One concern usually expressed about the implementation of Intelligent Compaction (IC), especially in tandem with modulus-based spot tests, is the uncertainty in the depth of influence of different devices. The depth of influence is mainly contingent upon the weight, dimensions, and operating settings of the employed roller as well as the characteristics of the underlying materials. This study attempts

Given the substantially increased demand for increased axle loads of heavy haul trains, there is an imperative need to develop sustainable track infrastructure. When subjected to heavy axle loading, ballast aggregates rapidly break down, compromising the particle friction and associated load bearing capacity. Therefore, understanding the deformation and degradation (breakage) of ballast subjected to

Plastic deformation of granular layers in railway tracks under cyclic loading is a key factor controlling the substructure’s stability. In particular, the granular subballast capping layer placed between the ballast and subgrade can undergo permanent deformations due to the moving wheel load of trains. This study was conducted to evaluate the cyclic behavior of recovered plastic (RP) blended at different

This paper presents a scalar- and vector-valued vulnerability analysis of shallow circular tunnel in soft soil. Numerous dynamic analyses were firstly performed to capture seismic response of the tunnel lining under transversal seismic shaking. Subsequently, a series of 15 intensity measures (IMs) are selected and tested to find the optimal IM used in the scalar-valued vulnerability analysis. The selected

The soil stabilisation is employed to construct geostructures as embankments, river levees, road subbases or to backfill excavations, improving the mechanical behaviour and reducing the consumption of extracted primary aggregates. This study is focused on the use of lime/cement treated soils to backfill trenches where high power line cables are buried. Indeed, under these circumstances not only the

The essential task of the ground reinforcement techniques is to keep the rock as stable as possible. In particular passive rock bolt should resist the rock movements along its entire length and through the resulting reaction forces, to improve the load-bearing capacity of the rock. Among different calculation techniques, the calculations based on Block Reinforcement Procedure (BRP) was used in this

With the thermal disturbance caused by engineering construction and global warming, thaw consolidation has become a primary source of subgrade deformation in permafrost regions. Based on the large-strain consolidation theory described by the updated Lagrangian, we study the thermal stability and the thaw consolidation in an ordinary subgrade at the warm and ice-rich permafrost (WIRP) site of the Beiluhe

Most chemical stabilization guidelines for subgrade/base use unconfined compressive strength (UCS) of treated soils as the primary acceptance criteria for selecting optimum stabilizer in laboratory testing. Establishing optimal additive content to augment UCS involves a resource-intensive trial-and-error procedure. Also, samples collected from discrete locations for laboratory trials may not be representative

Climate change and human action significantly impact the state of soil, particularly saline and loess soils in China's arid and semi-arid regions. Infrastructure is continuously built on these problematic soil areas, making it crucial to study the impact of external factors on the engineering properties of subgrade soil. This paper proposes a test device by which a few physical conditions (salt content

Accurate measurement of particle shape is necessary to properly investigate the cyclic shear behavior of a soil–geogrid interface. In this study, the particle shapes of crushed limestone, quartz sand, round gravel and spherical granular media were described and quantified in terms of particle regularity. Cyclic direct shear tests were then performed with particles of various shapes for different relative

This paper deals with the determination of upper and lower bounds for the three-dimensional undrained stability of shallow tunnels. The tunnel is circular and a distance between its face and its lining is considered. The soil shear strength is modeled using the Tresca criterion. Results of the upper and lower bounds of the stability number are presented, for several geometrical and resistance configurations

In practice, footings may be constructed near each other which results in an interaction between foundations and leads to significant effect on bearing capacity (BC), failure mechanism, footing settlement and tilting. This paper reviews comprehensively the progress and state-of-the-art relevant to footing interference investigations and applications. This review covers experimental and theoretical

This paper presents a numerical approach to study the damage evolution of secondary tunnel lining under the combined actions of corrosion of the preliminary support and the creep deformation of the surrounding rock. This improved numerical approach contains three main models for: (1) tensile failure of corroding rock bolt; (2) yielding of corroding supporting steel arch; and (3) elastoplastic damage

Gantry-crane pavements and foundations are significant assets within intermodal facilities. The performance of these pavements, which are subjected to highly-variable loads, is critical to safe operations. Traffic interruptions and costs associated with maintaining and rehabilitating distressed or failed pavements in associated areas are of particular importance. The purpose of this study was to evaluate

