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1.
Performance of Mortar and Chemical Grout Injection into Surrounding Soil When Slurry Pipe-jacking Method is Used 总被引:1,自引:0,他引:1
Hideki Shimada Takashi Sasaoka Saeid Khazaei Yasuhiro Yoshida Kikuo Matsui 《Geotechnical and Geological Engineering》2006,24(1):57-77
Small-diameter shallow tunnels are often being built by using the slurry pipe-jacking method. This system involves the pushing
or thrusting of a drivage machine and concrete pipes into the ground. Chemical grout injection into the surrounding soil around
the tunnel is carried out after the drivage and pushing processes are finished. The purpose of the chemical grout injection
is to maintain permanent stability of the surrounding soil. However, the behavior of the chemical grouting material in the
surrounding soil around the tunnel and the amount of optimum injection is not clearly understood. From these points of view,
this paper discusses the performance of the chemical grouting material, when it is injected into the surrounding soil around
the tunnel, by means of 2-D Eulerian–Lagrangian seepage analysis. Moreover, the effectiveness of the chemical grout injection
was evaluated by using the non-linear finite element method. This investigation show when the range of the grouted zone is
designed; it is necessary that the relationship between Young’s modulus of the soil/grouted zone and the confining stress
be taken into consideration in order to establish effective, economical and safe chemical grout injection system. Understanding
the performance of the seepage/dispersion behavior of the chemical grout and the characteristics of soil/ grouted zone is
also important. 相似文献
2.
Monitoring of Over Cutting Area and Lubrication Distribution in a Large Slurry Pipe Jacking Operation 总被引:1,自引:0,他引:1
Saeid Khazaei Hideki Shimada Takashi Kawai Junichi Yotsumoto Kikuo Matsui 《Geotechnical and Geological Engineering》2006,24(3):735-755
Slurry pipe jacking was firmly established as a special method for the non-disruptive construction of the underground pipelines
of sewage systems. Pipe jacking, in its traditional form, has occasionally been used for short railways, roads, rivers, and
other projects. Basically the system involves the pushing or thrusting of concrete pipes into the ground by a number of jacks.
In slurry pipe jacking, during the pushing process, mud slurry and lubricant are injected into the face and the over cutting
area that is between the concrete pipes and the surrounding soil. Next, the slurry fills voids and the soil stabilizes due
to the created slurry cake around the pipes. Fillings also reduce the jacking force or thrust during operation. When the drivage
and pushing processes are finished, a mortar injection into the over cutting area is carried out in order to maintain permanent
stability of the surrounding soil and the over cutting area. Successful lubrication around the pipes is extremely important
in a large diameter slurry pipe jacking operation.
Control of lubrication and gaps between pipes and soil can prevent hazards such as surface settlement and increases in thrust.
Also, to find voids around the pipes after the jacking process, in order to inject mortar for permanent stabilizing, an investigation
around the pipes is necessary. To meet these aims, this paper is concerned with the utilization of known methods such as the
GPR (Ground Penetrating Radar) system and borehole camera to maintain control of the over cutting area and lubricant distribution
around the pipes during a site investigation. From this point of view, experiments were carried out during a tunnel construction
using one of the largest cases of slurry pipe jacking in Fujisawa city, Japan. The advantages and disadvantages of each system
were clarified during the tests. 相似文献
3.
Natural Resources Research - The quality of surface waters plays a key role in the sustainability of ecological systems. Measuring water quality parameters (WQPs) is of high... 相似文献
4.
Increasing population in urban areas and limitations of suitable lands for developing houses and urban infrastructure have led to the vertical development in cities. However, these developments are managed by a cadastral system which is mainly two-dimensional and cannot efficiently represent Rights, Restrictions, and Responsibilities (RRRs) in complex scenarios. In fact, a three-dimensional cadastre is required for efficiently registering and representing RRRs. In this paper, a 3D proximity analysis was proposed and implemented to determine RRRs and associated easement rights in non-topology-based data structures. This method can be used to investigate the surrounding spaces of a subject apartment unit or storage in a high-rise. The performance of the developed method was evaluated in a large complex high-rise in Tehran, Iran. The results confirmed that the proposed method can correctly identify the neighbor spaces in complex scenarios. 相似文献
5.
