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20 April 2016, Volume 30 Issue 2 Previous Issue    Next Issue

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Applications of Grouting Method in the Treatment of the Mined Area of a Coal Mine YU Lianshun1, WANG Zong2, CHANG Hongshuai2, LIU Li3 2016, 30 (2):  115-118.  Abstract ( 1543 )   Save This paper presents a case history of the mined area treatment of a coal mine.  The design grouting scheme for the treatment was selected based on the specific conditions of the mined area and the site subsurface conditions. Details of the grouting design and the measures for dealing with the adverse conditions during the grouting process are also introduced. The test boring, water pumping and crosshole CT scanning techniques were used to verified the grouting results. The testing results indicated that the goals were achieved. Related Articles | Metrics

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Investigation and Mitigation Design for a Landslide in the Soil Rock Mixtures ZHOU Ren，NIU Guanchao, GUO Peixi 2016, 30 (2):  119-122.  Abstract ( 1545 )   Save A detailed geotechnical investigation was performed on a landslide in the soil and rock mixture slope. The characterization of the landslide and the triggering factors were able to be identified. The investigation results concluded that two relatively independent landslides, namely, HP1 and HP2, existed in the system. Slide HP1 had a slip surface along the interface of soil and rock, whereas, Slide HP2 had a planar slip surface along the weak layer in the bedrock. The landslide mitigation program was therefore determined. Within the HP1 and HP2 slides, a combination of benching the slope, grid beam with ground anchors and drainage ditches was proposed. The large diameter drilled pier to resist the slide was also used in Slide HP2. The "m" method was able to be applied in the antislide drilled pier design. Related Articles | Metrics

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Characterization and Mitigation of the Longjiayan Multi-Staged Landslide WU Weiyi1,2 2016, 30 (2):  123-126.  Abstract ( 1499 )   Save The conventional design methods for estimating the sliding forces in the multistaged landslides are usually over conservative due to their complexity. As a result of the excessively large driving forces, the mitigation scheme usually becomes very difficult. This paper presents a case history of the Longjiayan landslide mitigation. The landslide characterization was performed and the multistaged mitigation program was selected based on the stability analysis results. The drilled piers were utilized to resist the potential sliding and the performance of the "h" typed drilled piers was analyzed by using the commercial finite element software ANSYS. Related Articles | Metrics

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Stability Analysis of a Landslide in Fengjie Eco-Friendly Immigration Industrial Park YU Zhi， MAO Chengwen 2016, 30 (2):  127-130.  Abstract ( 1415 )   Save The Sunjiawan Landslide is occurred in the EcoFriendly Immigration Industrial Park in Fengjie County, Chongqing City. It is located at the right bank of the Shima River which is a tributary of the Caotang River. The landslide location is also within the operational pool water level. The triggering factors of the landslide were evaluated based on the geotechnical, physiographical and hydrological investigations and the stability was analyzed at cross section SJW33 by using a commercial software. The results indicate that the slope could be stable at the normal operation conditions, however, Local failure at the existing landslide when a rapid drawdown condition occurred at a pool water level elevation of 175 m. Under the extreme conditions, circular failure mode might be triggered. Appropriate engineering mitigation measures are necessary. Related Articles | Metrics

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Case History of Stability Evaluation of Soil Slopes with Coal Lenses ZHENG Yichen1,2, ZHANG Keneng1,2 2016, 30 (2):  131-135.  Abstract ( 1278 )   Save The slope stability (landslide) related geohazards are frequently encountered in the projects in the development of the Chenzhou area. One of the most frequently occurred instabilities in the project developments occurred in soil slopes with coal mine lens. The soil slopes with coal mine lenses have the characteristics of unevenly distributed stiffness among different strata; poor cementation between different soil layers, loose in density; prone to slaking in the ambient air and water; unstable properties in strength and in the fabrics. This paper summarizes the experience grain from the stability evaluation projects in soil slopes with coal mine lenses. The failure modes of the coal mine lens slopes and their influence factors are also presented in the paper. A landslide mitigation project at Tongxinqiao is presented in the paper. The optimized scheme is focused on the "prevention" of the instability in additional to the "remediation". Related Articles | Metrics