The use of domestic, industrial and construction waste has been gaining considerable space in recent decades in view of the social and environmental concern in preserving and reusing natural resources. Thus, this article has the premise of studying the use of the mixture of three residues, evaluating the feasibility of using these as a pavement layer. The first residue is the reclaimed asphalt pavement

Although satisfactory treatment effect was achieved from a recent foundation reinforcement practice, where a foundation composed of collapsible loess was treated with the vibratory probe compaction method in northwest China, the mechanisms of the reinforcement was unclear. To reveal the reinforcement mechanism, a series of experimental tests, including scanning electron microscopy, mercury intrusion

The uniaxial compressive strength (UCS) is a vital rock geomechanical parameter widely used in rock engineering projects such as tunnels, dams, and rock slope stability. Since the acquisition of high-quality core samples is not always possible, researchers often indirectly estimate these parameters. The main objective of the present study is to evaluate the performance of the long short term memory

The moisture induced damage is considered a serious threat to the durability of the high-speed railway system. In this paper, an innovative application of thermoplastic polyurethane/waste rubber powder blend (TPU/WRP) with higher elastic modulus was introduced to enhance the water resistance of high-speed railway structure as a waterproof seal layer. The thermoplastic polyurethane has been proved to

Recent laboratory investigations conducted on soils prone to mud pumping have shown that the subgrade soil experiences softening associated with an internal redistribution of moisture when the cyclic stress ratio (CSR) exceeds a certain critical level. This article aims to evaluate the stiffness degradation of these problematic subgrade soils subjected to a wide range of loading conditions. The test

The benefits of increased axle loading in the railway industry are well-appreciated to such an extent that increased axle loading has become a themed topic of interest across all disciplines of railway engineering. However, it remains important to understand the engineering behavior and performance of each track component under increased axle loading. This study was particularly interested in the behavior

Despite the variety of available stabilization methods for the expansive soil, a rapid stabilization and remediation solution for this class of the problematic soil is still needed. Among the available treatment methods, traditional chemical additives such as lime, and cement exhibit satisfying performance over their counterparts. Nevertheless, significant concerns are associated with those chemicals

Machine learning (ML) is becoming an appealing tool in various fields of civil engineering, such as tunneling. A very important issue in tunneling is to know the geological condition of the tunnel route before the construction. Various geological and geotechnical parameters can be considered according to data availability to define tunnels' ground conditions. The Rock Quality Designation (RQD) is one

Pile-supported embankment is popularly used for constructing high-speed railways on soft soils. With train running at high speed, the dynamic load on the pile top generated by the train passages increases noticeably. To keep the long-term settlement of the railway track within a reasonable range, it is necessary to investigate the settlement of piles in soils simultaneously subject to the monotonic

The paper presents an experimental study of the hydromechanical behavior of a compacted clay used in the design of the core of the Boughrara dam (western Algeria). The influence of compaction energy level (CEL) is explored using three different energies: Standard Proctor energy (SP), reduced Proctor energy (SP-20 blows) and enhanced Proctor energy (SP+ 20 blows). The resulting compaction curves are

Soil compaction is a considerable construction activity to ensure safety and durability, notably in the transportation industry. Compaction delay (CD) occurs because of unpredictable cases which may be related to the climatic, environmental, and logistics reasons. Since the time delay in compaction process affects the engineering properties of the materials in road construction, the current study evaluates

Most of the traditional design methods assumed shield tunnel lining as a perfectly formed ring, without special attention to the effect of pre-deformations and inaccuracies produced in the assembling process before the segmental ring is closed. However, these factors can significantly affect the mechanical performance and durability of the tunnel. To make up for the deficiencies of conventional design

Resilient modulus is one of the important parameters used in the analysis and modelling of subgrade behaviour and it is directly related to the safety, economic and lifetime of roads structures. The determination of Resilient Modulus (MR) using repeated load triaxial (RLT) test is expensive, cumbersome and time consuming. Therefore, a new research approach has been adopted in this study based on performing

This paper proposes a three-dimensional fully-coupled numerical model intended for the simulation of the dynamic behavior of ballasted railway tracks under real excitation. It is employed to reproduce the response of a French site located at the high-speed line connecting the two regions Bretagne and Pays de la Loire. The equation of motion is solved in the time domain by means of the finite difference

