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This research aims to use the finite element method to examine critical distress modes in the pavement layers due to changes in the structural properties brought upon by fire damage.

A full dynamic analysis is performed to replicate heavy vehicle axle wheel loads travelling over a pavement section.

Results show a 72 per cent decrease in the number of load repetitions which a fire-damaged pavement can experience before fatigue cracking of the asphalt. Further, there is a 51 per cent decrease in loading cycles of the subgrade before rutting of the fire-damaged system.

Fatigue of asphalt and deformation of subgrade from repeated vehicular loading are the most common failure mechanisms, and major attributors to pavement maintenance and rehabilitation costs. Pavement analysis has always been concentrated on evaluating deterioration under regularly occurring operational conditions. However, the impact of one-off events, such as vehicle petroleum fires, has not been evaluated for the effects on deterioration.

This paper aims to apply a pavement design by LEDFAA for a sample airport, and design results involving layer thickness, modulus and cumulative damage factor (CDF) achieved are shown in figures.

Finite element (FE) simulation is applied for sample airport pavement and based on results involving stress and strain, CDF amount is shown by using related equations. To analyze the accuracy of modeling, a comparison has been made between the values of ABAQUS and case study results at Denver International Airport (DIA).

The present study includes a comparison between the two conventional methods for runway pavement design. There is linear relation between layered elastic design (LED) and FE method results, so CDF rate achieved by the FE method is always smaller than the LED method. To assess the accuracy of the applied modeling with ABAQUS software, the validation was done using the deformations under the concrete slabs of DIA. The results are compatible with the results acquired from the case study, and the high accuracy of modeling was approved. This research shows that B-777 on rigid pavements and A-340-500/600 on flexible pavements have the most CDF contribution, among other aircrafts. Also, CDF rate for any aircraft in the LED method is higher than the FE method.

To assess the accuracy of the applied modeling with ABAQUS software, the validation was done using the deformations under the concrete slabs of DIA. The results are compatible with the results acquired from the case study, and the high accuracy of modeling was approved.

The present study aims to demonstrate the performance assessment of flexible pavement structure in probabilistic framework with due consideration of spatial variability modeling of input parameter.

The analysis incorporates mechanistic–empirical approach in which numerical analysis with spatial variability modeling of input parameters, Monte Carlo simulations (MCS) and First Order Reliability Method (FORM) are combined together for the reliability analysis of the flexible pavement. Random field concept along with Cholesky decomposition technique is used for the spatial variability modeling of the input parameter and implemented in commercially available finite difference code FLAC for the numerical analysis of pavement structure.

Results of the reliability analysis, with spatial variability modeling of input parameter, are compared with the corresponding results obtained without considering spatial variability of parameters. Analyzing a particular three-layered flexible pavement structure, it is demonstrated that spatial variability modeling of input parameter provides more realistic treatment to property variations in space and influences the response of the pavement structure, as well as its performance assessment.

Research is based on reliability analysis approach, which can also be used in decision-making for quality control and flexible pavement design in a given environment of uncertainty and extent of spatially varying input parameters in a space.

In many coastal areas where there are problematic soils, pavement construction on the soil is difficult because of the low shear strength and high consolidated. Also, given that the container terminals constitute more than 70% of the port area and as pavement in these areas is subject to heavy loads due to the long-term container storage, wheels of transport and movement equipment, the pavement must tolerate a distributed loading of at least 4 ton/m² in accordance with the type and weight of the containers imposed on the pavement. This study aims to investigate a variety of common pavement designs in coastal areas of southern Iran. The pavement type and characteristics of the subgrade layers are the same for each port; the thickness of different pavement layers is designed.

Due to problematic soil in the pavement subgrade, heavy and long-term container loading and the associated equipment, port pavement enjoys great importance.

The designed pavements are modeled by ABAQUS finite element software. The pavements are subject to a static load imposed by the corner casting container and resulted a distributed load 4 tons/m². The results from data analysis show that the concrete block pavements influenced by the containers static loads of 3%–20% have less vertical displacement on the subgrade than other pavements (rigid and flexible).

This paper is modeling 3 port pavement in Iran. Based on field evaluation and simulation actual loading on pavement.

Soil is an essential component of road construction and is used in the form of subgrade materials. It ensures the stability and durability of the road under adverse conditions; being one of the important parameters, poor judgment of the engineering properties of soil can lead to pavement failure. Geopathic stress (GS) is a subtle energy in the form of harmful electromagnetic radiation. This study aims to investigate the effect of GS on soil and concrete.

A total of 23 soil samples from stress zones and nonstress zones were tested for different engineering properties like water content, liquid limit, plastic limit, specific gravity and California bearing ratio. Two concrete panels were placed on GS zones, and their quality was monitored through nondestructive testing for a period of one year.

