of initial conditions for further nonlinear structural behavior analysis of cold-formed structures.]]></description>
      <pubDate>Mon, 26 Nov 2018 16:53:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/1560256</guid>
    </item>
    <item>
      <title>Effect of Roughness on the Wear of Cold Forming Tools</title>
      <link>https://trid.trb.org/View/1461793</link>
      <description><![CDATA[The cost of any forged product for the automotive industry is highly influenced by the cost involved during the design and manufacturing of the forging tools. Ideally, these tools shall withstand a significant number of cycles, in order to divide their manufacturing cost in many parts as possible. There are several parameters that affect the wear behavior, and forging companies have different approaches to address the tribological issues. Moreover, a misunderstanding of these parameters may lead to an undesirable premature tool wear.         This work analyses the effect of roughness on the wear of cold forming tools. The adopted tribosystem is the second stage of a horizontal press and consists of a punch of M2 hardened steel in relative movement against a working piece of SAE 10B22 normalized steel. Fifteen punches were manufactured with three roughness levels and their wear was measured after 50.000 and 100.000 forging cycles. A 3D optical profiler and a Scanning Electronic Microscope (SEM) were used to access the surface characteristics of the punches before and after the production batches.       ]]></description>
      <pubDate>Tue, 20 Nov 2018 10:12:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/1461793</guid>
    </item>
    <item>
      <title>Section Idealization of Corrugated Thermoplastic Pipe in AASHTO Design</title>
      <link>https://trid.trb.org/View/1493176</link>
      <description><![CDATA[The AASHTO Load and Resistance Factor Bridge Design Specifications (AASHTO LRFD) thermoplastic pipe design method requires corrugated pipe local buckling resistance to be determined based on corrugation effective area. The effective area may be determined through calculations or physical tests on sections of pipe. When determined through calculations, effective area is based on individual corrugation element (e.g., crest, valley, web) slenderness following methods published by the American Iron and Steel Institute (AISI) for cold-formed steel design. Cold-formed steel members are rolled from constant-thickness steel sheet and have cross-sections divided into elements by distinct corners. In contrast, corrugated thermoplastic pipe cross-sections have variable geometries with non-uniform thickness, elements without distinct corners defining their ends, and elements that may be rounded or have other beneficial features such as intermediate ribs or stiffeners. Applying the calculation method requires idealization of corrugation elements into flat plates of representative clear width and thickness. As corrugation geometries have evolved with the increased use of thermoplastic pipe, there has not been a thorough review of appropriate methods of idealization to ensure current geometries meet the intent of the design method. This paper reviews the existing AASHTO LRFD effective area calculation method, information from background documents upon which the AASHTO LRFD method was based (NCHRP reports 438 and 631), and relevant information from the AISI Specification for the Design of Cold-Formed Steel Structural Members; identifies important concepts for cross-section idealization; and provides recommendations for idealization of corrugation members with curves and intermediate stiffeners.]]></description>
      <pubDate>Thu, 10 May 2018 09:21:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/1493176</guid>
    </item>
    <item>
      <title>Design Analysis for Origami-Based Folded Sheet Metal Parts</title>
      <link>https://trid.trb.org/View/1434002</link>
      <description><![CDATA[The manufacturing of Origami based sheet metal products is a promising technology, mostly in terms of reducing the tooling and process complexity. This procedure can also be called fold forming, as it depends on exclusively shaping the required geometry via sequence of bends. However, the design analysis and modeling of folded sheet metal products are not fully mature, especially in terms of determining the best approach for transferring the analysis from a three-dimensional (3D) to a two-dimensional (2D) context. This manuscript discusses the extension of the Origami technique to the fold forming of sheet metal products represented in modeling approach and design considerations for the topological variations, the geometrical validity, and the variance of stress-based performance. This paper also details the optimization metrics that were developed to reflect the design and manufacturing differences among the possible topological and geometrical options for a single part design. These metrics target five different optimization objectives: material utilization, cost, ease of manufacturability, ease of handling, and mechanical behavior estimation.]]></description>
      <pubDate>Thu, 05 Jan 2017 16:24:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/1434002</guid>
    </item>
    <item>
      <title>Analytical Solutions of Resilience Based on Tri-Parameters Constitutive Model under Different Cold-Forming Cases</title>
      <link>https://trid.trb.org/View/1433634</link>
      <description><![CDATA[Ti-alloy sheet is a high-modulus elastic-plastic material, about which the resilience in the cold-forming process is quite difficult to control. As a matter of fact, the procedure of cold-forming is composed of many cases such as tensile case and bending case. An expression of ultimate radius for bending-curvature is obtained based on tri-parameters elastic-plastic constitutive model. By classifying the cold-forming process, some typical cases of cold-forming are presented in this paper, and analytical solutions with a high precision of resilience for high-modulus elastic-plastic material such as Ti-alloy sheet under the different typical cases are obtained in this paper. The accurate analytical solutions of resilience for high-modulus elastic-plastic material presented in this paper will contribute to cold-forming process both in the mould-designing and optimizing of cold-forming procedure.       ]]></description>
      <pubDate>Thu, 05 Jan 2017 16:23:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/1433634</guid>
    </item>
    <item>