This work addresses the characterization of physical, chemical and mechanical properties of steel slag in the employment as an aggregate before and after controlled leaching test in Soxhlet extractor. The material was characterized before going through the stabilization process (virgin slag) and after controlled leaching in different periods of 24, 56, 96, 120 h. The steel slag was subjected in the

Enzyme induced carbonate precipitation (EICP) is an innovative ground improvement technique which can enhance soil properties including soil strength, stiffness and hydraulic conductivity by cementing and filling soil pores. The calcium carbonate precipitation has the potential to influence the water retention ability through altering pore-size distribution and void ratio. This study aims to investigate

The present work aims to study a cement-treated sand through resilient modulus (RM) and fatigue life (Nf) tests. The use of the porosity/cement index (η/Civ) for the assessment of mixtures cyclic response was investigated for the first time. A uniform fine clean sand was cement-treated with varying amounts of Portland cement content (from 1% to 9%) and compacted with different voids ratios (0.64, 0

Rail track geometry irregularities can lead to ride discomfort for passengers and redistribution of wheel loads potentially causing derailments. Current techniques for monitoring track settlements involve the use of discrete sensors or vehicle mounted sensors, which make it difficult to capture either spatial or temporal variations in settlement. Shape Array sensors (SAA) can potentially be used to

The rapid drawdown of the water level adjacent to a railway embankment can reduce its stability, which could compromise the safety of train movements. To investigate the effect drawdown on railway embankments as a function of train speed, a coupled finite element-based model was developed accounting for simultaneous deformations, stresses and seepage. To determine maximum safe train speeds, a comprehensive

Soft Bangkok clay (SC) is recognized as a problematic soil in Thailand. This research investigates the possibility of using polyvinyl alcohol (PVA) and high calcium fly ash (FA) geopolymers to improve the strength of SC in deep soil mixing applications. The liquid alkaline activator (L) was composed of sodium silicate (Na2SiO3) and sodium hydroxide (NaOH). The studied influence factors included FA

Nonwoven-geotextile is used to construct soil-geotextile capillary barrier for minimizing water infiltration. However, the sand-geotextile capillary barrier breakthrough can occur due to the low water retention ability and the high saturated permeability coefficient of sand. To address this, enzyme induced carbonate precipitation (EICP) technology was applied to the overlying sand layer to improve

Water infiltration through pavement structures as a result of flooding and/or extreme rainfalls, can adversely influence the bearing capacity of the pavement and lead to its premature failure. Since the entire pavement system will not be always in saturated state, the post-flood water movement throughout its granular layers should be formulated based on unsaturated flow principles. This study is aimed

One of the most practical ways to reduce the demand for natural aggregates in the construction industry and dispose of the construction and demolition (C&D) wastes in landfills is using recycled concrete aggregate (RCA) for pavement base and subbase applications. Previous researches have mainly concentrated on the engineering behavior of C&D aggregates under ambient temperature. Little research has

To better understand adverse impacts of aging on track maintenance, the hydro-mechanical behavior of unsaturated fresh and aged ballasts was investigated by means of saturated permeability tests, water retention tests, and monotonic loading triaxial compression tests. Firstly, the aged ballast was prepared through the Los Angeles abrasion (LAA) test to reproduce the gradation and particle shape for

Up to now, the effect of strain rate on the adhesive bond shearing resistance of stiff clay, which plays a fundamental role in constitutive modeling of such kind of soils, remains unclear. This paper aims to experimentally investigate the strain rate dependency of the adhesive bond shearing resistance of stiff clay. Both undisturbed and reconstituted overconsolidated samples of Merville stiff clay

Soil reinforcement with fibers is a simple, efficient and low-cost (especially by incorporating waste or recycled fibers) technique for enhancing mechanical characteristics of soft soils. This experimental study investigates the effects of recycled tire polymer fibers (RTPF) and glass fibers (GF) on enhancing the strength/deformation properties of clays. A series of compaction, unconfined compression

The Full Depth Reclamation (FDR) technique has recently become a popular rehabilitation method to reconstruct old flexible pavement. Pulverized existing roadway materials are blended with stabilizing agents such as foamed asphalt and Portland cement to form a stiff base course for the new pavement. In Georgia, Portland cement is commonly used as a stabilizing agent for FDR stabilization. One of the

A total of 77 tests have been carried out on various mixes of copper slag (CS), rice husk ash (RHA), hydrated lime (L), ordinary Portland cement (C) in order to find their compaction and strength characteristics. Modified Proctor compaction (MPC) and unconfined compressive strength (UCS) tests have been performed to investigate the compaction and strength behavior of the various combinations, respectively

