• Title/Summary/Keyword: Ground Condition

Search Result 2,222, Processing Time 0.027 seconds

A Study on the Quality Improvement of Housing Environment in Low-Income Families of Daejeon Area (대전지역 저소득층 주거환경의 질적인 개선에 관한 연구)

  • 이정희
    • Journal of the Korean Home Economics Association
    • /
    • v.28 no.2
    • /
    • pp.57-72
    • /
    • 1990
  • The purpose of this study were ; (1) to analyze the relationship between actual housing condition and housing satisfaction with socio-demographic and housing characteristics of respondents and (2) to present the device on the quality of housing environment in low-income families. The sample was a proportional, stratified, random sample of 299 low-income families in Deajeon. The major findings were as follows: 1) The wholey, actual housing conditions were not good; especially the worst conditions appeared exterior walls, roof, kitchen, bath and toilet, heating, noise, recreation facilities as play-ground. 2) Actual housing condition has been found to be related to income, tenure(rent or own), persons/room. In the relation of the socio-demographic and housing characteristics, actual housing condition, housing satisfaction, income and persons/room were found to be a significant explanatory variable in actual housing condition. And actual housing condition ws appeared to be the strongest variable in housing satisfaction. 3) Housing of the low-income families should be improved physical aspects of the environment and be reflected in need of the occupant that based on the social-welfare housing concept.

  • PDF

Field Evaluation of the Swelled Steel Tube Rockbolts (튜브형 강관 록볼트의 현장 적용성 평가)

  • Son, Sung-Gon;You, Jin-O;You, Joung-Hoon;Chung, Jae-Min
    • Proceedings of the KSR Conference
    • /
    • 2011.10a
    • /
    • pp.1149-1156
    • /
    • 2011
  • A rockbolt is one of the most important reinforcement of on-site soil, as with the shotcrete and steel rib. The rockbolt by setting within the tunnel can prevent the deformation of the ground profile; furthermore it improves the structural behavior of soil and rock. In general, the rockbolt is mainly used with reinforced steel. However, steel pipe or the materials with the same strength can be used depending on the soil conditions, ground water outflow condition, and the surrounding of applying location. In Korea, most tunnel construction sites have used cement mortar or resin for steel reinforcement on the rock. Due to the ground water outflow in the construction site, the usability of steel reinforcement is poor and it requires curing time especially after installation. To improve exist above problems, this study introduces the development of a swelled steel pipe rockbolt, as well as presents the field testing and performance results.

  • PDF

Probabilistic study of the influence of ground motion variables on response spectra

  • Yazdani, Azad;Takada, Tsuyoshi
    • Structural Engineering and Mechanics
    • /
    • v.39 no.6
    • /
    • pp.877-893
    • /
    • 2011
  • Response spectra of earthquake ground motions are important in the earthquake-resistant design and reliability analysis of structures. The formulation of the response spectrum in the frequency domain efficiently computes and evaluates the stochastic response spectrum. The frequency information of the excitation can be described using different functional forms. The shapes of the calculated response spectra of the excitation show strong magnitude and site dependency, but weak distance dependency. In this paper, to compare the effect of the earthquake ground motion variables, the contribution of these sources of variability to the response spectrum's uncertainty is calculated by using a stochastic analysis. The analytical results show that earthquake source factors and soil condition variables are the main sources of uncertainty in the response spectra, while path variables, such as distance, anelastic attenuation and upper crust attenuation, have relatively little effect. The presented formulation of dynamic structural response in frequency domain based only on the frequency information of the excitation can provide an important basis for the structural analysis in some location that lacks strong motion records.

Theoretical approach for ground behaviour during tunnelling in soils (토사터널굴진시 지반거동에 대한 이론적 접근에 대한 연구)

  • Kim, Sang-Hwan
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.5 no.4
    • /
    • pp.301-312
    • /
    • 2003
  • This paper considers the stresses and pore pressures induced in soft ground due to tunnelling and it presents and discusses the approach methods for estimating the stability of the tunnel and its heading during drained and undrained condition. In practical, the undrained analyses of the face stability of shield tunnelling in soft soil, are carried out based on the field data measured during tunnelling and the results are also evaluated.

  • PDF

A Case Study on Construction of a Tunnel Excavated in Silty Ground by the NATM (실트질 지반에 굴착된 NATM 터널의 시공사례 연구)

  • 박종호;윤효석;박종인;이원규
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 1999.10a
    • /
    • pp.139-146
    • /
    • 1999
  • Geological and geotechnical surveys, in general, should precede the excavation to ensure the stability of the tunnel md should be followed up according to the various geological condition during the excavation. However actually the standard support patterns which were decided during the design phases used be insisted for the whole excavation phases in spite of the various geological conditions. When $\bigcirc$$\bigcirc$ tunnel was excavated up to 25m long, the severe displacement was generated in the Portal area of $\bigcirc$$\bigcirc$ tunnel and the tunnel face was pally collapsed. Therefore, this paper present the case study on construction associated with the Umbrella Arch Method used in silty ground by the NATM.