The result shows that the engineering properties of soil and pavement thickness are increasing in stress zones as compared with nonstress zones. For concrete panels, as time passes, the quality of the concrete gets reduced, which hints toward the detrimental effect of GS.

This research is a systematic, scientific, reliable study which evaluated subgrade characteristics thus determining the detrimental impact of the GS on soil and pavement thickness. On a concluding note, this study provides a detailed insight into the performance of the road segment when subjected to GS. Through this investigation, it is recommended that GS should be considered in the design of roads.

To explore the economical and reasonable semi-rigid permeable base layer ratio, solve the problems caused by rainwater washing over the pavement base layer on the slope, improve its drainage function, improve the water stability and service life of the roadbed pavement and promote the application of semi-rigid permeable base layer materials in the construction of asphalt pavement in cold regions.

In this study, three semi-rigid base course materials were designed, the mechanical strength and drainage properties were tested and the effect and correlation of air voids on their performance indexes were analyzed.

It was found that increasing the cement content increased the strength but reduced the air voids and water permeability coefficient. The permeability performance of the sandless material was superior to the dense; the performance of the two sandless materials was basically the same when the cement content was 7%. Overall, the skeleton void (sand-containing) type gradation between the sandless and dense types is more suitable as permeable semi-rigid base material; its gradation is relatively continuous, with cement content? 4.5%, strength? 1.5 MPa, water permeability coefficient? 0.8 cm/s and voids of 18–20%.

The study of permeable semi-rigid base material with large air voids could help to solve the problems of water damage and freeze-thaw damage of the base layer of asphalt pavements in cold regions and ensure the comfort and durability of asphalt pavements while having good economic and social benefits.

The ultra-thin white topping (UTW) is a cement concrete overlay of the thickness of 50–100 mm on bituminous concrete pavements with surface failures. This is a long-lasting solution without having short-term failures. This paper aims to design an ultra-thin cement concrete overlay using a developed critical stress model with sustainable concrete materials for low-volume roads.

In this research paper, a parametric study was conducted using the ultra-thin concrete overlay finite element model developed with ANSYS software, considering the significant parameters affecting the performance and development. The non-linear regression equation was formed using a damped least-squares method to predict critical stress due to the corner load of 51 kN.

The parametric study results indicate that with a greater elastic modulus of bituminous concrete, granular layer along with 100 mm thickness of concrete layer reduces the critical corner stress, interface shear stress in a significant way responsible for debonding of concrete overlay, elastic strains in the pavement further the concrete overlay can bear infinite load repetitions. From validation, it is understood that the non-linear regression equation developed is acceptable with similar research work done.

From the semi-scale experimental study, it is observed that the quaternary blended sustainable concrete overlay having a high modulus of rupture of 6.34 MPa is competent with conventional cement concrete overlay in terms of failure load. So, concrete overlay with sustainable materials of 100 mm thickness and higher elastic modulus of the layers can perform in a sustainable way meeting the environmental and long-term performance requirements.

Due to the increasing size and complexity of construction projects, construction engineering and management involves the coordination of many complex and dynamic processes and relies on the analysis of uncertain, imprecise and incomplete information, including subjective and linguistically expressed information. Various modelling and computing techniques have been used by construction researchers and applied to practical construction problems in order to overcome these challenges, including fuzzy hybrid techniques. Fuzzy hybrid techniques combine the human-like reasoning capabilities of fuzzy logic with the capabilities of other techniques, such as optimization, machine learning, multi-criteria decision-making (MCDM) and simulation, to capitalise on their strengths and overcome their limitations. Based on a review of construction literature, this chapter identifies the most common types of fuzzy hybrid techniques applied to construction problems and reviews selected papers in each category of fuzzy hybrid technique to illustrate their capabilities for addressing construction challenges. Finally, this chapter discusses areas for future development of fuzzy hybrid techniques that will increase their capabilities for solving construction-related problems. The contributions of this chapter are threefold: (1) the limitations of some standard techniques for solving construction problems are discussed, as are the ways that fuzzy methods have been hybridized with these techniques in order to address their limitations; (2) a review of existing applications of fuzzy hybrid techniques in construction is provided in order to illustrate the capabilities of these techniques for solving a variety of construction problems and (3) potential improvements in each category of fuzzy hybrid technique in construction are provided, as areas for future research.

Proper identification, allocation, and pricing of risks are critical to effective procurement and project delivery, particularly when contracts specify the intended performance instead of how the work is to be performed. This paper presents an overview of the sources of project risks when performance specifications are used for highway infrastructure procurement. The findings are based on a comprehensive literature review and interviews with subject-matter experts involved in developing performance specifications for highway infrastructure. The authors conclude that wider use of performance specifications in U.S. highway infrastructure construction requires a fundamental reassessment of risk allocation and pricing. Highway agencies and the contractors need to realign their respective organizational capabilities with the goal of using performance specifications as a facilitator of innovation, a goal that remains elusive after decades of applied research.