• Journal of The Geomorphological Association of Korea
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• v.25 no.4
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• pp.103-116
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• 2018

The purposes of this research are as follows: First, to reconstruct the optimal locational environment of the Bronze Age settlement in Cheonan Baekseok-dong (hereinafter referred to as the study settlement). Second, to identify the priority ranking of the topographical factors that influenced the Bronze Age people when selecting their the settlement location. For these reasons, the topographical factors of the 200 Bronze Age dwellings (hereinafter referred to as dwellings) confirmed in the survey area were analyzed through the ridge's environmental perspective. The results are asfollows: First, the optimal ridge environment of the Bronze Age settlement is largely a sub-ridge in N-S direction (for example, NNW-SSE, N-S, NNESSW), especially at the top (Crest slope, Crest flat) of the south-facing aspect of the ridge. Second, when the Bronze Age dwellers selected a residential location, they carefully considered topographical factors in the following order: (1) the slope direction of the ridge surface, (2) the micro-landform of the ridge, (3) the ridge scale, (4) the ridge direction, and (5) the surface relief. The results of this study could be used as basic data in related fields such as archaeology, quaternary research, and traditional architecture and so on.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1164-1169
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• 2009

Piled raft foundation is commonly used for structure on deep soft soil deposit rather than end bearing piles to control differential settlement. However, it is still expensive for light weight structures. Wing-wall type foundation has been successfully applied to reduce average settlement for light weight structure. This study will further investigate this type of foundation using bench scale experiments on clay and sand. Numerical analysis and approach method are used to verify load settlement curve of wing-wall foundation on experimentally study. Furthermore, normalized settlement curves are applied to define prediction of settlement on wing-wall foundation. In the result settlement on wing-wall foundation can be effectively done by increasing the length of wall instead of number of walls and equation for calculating average settlement can be derived using normalized load settlement curve.

• Journal of the Korean Geotechnical Society
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• v.28 no.6
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• pp.39-52
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• 2012

Magnetic sensing system and automated monitoring system based on digital hall sensor for ground settlement are developed to change traditional method for monitoring surface settlement and underground settlement by manual type and to overcome technical limits of existing automated settlement monitoring system. It's possible to monitor surface settlement and underground settlement with multi-points at the same time in a single hole with NX size. It was possible to verify technical confidence and stability by several case studies of soft ground improvement project.

• The Korean Journal of Malacology
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• v.21 no.1
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• pp.65-70
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• 2005

The purpose of this study is to determine the appropriate substrate for larval settlement and spat growth in the purple clam, Saxidomus purpuratus in laboratory culture. Larvae were reared with 3 different types of sediments (mud, sand, and mixed) for 46 days in settlement experiment, and settled spats were further grown in 3 types of sediments for 36 weeks in growth experiment. The density of settled spats in muddy sediments was more than 2 times higher than those in mixed or sandy sediments. But, the average size of settled spats in muddy sediments was smaller than those in mixed or sandy sediments. After 36 weeks of growth period, growth rate decreased as shell length increased. When shell length was less than 2 mm, growth rate in mixed sediments was significantly higher than that in sandy sediments. When shell length was more than 2 mm, there was no significant difference in growth rate among different substrates. Sediment type affected growth rate only when the spats were relatively small (less than 2 mm). Muddy sediments seems better for larval settlement, while mixed sediments is best for spat growth. We suggest the laboratory procedure for enhancing seedling production of S. purpuratus.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.430-440
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• 2009

Top-Base Foundation(TBF) was developed in Japan as a factory made concrete product. It is actively used in 6,000 sites by the end of 1980s in Japan and applied for a domestic patent in 1985. It is a shallow foundation whose effectiveness is proven by many relevant researchers and engineers. TBF was introduced to Korea in 1991 and has been applied mainly to architectural structures to date. Currently, the effectiveness in bearing capacity and settlement of TBF is being underestimated for civil engineering structures. Characteristics of Top-Base Foundation studied in Japan and Korea is known as follows: (1) as concrete part and crushed stone behave together, they perform the function of rigid mat; (2) the conical part and pile part of TBF disperses load by interaction with the crushed stone; (3) by preventing lateral strain and differential settlement on lower ground, it improves bearing capacity and constrains settlement at the same time. In Korea, it is used mostly in clayey soft grounds. The formula of bearing capacity and settlement of TBF suggested in Japan give the values of the underestimated. bearing capacity while its settlement is overestimated in comparison with the values measured from the field loading test. Therefore, in this study, the stress delivery mechanism of Top-Base Foundation developed in Japan and Floating Top Base developed in Korea is investigated through numerical analysis and laboratory model test.

