Geotechnical engineers face several challenges when designing structures over soft soils. These include potential bearing failure, intolerable settlement, large lateral pressures and movement, global or local instability. Geosynthetic-reinforced pile-supported earth platforms provide an economic effective solution for embankments, retaining walls, storage tanks, etc. constructed on soils; especially rapid construction and/or strict deformation of the structure are required. The inclusion...

Field observations and numerical studies demonstrated that stone columns could accelerate the rate of consolidation soft clays. A simplified method for computing is presented in this paper by assuming columns; (1) are free draining; (2) have higher drained elastic modulus than clay; (3) deformed 1D. The formats final solutions vertical radial flows similar to those Terzaghi 1D solution Barron drain wells fine-grained soils, respectively. Modified coefficients introduced account effects...

A theoretically based design method for the thickness of base course unpaved roads is developed in this paper, which considers distribution stress, strength material, interlock between geosynthetic and stiffness addition to conditions considered earlier methods: traffic volume, wheel loads, tire pressure, subgrade strength, rut depth, influence presence a reinforcing (geotextile or geogrid) on failure mode road area. In method, required reinforced calculated using unique equation, whereas...

A theoretically based base course thickness design method for unpaved roads was developed in the companion paper. This paper presents a calibration of using data from field wheel load tests and laboratory cyclic plate loading on unreinforced reinforced courses. The constants are determined during calibration. calibrated is used analyzing test through three case studies. In addition, procedures example provided this to demonstrate use method.

The geosynthetic-reinforced pile-supported embankment is one of the favorable ground improvement techniques used in construction earth structures over a compressible soil when limited time available and deformation permissible. Various methods are for design platform based on various load transfer mechanisms from to piles soil. existence geosynthetic layer makes more complex. This study focuses behavior geogrid-reinforced embankments compared with unreinforced embankments. numerical...

This paper presents a field study of installation effects deep mixed columns on properties the sensitive Ariake marine clay. Cone penetration tests were performed in to evaluate change strength surrounding clay with time. Soil samples taken before and after column variations physical, mechanical, chemical Test results indicated that water content decreased while concentration cations increased as sampling locations approached columns. Shear during but recovered short period curing. continued...

Pile-supported embankments are increasingly being used for highways, railways, storage tanks, etc. over soft soil because of their effectiveness in accelerating construction and minimizing deformation. The stress transfer mechanisms among all the components a piled embankment, including embankment fill, piles (or) caps, foundation soils, complicated. In this study, closed-form solution one-dimensional loading was obtained taking into consideration arching negative skin friction along pile...

Soil arching is a phenomenon describing stress redistribution due to relative movement between adjoining portions. It commonly exists when soil interacts with structure elements, such as tunnels, retaining walls, buried structures, and piles in pile-supported embankments. A yielding or ultimate state of (i.e., the shear equal its strength) mostly assumed analytical models for arching. In reality, level shape slip surface depend on magnitude soil. this study, custom-made trapdoor test box was...

Soil arching is one of the most important mechanisms in piled embankments. To investigate development soil embankments, 14 unreinforced and 8 geosynthetic-reinforced model tests were carried out using a two-dimensional (2D) multitrapdoor test setup with analogical soil. This study revealed that basal geosynthetic reinforcement changed three deformation patterns into two concentric elliptical arches under same conditions. The stress reduction ratios (defined as ratio average pressure on...

This case study presents an investigation on building settlement induced by dewatering for a deep excavation constructed in deposit Tianjin, China. The site is located the Tianjin urban center, around which there are many existing buildings. Geological conditions at involve multiaquifer system with one phreatic aquifer over three confined aquifers. To maintain stability of bottom excavation, cutoff wall was used to block groundwater seepage large diameter wells lower level. Field...

Recycled asphalt pavement (RAP) has been increasingly used as an energy efficient and environmentally friendly paving material is currently the most reused recycled in United States. RAP new hot mix (HMA) mixtures base courses for construction. When a course material, presence of may cause excessive deformation under traffic loading. Geocell, three-dimensional (3D) polymeric geosynthetic cells, was proposed this study to minimize by confining material. Full-scale accelerated tests were...

Geogrid (uniaxial or biaxial) is one type of geosynthetics that has been successfully used in slopes, walls, roads, and other applications. The main application biaxial geogrid to stabilize soft subgrade reinforce weak base courses by providing lateral confinement. confinement due the interaction between aggregates ribs depends on geometry properties geogrid, such as rib shape apertures size, stiffness ribs, aggregates. Research shown cannot provide uniform tensile resistance all directions....

Geosynthetic encasement of individual stone columns can provide additional confinement to the thus increasing their load capacities and reducing lateral vertical deformations. Most past studies have been focused on settlements (i.e. deformations) encased columns. However, transfer mechanism bulging deformation pattern are not thoroughly understood. In present study, four series laboratory model tests in a large-scale testing tank were performed investigate effect geogrid deformations...

Geosynthetic-reinforced pile-supported embankments have been increasingly used worldwide to support earth structures. A significant amount of research has conducted by many researchers and engineers in recent years. This paper provides a state-of-the-art review this technology, important developments results obtained throughout the years that help better understand mechanisms play an role design, construction, performance these systems. begins with terminologies historical developments. It...

Soil arching exists in many geotechnical applications, including tunnels, buried pipes, and geosynthetic-reinforced pile-supported (GRPS) embankments. has been mostly investigated using trapdoor tests under soil self-weight and/or uniform surcharge. In real localized surface loading, such as traffic may be applied onto affect or degrade arching. Geosynthetic reinforcement is used GRPS embankments over pipes have effects on mobilization degradation loading. The of loading geosynthetic not yet...

Conventional construction materials used in foundations can encounter serious durability problems contaminated subsurface or marine environments. Fiber-reinforced polymer (FRP) composites are potentially suitable for these harsh environments due to their chemical and corrosion resistant properties. Quantification of the interface behavior between FRP soils is a necessary precursor adoption new geotechnical engineering practice. This paper describes results an experimental study that was...

Theoretical and experimental studies have proven that stone columns can be used for accelerating the consolidation rate of soft soil by providing a drainage path reducing stresses in soil. In constructing fine‐grained soils, however, zones at interface between their surrounding become smeared particles also mixed into aggregates columns. The smear well resistance due to contaminated with reduce effectiveness dissipating excess pore water pressures. A theoretical solution is developed this...

Current design of mechanically stabilized earth (MSE) walls shows that the tensile stress in reinforcement increases rapidly with height. To take advantage both aesthetics and economics MSE while considering high heights, multitiered are often used. In such walls, an offset between adjacent tiers is If large enough, lower reduced. However, a rational methodology for accurately predicts wall performance lacking. AASHTO 98 guidelines limited to two-tiered zero batter. fact, this purely...