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    <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" />
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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>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>Analysis and Optimization of Pavement Resilience</title>
      <link>https://trid.trb.org/View/1572475</link>
      <description><![CDATA[Infrastructure resiliency has become an important element to assure community recovery after unexpected events, and can be achieved through strategies that range from operation optimization to new material development. This paper focuses on resiliency in the context of pavement damage mitigation by addressing, from a theoretical standpoint, layered pavement resistance to specific dynamic loads and, thus, begins to formalize a theoretical framework for a more detailed analysis of such events. The performance of layering strategies and materials are first evaluated through relatively simple one-dimensional (1D) stress wave transmissivity analyses. Secondly, three-dimensional (3D) high-fidelity finite elements models that represent full-scale layered pavement systems, which were validated and verified against relevant experimental data presented in the literature by others, are implemented. The 1D results indicate that the methodology can serve the valuable purposes of evaluating potential layering schemes and constitutive models; the 3D approach demonstrates that engineered layering schemes mitigate the extent and magnitude of damage to pavements that are subjected to extreme dynamic loading.]]></description>
      <pubDate>Sat, 02 Mar 2019 15:41:12 GMT</pubDate>
      <guid>https://trid.trb.org/View/1572475</guid>
    </item>
    <item>
      <title>Towards an understanding of the structural performance of future electrified roads: a finite element simulation study</title>
      <link>https://trid.trb.org/View/1566746</link>
      <description><![CDATA[Nowadays, many novel technologies are under investigations for making our road infrastructure function beyond providing mobility and embrace other features that can promote the sustainability development of road transport sector. These new roads are often referred to as multifunctional or ‘smart’ roads. Focus in this paper is given to the structural aspects of a particular smart road solution called electrified road or ‘eRoad’, which is based on enabling the inductive power transfer technology to charge electric vehicles dynamically. Specifically, a new mechanistic-based methodology is firstly presented, using a finite element simulation and an advanced constitutive model for the asphalt concrete materials. Based on this, the mechanical responses of a potential eRoad structure under typical traffic loading conditions are predicted and analysed thoroughly. The main contributions of this paper include thus: (1) introducing a new methodology for analysing a pavement structure purely based on mechanistic principles; (2) utilising this methodology for the investigation of a future multifunctional road pavement structure, such as an eRoad; and (3) providing some practical guidance for an eRoad pavement design and the implementation into practice.]]></description>
      <pubDate>Sat, 17 Nov 2018 17:17:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/1566746</guid>
    </item>
    <item>
      <title>Filled Rubber Isolator’s Constitutive Model and Application to
                    Vehicle Multi-Body System Simulation: A Literature Review</title>
      <link>https://trid.trb.org/View/1560143</link>
      <description><![CDATA[
                
                Rubber elements present highly nonlinear mechanical properties affected by
                    frequency and amplitude of excitation, prestrain and temperature, etc. Finite
                    element (FE) models and lumped parameter models can be distinguished in the
                    development of constitutive models of rubbers. Based on the concept of overlay
                    model, different kinds of viscoelastic, or frequency-dependent models, and
                    elastoplastic/friction, or amplitude-dependent models, are compared in terms of
                    their modelling approach, parameters identification process and applications.
                    Prestrain-dependent models and temperature-dependent thermo-mechanical models
                    are also reviewed, including some special models which are not based on the
                    concept of the overlay model. Experimental and computational studies of
                    cylindrical bushings subjected to coupled deformation modes are analyzed and
                    discussed. It is the hope that this literature review work can help clarify and
                    guide the future research and development direction about rubber constitutive
                    modelling.
