• Title/Summary/Keyword: hanging wall effect

Search Result 13, Processing Time 0.035 seconds

Effect of hanging-type sand fence on characteristics of wind-sand flow fields

  • Cheng, Jian-jun;Lei, Jia-qiang;Li, Sheng-yu;Wang, Hai-feng
    • Wind and Structures
    • /
    • v.22 no.5
    • /
    • pp.555-571
    • /
    • 2016
  • A hanging-type sand-retaining wall is a very common sand-blocking fence structure used to prevent sand movement. This type of wall is widely used along the Qinghai-Tibet and Gobi desert railways in Xinjiang, Western China. To analyze the characteristics of wind-sand flow fields under the effect of such a sand fence structure, a wind tunnel test and a field test were carried out. The wind tunnel test showed the zoning characteristics of the flow fields under the effect of the hanging-type sand-retaining wall, and the field test provided the sediment transport data for effective wind-proof interval and the sand resistance data in the front and behind the sand-retaining wall. The consistency of the wind-sand flow fields with the spatial distribution characteristic of wind-carried sand motion was verified by the correspondences of the acceleration zone in the flow field and the negative elevation points of the percentage variations of the sand collection rate. The spatial distribution characteristic of the field sand collection data further showed the spatial structural characteristic of the sandy air currents under the action of the hanging-type sand-retaining wall and the sand resistance characteristic of the sand-retaining wall. This systematic study on the wind-sand flow fields under the control of the hanging-type sand-retaining wall provides a theoretical basis for the rational layout of sand control engineering systems and the efficient utilization of a hanging-type sand-retaining wall.

Seismic responses of a metro tunnel in a ground fissure site

  • Liu, Nina;Huang, Qiang-Bing;Fan, Wen;Ma, Yu-Jie;Peng, Jian-Bing
    • Geomechanics and Engineering
    • /
    • v.15 no.2
    • /
    • pp.775-781
    • /
    • 2018
  • Shake table tests were conducted on scaled tunnel model to investigate the mechanism and effect of seismic loadings on horseshoe scaled tunnel model in ground fissure site. Key technical details of the experimental test were set up, including similarity relations, boundary conditions, sensor layout, modelling methods were presented. Synthetic waves and El Centro waves were adopted as the input earthquake waves. Results measured from hanging wall and foot wall were compared and analyzed. It is found that the seismic loadings increased the subsidence of hanging wall and lead to the appearance and propagation of cracks. The values of acceleration, earth pressure and strain were greater in the hanging wall than those in the foot wall. The tunnel exhibited the greatest earth pressure on right and left arches, however, the earth pressure on the crown of arch is the second largest and the inverted arch has the least earth pressure in the same tunnel section. Therefore, the effect of the hanging wall on the seismic performance of metro tunnel in earth fissure ground should be considered in the seismic design.

Noise Characteristics of Plumbing System with Wall Hanging Unit (층상배관 배수시스템의 소음 특성 평가)

  • Park, Cheol-Yong;Kim, Sang-Hoon;Jang, Dong-Woon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2006.05a
    • /
    • pp.1421-1424
    • /
    • 2006
  • Recently Requirement of indoor environment is increased in APT. Among indoor noises of APT, noise of plumbing system in bathroom is very serious problem except of floor impact noise. Plumbing system with wan hanging unit make a good grade and recognition in rating noise of bathroom in grade of house rating. But it is hard to find a data which are measured in APT built. In this study, the effect of noise reduction is checked by measuring the noise of plumbing system with wall hanging unit that is built. As result the upper household's Peak sound level is measured 80dB(A), the under household's peak sound level is measured 40dB(A).

  • PDF

Development and distribution of geo-hazards triggered by the 5.12 Wenchuan Earthquake in China

  • Runqiu, Huang;Weile, Li
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2009.03a
    • /
    • pp.1225-1234
    • /
    • 2009
  • As the Wenchuan Earthquake was of high magnitude and shallow seismic focus, it caused great damage and serious geo-hazards. By the field investigation and remote-sensing interpretation after the earthquake and by using means of GIS, the distribution of geo-hazards triggered by the earthquake was analyzed and the conclusions are as follows: (1) the earthquake geo-hazards showed the feature of zonal distribution along the earthquake fault zone and linear distribution along the rivers; (2) the distribution of earthquake geo-hazards had a marked hanging wall effect, for the development density of geo-hazards in the hanging wall of earthquake fault was obviously higher than that in the foot wall and the width of strong development zone in the hanging wall was about 10 km; (3) the topographical slope was a main factor which controlled the development of earthquake geo-hazards and a vast majority of geo-hazards were distributed on the slopes of 20 to 50 degrees; (4) the earthquake geo-hazards had a corresponding relationship with the elevation and micro-landform, for most hazards happened in the river valleys and canyon sections below the elevation of 1500 to 2000 m, particularly in the upper segment of canyon sections (namely, the turning point from the dale to the canyon). Thin ridge, isolated or full-face space mountains were most sensitive to the seismic wave, and had a striking amplifying effect. In these areas, collapses and landslides were most likely to develop; (5) the study also showed that different lithologies determined the types of geo-hazards, and usually, landslides occurred in soft rocks, while collapses occurred in hard rocks.