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Evaluation and Remediation of a Landslide at the South Side of an Open Pit Mine CUI Feng 2016, 30 (2):  136-139.  Abstract ( 1427 )   Save The landslide is a frequent geological hazards in the open pit mines die to the high and steep excavation slopes as well as the vibrations induced by the blasting. The debris from the landslide are usually consisted of a wide range of grain sizes and loose materials. As a result, the stability of the debris from the landslide area is usually very poor and the remediation of these loosely piled debris is necessary for a safe operation of the mining. This paper presents a case history of the evaluation and mitigation of a failed open pit mine slope. Site investigations were performed to characterize the subsurface conditions as well as to obtain the analytical parameters. Threedimensional laser scanning technology was used to precisely obtaining the topographical information of the sliding body. Three dimension numerical slope stability analysis was performed by using the commercial software FLAC3D. It was concluded that the targeted body was unstable and the remediation is required. The mitigation scheme included flattening unloading the slope. The remediated slope was evaluated and a satisfactory result was obtained. Related Articles | Metrics

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Evaluation of a Distressed Reinforced Earth Gravelly Soil Slope WANG Zongkui, JIANG Zhiquan 2016, 30 (2):  140-143.  Abstract ( 1294 )   Save This paper presents a case history of evaluating a distressed reinforced soil slope and its possible failure modes. The field investigation, insitu and laboratory tests were performed to characterize the subsurface conditions and geotechnical properties of various soil strata. A two dimensional numerical slope stability analytical model under the seepage conditions was established by using Geostudio software. The stability analyses were performed under both normal operation conditions and extreme conditions. The various failure modes are summarized in the paper based on the analytical results.\= Related Articles | Metrics

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Support Design and Environmental Impact Assessment of a Deep Excavation ZHAN Ke, HAN Aiguo， ZHANG Xiaolin 2016, 30 (2):  144-147.  Abstract ( 1219 )   Save This paper presents a case history of a deep excavation in Shanghai. Based on the subsurface conditions of the proposed deep excavations, both gravity wall type and soil mixed wall (SMW) were used as the supporting structures. The excavation process, the performance of the supporting structures and the impact on the adjacent structures were numerically simulated by the finite element method. The results indicate that gravity wall and SMW are suitable as the supporting structures of the deep excavation. Related Articles | Metrics

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Analysis and Remediation of the Large Deep Excavation on the Adjacent Operational Tunnel  ZHAO Jing 2016, 30 (2):  148-151.  Abstract ( 1291 )   Save This paper presents a case history of the impact of a large deep excavation in Suzhou soft soils on the adjacent operational tunnels. The remediation measures are optimized in both design and construction. The soil parameters used in the analytical model were determined by the back analysis and the calibrated parameters were used in the performance of the operational tunnel during the entire deep excavation process. The numerical analysis results indicate that, the remediation measures used in the construction is effective and the impact of the deep excavation on the adjacent operational tunnel is acceptable. Related Articles | Metrics

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Foundation Pit Supporting Technology of Reconstruction and Expansion Engineering in the Older Sections of Beijing ZHANG Lue1, WEI Fengxian2, GUO Yixian1 2016, 30 (2):  152-156.  Abstract ( 1127 )   Save Deep excavation supporting design and construction in the urban areas might be frequently encountered many challenges, such as, underground utilities and structures; narrow sites; potential impact to the adjacent buildings and structures. This paper presents a case history of deep excavation design and construction in the confined spaces: All China Woman Federation office building expansion project. The excavation supporting design utilizes the existing structures to serves as the supporting structure. The existing reinforced basement wall and the new cast in place piles are combined in the design. The performance of the new piles and the existing concrete wall are numerically simulated by using MIDAS GTS NX. The numerical analysis and the construction monitoring results indicate that, ⑴ the combined supporting structure had very small lateral deflections and these lateral deflections are far less than the allowable values in the design codes. ⑵ the finite element analysis results were consistent with the monitored values. The numerical analysis can be used to predict the performance of the entire excavation and to predict the behavior of a concerned structure element. Related Articles | Metrics