• Journal of the Korean Society for Railway
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• v.18 no.4
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• pp.354-362
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• 2015

Since allowable settlement of concrete slab track is about 30mm, a lot of attention must be paid to the settlement of the earthwork (reinforced trackbed, upper subgrade, under subgrade) under the concrete track. To this end, more experimental data should be accumulated through tests for these materials. In this study, we evaluate the long-term settlement of reinforced trackbed and subgrade materials using factors such as repeated loading conditions, water content, and grain size distributions in a large triaxial test and a large oedometer test. In cases in which the performance of the reinforced trackbed layer meets the design criteria, the settlement caused by train load was considerably small. But, when the water content increases in the subgrade, unexpectedly large settlement might occur for certain grain size distributions of the subgrade materials.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.990-997
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• 2005

In this paper, the measured results obtained from the ground improved by SCP method at quay-wall caisson foundation in Pusan New Port 1-1 phase are analyzed and then compared with the values predicted by a consolidation theory. The measured settlement is generally smaller than the predicted settlement. For consolidation velocity, the measured velocity is later than the predicted value. According to the execution of caisson placing phases, the predicted value shows higher settlement than the measured one with time being.

• International Journal of High-Rise Buildings
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• v.6 no.1
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• pp.83-89
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• 2017

Due to the time-dependent properties of materials, structures, and loads, accurate time-dependent effects analysis and precise construction controls are very significant for rational analysis and design and saving project cost. Elevation control is an important part of the time-dependent construction control in supertall structures. Since supertall structures have numerous floors, heavy loads, long construction times, demanding processes, and are typically located in the soft coastal soil areas, both the time-dependent features of superstructure and settlement are very obvious. By using the time-dependent coupling effect analysis method, this paper compares Shanghai Tower's vertical deformation calculation and elevation control scheme, considering foundation differential settlement. The results show that the foundation differential settlement cannot be ignored in vertical deformation calculations and elevation control for supertall structures. The impact of foundation differential settlement for elevation compensation and pre-adjustment length can be divided into direct and indirect effects. Meanwhile, in the engineering practice of elevation control for supertall structures, it is recommended to adopt the multi-level elevation control method with relative elevation control and design elevation control, without considering the overall settlement in the construction process.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.457-467
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• 2010

The settlement prediction is very important to preloading method for a construction site on a soft ground. At the design stage, however, it is hard to predict the settlement exactly due to limitations of the site survey. Most of the settlement prediction is performed by a regression settlement curve based on the field data during a construction. In Korea, hyperbolic method has been most commonly used to align the settlement curve with the field data, because of its simplicity and many application cases. The results from hyperbolic method, however, may be differed by data selections or data fitting methods. In this study, the analyses using hyperbolic method were performed about the field data of $\bigcirc\bigcirc$ site in Pusan. Two data fitting methods, using an axis transformation or an alternative method, were applied with the various data group. If data was used only after the ground water level being stabilized, fitting results using both methods were in good agreement with the measured data. Without the information about the ground water level, the alternative method gives better results with the field data than the method using an axis transformation.

• Journal of the Korean Geosynthetics Society
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• v.22 no.1
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• pp.87-96
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• 2023

There are a lot of difference between the surface settlement and the differential settlement measured at the Busan New Port, where the dredged and reclaimed clay layer exists and below the clay is originally thickly distributed. To find the cause and solution of this, the actual conditions of each differential settlement used for the soft ground improvement, characteristics, installation method, measurement frequency, measurement data management, and data analysis of each type were considered. In the deep soft ground improvement work where large deformation occurs, the bending deformation of the screw-type differential settlement gauge is less than that of other types of measuring instruments, so there is less risk of loss, and the reliability of data is relatively high as the instruments are installed by drilling for each stratum. Since the greater the amount of high-precision settlement measurement data, the higher the settlement analysis precision. It is necessary to manage with higher criteria than the measurement frequency suggested in the standard specification. For the data management of the differential settlement gauge, it is desirable to create graphs of the settlement and embankment height of the relevant section over time, such as surface, differential, and settlement of pore water pressure gauge for each point. In the case of multi-layered ground with different compression characteristics, it is more appropriate to perform settlement analysis by calculating the consolidation characteristics of each stratum using a differential settlement data.