• 제목/요약/키워드: Excavation width

검색결과 111건 처리시간 0.026초

Study on bearing characteristic of rock mass with different structures: Physical modeling

  • Zhao, Zhenlong;Jing, Hongwen;Shi, Xinshuai;Yang, Lijun;Yin, Qian;Gao, Yuan
    • Geomechanics and Engineering
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    • 제25권3호
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    • pp.179-194
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    • 2021
  • In this paper, to study the stability of surrounding rock during roadway excavation in different rock mass structures, the physical model test for roadway excavation process in three types of intact rock mass, layered rock mass and massive rock mass were carried out by using the self-developed two-dimensional simulation testing system of complex underground engineering. Firstly, based on the engineering background of a deep mine in eastern China, the similar materials of the most appropriate ratio in line with the similarity theory were tested, compared and determined. Then, the physical models of four different schemes with 1000 mm (height) × 1000 mm (length) × 250 mm (width) were constructed. Finally, the roadway excavation was carried out after applying boundary conditions to the physical model by the simulation testing system. The results indicate that the supporting effect of rockbolts has a great influence on the shallow surrounding rock, and the rock mass structure can affect the overall stability of the surrounding rock. Furthermore, the failure mechanism and bearing capacity of surrounding rock were further discussed from the comparison of stress evolution characteristics, distribution of stress arch, and failure modes in different schemes.

The gob-side entry retaining with the high-water filling material in Xin'an Coal Mine

  • Li, Tan;Chen, Guangbo;Qin, Zhongcheng;Li, Qinghai;Cao, Bin;Liu, Yongle
    • Geomechanics and Engineering
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    • 제22권6호
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    • pp.541-552
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    • 2020
  • With the increasing tension of current coal resources and the increasing depth of coal mining, the gob-side entry retaining technology has become a preferred coal mining method in underground coal mines. Among them, the technology of the gob-side entry retaining with the high-water filling material can not only improve the recovery rate of coal resources, but also reduce the amount of roadway excavation. In this paper, based on the characteristics of the high-water filling material, the technological process of gob-side entry retaining with the high-water filling material is introduced. The early and late stress states of the filling body formed by the high-water filling materials are analyzed and studied. Taking the 8th floor No.3 working face of Xin'an coal mine as engineering background, the stress and displacement of surrounding rock of roadway with different filling body width are analyzed through the FLAC3D numerical simulation software. As the filling body width increases, the supporting ability of the filling body increases and the deformation of the surrounding rock decreases. According to the theoretical calculation and numerical simulation of the filling body width, the filling body width is finally determined to be 3.5m. Through the field observation, the deformation of the surrounding rock of the roadway is within the reasonable range. It is concluded that the gob-side entry retaining with the high-water filling material can control the deformation of the surrounding rock, which provides a reference for gob-side entry retaining technology with similar geological conditions.

영조 대 숭례문 문루의 하층 사용과 건축 변화에 대한 연구 (A Research on the Use and Architectural Changes of Sungnyemun in King Yeongjo's Reign)

  • 조상순
    • 건축역사연구
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    • 제21권3호
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    • pp.45-54
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    • 2012
  • This research work is to analyze architectural characteristics of Sungnyemun especially in King Yeongjo's reign in Joseon dynasty. The result of this research is summarized as following: 1. The architectural characteristics of Sungnyemun in King Yeongjo's reign are closely related with Confucian ceremonies such as Jeon-jwa and Heon-goek-rye. To perform these ceremonies, some lower walls of Sungnyemun's wooden pavilion were removed and used as ceremonial space. And after ceremony it was restored. 2. The floor type of center bay of the 1st story of wooden pavilion should have a type of floor using long and narrow fine tree plate, which is same type before the repair work of 1960's dismantlement. 3. The width of east stairway which is reached to east small gate, was changed just before Japanese's rule(1910~1945), should be broaden than present width, which is proven through the recent excavation. 4. The reason of asymmetric characteristic of locations of both east and west narrow-gate, and widths of east and west stairway, are related with order of King's ceremony. * Jeonjwa : a ceremony to see national affairs or receive royalty from officials in main hall or main gate of palace in Joseon dynasty (some times open to public) * Heon-goek-rye : a ceremony after win a war and offering to king enemy's ear or head in Joseon dynasty.