Vahid Toufigh Farnam Saeid Ahad Ouria Chandrakant S. Desai Hamid Saadatmanesh 《Geomechanics and Geoengineering》2014,9(3):208-214
Soil is a material which is weak in tension; however, different materials such as geotextiles are used to address this inadequacy. In recent years more than one million square metres of geotextiles were used for reinforcing soil. Nevertheless, there are several significant problems associated with geotextiles, such as creep, low modulus of elasticity and susceptibility to aggressive environments. Carbon fibre reinforced polymer (CFRP) was introduced over two decades ago to the field of structural engineering and it can also be used in geotechnical engineering. CFRP has all the benefits associated with geotextiles and it boasts a higher strength, higher modulus, no creep and reliability in aggressive environments. In this investigation, the interface properties of CFRP-sand and fine sand were investigated using the pull-out test. The pull-out test device was designed and assembled using a triaxial loading device and a direct shear device. In the pull-out test, the normal force applied by the triaxial loading and pull-out force is applied by a direct shear device. CFRP samples were prepared in the lab. Precast and cast-in-place samples were tested. The pull-out force and corresponding displacements of each of the materials were recorded and compared. 相似文献
6.
Lashkari Ali Shourijeh Piltan Tabatabaie Khorasani Seyed Saeid Sahebkar Irani Nazanin Rahman Md. Mizanur 《Acta Geotechnica》2022,17(11):4989-5007
Acta Geotechnica - This article presents an experimental program under the constant volume condition to investigate the influence of over-consolidation on flow instability of clean and silty sand... 相似文献
7.
Ghorbanzadeh Omid Shahabi Hejar Crivellari Alessandro Homayouni Saeid Blaschke Thomas Ghamisi Pedram 《Landslides》2022,19(4):929-939
Landslides - Recent landslide detection studies have focused on pixel-based deep learning (DL) approaches. In contrast, intuitive annotation of landslides from satellite imagery is based on... 相似文献
8.
Parisa?Almasi Saeid?SoltaniEmail author 《Stochastic Environmental Research and Risk Assessment (SERRA)》2017,31(5):1171-1182
The present study attempts to investigate potential impacts of climate change on floods frequency in Bazoft Basin which is located in central part of Iran. A combination of four general circulation models is used through a weighting approach to assess uncertainty in the climate projections. LARS-WG model is applied to downscale large scale atmospheric data to local stations. The resulting data is in turn used as input of the hydrological model Water and Energy Transfer between Soil, plants and atmosphere (WetSpa) to simulate runoff for present (1971–2000), near future (2020–2049) and far future (2071–2100) conditions. Results demonstrate good performance of both WetSpa and LARS-WG models. In addition in this paper instantaneous peak flow (IPF) is estimated using some empirical equations including Fuller, Sangal and Fill–Steiner methods. Comparison of estimated and observed IPF shows that Fill–Steiner is better than other methods. Then different probability distribution functions are fit to IPF series. Results of flood frequency analysis indicate that Pearson III is the best distribution fitted to IPF data. It is also indicated that flood magnitude will decrease in future for all return periods. 相似文献
9.
Saeideh Maleki Alireza Soffianian Saeid Soltani Koupaei Sassan Saatchi Saeid Pourmanafi 《Journal of the Indian Society of Remote Sensing》2018,46(11):1871-1879
Monitoring wetland as one of the important parts of the global ecosystem is necessary for conservational programs. But, usually, collecting in situ data is restricted in these areas because of their remote locations, vast area and dynamic conditions. Remote sensing provides a cost effective tool to investigate hydrological patterns and the seasonal trend of changes in wetlands. In this paper, Land-use/land-cover change during water inundation period of Hamun wetland was investigated in order to determine change trend during this period. Hamun wetland is an unsustainable ecosystem, and monitoring this wetland is essential for conservation goals. This trend is critical for decision makers in order to plan the conservational scheme in all unsustainable ecosystems. To reach this objective, the land-use/land-cover maps during inundation period of Hamun were produced using Landsat 8 time series images. The results of accuracy assessment showed the classification of water and vegetation have the highest accuracy (94% and 93%, respectively). And the accuracy of plants in the water classes was the lowest (water–veg?=?89.9%, veg–water 1?=?88.8%, veg–water 2?=?87.6%). This means the higher misclassification is in determining the vegetation in the water. Then, the changes in the land-cover classes in relation to wetland inundation were investigated. Results of land-use/land-cover change illustrate the regions that were suitable for water birds but lost their suitability when the wetland dried out. These areas are crucial for water bird’s conservation. Satellite data determined these areas with acceptable accuracy. 相似文献
10.
Esmaeiloghli Saeid Tabatabaei Seyed Hassan Carranza Emmanuel John M. Hosseini Shahram Deville Yannick 《Natural Resources Research》2021,30(6):3925-3953
Natural Resources Research - This contribution proposes a spatially weighted factor analysis (SWFA) to recognize effectively the underlying mineralization-related feature(s) in geochemical signals.... 相似文献