Experimental study of bearing capacity of strip footing on sand slope reinforced with tire chips

Tire chips and tire chips-soil mixtures can be used as alternative fill material in many civil engineering applications. In this study, the potential benefits of using tire chips as lightweight material to improve the bearing capacity and the settlement behavior of sand slope was investigated experimentally. For this aim, a series of direct shear and model loading tests were conducted. In direct shear tests, the effect of contents of the tire chips on the shear strength parameters of sand was investigated. Different mixing ratios of 0, 5, 10, 15 and 20% by volume were used and the optimum mixing ratio was obtained. Then, laboratory model tests were performed on a model strip footing on sand slope reinforced with randomly distributed tire chips. The loading tests were carried out on sand slope with relative density of 65% and the slope angle of 30°. In the loading tests the percentage of tire chips to sand was taken as same as in direct shear tests. The results indicated that at the same loading level the settlement of strip footing on sand-tire chips mixturewas about 30% less than in the case of pure sand. Addition of tire chips to sand increases BCR (bearing capacity ratio) from 1.17 to 1.88 with respect to tire chips content. The maximum BCR is attained at tire chips content of 10%. © 2014 Techno-Press, Ltd

Experimental study of bearing capacity of strip footing on geogridreinforced sand slope

9th International Conference on Geosynthetics - Geosynthetics: Advanced Solutions for a Challenging World, ICG 2010 --23 May 2010 through 27 May 2010 -- Guaruja --In this study the results of a series of reduced-scale laboratory model tests performed on both unreinforced and geogrid-reinforced sand slopes loaded with a strip footing were presented. The aims of this investigation are to determine the effect of the geogrid reinforcement on the bearing capacity and settlement behavior of the strip footing and to suggest an optimum geometry of geogrid placement to obtain maximum reinforcing effect. In the study, the effect of the slope angle, the relative density of sand, the footing dimension, and the geogrid type on the bearing capacity behavior of the strip footing were also investigated. Test results show that the inclusion of geogrid layer at the appropriate location in the fill slope significantly improves the load settlement behavior and ultimate bearing capacity of the strip footing. The maximum improvement was obtained at depth of the 0.5 times the width of the footing. The results also indicate that the bearing capacity of the footing on geogrid reinforced sand slope depends greatly on the slope angle, footing dimension, the geogrid type, and the relative density of sand

Experimental determination and numerical analysis of vertical stresses under square footings resting on sand [Kuma oturan kare temeller altinda oluşan düşey gerilmelerin deneysel tespiti ve sayisal analizi]

In this study, the vertical stress values occurred under the center line of the uniformly loaded square footings were investigated experimentally and numerically. The results of the study were compared with the results of Boussinesq method. Tests were performed in a square shaped test box and pressure transducer was used to measure the stresses. In the numerical analysis, soil was modeled using finite element method with two dimensional axi-symmetric and three dimensional conditions as linear elastic and non-linear elasto-plastic materials and the effect of these models on the vertical stress values was investigated. Finally, a general agreement was observed between the experimental, numerical and theoretical results for the values obtained for predetermined depths of sand and the obtained results are discussed

Experimental determination and numerical analysis of vertical stresses under square footings resting on sand

In this study, the vertical stress values occurring under the center line of uniformly loaded square footings were investigated experimentally and analytically. The results of the study were compared with the results obtained from the Boussinesq method. Tests were performed in a square shaped test box and a pressure transducer was used to measure the stresses. In the numerical analysis, soil was modeled using the finite element method with two dimensional axi-symmetric and three dimensional conditions as linear elastic and non-linear elasto-plastic materials and the effect of these models on the vertical stress values was investigated. Finally, a general agreement was observed between the experimental, numerical and theoretical results for the values obtained for predetermined depths of sand and the obtained results are discussed

An equation for predicting shear strength envelope with respect to matric suction

Determining the shear strength parameters of unsaturated soils generally involves costly, time-consuming and sophisticated testing programme. This paper proposes a new method for prediction of shear strength with respect to matric suction. The variation of shear strength with respect to matric suction is described by using the air-entry value and the internal friction angle of a soil specimen. The validity of the method is tested for a number of suction strength data available in the literature. The shear strengths with respect to matric suction obtained from the proposed method are in nicely good agreement with experimental results. © 2004 Elsevier Ltd. All rights reserved

Nonunion of the tibia following intramedullary nailing treated by Ilizarov external fixator: A case report

Nonunion may be encountered, though occasionally, following fixation of long bone (such as tibia) fractures with an intramedullary nail. Despite availability of several treatment options in such situations, none seems to be ideal. In this study, we reported a case with aseptic tibia nonunion which was treated with Ilizarov external fixator over the intramedullary nail, which is a relatively novel modality with few studies available, and we proposed the method as an effective one with emphasis on further studies to explore the method. © 2013 OMU

Experimental investigation of strip footing on reinforced sand slope [Donatili kum şeve oturan şerit temelin deneysel olarak i·ncelenmesi]

In this study, the ultimate bearing capacity of shallow foundation on geogrid-reinforced sandy slope was investigated using a small scale laboratory tests. Strip footing was used in the model tests. The parameters investigated include the location of the first layer of reinforcement, the number of reinforcement layer and the vertical spacing of reinforcement layer. Some practical design parameters were suggested for the relevant foundation engineering applications. The results of the study were compared with the existing methods and a general agreement was observed. Finally, it was concluded that the ultimate bearing capacity values of strip footing on sloping ground can, depending on the reinforcement geogrid arrangement, be increased up to six times that of the unreinforced case