JournalTOCs

Transportation Infrastructure Geotechnology
Journal Prestige (SJR): 0.592

Citation Impact (citeScore): 1
Number of Followers: 8

Hybrid journal (It can contain Open Access articles)
ISSN (Print) 2196-7202 - ISSN (Online) 2196-7210
Published by Springer-Verlag

[2626 journals]

Performance of Multi-Helix Pile Embedded in Organic Soil Under Pull-out
Load
- Abstract: Abstract The performance of multi-helix plate piles under pull-out load in organic soils is tested through an experimental investigation on helical piles. On the basis of experimental tests, this study presents the feasibility of multi-helix pile behavior installed in organic soil. Tests were carried out on two different densities of organic soil. The helix piles were made of 16-mm-diameter mild steel shafts to which mild steel plates of 50 mm for both diameter and pitch were welded. Tests were performed on single-, double-, triple-, and quadruple-helix cylindrical screw piles with helix spacing to diameter ratios varying from 0.1 to 0.5. A set of tests was also performed to evaluate efficiency. The results of the tests are used to illustrate the difference in ultimate capacity for the different geometry anchors. The results showed that the helical pile behavior depends essentially on pile geometric characteristics and soil density. According to the achievements, pull-out load capacity of helical piles depends on spacing ratio (S/D) and number of plates.
  PubDate: 2019-03-01
Evaluating the Applicability of Geocell-Reinforced Dredged Sand Using
Plate and Wheel Load Testing
- Abstract: Abstract Mismanagement of large amounts of sediment from dredged harbors has resulted in major environmental and economic problems in some coastal areas. The beneficial use of dredged material can reduce the volume of these materials, but their insufficient strength for engineering applications makes them more appropriate for use in soil improvement. The geocell-reinforcement technique can be implemented to increase the strength and stiffness of weak soil. This paper investigates reuse of dredged sand as backfill in a road embankment by employing the full-scale wheel and plate loading technique. In order to achieve a suitable layered system, which satisfies deflection criteria and rutting limitations, the backfill was reinforced with geocells having different cover layers (well-graded gravel and dredged sand). The results revealed that the load-bearing capacity can be doubled with the use of geocell reinforcement accompanied by well-graded gravel as the cover layer. In this regard, the wheel rut depth was reduced to one third of that of the unreinforced backfill.
  PubDate: 2019-03-01
Permanent Deformation Prediction Model of Unbound Granular Materials for
Flexible Pavement Design
- Abstract: Abstract Constitutive prediction models in flexible pavement are used to predict the permanent deformation (PD) of the unbound granular materials (UGMs). The most recent flexible pavement structural design guide in Australia does not consider the response of the UGMs layers as a design criterion. Additionally, it referred to the absence of an appropriate prediction model. The available prediction models have complex equations with many variables; the use of some of which has been found to be unsuitable in Australia. Thus, the aim of this study was to develop a new simple constitutive model based on an empirical regression equation, which has two predictor variables and four regression parameters. Repeated load triaxial test data covering many loading cycles and stages of stresses were used in order to validate the proposed model by calibration. The tested materials, specified by VicRoads as high-quality base and subbase crushed rocks, were used to prepare 46 samples with a range of moisture contents, gradations, densities, and stress conditions. Additional validation was conducted by predicting the PD response of recycled crushed concrete for different stress conditions. The proposed model excellently matches the experimental PDs with the sum of squared error less than 0.060 and R2 more than 0.96 over the tested matrix for both the crushed rocks and recycled concrete. This high prediction accuracy could lead to a better design of pavement materials and their thicknesses. A new update is proposed for the current Austroads flexible pavements design procedure by involving two more critical locations as performance criteria in the base and subbase layers based on the developed constitutive model. Adopting the proposed model can better generalise the design procedure to determine the accumulated vertical PD for the whole layer system.
  PubDate: 2019-03-01
Probabilistic Approach for Development of Track Geometry Defects as a
Function of Ground Penetrating Radar Measurements
- Abstract: Abstract Recent research has shown a relationship between track geometry defects and track subsurface conditions as measured by Ground Penetrating Radar (GPR). This paper presents the results of a comprehensive study looking at the development of a probabilitic model for the prediction of track geometry defects as a function of key subgrade parameters as measured by GPR. Specifically, several Logistical Regression (LR) analyses were performed, to include conventional LR modeling as well as a hybrid LR modeling approach based on Hierarchical Clustering Analysis with Histogram Data. The result was a higher order polynomial Logistic Regression model for determination of the probability of a track geometry surface defect occurring at locations with measured ballast fouling and measured ballast thickness. The results showed that there was a statistically significant relationship between high rates of geometry degradation and poor subsurface condition as defined by the GPR parameters: Ballast Fouling Index (BFI) and Ballast Layer Thickness (BLT). Furthermore, a predictive model was developed to determine the probability of a high rate of geometry degradation as a function of these key GPR parameters.