  • PDF

Primary Dispersion Patterns and Widths of Elements in Altered Granitic Wallrock around the Gold-bearing Quartz Veins at the Mugeug Mine (무극 함금석영맥광상 화강암질모암에서의 원소들의 분산형태와 분산범위)

  • Hwang, In Ho;Chon, Hyo Taek
    • Economic and Environmental Geology
    • /
    • v.27 no.5
    • /
    • pp.451-458
    • /
    • 1994
  • Geochemical studies on gold-bearing quartz veins and granitic wallrocks from the Mugeug mine were carried out in order to investigate primary dispersion patterns of elements and to quantify primary dispersion widths of elements with distance from the gold-bearing quartz veins. The best fitting model of dispersion pattern in altered wallrock around the gold-bearing quartz veins is an exponential function for Au, As, Sb, $Na_2O$ and Sr, and a quadratic function for CaO, $K_2O$, MnO, Ba, Rb and Cs. The primary dispersion widths are 15~343 cm in the hanging wall, and 33~173 cm in the footwall. The width of primary dispersion in the hanging wall is twice as thick as that in the footwall mainly due to the thermal effect and volatile components. The primary dispersion width is increased as the increase of gold-bearing quartz vein width and contents of As and Sb in gold-bearing quartz veins, but is not related to Au content in gold-bearing quartz veins.

  • PDF

Experimental research on the evolution characteristics of displacement and stress in the formation of reverse faults

  • Chen, Shao J.;Xia, Zhi G.;Yin, Da W.;Du, Zhao W.
    • Geomechanics and Engineering
    • /
    • v.23 no.2
    • /
    • pp.127-137
    • /
    • 2020
  • To study the reverse fault formation process and the stress evolution feature, a simulation test system of reverse fault formation is developed based on the analysis of reverse fault formation mechanism. The system mainly consists of simulation laboratory module, operation console and horizontal loading control system, and data monitoring system. It can represent the fault formation process, induce fault crack initiation and simulate faults of different throws. Simulation tests on reverse fault formation process are conducted by using the simulation test system: horizontal loading is added to one side of the model. the bottom rock layer cracks under the effect of the induction device. The crack dip angle is about 29°. A reverse fault is formed with the expansion of the crack dip angle towards the upper right along the fracture surface and the slippage of the hanging wall over the foot wall. Its formation process unfolds five stages: compressive deformation of rock, local crack initiation, reverse fault penetration, slippage of the hanging wall over the foot wall and compaction of fault plane. There is residual structural stress inside rock after fault formation. The study methods and results have guiding and referential significance for further study on reverse fault formation mechanism and rock stress evolution.

Development and application of a STEAM program using classroom wall gardens

  • Kwack, Hye Ran;Jang, Eu Jean
    • Journal of People, Plants, and Environment
    • /
    • v.24 no.4
    • /
    • pp.365-376
    • /
    • 2021
  • Background and objective: This study aims to develop and apply programs in agriculture and life sciences for promoting divergent thinking in STEAM using classroom wall gardens. The process of the STEAM program such as presentation of the situation, creative design, and success experience is proposed to utilize STEAM education as a distinguished program. Methods: Four types of classroom wall gardens were used in this program, such as the 'plaster pot wall garden', 'attachable LED wall garden'. 'coffee pack wall garden', and 'hanging wall garden' for each classroom. For this purpose, official letters were sent to relevant institutions (elementary schools) specified by the research institute, and classes were conducted on the selected elementary school students. Results: A satisfaction survey and effect analysis were conducted on the students participating in the program. The program was designed to take a total of 11 hours, comprised of teaching plans including the topics, purpose of production, subject outlines, learning goals, and elements of STEAM subjects and stages. Conclusion: According to the survey on student satisfaction and understanding, it was found that students participating in the program have a high level of understanding and participation, as well as increased interest in science. Also, the program helped the students to connect with other subject areas. The level of student satisfaction was especially high in the upper grades. It is believed that the results of this research contribute to the development of STEAM education programs in agriculture and life sciences as well as other subject areas.