대형모형실험을 통한 수평 절리암반에서의 병설터널 이격거리 (Pillar Width of Twin Tunnels in Horizontal Jointed Rock Using Large Scale Model Tests)

  • 이용준;이상덕
    • 터널과지하공간
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    • 제20권5호
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    • pp.352-359
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    • 2010
  • 병설터널에서 근접 굴착으로 인한 영향은 터널간 이격거리에 따라 달라진다. 본 논문에서는 수평절리암반에 형성된 병설터널의 이격거리에 따른 영향을 파악하기 위하여 콘크리트 블록으로 균일 수평 절리 모형 지반을 조성하고 이격거리를 변화시키면서 모형터널을 설치한 후에 대형 모형실험을 수행하였다. 병설터널의 이격거리(필라폭)는 터널 폭 D를 기준으로 0.29D, 0.59D, 0.88D, 1.18D로 변화시켰다. 실험중에 필라 응력, 터널변위, 지반 변위를 계측하였다. 측압계수는 1.0을 유지하였다. 실험결과, 터널 및 주변지반의 변위와 필라 응력은 필라 폭이 감소함에 따라 증가하였다. 각 계측항목에서 최대 변화폭이 발생하는 단계는 후행터널의 상반굴착 직후로 나타났다. 병설터널 굴착 시 가장 큰 영향을 받는 위치는 필라부와 맞닿아 있는 선행터널의 어깨부로 확인되었다. 이러한 결과는 병설터널의 안정성은 시공 시 천단변위보다 내공변위 관리를 통해 평가되어야 한다는 것을 보여준다. 또한, 병설터널의 영향권이 양호한 지반조건에 대한 경험이론의 근접시공 영향권(0.8D~2.0D)보다 근접한 0.59D~0.88D 범위에서 형성되었으며 이러한 영향범위 감소는 병설터널의 안정성에 수평절리의 영향이 있는 것으로 판단된다.

팽창재료를 이용한 지하공동의 비개착식 긴급복구 공법에 대한 실내실험 및 수치해석 (Numerical Analysis and Laboratory Experiment of Rapid Restoration of Underground Cavity Using Expansive Material without Excavation)

  • 이기철;최병현;박종호;김동욱
    • 한국지반신소재학회논문집
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    • 제17권1호
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    • pp.55-64
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    • 2018
  • 본 연구에서는 최근 도심지에서 발생하고 있는 지반함몰에 대하여 팽창재료를 이용한 긴급복구공법을 적용하고 이러한 공법의 적합성을 수치해석적으로 판단하고자 한다. 수치해석에 적용된 팽창재료의 특성을 평가하기 위하여 실내실험을 수행하였다. 실험으로 구한 팽창특성을 반영하여 다양한 공동 형상(직사각형 단면을 가지는 공동에 대하여 다양한 높이와 폭 조합)에 대하여 팽창재료를 적용하였을 경우 팽창재료 및 지반 거동을 평가하였다. 해석 결과, 공동의 상단과 하단의 연직변위는 공동의 높이보다는 공동의 폭에 큰 영향을 받으며, 공동 측면부의 수평변위는 공동 폭 보다는 공동의 높이의 영향을 많이 받는 것으로 나타났다. 또한, 팽창압이 작용하였을 경우 도로상부 표층의 수직변위량은 공동의 높이보다는 공동의 폭에 큰 영향을 받는 것을 확인할 수 있었다.

대각선 병설터널 굴착에 따른 응력과 변위특성 (The Characteristics of Stress and Displacement due to the Diagonal Parallel Tunnel Excavation)

  • 김영수;박송자
    • 한국지반환경공학회 논문집
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    • 제12권11호
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    • pp.39-49
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    • 2011
  • 본 연구는 대각선 병설터널의 건설로 인한 응력과 변위 특성을 연구하였다. 이 연구에서 그 특성들이 터널의 직경(D)는 13m 그리고 지반은 풍화암으로 가정하여 해석하였다. 해석에서 pillar 폭은 2.0D, 2.5D, 3.0D, 토피고는 3D, 4D, 5D, 그리고 대각선 병설터널의 설치각도 $15^{\circ}$, $30^{\circ}$, $45^{\circ}$로 변화시켰다. 그리고 해석에 사용한 프로그램은 지반 공학적 문제해석에 널리 사용되고 있는 FLAC을 사용하여 발생하는 숏크리트 및 록볼트 응력과 주변지반 변위를 대각선 병설터널의 pillar 폭, 토피고, 그리고 설치각도에 따라 구하고 분석하였다. 그 결과 풍화암 지반에서는 pillar 폭 2.0D이상, 토피고 5.0D이상, 그리고 대각선 병설터널의 설치각도가 적을수록 주변 지반에 영향을 덜 미치고 터널의 안정에 유리한 것으로 나타났다.