  PubDate: 2019-03-01
The Effect of Cyclic Load Characteristics on Unbound Granular Materials
- Abstract: Abstract Vertical load characteristics used in laboratory repeated load triaxial tests (RLTT) have a significant impact on evaluating unbound granular materials (UGMs) for the flexible road pavements. Many studies and standard testing protocols suggest a diverse range of these characteristics (i.e. stress magnitude, pulse shape type, loading period and rest period). Several studies have been conducted to identify the factors that affect the permanent deformation (PD) and resilient modulus (Mr) of UGMs. However, the effect of the pulse shape types has not yet been investigated. The aim of this study is to experimentally investigate the effect of vertical stress pulse shape type on the PD and Mr behaviour of the UGMs using RLTT. For further assessment, a parametric analysis was also conducted using eight existing PD and Mr constitutive models. Three typical vertical stress pulse shape types were investigated, namely trapezoidal, haversine and triangular, as suggested by several international testing protocols. The results show that tested UGMs, using trapezoidal stress pulse, produced higher PD and lower Mr than haversine and triangular pulses under controlled experimental conditions. As the loading span of the pulse increased, the amount of PD also increased, and Mr decreased. Some of the regression parameters of the investigated constitutive models for both PD and Mr showed correlations with the type of applied stress pulses. Moreover, it was found that the PD and Mr models were material dependent, as a better statistical fit was achieved for the granite than the basalt samples. It is recommended to take extra precautions while adopting a particular type of vertical stress pulse shape as the results may vary widely.
  PubDate: 2019-02-08
Laboratory Evaluation of Inter-layer Bond Strength Between Bituminous
Paving Layers
- Abstract: Abstract Tack coats are normally applied prior to overlaying to provide adequate adhesion or bonding between two bituminous layers. This is a study in the attempt stage to evaluate the inter-layer bond strength between two common types of bituminous paving layer combinations such as (i) bituminous concrete over dense bituminous macadam (DBM-BC) and (ii) semi-dense bituminous concrete over bituminous macadam (BM-SDBC) samples in the laboratory. The specimens representing the said combinations have been prepared in the laboratory using normal Marshall procedure with minor exceptions. The different types of tack coat materials, namely rapid setting (RS) bitumen emulsion and medium setting (MS) bitumen emulsion, VG 10 bitumen and VG 30 bitumen have been used at different application rates for providing the inter-layer bond between the bituminous layers. The samples thus prepared have then been tested at four different test temperatures on a specially fabricated attachment (named inter-layer bond strength tester device) fitted to the loading frame of the Marshall testing apparatus. It is observed that the inter-layer bond strength (ILBS) depends on the test temperature, type of tack coat material, and application rate of a respective tack coat. Out of four tack coat materials considered in this study, MS offers maximum ILBS with minimum quantity requirement in both DBM-BC and BM-SDBC layer combinations.
  PubDate: 2018-12-01
Failure Mechanisms of Shallow Tunnel in Sandy Ground
- Abstract: Abstract The deformations and failure mechanisms of the tunnel face in a shallow ground were studied using a geotechnical centrifuge. The test setup comprised of a half section of tunnel of diameter (D) of 10 cm with a movable rigid face plate, both created using 3D printing technique. The plate was attached to a displacement-control actuator which moved into the tunnel to generate ground failure. In the testings, the ground of Nevada sand was prepared in a rigid test box to render different shallow burial depths C simulating C/D ratios of 0.3, 0.5, and 0.7. Dry, moist (5% water content), and saturated conditions were considered. The transparent wall of the test box allowed direct visualization and recording of deformations, and subsequent image analysis. The C/D ratios and water contents affected the vertical stress distribution in the ground. The observed failure surfaces were comparable with the mechanisms proposed by Horn.