Numerical simulation on mining effect influenced by a normal fault and its induced effect on rock burst

  • Jiang, Jin-Quan;Wang, Pu;Jiang, Li-Shuai;Zheng, Peng-Qiang;Feng, Fan
    • Geomechanics and Engineering
    • /
    • v.14 no.4
    • /
    • pp.337-344
    • /
    • 2018
  • The study of the mining effect influenced by a normal fault has great significance concerning the prediction and prevention of fault rock burst. According to the occurrence condition of a normal fault, the stress evolution of the working face and fault plane, the movement characteristics of overlying strata, and the law of fault slipping when the working face advances from footwall to hanging wall are studied utilizing UDEC numerical simulation. Then the inducing-mechanism of fault rock burst is revealed. Results show that in pre-mining, the in situ stress distribution of two fault walls in the fault-affected zone is notably different. When the working face mines in the footwall, the abutment stress distributes in a "double peak" pattern. The ratio of shear stress to normal stress and the fault slipping have the obvious spatial and temporal characteristics because they vary gradually from the higher layer to the lower one orderly. The variation of roof subsidence is in S-shape which includes slow deformation, violent slipping, deformation induced by the hanging wall strata rotation, and movement stability. The simulation results are verified via several engineering cases of fault rock burst. Moreover, it can provide a reference for prevention and control of rock burst in a fault-affected zone under similar conditions.

A theoretic study about western traditional wallpaper hanging (서양의 전통도배에 관한 이론적 고찰)

  • Lim, Sun-Yang
    • Archives of design research
    • /
    • v.19 no.2 s.64
    • /
    • pp.207-216
    • /
    • 2006
  • Even though the notion exists that wall paper has got a short durability for interior decoration in terms of paper's nature, it can be the most important element among the modern dosing wall papering because of the variation of the walls visual effect. Wall paper hasn't been preserved well according to the paper's character and official records haven't been done well. So, by studying a case in which a room is maintained well, seeing various commercial samples which were used for an advertisement and reading several booklets it is possible to study historical evidence. In regard to wall paper and Papering. data, the commercial historic nature of the traditional wall papering has been recognized again in order to study the root of the technical and commercial background. In theory, the historic background research of traditional wall paper in the past is said to have established its theoretical system and the development of modern wall papering in the middle of Britain in 18th century. Through the theoretical study of wall papering, the following things have been researched: handling don the method of the traditional wall papering and lining paper, stylization of pattern by using the method of continual linking, subdivision of commercial cost and specialization of wallpaper, handing down the past traditional adhesion method, the origin of string wallpaper, utility of traditional wallpaper and its various abilities, the change from the face to face linking to duplicated linking, the development of DIY products by women's wallpaper selections. Put against other materials, wallpaper remains the most popular and preferable product for managing a wall and provides a decorative, wall dosing technique. This study can estimate the source of wallpapering history in order to create a systemic approach towards the future's wallpaper industry. This is very important data in order to establish a theoretical system of traditional wallpapering according to its historical research about wallpapering skills and its commercial aspect.

  • PDF

Shaking table test on seismic response and failure characteristics of ground fissures site during earthquakes

  • Chao, Zhang;Xuzhi, Nie;Zhongming, Xiong;Yuekui, Pang;Xiaolu, Yuan;Yan, Zhuge;Youjun, Xu
    • Geomechanics and Engineering
    • /
    • v.32 no.3
    • /
    • pp.307-319
    • /
    • 2023
  • Ground fissures have a huge effect on the integrity of surface structures. In high-intensity ground fissure regions, however, land resource would be wasted and city building and economic development would be limited if the area avoiding principle was used. In view of this challenge, to reveal the seismic response and seismic failure characteristics of ground fissure sites, a shaking table test on model soil based on a 1:15 scale experiment was carried out. In the test, the spatial distribution characteristics of acceleration response and Arias intensity were obtained for a site exposed to earthquakes with different characteristics. Furthermore, the failure characteristics and damage evolution of the model soil were analyzed. The test results indicated that, with the increase in the earthquake acceleration magnitude, the crack width of the ground fissure enlarged from 0 to 5 mm. The soil of the hanging wall was characterized by earlier cracking and a higher abundance of secondary fissures at 45°. Under strong earthquakes, the model soil, especially the soil near the ground fissure, was severely damaged and exhibited reduced stiffness. As a result, its natural frequency also decreased from 11.41 Hz to 8.05 Hz, whereas the damping ratio increased from 4.8% to 9.1%. Due to the existence of ground fissure, the acceleration was amplified to nearly 0.476 m/s2, as high as 2.38 times of the input acceleration magnitude. The maximum of acceleration and Arias intensity appeared at the fissure zone, which decreased from the main fissure toward both sides, showing hanging wall effects. The seismic intensity, duration and frequency spectrum all had certain effects on the seismic response of the ground fissure site, but their influence degrees were different. The seismic response of the site induced by the seismic wave that had richer low-frequency components and longer duration was larger. The discrepancies of seismic response between the hanging wall and the footwall declined obviously when the magnitude of the earthquake acceleration increased. The research results will be propitious to enhancing the utilizing ratio of the limited landing resource, alleviation of property damages and casualties, and provide a good engineering application foreground.