  • PDF

Construction of Marine Small Hydro Power Plant using Discharge Water of Fish Farm (양어장 방류수를 이용한 해양소수력발전소 구축에 관한 연구)

  • Hwang, Yeong-Cheol;Choi, Young-Do
    • The KSFM Journal of Fluid Machinery
    • /
    • v.16 no.5
    • /
    • pp.11-17
    • /
    • 2013
  • This study is aimed to construct a marine small hydro power plant using discharge water of fish farm in Jeju Haengwon-ri. The difference of design methods between marine small hydro power plant and land small hydro power plant is to consider the tides. Moreover, ground condition should be examined because gushout sea water comes out from the ground at high tide in Jeju as the ground of Jeju beach consists of basalt stone. From the field test of the turbine generator after construction of the power plant, output power and efficiency of the turbine generator shows good conformance to the required conditions.

A Study of the Anchorage loss of Ground Anchor Using Spacing Apparatus and Spring (간격유치장치를 이용한 어스앵커 인장에 관한 연구)

  • Jeong, Sang-Min;Park, Young-Keun;Park, Moo-Kon;Kim, Kwang-Eok;Lee, Keun-Ho
    • Journal of the Korea Institute of Building Construction
    • /
    • v.5 no.4 s.18
    • /
    • pp.139-144
    • /
    • 2005
  • A ground anchor system is used as a load carrying element in soil work. The conventional systems with ground anthers bring about the anchorage loss of wedges when anchors are installed for the support of soil structures. Hence we developed the new type of anchor system using both the spacing apparatus and spring (length 60mm, diameter 6mm). In this system, we tan directly check the condition of wedges and PS strands and modify the problems with the slip and anchorage of wedges under construction. For demonstrating the superiority of this system, we carried out a series of the laboratory test. Consequently, we can obtain satisfactory result (18.99$\%$ reduction to the loss of conventional systems). Moreover, the replacement of wedges is easy and simple when retensioning of strands.

The Embedded Atom Method Analysis of the Palldium (Palladium의 Embedded Atom Method 개발)

  • 정영관;김경훈;김세웅;이성희;이근진;박규섭
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2002.05a
    • /
    • pp.652-655
    • /
    • 2002
  • The embedded atom method based on the density functional theory is used for calculating ground state properties of realistic metal systems. In this paper, we had corrected constitutive formulae and parameters on the palladium for the purpose of doing Embedded Atom Method analysis. And then we have computed the properties of the palladium on the fundamental scale of the atomic structure. In result, simulated ground state properties, such as the lattice constant, elastics constants and the sublimation energy, show good agreement with Daw's simulation data and with experimental data.

  • PDF

Vibration Loads on KSR-III during Ground Transportation and Handling (KSR-III 로켓의 도로운송 및 핸들링에 의한 진동하중)

  • Chun, Young-Doo;Cho, Byoung-Gyu;Park, Dong-Soo;Hwang, Seung-Hyun;Kim, Jhoon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2002.11b
    • /
    • pp.250-254
    • /
    • 2002
  • It is conducted to analyze vibration loads on KSR-III(KSR: Korea Sounding Rocket) and its major segments during their ground transportation and various handling process. These loads may be different from the real flight environment. Inadequate assessment of these loads can cause not only local damages on the rocket system but also the critical problem like flight mission failure. Therefore, transportation and handling loads must be considered during design and attenuated to ensure that the rocket structural damage does not occur. This work is concerned with the generation of criteria and prediction of transportation and handling loads for KSR-III. The results show that the shipping container is well designed to satisfy the design requirements. The maximum vibration level recorded during whole transportation and handling for KSR-III is less than 2g, the criteria of KSR-III movement condition.

  • PDF

Seismic performance of reinforced concrete shear wall buildings with underground stories

  • Saad, George;Najjar, Shadi;Saddik, Freddy
    • Earthquakes and Structures
    • /
    • v.10 no.4
    • /
    • pp.965-988
    • /
    • 2016
  • This paper investigates the seismic behavior of reinforced concrete shear wall buildings with multiple underground stories. A base-case where the buildings are modeled with a fixed condition at ground level is adopted, and then the number of basements is incrementally increased to evaluate changes in performance. Two subsurface site conditions, corresponding to very dense sands and medium dense sands, are used for the analysis. In addition, three ground shaking levels are used in the study. Results of the study indicated that while the common design practice of cropping the structure at the ground surface leads to conservative estimation of the base shear for taller and less rigid structures; it results in unpredicted and nonconservative trends for shorter and stiffer structures.