  PubDate: 2018-12-01
Limit Equilibrium Stability Analysis of Layered Slopes: a Generalized
Approach
- Abstract: Abstract Traditionally, application of the conventional logarithmic spiral in limit equilibrium (LE) analyses has been limited to homogenous materials. Herein, a modification of the conventional logarithmic spiral LE approach is proposed to account for transitions in soil conditions and provide insight into the internal statics associated with this approach, termed the compound log-spiral (CLS). Comparing both factor of safety (FS) and failure surfaces for a range of frictional strength combinations, the CLS approach demonstrates good agreement with results derived from both generalized, commercially available rigorous LE analyses and finite element analyses. The utility of the CLS method is further demonstrated through an example where the stability of a heavily stratified seacliff is considered. The proposed method satisfies equilibrium at a limit state without resorting to internal statistical assumptions associated with traditional LE approaches. Furthermore, it enables the explicit determination of internal statics, such as inter-slice shear forces, inter-slice normal forces, inter-slice angle, line of thrust, and normal stress distributions, which is a less-than-trivial task for the complex slip surface geometry realized in heterogeneous slope failures. Subsequently, the reasonableness of results could be assessed.
  PubDate: 2018-12-01
Geotechnical Investigations for Evaluating the Performance of the
Misaligned MSE Wall: a Case Study
- Abstract: Abstract This paper presents the details of the geotechnical investigations carried out to evaluate the performance of the misaligned Mechanically Stabilized Earth (MSE) wall in India. The reported MSE wall is part of the approach to the railway over bridge in Hyderabad-Bangalore highway. The MSE wall of height 13.85 m was misaligned vertically after the highway was opened to traffic in 2010. Initially, the only option seemed was to dismantle and reconstruct the MSE wall. However, the detailed geotechnical investigation revealed that the existing wall can be retained with minor repair works. As part of the geotechnical investigations, both field tests and the design analyses were performed. The field tests included standard penetration test, multichannel analyses of surface waves, and ground penetrating radar. The design analysis included the stability assessment of the MSE wall using SLIDE software. The results of the investigations revealed that there was no structural instability in the wall. The major cause of the misalignment was attributed to poor construction practices. As part of the rehabilitation, minor repair works were performed. After the completion of the rehabilitation, the wall has sustained heavy traffic loads in the past 5 years without developing any additional misalignment or cracks.
  PubDate: 2018-12-01
A Generic Design Protocol for Geosynthetic Reinforced Soil Foundation
- Abstract: Abstract This technical note presents a generic step-by-step design protocol based on consideration of bearing capacity of reinforced soil foundation (RSF) on a level ground. The technical note begins with a synopsis of notable studies on bearing capacity of geosynthetic reinforced soil (GRS) and a brief description of an analytical model for load-carrying capacity of closely-spaced soil-geosynthetic composites. The generic RSF design protocol was developed based on findings of the notable studies and the analytical model. Specifically, the design protocol determines (i) reinforcement configuration of RSF (including reinforcement depths, spacing, and width), (ii) required reinforcement stiffness and strength for selection of reinforcement in RSF, and (iii) the increase in ultimate bearing capacity of RSF if the width of RSF is increased to fulfill design requirements A design example for RSF of a GRS bridge abutment is also given to illustrate how the design protocol can be applied.
  PubDate: 2018-12-01
A Finite Element Investigation on Displacements of Reinforced Soil Walls
Under the Effect of Typical Traffic Loads
- Abstract: Abstract The present work examines the effect of a uniformly distributed traffic load that is located on top of a reinforced soil wall, in terms of displacements of the external face of the wall. Reinforced soil walls of three different heights (3, 6, and 12 m) are analyzed using an appropriate finite element program. Analyses are performed under static loading for plane strain conditions. Based on the results, regardless of the height of the wall, when the traffic load is located outside the reinforced soil mass, its effect on the vertical displacements of the wall’s face are negligible. In terms of relative horizontal displacements (ratio of displacements over wall’s height), computed values varied between 0.31 and 0.62% for different wall heights and different load locations. In any case, regardless of the height of the wall, when the load starts at a distance of 2 m behind the rear end of the wall, then practically the wall does not sustain any effect in terms of horizontal displacements.
