This study examined a specific pavement study (SPS-6) in the long-term pavement performance (LTPP) program to evaluate the influences of the three slab fracturing techniques, namely, crack and seat (C&S), break and seat (B&S), and rubblization on the performance of rehabilitated PCC pavements with asphalt overlays. Fourteen projects using a variety of PCC rehabilitation treatments were identified from

In order to evaluate the macro-mechanical performance of asphalt mixture suffered from the sulphate–water–temperature–load coupling action, the self-designed asphalt mixture dynamic water–salt attack apparatus was adopted for the accelerated simulation of real service conditions in sulphate enrichment environment. Splitting test at room temperature and low temperature was conducted for assessing the

In this study, a total of four different mixes were prepared by partially replacing natural aggregates by Recycled Asphalt Pavement (RAP) in different proportions. The results showed that adding RAP to the mixture reduced the mechanical strength of the Roller Compacted Concrete (RCC) mixture. The best mechanical strength was obtained at 50% RAP replacement. To increase the mechanical strength of RCC

Artificial neural networks (ANNs) and Gb*-based regression models were used for the prediction of the dynamic modulus (|E*|) of South Carolina’s hot mix asphalt mixtures (HMAs) the majority of which contained recycled asphalt pavement (RAP). Models’ training and testing were done using a database that contained 1656 |E*| values from 93 HMA mixtures. Gb*-based models included the Hirsch, revised Hirsch

The use of reclaimed asphalt pavement (RAP) in road construction has become a common practice in the asphalt industry due to environmental and economic benefits. However, since RAP is an aged material, recycling agents are typically used to reduce the stiffness of the recycled asphalt mixture and make it less prone to cracking at high RAP contents. This study evaluates the effect of ageing and the

The present study reports on rheological properties of rejuvenated non-aged and aged bitumen samples with a pyrolytic product (PP) as a rejuvenator. Various experimental and numerical methods were used in order to investigate the addition of various concentrations of PP to aged and non-aged bitumen samples. It was confirmed that the application of PP as a rejuvenator to the aged bitumen has been successful

Upgrading, maintenance and rehabilitation of road infrastructure is expensive, especially in view of the growing scarcity and cost of suitable road building materials. In areas with high mica content and secondary minerals such as smectite in the natural materials, stabilisation with cement is not viable. The Council for Industrial and Scientific Research of South Africa has embarked on a research

To evaluate the contact slip behaviour of particle on compaction characteristics of the asphalt mixture, the relation between contact slip behaviour and compaction characteristic was analyzed. The specimen was molded by Superpave Gyratory Compactor, and the densification curve average slopes and densification energy index were adopted to evaluate the compaction characteristics of asphalt mixture. Based

ABSTRACT The road network in South Africa, particularly in urban areas, is experiencing a steady increase in traffic volumes and congestion. Speed has a significant effect on the response of flexible pavement systems to traffic loading. Truck tyre loads are more often analysed as a static load in order to simplify the computations, although in reality the pavement system is subjected to a dynamic load

This study investigated the effect of the different mineral fillers and concentrations, film thicknesses on the bituminous mastic bond strength (BMBS). Moreover, the self-healing capabilities of different bituminous mastic compounds were assessed, where the effects of two types of high modulus additives of RW plast S and RW elast E on the self-healing of bituminous mastic were evaluated. It was found

The effect of temperature on the meso-mechanical properties of each structural layer of the pavement was studied in this paper. Fitting standard indoor uniaxial compression tests, meso-scale parameters of the material were obtained. With the mesoscopic parameters of each structural layer, a two-dimensional discrete element model of the pavement was constructed. This discrete element model of the road

The National Cooperative Highway Research Program (NCHRP) Project 9-38 developed a method for estimating asphalt fatigue endurance limit (FEL) which employs bending beam fatigue (BBF) lives. Another project, NCHRP 9-44A, used BBF test data to formulate a healing-based FEL prediction model. Both procedures were evaluated in this study by utilising data from the National Center for Asphalt Technology