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Large Displacements in a Soft Soil Embankment Treated by Pipe Piles ZHANG Ke1, XU Faming2 2016, 30 (2):  157-160.  Abstract ( 1456 )   Save This paper presents a case history of the ground improvement monitoring results in the mountain area of Guangdong Province. The expressway embankment over the soft soils was improved by the pipe piles. When the embankment height was only 4.97 meters, the observed maximum vertical settlement was 443 millimeters and the maximum lateral deflection was 168 millimeters. Additional geotechnical investigations by the cone penetrometer testing were performed and the stability of the embankment was reevaluated. The ultimate vertical settlement and lateral movement were predicted. The results indicate that, the ultimate vertical and lateral deformations are within the controllable range. From the monitored data, the embankment deformation rate have the characterization of rapid in the initial stage and would gradually reduce the rate. Related Articles | Metrics

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Bearing Behavior of an Aged Municipal Landfill in Wuhan JIANG Shanchao， WEN Songlin, REN Jiali 2016, 30 (2):  161-163.  Abstract ( 1223 )   Save The reutilization of the capped and aged municipal landfills becomes more and more urgent due to the limited land resource. Due to its highly heterogeneous in nature, the aged municipal landfills is a special soil with high variable compressibility. The bearing capacity characterization of the aged municipal landfill soils was evaluated through the field plate loading tests as well as the numerical analysis. The results indicate that, when the loading level is low, a high compressibility was demonstrated. When the loading level is higher, the fibrous components in the landfill served as reinforcement, a lower compressibility could be obtained. The entire stress strain curve can be divided into four different stages and it can be fitted using the the curves suggested by Konder. Related Articles | Metrics

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Settlement of Building Induced by the Adjacent Shielded Tunnel Excavation in the Saturated Weak Soils HUA Zhigang 2016, 30 (2):  164-167.  Abstract ( 1132 )   Save This paper presents a case history of the shielded tunnel excavation in the saturated weak soils in Suzhou Metro #4 Line. The twin tunnel tubes were underneath a masonry building structure. During the tunnel excavation, the deflections at the ground surface and the building structure were monitored. The results indicate that, when the blade was in the range of 18 m to 5 m to the monitored point, a vertical settlement of 2 millimeters was observed. A ground heave of 0.5 ot 1.0 millimeter could be monitored when the shielded blade is zero to 5 meters to the survey point. A fast deformation rate was observed when the blade is reached the monitored point and the deformation became stable one or two days after the excavation. The settlement control would be different if the saturated weak soil were disturbed. An increase in settlement at the ground surface and the building if the shielded excavation was stopped. Due to its poor stiffness, large differential settlement was observed in the masonry building. If the tunnel was under one side of the masonry building, tilting in the building could be observed. Related Articles | Metrics

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Cracks in the Secondary Lining of a Tunnel Portal LI Fanghua, WANG Zhiyong 2016, 30 (2):  168-170.  Abstract ( 1211 )   Save Due to its softening and creep when the groundwater is encountered, the large deformation of tunnel in the soft rock mass is frequently occurred in the tunnel construction worldwide. This paper presents a case history of investigating the cracks in the secondary lining at the portal of Huangjiazhai Tunnel in Mazhu Expressway. The engineering characteristic of the soft rock mass, such as, type of surrounding rock mass, structure, strength and stress-strain property and the groundwater were evaluated. The probable factors that resulted in the cracking in the secondary lining were analyzed. Brocken, soft rock mass, groundwater sensitive and strong creep under stress are the major reasons. The mitigation scheme utilized the radial grouting from the perforated sleeve pipes for the entire cross section. Increasing the supporting and initial excavation and creating permanent drainage holes were also used in the mitigation system. Related Articles | Metrics

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Comprehensive Geotechnical Investigations for the Luneng Special Railway in Shanxi MA Shiju 2016, 30 (2):  171-173.  Abstract ( 1263 )   Save The Luneng special railway project in Shanxi crosses many geomorphological units, such as, alluvial terraces from the south to the north, rolling hills and middlelow mountainous area. Among these areas, the focus is the investigations of an excessive largespan bridge and a tunnel. Comprehensive geotechnical investigations were performed using geological survey, field investigation, test borings, test pits geophysics (high density electrical resistance method), insitu testing, field pumping tests as well as laboratory testing on soil, rock and water samples. The design parameters were therefore determined and the surrounding rock mass for the tunnel was able to be categorized. Related Articles | Metrics