지하철 대단면 터널의 설계와 시공관리 사례 (Design and Construction of a Large Section Tunnel for a Subway Station)

  • 문상조;장석부;정준화
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1999년도 봄 학술발표회 논문집
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    • pp.285-292
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    • 1999
  • Recent development cases of transportation utilities using tunnelling method in metropolitan sites have been increased due to the heavily complex environments and restrictions of construction works. The progress of tunnel design and construction to be supported by the tunnel analysis and measurement techniques using computers have increased adoptions of large section tunnels. In this paper, many factors to be considered in designing large section tunnels are discussed and the case of the construction of the subway station tunnel which is recently completed is introduced. This tunnel has a width of 24 m, a height of 16 m, and a excavation section area of 366 ㎡.

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황룡사 답도 연구 (A study on the Main-path Remains in the Hwangnyongsa Temple Site)

  • 김숙경
    • 건축역사연구
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    • 제25권3호
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    • pp.63-70
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    • 2016
  • This paper aimed to identify a main-path remains in the Hwangnyongsa temple site based on studying published the excavation survey report and researching relics related to the path in the ancient temple site. Hwngnyongsa temple, there were three type's paved footway, straight path to the central axis line of the layout, outside path around the main buildings and the front square of the lecture hall. These remains were expected that installed for some purposes, such as marches, touring, sort of a Buddhist ceremony been performed at the time of Silla. Straight path shows there were two rows of the main access inside the roofed corridor. A row consisted of the 2~3 pieces processed stone(Jangdaeseok) altogether with 92cm width and combined with square stone and stepping stone on the end of the road. It is regarded as very characteristic form and one of the architectural elements of Hwangnyongsa temple in Unified Silla period.

숭례문 지반 높이 변천과 홍예 비례 (On the Proportion of Sungnyemun Arch Related with the Changes of Ground Level)

  • 조상순;이상해
    • 건축역사연구
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    • 제21권4호
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    • pp.71-79
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    • 2012
  • The purpose of this research is to analyse the changes of ground level of Sungnyemun, the South Gate of Seoul City, and the principles of arch scale through the investigation based on the old records in Joseon dynasty. The result of this research is as follows: 1) The ground level of Sungnyemun, refers the level of foundation stone which was confirmed as original which is verified through the excavation conducted in 2005, maintained 1m's elevated level in 15~16 century and its elevated date presumed in King Sejong's reign(1418~1450). 2) The ground level of Sungnyemun is closely related with the royal funeral ceremony. 3) The width and height scale of Sungnyemun arch is about the ratio of 1 to 1. 4) During the Joseeon dynasty, Sungnyemun was referred as standard of other city wall gate. And it has similar architectural characteristics with Heunginjimun (or East Gate) of Seoul and Hwaseong Janganmun.

발파에 의한 터널 굴착시 RMR값에 따른 인접구조물의 동적 영향 (Dynamic Influence of Tunnel Blasting on Adjacent Structures for Various RMR Values)

  • 허재록;황의석;이봉열;김학문
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 봄 학술발표회 논문집
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    • pp.657-664
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    • 2002
  • This study presents the influence of blasting-induced vibration on the adjacent structures in rocks of various RMR values. 3D finite element analysis was performed to simulate the behaviour of tunnel and adjacent structures during rock excavation. The blast loadings were evaluated from the blasting pressure which is depending on the type and amount of explosive charges. Influencing factors for the stability of adjacent structures and ground conditions were reviewed in terms of structural dimensions and RMR values. The stiffness and load of adjacent structures are modeled in the numerical analysis to Investigate blasting effects of the size of adjacent structures. The vibration velocity and maximum particle velocity was increase sharply when the RMR value changed from 30 to 50. The effect of particle velocity was minimized at the width of structure become 2 times of tunnel diameter.

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