Determining the permissible amount of reclaimed asphalt pavement (RAP) in new pavement mixes is a design challenge for pavement practitioners due to the limited understanding regarding the interaction between the aged and unaged binders in these mixtures. In this study, the solubility related molecular interactions of blended binders comprising of aged-unaged fractions was evaluated using an extension

This study explores the development law of concrete internal stress and strain under rolling wheel loads. To do this, strain gauges are embedded in different positions inside concrete, and the stress and strain values at different positions inside the concrete are measured using the rolling fatigue test. A numerical model is established using COMSOL Multiphysics software, and the concrete internal

ABSTRACT A non-destructive testing method suitable for network-level pavement structural evaluation is the traffic speed deflectometer (TSD) test. However, the analysis of TSD measurements still needs a proper parameter back-calculation procedure, which requires an accurate and efficient forward calculation model. As a first step to solving this issue, a nonlinear spectral element model which can simulate

In Part I, a density driven damage mechanics (D3-M) approach and its application to model mechanical damage in concrete are presented. In this study, chemical and chemo-mechanical damage in concrete were modelled using the D3-M approach. It is proposed that reductions in local density in certain regions, created when concrete is subjected to chemical attack or coupled chemical-mechanical loading, result

Damage in concrete has been modelled using various approaches such as fracture mechanics, continuum damage mechanics and failure envelope theories. This study proposes a new approach to model the initiation of damage in concrete that addresses some limitations associated with the existing approaches. The proposed approach defines damage in terms of changes in the density of the material at the microscopic

Interlayer grid-reinforcement is one of the maintenance and rehabilitation (M&R) strategies often used to mitigate reflective cracking in hot-mix asphalt (HMA) overlays. However, there is no standardised laboratory test methodology for screening and selecting grid materials during the HMA overlay design stage. This laboratory study was conducted to comparatively evaluate, characterize, and quantify

The rutting resistance design of asphalt pavement is full of compromise between technology and economy because it is difficult to predict rutting evolution and distribution. In order to investigate the criterion of rutting, two forms yield function based on the Perzyna theory were contrasted and utilised in the finite element model. Besides, temperature and traffic load, the most important factors

Layered elastic theory is a familiar and commonly accepted framework for modelling and analysis of pavement systems. In actuality however, the suitability of the theory is challenged whenever the system includes a fragmented layer – which violates the inherent layer continuity assumption. This paper addressed the modelling challenge in these situations by introducing a fragmented layer into the accepted

In recent years, efforts have been made to utilise construction and demolition (C&D) wastes as an alternative material to natural quarried aggregates in the structural layers of railways and roads. Resilient modulus (Mr ) is one of the crucial design parameters used for the construction of roads and railways. Undertaking resilient modulus testing is expensive, time-consuming and complex. This study

Appropriate pavement maintenance is of great importance due to the increasing deterioration of pavements and limited resources. Nowadays, highway agencies face large-scale networks. The management of large-scale networks is a challenge concerning the computational complexity, which typically increases exponentially with the dimension of the network. Water cycle and genetic algorithms are utilised in

Reflective crack has been a major problem of asphalt overlay on existing concrete pavements. Joint or crack movements of concrete slab induce the concentrated stress in asphalt layer; thus producing this distress. Rainwater can then infiltrate into subgrade through this crack opening and the loss support is expected. In addition, the cohesive zone model has been steadily utilised to investigate the

Reclaimed asphalt pavement (RAP) is the deteriorated pavement material, containing aged binder and aggregates. A rejuvenator is normally added to the mixture to reduce its stiffness, by blending with the aged binder and changing the properties of the mixture. Therefore, it is necessary to have an insight into the microstructure of the RAP and rejuvenated RAP. In this study, waste engine oil (WEO),

