• Journal of Industrial Technology
• /
• v.34
• /
• pp.45-52
• /
• 2014

In this paper the settlement characteristic of shallow foundation on sandy soil overlained by rigid ground was investigated by analyzing results of model tests. For model experiments, model tests were performed with sandy soils sampled from the field, changing the relative density of sandy soil and the ratio of thickness of sandy layer(H) to the width of model strip footing(B). As result of tests, settlement of sandy soils increases as the value of H/B increases, whereas it increases with relative density of soil. Bearing capacity decreases as the thickness of the sand layer relative to the footing width increases. In order to analyze the settlement characteristics of sandy ground, the results of model tests were compared with the predicted values using the empirical formulas proposed by Terzaghi, De Beer and Schmertmann. The method by De Beer was found to be in good agreements with test results.

• Earthquakes and Structures
• /
• v.12 no.6
• /
• pp.629-641
• /
• 2017

Foundation plays a significant role in safe and efficient turbo machinery operation. Turbo machineries generate harmonic load on the foundation due to their high speed rotating motion which causes vibration in the machinery, foundation and soil beneath the foundation. The problems caused by vibration get multiplied if the soil is poor. An improperly designed machine foundation increases the vibration and reduces machinery health leading to frequent maintenance. Hence it is very important to study the soil structure interaction and effect of machine vibration on the foundation during turbo machinery operation in the design stage itself. The present work studies the effect of harmonic load due to machine operation along with earthquake loading on the frame foundation for poor soil conditions. Various alternative foundations like rafts, barrette, batter pile and combinations of barrettes with batter pile are analyzed to study the improvements in the vibration patterns. Detailed computational analysis was carried out in SAP 2000 software; the numerical model was analyzed and compared with the shaking table experiment results. The numerical results are found to be closely matching with the experimental data which confirms the accuracy of the numerical model predictions. Both shake table and SAP 2000 results reveal that combination of barrette and batter piles with raft are best suitable for poor soil conditions because it reduces the displacement at top deck, bending moment and horizontal displacement of pile and thereby making the foundation more stable under seismic loading.

• Journal of the Korean Geotechnical Society
• /
• v.24 no.7
• /
• pp.51-60
• /
• 2008

In this paper, the behaviour of shell foundation was studied. In the theoretical program, the general shallow foundation theories and failure mechanism developed by Terzaghi, Mayerhof and others were reviewed and compared. In the numerical study, the 2 and 3 dimensional FEM simulations were carried out using an uncoupled-analysis approach. The results obtained from the model test show that the bearing capacity of shell foundation was about 25% to 30% larger than that of general foundation. Due to the cases of shell angle, the maximum bearing capacity of shell foundation shows when the shell angle of foundation was $60^{\circ}$. In addition, even if the shell foundation has various advantages compared with the general foundations as described above, the practical verifications in full scale size will be necessary to use in the field and will be helpful in the technical development of other special foundations.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.36 no.1
• /
• pp.39-53
• /
• 1994

To investigate the behaviour of the embankment on very soft foundation reinforced geotex- files,the laboratory model test in order to analyze the elementary effects of geotextile reinfor- cement and the finite element program analyzing the stresses and deformations characteristics was carried out. A two-dimensional nonlinear finite element program called GEOTEXT(a modification of ISBILD) for the static analysis of embankment on very soft foundation reinforced geotextiles has been developed. Both linear and nonlinear hyperbolic stress-strain soil models are inclu- ded, and incremental and stage construction can be simulated. However, the program GEO- TEXT is not developed herein as an adaptable design tool for practicing engineer. It was found that the geotextile reinforcement significantly reduced the shear stresses in the foundation and decreased the vertical differential settlements at the top of the embank- ment. This influence was more pronounced as the tensile strength of the geotextile was increased.

• International Journal of Highway Engineering
• /
• v.11 no.1
• /
• pp.233-245
• /
• 2009

Availability of pressuremeter test for evaluation of geotechnical properties of foundation soil into which guardrail post is to be installed is investigated in this study. First, an analysis method of the post based on the pressuremeter test is proposed that can obtain bending moment and load-deformation profiles of the post. Then static horizontal load test onto a small scale guardrail post is performed in order to get bearing capacity and load-deformation pattern of the model post. The obtained results are compared with the load-deformation curves and bearing capacity of the post obtained from the pressuremeter method. In addition horizontal impact test to the post is performed using a model bogie car in order to check failure pattern around the model foundation and to investigate dynamic bearing capacity due to deceleration and inertia force of the soil. It is verified that the pressuremeter test is so useful and reasonal technique to analyze road foundation-post interaction.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.14 no.5
• /
• pp.1229-1241
• /
• 1994

This study aims at investigating the undrained behavior of the normally consolidated clay foundation using single hardening constitutive model based on elasticity and plasticity theories. The specimen employed was sampled at Mooan near the down stream of Young San river and remolded into consolidation apparatus. 11 soil parameters for the model was determined from simple tests such as isotropic compression and consolidation undrained triaxial compression tests. FEM program to predict the undrained behavior of the foundation was developed and back analysis was performed to verify prediction ability of the FEM program. Finally plate load test on the 2-dimensional model foundation was carried out in order to compare numerical analysis and observed values on the foundation.