            ]]></description>
      <pubDate>Mon, 22 Oct 2018 16:27:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/1560143</guid>
    </item>
    <item>
      <title>Effect of the Realistic Tire Contact Pressure on the Rutting Performance of Asphaltic Concrete Pavements</title>
      <link>https://trid.trb.org/View/1512738</link>
      <description><![CDATA[The effect of different configurations of normal contact stresses on the rutting performance of asphalt concrete overlays on a soft and stiff Crushed Aggregate Base (CAB) layer is investigated. A three-dimensional (3-D) finite element model of a pavement structure is generated. The effect of different types of simplified normal contact stresses and a realistic 3-D normal stress on the rutting performance is investigated. Since the failure mechanism of asphaltic materials at high temperature is mainly related to the flow of the material, the viscoelastic and viscoplastic constitutive relationships coupled with the hardening-relaxation mechanisms are utilized to represent the behavior of asphalt concrete layer. This constitutive relationship is part of the PANDA (Pavement Analysis using Nonlinear Damage Approach) model developed by the authors and their collaborators. As the result of simulation, the magnitude of the rut depth on the asphalt concrete layer is generally determined to be inversely proportional to the stiffness of the CAB layer, and the rut depth on the asphalt concrete layer under the realistic 3-D normal stress is about 1.5 times greater than the rut depth under uniformly distributed normal stress.]]></description>
      <pubDate>Mon, 25 Jun 2018 13:49:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/1512738</guid>
    </item>
    <item>
      <title>Damage Constitutive Models of Concrete under the Coupling Action of Freeze–Thaw Cycles and Load based on Lemaitre Assumption</title>
      <link>https://trid.trb.org/View/1510975</link>
      <description><![CDATA[In cold environments, concrete structures are subjected to a combined action of load, freeze–thaw cycles, and salt attack. The performance degradation of some concrete structures in such areas is serious, thus shortening their service life. In this study, a macro-mesoscopic coupling damage model was established to determine the durability of concrete under the coupling action of freeze–thaw cycles and load based on the Lemaitre strain equivalent assumption. Meanwhile, an indoor accelerated test was conducted to verify the rationality of the model. Results indicated that the damage in different kinds of concrete under freeze–thaw cycles and load can be predicted by the theoretical model. The structural coupling damage was determined by the meso-damage caused by the freeze–thaw cycles and the macro-damage caused by the applied load, which showed a nonlinear superposition relationship. The evolution laws of coupling damage were entirely different because of the freeze–thaw cycles and strain. The coupling damage and peak strain increased with the increase in number of freeze–thaw cycles but the variation range of damage and peak stress decreased. The peak strain can be the critical point of the coupling damage when the number of freeze–thaw cycles was constant. The growth of coupling damage was not significant before the peak strain. When the deformation approached the peak strain, the coupling damage increased considerably, and the concrete was destroyed rapidly.]]></description>
      <pubDate>Fri, 22 Jun 2018 16:40:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/1510975</guid>
    </item>
    <item>
      <title>Study on Constitutive Relationship of Steel Fiber–Reinforced Concrete Based on Four-Point Bending Test</title>
      <link>https://trid.trb.org/View/1495354</link>
      <description><![CDATA[The bending performance of concrete reinforced with different steel fibers (shape and strength) and volume fractions was evaluated based on the four-point bending test. Based on the existing multi-line type constitutive model, the concept of fracture zone was introduced, and the method of determining the tensile constitutive relation of steel fiber reinforced concrete based on the result of bending test was established. The difference between the experimental curve and the load-deflection curve obtained when the constitutive model was in the form of two-line type, three-line type and four-line type was compared and analyzed. The results show that the incorporation of steel fiber can improve the tensile, residual strength and toughness of concrete, among which the effect of ultra-high-strength steel fiber was better, the ordinary steel fiber was second, and the mill cutting steel fiber was weaker. Besides, there was little difference in prediction with the four-line type and three-line I type constitutive model, and the three-line I type constitutive model can be used when the prediction requirements are not demanding. However, the fitting accuracy in small deflection range was slightly worse when using the three-line II type and two-line type model, and it was not recommended for precise calculations. In addition, for the existence of the short-term load drop area in the load-deflection curve, the four-line should be modified to get better fitting results.]]></description>
