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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.

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.

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.

A single system to replace the four existing methods has been proposed for world‐wide use; if adopted by the Council, all users will benefit—airport and aircraft operators and aircraft manufacturers …

The Thirteenth Wright Brothers Lecture delivered by Mr A. E. Russell of The Bristol Aeroplane Co. Ltd. before the Institute of the Aeronautical Sciences in New York on December 17, 1949. The problem of flutter is one of the earliest associated with flying but has, until comparatively recent times, been solved merely by solving the problem of strength coupled with the tactical distribution of lead weights. We are now becoming quite proficient at solving the problem of strength and are disturbed if our test structures do not fall within 1 or 2 per cent of the design loads (however arbitrary these loads may be). At the same time this steady refinement of design has resulted in a reduction of structure weight for given design loads. Refinement of structural design has reduced the stiffness of the structure and this, coupled with a steady increase of cruising speeds, has brought the flutter problem into its present prominence.

The purpose of this study is to numerically model the rigid pavement resting on Pasternak soil and to examine its various response parameters and stress resultants like deflection, rotation, bending moment and shear force when subjected to aircraft loading.

The study is carried out using a one-dimensional (1D) beam element based on the finite element method (FEM). Each node in this element has three rotational and three translational degrees of freedom (DOF). MATLAB programming is used to perform the static analysis of rigid pavement.

Response parameters and stress resultants of the rigid pavement were determined. The FEM used in this work is validated by two closed-form numerical examples, which are in great accord with previous research findings with a maximum divergence of 4.64%, therefore verifying the finite element approach used in the current study. Additionally, various parametric studies have been carried out to study the variations in response parameters and stress resultants.

The investigation at hand focuses exclusively on the static analysis of the pavement. The study constraints pertaining to the preliminary design phase of rigid pavements are such that a comprehensive three-dimensional finite element analysis is deemed unnecessary.

As limited previous research had performed the static analysis of rigid pavement on Pasternak foundation with 6 DOF. Furthermore, no prior study has done seven separate parametric investigations on the static analysis of rigid pavement.

The purpose of this study is to numerically model the rigid pavement resting on two-parameter soil and to examine its modal parameters.

This study is carried out using a one-dimensional beam element with three rotational and three translational degrees of freedom based on the finite element method. MATLAB programming is used to perform the free vibration analysis of the rigid pavement.

Cyclic frequency and their corresponding mode shapes were determined. It has been investigated how cyclic frequency changes as a result of variations in the thickness, span length of pavement, shear modulus, modulus of subgrade, different boundary conditions and element discretization. Thickness of the pavement and span length has greater effect on the cyclic frequency. Maximum increase of 29.7% is found on increasing the thickness, whereas the cyclic frequency decreases by 63.49% on increasing span length of pavement.

The pavement's free vibration is the sole subject of the current investigation. This study limits for the preliminary design phase of rigid pavements, where a complete three-dimensional finite element analysis is unnecessary. The current approach can be extended to future research using a different method, such as finite element grilling technique, mesh-free technique on reinforced concrete pavements or jointed concrete pavements.

The finite element approach adopted in this paper involves six degrees of freedom for each node. Furthermore, to the best of the authors’ knowledge, no prior study has done seven separate parametric investigations on the modal analysis of rigid pavement resting on two-parameter soil.

Designing a sustainable bituminous concrete with long-term performance is a challenging problem. In addition, strength of the subgrade has a crucial impact on pavement design. This paper aims to concentrate on subgrade soil stabilization with granite dust powder (GDP) and crumb rubber powder (CRP) to improve the engineering properties of the soil. Further design of bituminous concrete pavement with cement-treated layers in base and subbase course layers was carried out with life cycle cost analysis and life cycle assessment for 1 km of a four-lane national highway.

Subgrade soil stabilized with GDP and CRP is characterized as per Indian Standards (IS)-2720 to determine the optimum dosage. Further, the mechanistic-empirical pavement design was carried out using Indian Road Congress-37 (2018), analyzed using IITPAVE software and validated with ANSYS software. The life cycle cost analysis is carried out using the net present value method, and the life cycle assessment is performed according to the cradle-to-grave approach.

A soil mix comprising 10% GDP and 2.5% CRP yielded a soaked California bearing ratio value of 6.58%. In addition, the design of bituminous concrete pavement with cement-treated granular layers showed a 26.9% reduction in life cycle cost and 59.4% reduction in total carbon footprint per kilometer compared to the pavement with traditional aggregate layers.

The research on subgrade stabilization with sustainable materials like GDP and CRP incorporating mechanistic empirical pavement design, life cycle cost analysis and life cycle assessment is limited. Overall, the study recommends the use of GDP and CRP to stabilize soil for subgrade application and incorporate cement-treated granular layers, which offer economic and environmental benefits compared to traditional pavement construction.