Road safety is connected with pavement skid resistance which often triggers pavement maintenance issues. So far, many laboratory studies have been conducted trying to find a link between skid resistance and macrotexture. However, the findings cannot be extrapolated always in the field because of the multi-parametric nature of skid resistance. This triggered the present study that aims to identify key

Force chains are deemed as paths to transfer external loading in asphalt mixtures, and its properties difference can reflect the skeleton performances. In this study, the discrete element method (DEM) models of asphalt mixtures were established. Force chains characteristics of dense-suspended and dense-skeleton types asphalt mixtures were compared. Results indicate that force chains number of dense-suspended

Base layer stiffness, durability, permeability, and constructability are all significant factors that influence the performance of a concrete pavement system. The interaction between a concrete pavement and the underlying base layer(s) affects the response, including the distribution of stress, strain and deflection, of the pavement system to traffic loads and environmental conditions. Subbase stiffness

Fatigue cracking is the main type of distress in flexible pavements in Brazil. Numerical models that are based on viscoelastic continuum damage (VECD) theory can help to explain the damage evolution process in asphalt mixtures, thereby allowing the proper analysis of the fatigue phenomenon. This paper aims to characterise and verify the fatigue behaviour of four test sites constructed with dense asphalt

The effects of polymer modification on the durability of Polymer Modified Bitumens (PMBs) still remain relatively unclear due to partial understanding of the combined effects of ageing and loading on damage accumulation. This paper investigates the effects of laboratory ageing on the damage tolerance of cross-linked SBS and EVA modified bitumens measured using the Linear Amplitude Sweep (LAS) test

Reported in this paper is an evaluation of structural and functional performance of heavy duty and light duty pavements by addressing the effects of several factors on the rate of pavement deterioration. The sample used herein is a network of freeways and arterials from Victoria/Australia covering four road classes, namely M, A, B and C. The first two road classes represent heavy duty pavement and

The routine maintenance and rehabilitation of road pavement is vital to keep up with the service level and bearing capacity. However, the current problem is that, with the continuous increase of the scale of maintenance data, the traditional decision-making cannot satisfy the requirements in terms of accuracy and efficiency. The objectives of this paper were to improve the accuracy and efficiency of

ABSTRACT The mechanical performance of asphalt mixtures with high air void content – like Permeable Friction Courses (PFC) – is significantly affected by climate-related processes. Previous studies have demonstrated that ravelling (i.e. the loss of aggregates from the surface of the PFC) is related to the quality of the stone-on-stone contacts within the microstructure of these mixtures. Since the

Microsurfacing is a mixture of aggregates, cement, bitumen polymer emulsion (BPE), filler, water and chemical additives. In BPE that is a combination of bitumen, emulsifier, hydrochloric acid, water and liquid polymer, the type and amount of emulsifier affect its performance. The aim of this study is to investigate the performance characteristics of microsurfacing made by BPE with different percentages

A rapid and reliable method to detect the activation of contraction joint cracks is needed to assess the effectiveness of sawcut depth and timing on new concrete pavements and for forensic investigation. A one-sided ultrasonic measurement technique is presented that detects the existence of a contraction joint crack, which is not visible from the concrete slab surface. A multi-sensor ultrasonic array

This paper presents a fuzzy logic-based deterioration prediction models for gap and open-graded asphalt surfaces when both dynamic loading and shallow flooding coincide. The impact of aggregate size, load frequency, compaction levels, and environmental conditions was evaluated in a controlled laboratory testing to measure cracking and rutting performance of each mixture. A set of fuzzy logic was developed

Ungrooved stone mastic asphalt (SMA) provides an alternate to grooved dense graded asphalt (DGA) as a runway surface. To be verified as suitable in this application, SMA must provide similar or better asphalt surface performance, compared to DGA, and must achieve regulated aircraft skid resistance requirements. A pilot runway resurfacing project provided the basis for this laboratory and field comparison