      <pubDate>Tue, 06 Feb 2018 18:14:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/1495354</guid>
    </item>
    <item>
      <title>Development of subgrade Mᵣ constitutive models based on physical soil properties</title>
      <link>https://trid.trb.org/View/1489070</link>
      <description><![CDATA[Resilient modulus (Mᵣ) is a measure of the stiffness for geomaterials under cyclic loading. The evaluation of Mᵣ for fine-grained subgrade soils can be challenging due its sensitivity to variation in moisture content and stress state. Additionally, pavement subgrades often exist under unsaturated conditions, which further complicates the evaluation of Mᵣ. For unsaturated soils, matric suction needs to be incorporated into Mᵣ models to accurately capture the stress state of the soil. The importance of accurate Mᵣ evaluation in pavement design has long been recognised; however, laboratory measurement of Mᵣ remains inaccessible to most practitioners due to the specialised equipment and personnel needed to evaluate Mᵣ in the laboratory. This study provides a method to evaluate the Mᵣ value from simple soil physical properties that also account for the effects of moisture variation and stress state without needing to perform laboratory repeated load triaxial (RLT) tests. A laboratory investigation, which included performing RLT tests to obtain Mᵣ values at different moisture contents and measuring soil water retention curves (SWRC), was conducted on four different fine-grained soils. A statistical regression analysis was performed to develop prediction models for evaluating regression coefficients (i.e. k1, k2, k3) of Mᵣ constitutive models based on simple and unique soil physical properties (e.g. degree of saturation, activity parameter). The statistical prediction models were developed for two different constitutive Mᵣ models, one of which accounted for the stress state of unsaturated soils by incorporating matric suction. Results of this study show good agreement between the measured and predicted Mᵣ values obtained utilising the statistical regression models.]]></description>
      <pubDate>Wed, 29 Nov 2017 09:29:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/1489070</guid>
    </item>
    <item>
      <title>Effect of constitutive models on the seismic response of an SMA-LRB isolated highway bridge</title>
      <link>https://trid.trb.org/View/1480585</link>
      <description><![CDATA[Shape memory alloy wire-based lead rubber bearings (SMA-LRBs) are new types of smart isolators. They possess superior self-centering property with unique hysteresis and energy dissipation capacity compared to traditional elastomeric isolators. Although the hysteresis behavior of such elastomer can be approximated by bilinear kinematic hardening rule, the results become erroneous. Hence, a new constitutive model was developed for simulating the behavior of such smart bearings. Here, the developed model has been implemented in OpenSees, a finite element software. In order to verify the accuracy of this implemented model, the seismic behavior of a three-span continuous highway bridge isolated by SMA-LRBs is evaluated under different earthquake excitations. Results revealed that unlike the bilinear kinematic hardening model, the new model can precisely capture the self-centering property of SMA-LRBs. Findings show that SMA wires can satisfactorily reduce the shear strain demand in LRBs and restrain the deck displacement by increasing the effective stiffness of elastomeric isolator. As a result, the possibility of failure in the bearings, and unseating problem in the bridge deck can be effectively reduced. Results also show that due to the superior energy dissipation capacity of SMA-LRBs, such smart bearings can considerably improve the seismic performance of piers in terms of base shear.]]></description>
      <pubDate>Mon, 25 Sep 2017 14:10:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/1480585</guid>
    </item>
    <item>
      <title>Modelling asphalt concrete viscoelasticity with damage and healing</title>
      <link>https://trid.trb.org/View/1480029</link>
