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The aim of this paper is to investigate the sediment and pollution profiling and particle size distribution with depth within permeable paving structures, both with and without a geotextile.

Test rigs set up in an earlier pilot study were used for four separate but linked studies. Street dust was applied to rigs C and D to determine the retention of sediments. Heavy metals together with street dust were applied to rig A and B (previously control rigs) to determine the effect of sediment on the pollution removal capabilities of the test rigs. Following the application of sediment, rigs A and B were carefully taken apart to determine pollution profiles and particle size distributions.

The findings reveal that sediment does have an effect on the metal removal capabilities of permeable paving systems, but there was minimal difference between the rigs with a geotextile and without. Pollution profiling within the test rigs identified that the greatest concentration of metals was in the surface sediment and that both rigs removed similar percentages but the concentrations of metals were distributed differently. It was also found that after between 10 and 15 years of sediment application paving rigs began to “block” causing reduced infiltration rates. Unfortunately it is difficult to explain the variations of particle size distributions found with depth in the paving structure. It had been expected to find progressively higher proportions of finer material with depth. However, the reverse was true, with a higher proportion of fines in the sediment applied to the surface and a progressive increase in the proportion of coarse material with depth

The conclusions confirm the effects of sediment within a permeable paving structure and indicate the loading at which the infiltration rates become affected. These results may help to determine a maintenance programme, however this would require further research.

The paper provides a comparative study on pollution and sediment profiling within a permeable paving structure both with and without the inclusion of an upper geotextile. It provides valuable insight into the amount of sediment on paving before it becomes blocked. The methodology and results reported in this research could be used for further studies to provide more evidence as to whether the inclusion of an upper geotextile is beneficial.

The purpose of this paper is to propose a theoretical model to predict the mechanical behaviour of needle punched heavy geotextiles in uniaxial tensile test.

The model was constructed using theory of layered composite materials and finite element method. The properties of a reference fabric were used as initial data in theoretical calculations and a commercially available finite element program was chosen to carry out stress analysis. A comparison is made between theoretical calculations and experimental data to evaluate the deformation mechanism of geotextile fabrics in uniaxial tensile test.

The results indicate that compatible data were predicted in terms of stress values and stress distribution of fabrics. The inconstant lateral contraction of nonwoven fabrics in tensile test is also successfully simulated by the model. However, in the case of elongations, the model could not predict the strains of heavy geotextiles accurately.

The study aims at predicting the mechanical behaviour of needle punched heavy geotextiles by using the structural and mechanical properties of a “reference fabric” instead of constituent fiber properties.

The use of geotextile sand containers (GSCs) in shoreline protection systems has moderately grown since the first applications in the 1970s and increasingly used as an alternative to natural stone, slag, and concrete. Due to their economical, technical and ecological advantages, the use of geotextiles and geocomposites for filter and drainage functions is increasing worldwide and has a 40 year history already. For coastal protection measures, nonwovens are proven to have long-term resistance against ultraviolet radiation and saltwater. High elongation behavior provides superior properties during loading in coastal protection means, which is determined as being the biggest risk for damaging geotextiles. Such applications require certain functional characteristics in the geotextiles, besides their basic properties, which are required to be engineered by the judicious optimization of the needlepunching process. In this study, the effect of the process parameters including punch density and depth of needle penetration has been investigated on the mechanical (tensile strengths in the machine and cross-machine directions) properties of needlepunched nonwoven geotextiles. These process parameters are then empirically related to the fabric properties by using a multiple regression technique.

Constrain on availability of waste landfill sites and stinging environmental regulations are the major reasons stimulating interest in the use of Limited Life Materials in construction industry. The concept of limited life geotextiles seeks to emphasize a clear definable working life, where materials are designed so that progressive loss of their capability with time is matched with the improvement in the ground conditions with time. By clearly defining a working life of the geotextile base on the improvements in ground conditions overtime will reduce over-designing and construction. This paper mainly focus on the ability of biodegradable geotextiles to provide reinforcement to embankments constructed on soft ground where the foundation soil is too weak to support the embankment on it. It is well known that any degradable (decay) material has negative exponential function. Consequently nonlinear function which approximates decay phenomenon is engrossed with errors. The existing methods of investigating time dependent behaviors of Basal reinforced embankment on the soft soil are based on discrete functional equations derived from large number of data. This paper provides an update of effective mathematical equation for predicting limited life span of geotextiles derived from the fundamental mathematical and engineering principles which governed biodegradable materials and soil parameters.