In Korea, the transverse tining method has been applied to the surface texture of concrete pavements as it provides excellent skid resistance that improves road safety. However, transverse tining produces higher noise levels of about 4–5 dB(A) compared to asphalt pavements. Accordingly, exposed aggregate concrete pavement (EACP) is introduced since the low tyre-pavement noise and long-term skid resistance

The deteriorating condition of infrastructure, combined with fiscal limitations experienced by many agencies, necessitates increased service life of bridges. Maintenance and preservation methods such as overlays and sealers have been known to protect bridge decks from deterioration, while also extending a bridge’s service life. It is important to understand the characteristics of various overlay types

ABSTRACT In this study a comparative life cycle assessment (LCA) was conducted according to a ‘cradle-to-laid’ approach to evaluate the potential environmental impacts related to the use of recycled concrete aggregates (RCAs) as a partial replacement of coarse natural aggregates in the production of Hot Mix Asphalt (HMA). Specifically, three percentages of RCA replacements were analyzed: 15, 30 and

Cracks in rigid pavements are a frequent and critical problem, which needs to be assessed to avoid deterioration and provide comfort and security. Control of damage requires the evaluation of cracks width and depth. Several laboratory tests were used in order to determine the ability of Ground Penetrating Radar (GPR) in the evaluation of damage under different controlled conditions. Those tests were

In recent years, crumb rubber (CR) has become an attractive option to modify bitumen. In this research, a set of Dynamic Shear Rheometer (DSR) tests were used were used to gauge the effect of two types of CR on different rheological and mechanical properties of CR bitumen (CRB). To achieve this goal, temperature and frequency sweep tests were conducted on three CRB and one penetration 50/70 reference

International Roughness Index (IRI) is a key parameter in pavement performance evaluation. This study investigates developing a reliable prediction model that can be used to estimate IRI of rigid pavements using innovative machine learning techniques. Optimally Pruned Extreme Learning Machine (OP-ELM) and Wavelet analysis are integrated to improve the OP-ELM results and design a novel hybrid Wavelet-OPELM

This paper describes the elastic tire–pavement tractive rolling contact, by means of a semi-analytical method, in order to analyse top-down cracking. The model includes the actual tire profile and assumes the tyre to be elastic, linear and homogeneous, as modelled by an equivalent Young's modulus. The pavement is modelled as a half-space layer composed of asphalt concrete acting as a homogeneous elastic

Recycled waste materials are increasingly being used as low carbon construction materials in civil infrastructure works, as recycled materials have significant carbon savings compared with virgin quarried materials. In this research, the stiffness and modulus of rupture properties of crushed rock (CR) blended with recycled glass (RG) were evaluated. The engineering properties of the four cement-treated

Increasing road construction activities in Nigeria has led to increased demand for lateritic soil (LS), whose properties vary from one location to another, and. The properties of some of this laterite deposits along road alignment can be improved to enable it withstand traffic loads. This paper presents results of the laboratory evaluation of LS stabilised with oil palm fibre ash and cement blends

Currently, the bending beam rheometer (BBR) test is the standard method for evaluating the low-temperature performance grade (PG) of asphalt binders. Despite its use, there are limitations with the BBR test with respect to the amount of asphalt binder needed for test specimens, the relative difficulty in preparing specimens, and the overall testing efficiency. On the contrary, the dynamic shear rheometer

The film thickness of asphalt mortar, which is a mix of binder and fine mineral aggregates, has been considered as an important indicator for assessing the durability of asphalt mixture. This study proposes a novel method to characterise distribution of mortar film thickness in asphalt mixture through image processing techniques. Four asphalt mixtures with unmodified and modified binders were produced

The use of a reinforcing fibre in porous asphalt (PA) is a common practice to improve PA’s homogeneity and durability. This study developed a new type of fibre-shaped reinforcement element from cured carbon fibre composite materials (CCFCMs), which were collected from the waste stream of an aerospace manufacturing process. One control PA without CCFCMs and three PAs, which are reinforced by Fine CCFCMs