      <description><![CDATA[The behaviour under load of asphalt concrete (AC) was viewed as additively separable into viscoelastic and viscoplastic components, and the study focused on modelling the pre-peak response of the viscoelastic part under constant temperature conditions. Non-linear viscoelastic behaviour was first exposed in several test modes, and a constitutive theory was subsequently offered – potentially capable of capturing and reproducing the observations. The modelling was based on replacing applied stresses in the linear convolution formulation with effective stresses; it included a mechanism for simulating the following effects: (i) short-lasting damage, (ii) long-lasting damage, (iii) stiffening under compressive conditions and (iv) healing during recovery intervals. As an initial validation effort, the model’s reproducibility was assessed by calibration to a uniaxial compression experiment consisting of both small and medium strain levels. Next, the calibrated model was employed to forecast small-strain behaviour in a standard complex modulus test. The simulated results qualitatively agree with recently reported findings that challenge the existence of a linear viscoelastic domain for AC.]]></description>
      <pubDate>Mon, 14 Aug 2017 12:41:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/1480029</guid>
    </item>
    <item>
      <title>Mechanistic procedure for parameter determination of multiplicative decomposition based constitutive models</title>
      <link>https://trid.trb.org/View/1460912</link>
      <description><![CDATA[By exploiting the Clausius–Planck local energy dissipation inequality, a large strain, three-dimensional constitutive model has been developed for the monotonic and cyclic response prediction of various asphaltic materials. The model consists of a Zener non-linear, visco-elastic component acting in series with a stress dependent viscous component. A novel computational scheme has been developed for solution of the coupled system of equations expressing the interdependent response of these two in series components. An explicit, mechanistic, parameter determination procedure is presented for the laboratory determination of all necessary model parameters. Examples of model parameter determination and utilisation for prediction of the response of a recycled asphalt mix and a stone mastic asphalt mix are presented.]]></description>
      <pubDate>Sun, 30 Apr 2017 17:08:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/1460912</guid>
    </item>
    <item>
      <title>Behaviour of a Segmental Tunnel Lining Under Seismic Actions</title>
      <link>https://trid.trb.org/View/1423034</link>
      <description><![CDATA[Full dynamic analyses that follow a coupled approach for the soil-structure interaction, provides satisfactory interpretation of non-linear boundary problems during earthquakes. This paper illustrates the results of a numerical study aimed at modelling the performance of continuous and segmental linings of shallow tunnel under seismic loading. A set of 3D finite-element full dynamic analyses have been carried out, calibrated on the experimental results of a centrifuge test on a model tunnel in a dense dry sand layer subjected to transversal dynamic loading. The numerical study was extended to model and compare the seismic demand of a continuous and a segmental reinforced concrete lining, including the effect of the excavation process on the pre-seismic conditions and the influence of different input signals. The results show that even in rather simple ground conditions, a suitable constitutive model for soil is needed to capture the effect of soil-lining interaction during and after the seismic event.]]></description>
      <pubDate>Mon, 19 Sep 2016 12:42:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/1423034</guid>
    </item>
    <item>
      <title>Development of a New Constitutive Model for Analysis of RC Elements Retrofitted With FRP</title>
      <link>https://trid.trb.org/View/1359683</link>
      <description><![CDATA[Fiber-reinforced Polymer (FRP) started to find its way as an economical alternative material in civil engineering from the early 1970s. The behavior and failure modes for FRP composite structures were studied through extensive experimental and analytical investigations. While research related to the flexural behavior of FRP strengthened elements has reached a mature phase, studies related to FRP shear strengthening is still in a less advanced stage. In all proposed models to predict the shear capacity, the constitutive behavior of concrete and FRP was described independently. The true behavior, however, should account for the high level of interaction between the two materials. In this research, new constitutive relations for FRP-strengthened reinforced concrete elements subjected to pure shear are developed. In order to generate these relations, large-scale tests of a series of FRP strengthened reinforced concrete panel elements subjected to pure shear are conducted. The University of Houston is equipped with a unique universal panel testing machine that was used for this purpose. These constitutive laws are implemented into fiber-based finite element models to predict the behavior of externally bonded FRP strengthened beams. The newly developed model proved to provide a good level of accuracy when compared to experimental results.]]></description>