The stone dust column was used to strengthen the sample and had a significant effect on improving the shear strength of the kaolin clay. The application of stone columns, which can improve the overall carrying capacity of soft clay as well as lessen the settlement of buildings built on it, is among the most widespread ground improvement techniques throughout the globe. The performance of foundation beds is enhanced by their stiffness values and higher strength, which could withstand more of the load applied. Stone dust is a wonderful source containing micronutrients for soil, particularly those derived from basalt, volcanic rock, granite and other related rocks. The aim of this paper is to evaluate the properties of soft clay reinforced with encapsulated stone dust columns to remediate problematic soil and obtain a more affordable and environmentally friendly way than using other materials.

In this study, the treated kaolin sample's shear strength was measured using the unconfined compression test (UCT). 28 batches of soil samples total, 12 batches of single stone dust columns measuring 10 mm in diameter and 12 batches of single stone dust columns measuring 16 mm in diameter. Four batches of control samples are also included. At heights of 60 mm, 80 mm and 100 mm, respectively, various stone dust column diameters were assessed. The real soil sample has a diameter of 50 mm and a height of 100 mm.

Test results show when kaolin is implanted with a single encased stone dust column that has an area replacement ratio of 10.24% and penetration ratios of 0.6, 0.8 and 1.0, the shear strength increase is 51.75%, 74.5% and 49.20%. The equivalent shear strength increases are 48.50%, 68.50% and 43.50% for soft soil treated with a 12.00% area replacement ratio and 0.6, 0.8 and 1.0 penetration ratios.

This study shows a comparison of how sample types affect shear strength. Also, this article provides argumentation behind the variation of soil strength obtained from different test types and gives recommendations for appropriate test methods for soft soil.

Introduction The description ‘riverside property’ is commonly used if any part of the boundary is formed by a waterway, be it a grand sweep of the tidal Thames or a trickling narrow stream.

Knitted fabrics have been widely used in a wide range of applications such as apparel industry. Since these fabrics are continuously subjected to the long-term tensile stresses or tensile creep in real conditions, investigation of viscoelastic behavior of sewn knitted fabrics would be important especially at the seamed area. The paper aims to discuss this issue.

A lockstitch machine was used to produce sewn samples by knitted fabric. Factors such as stitch per inch (SPI), thread tension and thread type were variables of the model. Tensile creep tests under constant load of 200 N were conducted, and creep compliance parameter D(t) of samples was obtained as a response variable. A successive residual method (SRM) was also used to characterize viscoelastic properties of sewn-seamed fabrics.

The instantaneous elastic responses of the seamed samples were less than those of the neat fabric (fabric with no seam). An increase in sewing thread strength increases the instantaneous elastic response of the sample. SPI and thread tension have an optimum value to increase E₀. High tenacity polyester thread, due to its higher elastic modulus, caused a larger E₀ than polyester/cotton thread in sewn knitted fabric. Characteristics of seam including sewing thread type, SPI and sewing tension have significant influence on T₀. Sewn-seamed fabric by high modulus thread shows less viscous strain T₀ than the neat fabric (fabric with no seam). Viscous strain T₀ decreases as SPI changes from 8 to 4 and/or 12. SPI and thread tension have an optimum value to increase the viscous strain T₀. E1 is the same for optimum seamed fabric and fabric sample but T1 is about two times greater for seamed fabric. Retarded time for creep recovery increases by sewing process but characteristics of seam have significant influence on E1 and T1. All sewn knitted fabric samples used in this study could be described by Burger’s model, which is a Maxwell model paralleled with a Kelvin one.