The ballastless track has been a widely-used track form in high-speed railway (HSR), however, its application is seriously hampered by the railway heave, which is mainly caused by subgrade swelling. In order to identify the mechanism of HSR subgrade swelling and the rules of swelling-induced railway heave response, long-term longitudinal-continuous deformation monitoring and layered deformation monitoring

Owing to its huge area coverage, explosive Compaction (EC) is as an attractive improvement technique in railway projects. Despite many EC case studies in the literature, few experimental tests are conducted to be used for calibration of numerical models. Thus in this study, a field test is conducted on a railway subgrade and simulated with an advanced numerical model followed by a parametric study

Scarcity of traditional construction materials has motivated researchers to explore alternatives, and besides crushed glass, reclaimed asphalt pavement, and scrap tires, to name a few, plastic waste (unwanted or unusable plastic objects) has also gained attention in recent years. Plastic waste is traditionally re-used or recycled, but it often ends up as trash on curbsides, in landfills, or in our

The mechanism of the soil-structure interaction in buried corrugated metal pipes (CMPs) depends primarily on the relative stiffness of the flexible buried pipe and the surrounding compacted backfill material. Several geometric, mechanical, and material characteristics control this complex composite interaction, including the shape and dimensions of the pipe, its burial depth, the effect of the backfill

Many researchers have conducted laboratory studies for assessing the interaction mechanism of soil and geosynthetics and have shown that the performance of flexible pavement is enhanced by geosynthetic reinforcement through extending their service life or decreasing the base course thickness. However, there is a lack of comprehensive comparisons between different studies. This paper reviews laboratory

The idea of using industrial, agrarian, domestic, construction and demolition wastes as sustainable binders substituting Portland cement in stabilization of soils is considered a modern-day concept. The choice of which residues to be used in each specific earthwork is not a simple one, as it largely depends on the distance between where wastes are generated and where they could be used. Material transportation

Problematic soils cause significant damage and distress in pavements from moisture induced volume and strength changes. Calcium based stabilization are well known to permanently stabilize expansive soils. Traditional calcium-based stabilizers typically include lime and cement for ground improvement of plastic clays to enhance strength. Calcium Sulfoaluminate (CSA) cement can be an effective and sustainable

Full-depth reclamation techniques present numerous advantages for pavement rehabilitation strategies. The recycling process produces a thick layer of stabilized or unstabilized reclaimed materials, which is used as a new base layer of RAP aggregates. The compaction of the unstabilized thick layer is critical for adequate permanent deformation behaviour of the reclaimed layer. In some agencies, the

As a device for efficient heat transfer working without external power supply or control instrumentation, a two-phase closed thermosyphon (TPCT) is an engineering instrument for protecting permafrost under embankments from thawing. The process and mechanism of heat transfer in TPCT embankments were well investigated using experimental and theoretical methods. However, the mechanical performance of

Performance evaluation of the embankment subject to climate change and dynamic train loads is important to the safety of high speed railway (HSR). In this study, based on an elasto-plastic unsaturated soil model, a coupled hydraulic-mechanical-air finite element analysis method is proposed, which integrates the analysis under rainfall condition and the analysis under dynamic load in one numerical simulation

This paper studies the bearing characteristics of different types of cast-in-place piles, with or without grouting, based on a bridge construction in Wuqi-Dingbian Expressway. Manual digging piles (MDPs), rotary drilling piles (RDPs), and impact drilling piles (IDPs) are investigated, and an in-situ static load test is carried out on each type of hole-forming method. The post-grouting results show

This paper presents a field measurement of the train-induced vibration in the northwest Shanghai, where Shanghai Metro Line 11 crosses under Beijing-Shanghai Railway. Ground and tunnel accelerations are measured for the separate and simultaneous passages of the ground and subway trains. Vibration characteristics are subsequently analyzed in the time domain and in the frequency domain. Measurement results

Deicing chemicals, when applied to pavement surfaces, occasionally deposited on the ground beyond the road pavement, thus lead to their accumulation in roadside soils and producing secondary salinisation of the ground water. In order to explore moisture and chemical mass transfer in highway subsoils during the winter period, 9 non-saline soil samples of 1 m length were subject to simultaneously freeze–thaw