  PubDate: 2018-09-01
Load Transfer of Drilled Shafts: Modeling and Simulating for Probability
Analysis
- Abstract: Abstract Modeling and simulating load transfer data is essential when conducting probabilistic analyses for service limit state design of deep foundations. Before the research presented herein, there are no available records of a functional load transfer model or a quantified uncertainty for drilled shafts in shales (cohesive intermediate geomaterials). In addition, there were no methodologies for incorporating and simulating the variability and uncertainties of a load transfer model for probabilistic analyses. Based on a large data collection from full-scaled load testing on drilled shafts in shales, regression analyses were carried out to find the best fit model that reflects data, as well as their variability and uncertainty. Intensive nonlinear regression analyses were performed using constant standard deviation and constant coefficient of variation assumptions. Five different functional models and two approaches (collective and individual) were utilized. Accordingly, two methods to simulate the load transfer data are proposed for Monte Carlo simulation to incorporate the uncertainty of the models in probabilistic analyses. Recommendations were made to use non-weighted least square regression and collective approach of analysis to analyze the load transfer data. For the first time, quantified variability of the load transfer data, as well as the method to simulate the load transfer data, is available for probabilistic analysis for service limit state of drilled shafts in shales.
  PubDate: 2018-09-01
Strength Behaviour of Clayey Soil Mixed with Pond Ash, Cement and Randomly
Distributed Fibres
- Abstract: Abstract An experimental program was undertaken to study the effect of inclusion of pond ash and randomly distributed polypropylene fibres on the strength behaviour of cement-stabilized clayey soil. In the present investigation, 19 combinations of fibre-reinforced cement-stabilized clayey soil-pond ash mixes at three different percentages of pond ash (i.e. 10, 20 and 30%) and two different percentages of polypropylene fibres (i.e. 0.5 and 1%) of length 6 and 12 mm with 5% cement content were prepared. The combinations of clayey soil-cement-pond ash-fibres were subjected to a series of standard proctor test, unconfined compressive strength and split tensile strength tests. Based on favourable test results obtained, it can be concluded that partial replacement of cement-stabilized clayey soil by pond ash with the inclusion of polypropylene fibres causes a significant increase in strength, decrease in the stiffness, and rate of loss of post-peak strength. The fibre inclusion changed the brittle behaviour of the composite to ductile. The inclusion of 1% fibres of 6 mm length or 0.5% fibre of 12 mm length has the same impact on the unconfined compressive strength and split tensile strength of the mixtures. The study demonstrates that pond ash can be used successfully as partial replacement of the clayey soil by using reinforcement and cement.
  PubDate: 2018-09-01
Analysis of Stress-Deformation Behavior of Soil-Geosynthetic Composites in
Plane Strain Condition
- Abstract: Abstract A study was undertaken to investigate stress-deformation behavior of soil-geosynthetic composites (SGC) by finite element method of analysis. Five field-scale experiments conducted on representative SGC of different reinforcement stiffness/strength and reinforcement spacing were used to validate the analytical model. An elasto-plastic soil model, referred to as the hardening soil model, was selected to simulate behavior of compacted fill in the SGC experiments. Model parameters were determined from results of large-size triaxial compression tests by following a set of procedure without back-calculation or calibration. Measured external and internal displacements, including vertical strains, horizontal displacement profiles, and internal movement at selected points of all five SGC tests, were found to be in very good agreement with simulation results from the analytical model up to an applied pressure of 1000 to 2000 kPa. The validated model therefore serves as a reliable tool for investigation of stress-deformation behavior of soil-geosynthetic composites. This paper presents validation of the analytical model, analysis of stresses and deformation of SGC, and influence of factors such as reinforcement stiffness, reinforcement spacing, soil stiffness and strength parameters on stress-deformation behavior of SGC. The study helps to gain improved understanding of stress-deformation behavior of soil-geosynthetic composites.
  PubDate: 2018-09-01
Modeling the Time- and Temperature-Dependent Response of Cohesive Soils in
a Generalized Bounding Surface Framework
- Abstract: Abstract The Generalized Bounding Surface Model (GBSM) synthesizes many previous bounding surface models for cohesive soils and improves upon their predictive capabilities. Following an overview of the GBSM and its extension to account for non-isothermal conditions, the predictive capabilities of the model are assessed.
