Advanced Modeling and Characterization of Civil Infrastructure Materials

The special collection on Advanced Modeling and Characterization of Civil Infrastructure Materials is available in the ASCE Library (https://ascelibrary.org/page/jenmdt/advanced_modeling_civil_infrastructure).

Civil infrastructure materials are subject to complex service conditions (mechanical, thermal, hydraulic, and chemical) because of loads and environmental interactions. It is critical to have a deep understanding of the material–structure–performance relationship in multiple scales (nano, micro, and macro) in order to design high-performance and durable civil infrastructure materials. This special collection is aimed at synthesizing the state-of-the-art development in advanced modeling and characterization of civil infrastructure materials. The multiscale and multiphysics characteristics of materials have been studied using various experimental methods and analytical-computational modeling techniques. The elastic-inelastic deformation and fracture (damage) behavior of materials have been investigated considering the heterogeneous nature of complex infrastructure materials.

The collection covers a wide range of civil infrastructure materials, including cement mortar, asphalt concrete, geopolymer, soil, glass fiber–reinforced polymer (GFRP), and functionally graded materials. Si et al. (2019) investigate the effects of internal curing on permeability of cement mortar using microscale X-ray computed tomography (μCT) characterization techniques and the Permeability Solver computational program to analyze the porosity, pore conductivity, and permeability of mortar mixtures. The results show that internal curing caused lower permeability. Rami et al. (2018) present a two-way linked multiscale method integrated with nanomechanical material characterization and cohesive zone fracture model to study highly heterogeneous cementitious material such as alkali-activated geopolymer composites. This integrated experimental-computational approach can simulate the multiscale behavior. It can also provide the core material properties such as micrometer-length-scale cohesive zone fracture properties, which it is not usually feasible to identify using conventional experimental tests. Islam et al. (2019) develop a chemomechanical (CM) model to capture the true failure process of cement-stabilized pavement subgrade under sulfate attack. A set of governing equations are developed and solved using the finite-element method. A unique expression for the moisture-dependent and heat-dependent diffusion coefficient of sulfate is proposed.

Ren et al. (2018) present an analytical solution to determine the effective thermal conductivity of an asphalt mixture based on the principle of minimum thermal resistance, considering morphological characteristics and thermal properties of each component. The morphological factor of coarse aggregate is deduced to quantify the contribution of the dispersed phase to the effective thermal conductivity of asphalt mixture. Chen et al. (2018) develop an algorithm for generating a three-dimensional (3D) heterogeneous microstructure of asphalt concrete based on random aggregate microstructure. The 3D aggregate shapes were generated with three two-dimensional (2D) projections randomly selected from the aggregate image database. The dynamic modulus of asphalt concrete is predicted with the generated heterogeneous microstructures and validated with experimental measurements. Darabi et al. (2019) evaluate the rutting performance of flexible airfield pavements using a viscoelastic-viscoplastic constitutive model for the asphalt layer and the Drucker-Prager-Cap model for the granular layer. A set of experimental tests including resilient modulus, cyclic triaxial, dynamic modulus, and flow number tests were used to fully calibrate the constitutive model of asphalt mixture. It is shown that the prediction of the permanent deformation of airfield pavements is significantly enhanced by using this strategy.

Song et al. (2019) investigate the pore pressure responses of overconsolidated (OC) soils during a piezocone penetration test (PCPT) based on a multiphysics numerical modeling technique. The influence of overconsolidation ratio (OCR) and hydraulic conductivity on the pore pressure responses of OC soils during PCPT was investigated by coupling the modified Cam-clay model and Darcy’s law. Lin et al. (2019) develop a micromechanics-based elastoplastic model to investigate inelastic behavior of functionally graded materials (FGMs) containing aluminum particles in high-density polyethylene (HDPE). The overall elastoplastic stress–strain response is established through homogenization of stress and strain fields. Guo et al. (2018) investigate seismic resistance of GFRP bolted joints with carbon nanotubes. Seismic tests performed on GFRP joints were conducted using displacement time histories extracted from structural analysis of a fiber-reinforced polymer (FRP) frame structure with GFRP bracing subjected to the 1940 El Centro earthquake. It is shown that the seismic resistance of GFRP bolted joints incorporating multiwalled carbon nanotubes increased by 44% compared with neat GFRP joints.

In summary, this collection covers different topics of recent developments in advanced modeling and characterization of civil infrastructure materials. Challenges in understanding and characterizing fundamental properties of civil infrastructure materials still exist and the integration of theory, experiment, and modeling methods is crucial. We trust that this collection will stimulate continued research in engineering mechanics to enable sustainable, functional, and more durable civil infrastructures.