This paper is going to use a different method named successive residuals to model the creep behavior of seamed knitted fabric. On the whole, this paper paved a way to obtain viscoelastic constants of sewn-seamed knitted fabrics based on different sewing parameters such as the modulus of elasticity of the sewing thread, SPI and sewing thread tension.

Geotechnical fills are used for building roadway embankments, filling in behind retaining walls, and as backfill above buried pipelines. Lightweight fill reduces the load so structures can be built more economically. A new lightweight geo‐material made from recycled plastic bottles glued together in their original post‐consumer form was developed. The purpose of this work is to explore the use of this new material as a lightweight geotechnical fill.

Through a preliminary laboratory and field study, aspects of the physical and mechanical characteristics of the recycled plastic bottle blocks were investigated. This new material is currently undergoing field trials behind a retaining wall on a bicycle path.

It was found that the average density of this new material is very low, at 32.63 kg/m³ (2.04 lb/ft³), with 59.5 percent of a block made up of recycled plastic bottles. The plastic bottle waste stream obtained from a recycling plant is gap‐graded having approximately 25 percent of the bottle volume at the 2 l bottle size with the remaining 75 percent at the 500 ml bottle size. Unconfined compression tests on small ten‐bottle samples produced strengths of 60 kN/m² (1,250 lb/ft²).

Testing indicates that this material may be useful as a lightweight geotechnical fill over soft soils or behind retaining walls; as an energy‐absorbing crash barrier for highway, race track, or airport safety; as ground and building insulation for Arctic construction; as floating barriers or platforms for offshore work; or for acoustic or vibration dampening for manufacturing processes.

This work explores the use of large volumes of recycled plastic bottles as an environmentally friendly geotechnical engineering material. Engineering parameters for this new material are presented as well as a discussion of an ongoing field study. The information presented here is the first step in understanding this new material with respect to civil engineering applications.

The purpose of the paper is to present a new method of controlling through susceptible slopes in order to reduce the risk of landslides.

Geotechnical and geological characteristics were collected and different FEM analyses were carried out in a case study of the Alasht valley in Northern Iran in order to determine susceptibility to landslides and consider appropriate countermeasures. Gravel drain piles have a real feel of reducing the pore water pressure in times of seismic loading, so they are used as a remediation method. The results clearly show their effects and an increase in safety as a result.

Since the water table situation has a significant effect on stability, the present study focused on an example of using a seepage controlling system and its effect on the safety factor for different slopes in the area of Alasht, Northern Iran. Several FEM analyses were carried out on a landslide susceptible case. The results from FEM analysis of different slopes in the study area show a high susceptibility to landslides for six sites. Installing a gravel drain pile surrounded by a non‐woven geotextile layer leads to an increase in the safety factor against landslides. As a result, after installing gravel drain piles in the upper parts of slopes in order to control run out and ground water rising up in times of heavy rainfall, the safety factor against landslides in both static and seismic loading improved significantly.

The literature regarding controlling seepage in order to reduce the risk of landslides is limited. This paper collects and analyses geotechnical and geological data from the Alasht valley as an example to show the high risk of susceptibility to landslides.

Recently, there has been increased interest in the use of simulation for real‐time planning, scheduling, control of construction projects and obtaining optimum productivity. The purpose of this case study is to demonstrate the use of simulation as an effective tool for estimating production rates in an attempt to prepare optimal time schedules.

Gaza Beach‐Camp Shore Protection Project was taken as a case study. The case study is used to demonstrate how to estimate effectively the production rates of labour and equipment during the implementation of the project activities and to estimate the duration of the project using process simulation. The model simulates the construction of 1,600 m of gabions divided into 32 identical stations. Probabilistic distribution functions were used to fit the time functions for each process and sub‐process based on 100 replications.

The simulation output generated three probabilistic values for completing each activity upon which the overall project completion time is determined. The resources utilizations for all processes were also generated and used in the determination of the average production rates.

The computation of productivity based on effective resources utilization has been demonstrated to give better results than estimating productivity based on aggregate resources assignments.