  PubDate: 2018-09-01
The 2018 Burmister Lecture
- Authors: Hoe I. Ling
  PubDate: 2018-04-26
  DOI: 10.1007/s40515-018-0054-1
Effect of Load Eccentricity on the Bearing Capacity of Strip Footings on
Non-homogenous Clay Overlying Bedrock
- Authors: Mohamed Younes Ouahab; Abdelhak Mabrouki; Mekki Mellas; Djamel Benmeddour
  Abstract: Abstract In underwater infrastructure design, foundations are embedded in soft clay seabeds that exhibited non-homogeneity of cohesion, and subjected to combined actions of vertical, inclined or eccentric loads due to the environmental conditions such as self-weight, wind and wave forces acting on substructure. This paper investigates the undrained bearing capacity for surface and embedded strip footings on non-homogenous clay overlying bedrock. Elasto-plastic finite element analyses are carried out for perfectly rough strip footings on Tresca soil under vertical eccentric loads. Meyerhof’s effective width rule is examined for the cases of surface and embedded footings in non-homogeneous clay. The effect of load eccentricity on the distribution of the normal stresses under strip footings is also investigated in this study. It is found that the effective width rule provides a conservative estimate of the bearing capacity. The elasto-plastic calculations predict that tensile stresses occur for surface footings because of the full bonding at the soil-footing interfaces, while for embedded footings, there is no tensile stresses.
  PubDate: 2018-04-21
  DOI: 10.1007/s40515-018-0055-0
Effect of Successive Impact Loading on Compactability, Microstructure, and
Compressibility Behavior of Micaceous Sand
- Authors: P. Seethalakshmi; Ajanta Sachan
  Abstract: Abstract Micaceous soils are generally known for their high compressibility, low compactability, and low shear strength behavior. Mica particles are flaky, flexible, and resilient nature with low stiffness and hardness due to numerous foliated intact mica flakes, which allows them to undergo deformation upon loading and rebound upon unloading. However, the weak mica particles among strong sand particles are highly susceptible to crushing, which affects the performance of geotechnical structures. The current research is focused on the effect of successive impact loading on crushability, compactability, compressibility, and microstructure of micaceous sand containing 30% mica. Significant increase in MDD, fine content, and compression index of micaceous sand was observed with the increase in successive cycles of impact loading. The reduction in resilient nature of micaceous soil due to crushing of intact mica particles along with the reduced bridging and ordering combination of sand-mica particles could be responsible for altered compactability behavior of micaceous sand. The increased percentage of fines due to crushing of mica particles caused the reduction in stiffness leading to higher compressibility of micaceous soil.
  PubDate: 2018-03-07
  DOI: 10.1007/s40515-018-0052-3
A New Analytical Model for Estimating the Natural Frequency of
Pile-Supported Bridges
- Authors: Rasoul Gholami; Vahid Shirgir; Ali Ghanbari; Mohsen Shahrouzi
  Abstract: Abstract The common design for earthquake loading assumes that bridges are fixed at their bases. In reality, interaction between soil and structure decreases the overall stiffness of the structural system. This is not always desirable and may elevate the fundamental period of the system. The current study set to assess soil-structure interaction (SSI) impacts on dynamic performance of pile-supported bridge piers. The bridge foundation is assumed as a distributed mass pile, and a new analytical model is proposed to predict seismic analysis of pile-supported bridges. Applying the dynamic equations of motion for system and using virtual work principles, SSI effects were estimated. Based on the analytical model, a new equation is proposed for calculating the natural frequency of pile-supported bridges. Since the proposed model is very similar to real soil-pile-pier systems, this equation can be used to estimate the fundamental period of the single-pier bridges.
  PubDate: 2018-02-12
  DOI: 10.1007/s40515-018-0049-y
In Situ and Laboratory Testing of Small Diameter PVC Irrigation Pipes for
Investigation of Fatigue Failure
- Authors: Mitsuru Ariyoshi; Yoshikazu Tanaka; Akira Izumi; Toshinori Kawabata
  Abstract: Abstract The responses of small PVC pipes to construction stress, traffic load, and internal pressure were measured in the field. The strain in the pipe top rapidly increased by compaction and it remained after compaction. The deformation of the pipe caused by internal pressure did not only inflate uniformly, but it also deformed to the shape of a true circle. The strain increments caused by a 20.7-ton truck load were 70 μ or less, which was much smaller than those caused by water fluctuations in the field. In addition, a cyclic load test was conducted on a pipe excavated after 11 years in operation. A crack occurred at a deflection ratio of only 1.5% in the cyclic load test, although no crack occurred at a deflection ratio of 50% in the flattening test. These results implied that PVC pipes in the field may break because of fatigue, due more to water fluctuations than to traffic loads.
  PubDate: 2018-01-20
  DOI: 10.1007/s40515-018-0048-z