Studying the hydroplaning behaviour is crucial for enhancing the safety of aviation during the landing stage. Due to the special nature of the aviation field, such as high aircraft velocity, wheel load and operating frequency, accurate numerical simulation is considered an effective method for investigating the tire hydroplaning behaviour. In this study, a fluid–solid coupling model was established

This research recommends a mathematical modelling approach to determine flow time (FT). The scope of the work includes the collection and analysis of the static creep test data for asphalt mixtures produced using two different nominal maximum aggregate size (NMAS) values and two base binder grades. Modifiers of styrene butadiene styrene (SBS), polyphosphoric acid (PPA) and combination of them are selected

In Jordan, three major steel-manufacturing factories dump their by-product, recycled steel, randomly in open areas creating environmental hazards. This study intended to evaluate the effectiveness of using a By-product Recycled mill Scale (BRS) in improving the geotechnical properties of high-plastic subgrade soil. The efficacy of the BRS was judged by the improvement in the consistency limits, compaction

The purpose of this paper is to develop a multi-physical tyre model, which can take into account the influence of temperature and macro-texture of the road surface. The aim is to contribute to a better understanding and modelling of the tyre–road pavement interaction. This tyre–road interaction model can be used for friction estimation as well as rolling resistance estimation. Indeed, tyre–road friction

The influence of hydrated lime on moisture susceptibility of asphalt mixture was assessed using a combination of surface energy measurements and modified saturation ageing and tensile stiffness test. Four aggregate types, which are commonly used for manufacturing asphalt mixtures in the UK have been selected. These aggregates were from various rocks across the UK which includes felsic intrusive, calcite

Research has been done to obtain a Porous Concrete (PC) mixture capable of bearing heavy traffic loads while maintaining sufficient air voids (AV) to percolate water into the ground. This research aims to establish several design parameters in PC mixture dosage in order to generate a multi-criteria methodology that helps to obtain a final product, which is beneficial for both citizens and environment

This study presents the analytical models to predict the compressive strength of roller-compacted concrete pavement (RCCP) containing steel slag aggregate and fly ash. Based on the experimental results, three models were established in this study including multiple regression analysis (MRA), artificial neural networks (ANN) and fuzzy logic (FL). In the RCCP mixtures, cement was partially substituted

The use of concrete overlays has long been recognised as a cost-effective pavement maintenance and rehabilitation strategy. However, the long-term performance of various types of concrete overlays has not been fully investigated since there has not been enough performance data available to conduct such an evaluation. Concrete overlays have been regularly constructed on Iowa roadways since the late

Skid resistance is a key factor in road safety. Surface friction characteristics of roads are dependent on the microtexture and macrotexture of the surface. The decay of skid resistance with time is a function of traffic level and aggregate characteristics. This study developed predictive models for skid resistance of asphalt pavements and seal coat surfaces. The researchers examined the surface friction

The cumulative permanent strain of subgrade soils plays an important role in the pavement structure design and long-term pavement performance maintenance. In Southern China, the hot and humid climate increases the risk of becoming a saturated condition for subgrade soils. The saturated subgrade soils will generate significant cumulative permanent strain under long-term cyclic loading compared with

Rural roads play a pivotal role in facilitating connectivity for the rural communities by providing access for their economic and social needs. Due to lack of funding and other resources, maintenance decision making is often done in an ad-hoc and subjective manner. Moreover, the inability to collect extensive data as needed to run most pavement management systems and technical expertise required has

Assessment of the pavement condition plays a significant role in pavement maintenance and driving comfort enhancement. Current evaluation methods primarily employ manual weights according to the geometric appearance of the distress, which makes it difficult to assess its depth or impact on passengers’ experience. This paper proposes a data fusion-based method for pavement distress evaluation, which