      <title>Pullout Strength of Steel Pins in Cold-Formed Steel Framing</title>
      <link>https://trid.trb.org/View/1316812</link>
      <description><![CDATA[Steel pins are an attractive and efficient alternative technology to screws when connecting cold-formed steel or other materials to cold-formed steel members. However, unlike screws, pins remain an essentially proprietary connection technology based on manufacturer claims of special pin shank design. As such, current cold-formed steel design standards and specifications do not include provisions for their direct use and designers have no simple, rational means for making informed design decisions beyond information provided by manufacturers. This paper reviews the current design model for screws and examines the basic tension pullout/withdrawal limit state of helical knurled steel pin connections for cold-formed steel thicknesses common in residential construction. Included in this paper is a determination of material properties using a nondestructive test method as an alternative to traditional methods for estimation of steel base metal thickness. A simple lower bound friction model is proposed for helical steel pins and the model is calibrated using data from 32 physical pin tests. The calibrated model is shown to provide an acceptable degree of reliability and safety consistent with that of screws in current cold-formed steel design standards and specifications.]]></description>
      <pubDate>Wed, 27 Aug 2014 10:54:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/1316812</guid>
    </item>
    <item>
      <title>Distortional Buckling of CFS Stiffened Lipped Channel Compression Members</title>
      <link>https://trid.trb.org/View/1313205</link>
      <description><![CDATA[The direct strength method (DSM) simplified the design of cold-formed steel (CFS) beams and columns compared with the traditional effective width method (EWM). In this paper, DSM equations for the distortional buckling (DB) strength are evaluated using the results of the experimental study on channel compression members with edge and intermediate stiffeners as well as nonlinear finite-element analysis (FEA) of the stiffened lipped channel compression members with various configurations, which fail after only DB. A total of 14 fixed-ended stiffened lipped channel compression members with intermediate stiffeners in both the web and flanges were tested, which failed after only DB. Further, additional data on the DB behavior is generated based on a parametric study using the nonlinear FEA, which was initially calibrated with the test data. A study on effect of parameters, such as the type of cross section, the dimensions of the cross section, the lip depth to flange width ratio (d/b), the web height to the flange width ratio (h/b), the yield stress (fy), end boundary condition (EBC), and the failure modes, shows that the nondimensional ultimate strength, expressed as the ratio of the ultimate strength to yield strength under compression, Pu/Py, is adequately addressed through the nondimensional DB slenderness, λd, alone as assumed in the DSM. The test and the analysis results show that the DSM equations generally evaluate the strength of stiffened lipped channel members under DB conservatively. Modifications to the DSM equations are suggested to evaluate the DB strength of stiffened lipped channel members more accurately.]]></description>
      <pubDate>Thu, 31 Jul 2014 09:15:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/1313205</guid>
    </item>
    <item>
      <title>Design of Built-Up Cold-Formed Steel Columns According to the Direct Strength Method</title>
      <link>https://trid.trb.org/View/1267640</link>
      <description><![CDATA[The direct strength method (DSM) is used in order to predict the axial compression capacity of innovative cross-section shapes for built-up columns from cold-formed steel (CFS) profiles. The proposed four composed shapes have been adapted in order to obtain members of increased strength-to-weight ratio. After excluding various buckling mechanisms from the columns response to compressive loads, highly stable members with reduced sensitivity to initial imperfections are obtained. DSM predictions are validated experimentally for the four built-up cross-section types. The investigation shows that DSM could easily be extended towards composed members if provisions for members sensitive to global-distortional buckling interaction are included in the method. The good agreement with experiments also indicates that the proposed built-up assemblies are reliable and can be integrated into everyday construction practice.]]></description>
      <pubDate>Thu, 21 Nov 2013 09:22:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1267640</guid>
    </item>
    <item>
      <title>Cold-Formed Steel Lipped Channel Columns Influenced by Local-Distortional Interaction: Strength and DSM Design</title>
      <link>https://trid.trb.org/View/1250640</link>
      <description><![CDATA[This paper deals with the ultimate strength and design of fixed-ended lipped channel columns experiencing local-distortional buckling mode interaction. First, the paper reports the results of an experimental investigation involving a set of 26 columns with several cross-section dimensions and yield stresses that were tested to determine their failure loads and also to provide experimental evidence of the occurrence of local-distortional mode interaction. These results consist of the column geometries, material properties, initial geometric imperfections, nonlinear equilibrium paths, and ultimate strength values. Then, after comparing the experimental column ultimate loads with the estimates provided by the current direct strength method (DSM) design curves against local and distortional failures, which clearly show that they lead to inaccurate and often very unsafe ultimate strength estimates, the paper presents and assesses the quality of DSM-based design procedures based on approaches providing nominal strengths against local-distortional and distortional-local interactive failures. Next, an in-depth comparison is made between all the experimental ultimate strength results available in the literature and their estimates provided by the preceding DSM design procedures. Finally, the paper closes with design considerations and recommendations, motivated by the conclusions drawn from this investigation.]]></description>
      <pubDate>Mon, 17 Jun 2013 14:16:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/1250640</guid>
    </item>
  </channel>
</rss>