      <pubDate>Tue, 28 Jul 2015 15:56:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/1359683</guid>
    </item>
    <item>
      <title>Evaluating Influence Depth of Light Weight Deflectometer through Finite Element Modeling</title>
      <link>https://trid.trb.org/View/1356788</link>
      <description><![CDATA[The light-weight deflectometer (LWD), which is the portable version of the common falling weight deflectometer (FWD), has been gaining popularity due to the ease of use and familiarity of pavement community to the deflection-based concepts. LWD imparts a pulse load to the surface of a soil layer through a circular plate to measure the soil surface deflection and to estimate the effective modulus of the underlying system. An extensive finite element modeling was performed to study the mechanism of two common types of LWDs during quality control of unbound pavement materials. The performance of the LWDs was evaluated under various loading conditions, different plate sizes and a diverse range of geomaterial properties. The influence depth was studied using both stress and strain criteria. The nonlinear constitutive model parameters seem to have significant influence on the measured influence depth of both devices. However, different functional properties of each device were found to be the source of variations in the results.]]></description>
      <pubDate>Mon, 29 Jun 2015 15:52:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/1356788</guid>
    </item>
    <item>
      <title>Evaluation of Resilient Modulus Prediction Models for Cohesive and Noncohesive Soils</title>
      <link>https://trid.trb.org/View/1356787</link>
      <description><![CDATA[Geomaterials are often in unsaturated condition during their service life and their resilient modulus is influenced by several factors including moisture content, density, void ratio, plasticity, etc. There are various constitutive models to predict the nonlinear resilient modulus of unbound materials as a function of the aforementioned factors—particularly moisture and stress states based on empirical equations or theoretical unsaturated soil mechanics concepts. In this study, seven existing constitutive models and two predictive models were evaluated using eight different soil databases with different properties including cohesive and non-cohesive soils. The constitutive models were calibrated based on the data at optimum moisture content and maximum dry density. Consecutively, the calibrated models were used to predict the resilient modulus at other moisture or density conditions. The models were compared in terms of their rationality, accuracy of prediction, and applicability to the widest range of soils.]]></description>
      <pubDate>Mon, 29 Jun 2015 15:52:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/1356787</guid>
    </item>
    <item>
      <title>Reduction of Bridge Construction and Maintenance Costs through Coupled Geotechnical and Structural Design of Integral Abutment Bridges</title>
      <link>https://trid.trb.org/View/1335454</link>
      <description><![CDATA[Elimination of expansion joints in the superstructure of integral abutment bridges offers the advantage of reducing the initial and life cycle costs of the structure. However, such elimination may have an adverse effect on the displacement demand at the pile-abutment connection and on the earth pressures on the abutment wall due to the thermal expansion/contraction cycles of the bridge. These adverse effects have resulted in regulations that impose restrictions on the maximum length and skew angle of integral abutment bridges. This research consisted of a deep analysis of the problem by considering soil-structure interaction. The approach was multifaceted as it included experimental and numerical analysis. Upon calibration and verification of the constitutive model, it was used as part of a parametric analysis to provide recommendations for the design limits of integral abutment bridges. The analysis results showed that active state earth pressure is reached after the first contraction cycle. The displacement demand on piles is a function of the abutment wall displacement. Larger displacement demand of the pile at the acute corner when compared to the obtuse corner was observed during expansion and contraction cycles. The inflection point of the piles deformed shape was found to be at relatively shallow depth. Concrete shrinkage and sequence of loading affected significantly the displacement demand of the supporting piles, lower displacement demand of piles during the expansion cycle and larger displacement demand during contraction cycles. The analysis showed that a 500 ft bridge with 60° skew will provide acceptable long term performance.]]></description>
      <pubDate>Mon, 22 Dec 2014 19:13:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/1335454</guid>
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