• Geomechanics and Engineering
• /
• v.11 no.6
• /
• pp.805-820
• /
• 2016

A fully coupled non-linear effective stress response finite difference (FD) model is built to survey the counter-intuitive recent findings on the reliance of pore water pressure ratio on foundation contact pressure. Two alternative design scenarios for a benchmark problem are explored and contrasted in the light of construction emission rates using the EFFC-DFI methodology. A strain-hardening effective stress plasticity model is adopted to simulate the dynamic loading. A combination of input motions, contact pressure, initial vertical total pressure and distance to foundation centreline are employed, as model variables, to further investigate the control of permanent and variable actions on the residual pore pressure ratio. The model is verified against the Ghosh and Madabhushi high acceleration field test database. The outputs of this work are aimed to improve the current computer-aided seismic foundation design that relies on ground's packing state and consistency. The results confirm that on seismic excitation of shallow foundations, the likelihood of effective stress loss is greater in deeper depths and across free field. For the benchmark problem, adopting a shallow foundation system instead of piled foundation benefitted in a 75% less emission rate, a marked proportion of which is owed to reduced materials and haulage carbon cost.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2008.10a
• /
• pp.1144-1156
• /
• 2008

In this paper, heaving phenomenon is analyzed by laboratory tests. A laboratory test is consist of building soft clay foundation in plane-strain soil tank, construction of retaining wall, and excavation work. And range of shear strain, and destruction shape about soft clay foundation is compared, and analyzed with results of proposal formula. Using this study, safety factor is suggested for heaving phenomenon in the construction of wall on the soft clay. Actual theory is suggested by this suggested safety factor. There are various proposal formula for heaving phenomenon. For example, Terzaghi & Peck, Tschebotarioff, Bjerrum & Eide(Experience formula) and so on. Terzaghi & Peck's proposal formula is chosen, compared with laboratory test's result and analyzed in this study. A soft clay used in study is assumed homogeneous. A Depth of foundation is enough to observe shear strain by heaving phenomenon. Retaining wall is enough hard not to have vertical displacement.

• Korean Journal of Human Ecology
• /
• v.15 no.6
• /
• pp.1073-1081
• /
• 2006

The development of foundation garment pattern on the typical adult women's body was carried out. By means of the flatted body surface shell, the foundation garment pattern was developed. And its fitting test also performed. The results of this study can be summarized as follows; 1. The investigated Foundation basic pattern was made by the allowing the maximum bust size without any surplus since it was based on the tight-fitted model drawing technique. The investigated the completed pattern was designed in three parts of front and back body, including bust. 2. The result showed by overlapping the torso basic pattern foundation and body surface development selected from body almost the same except for the shift of dart position. 3. The result by overlapping basic pattern 3 existing basic patterns. On the basis of top-bust line showed that the setting up the volume of dart of bust and its waist affect the appearance of model. Especially, it was found that the above result was related to the bust and under bust line. 4. The result of the wearing test of 3 existing basic patterns and basic pattern of this study revealed that the mean values of whole items were higher than average in type P and type E. The fitting & position of under-bust line and extent of wrapping bust showed the high points in the current study and type of P. The result of evaluating the whole appearance in three points(front, side, back) showed different according to the every basic foundation garment pattern.

• Journal of the Korean Geotechnical Society
• /
• v.20 no.1
• /
• pp.131-139
• /
• 2004

When calculating bearing capacity and settlement of actual foundation from plate test result fur design and construction of shallow foundation, scale effect should be considered. But, adequate guide and test result of scale effect were not prepared yet in Korea. So, to analyze the relations of bearing capacity and settlement as the difference of loading plate sizes, model test and field loading test were performed with different loading plate on weathered-granite layer. Model tests were conducted with water content, compaction number, saturated unit weight and plate size(Dl5, 25cm) in soil-box$(2,000\times 2,000\times 1,000mm)$ formed soil layer. Field loading tests were carried out with diameters of loading plate$(D15, 25, 30, 40, 75\times 75, 140\times 210cm)$ on the same soil condition. Finally, we presented the prediction formula of bearing and settlement for computating scale offset in design of shallow foundation through result analysis of load test and numerical simulation on weathered soil and rock.