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Deep Excavation under Complicated Geotechnical and Environmental Conditions WU Zhiping 2016, 30 (2):  174-178.  Abstract ( 1489 )   Save The deep excavation for the Suning Square is located in the north of Shanghai Bund. The proposed deep excavation has a very restrict environmental requirement and complicated geotechnical conditions due to its close approximate to the adjacent metro tunnel and historical buildings. Base on the specific requirements of the project, the metro tunnel and the historical buildings were closely monitored during the construction and these monitoring data were used to guide the exaction construction. The safety of the deep excavation and the adjacent structures were ensured during the construction   Related Articles | Metrics

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Data Fusion in Digital Processing and Interpretation for the Application of Shallow Seismic Exploration ZHOU Zhihua1, CHENG Jianjun2, ZHANG Jianzhi3 2016, 30 (2):  179-182.  Abstract ( 1231 )   Save In the shallow seismic geophysical investigation, the records of a single blasting contain information for the reflection and Raleigh waves. The fixed arrays of the receiving sensors are arranged in the field and the complete wave information can be collected. The surface Raleigh wave information can be obtained throughout the post process and the residual reflection calibration calculation can be performed using the data fitting method. Therefore, through one time data acquisition, both the surface Raleigh wave and the reflection wave information can be characterized and interpreted. Related Articles | Metrics

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Application of Shallow Seismic Method in the Evaluation of Tunnel Surrounding Rock Mass XIE Duoling 2016, 30 (2):  183-187.  Abstract ( 1394 )   Save This paper presents a case history of a geological exploration for an ore transportation tunnel for Jinduicheng molybdenum mining project. In the investigation, shallow seismic wave reflection method was used to delineate the bedrock depth, category of the surround rock mass and the location of the fault zone. In the practical project, it is necessary to use the optimized test borings to calibrate the geophysical results. Related Articles | Metrics

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Application of the Air-Foam Drilling in the Geotechnical Investigations YE Chong1, LIU Xinghua2 2016, 30 (2):  188-190.  Abstract ( 1151 )   Save This paper introduces the history, development, advantage, disadvantage and the state of the art applications of the airfoam drilling technique. The airfoam drilling is an attractive method in the draught or no water supply areas, slopes or areas near the retaining wall that are sensitive to the water seepage, areas with high environmental requirements and locations with high quality of soil samples. The quantity of the foam additives, control of air and the experience of the driller are critical to the success of the airfoam drilling. This paper introduces the application of the airfoam drilling method in a project in Hong Kong. Related Articles | Metrics

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A Modified Mononobe-Okabe's Seismic Active Earth Pressure Method QIU Mingce, WANG Shibin, KE Caitong 2016, 30 (2):  191-195.  Abstract ( 2598 )   Save The classic MononobeOkabe theory is widely used in the calculation of the seismic earth pressures, but its assumption of the earth pressure distribution and the action point of resultant force are inconsistent with the observed. This paper considers a wedged block with the top surface parallel to the backfill surface from the sliding wedge behind the wall. The analytical solution of the lateral earth pressure can be obtained from the moment equilibrium equations on the wedged block. The nonlinear lateral earth pressures distribution and the location of the point of action can be determined from the MononobeOkabe theory. In this formula, the lateral earth pressure magnitude changes with the rotation of the retaining wall. The formula was then verified with the model testing results and the results are consistent. The modified MononobeOkabe theory can reasonably predict the lateral under the static as well as seismic conditions. Related Articles | Metrics

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An Inversion Method Using PSO and GPR for the Rapid Determination of the Geotechnical Parameters HUANG Wei, LIU Hua 2016, 30 (2):  196-200.  Abstract ( 1312 )   Save To solve the problem of inaccuracy or missing information of the c and φ values for various soil strata in the geotechnical report for the shielded tunnel structures, a cooperative optimization algorithm based on the particle swarm optimization (PSO) algorithm and the Gaussian process regression(GPR) machine learning is presented. In the optimization process, the algorithm uses the approximation model of GPR to establish the relationship among the decision variables and the fitness functions. This relationship can be used as the approximate model of GPR as an evaluation tool of to resolve the time consuming problem in the engineering and can be the partial optimization during the global optimization process of PSO. This method was verified in the evaluation of the tunnel construction under cross the Ningtong Railway of the No 1 Line of Nanjing MetroRail Transportation Project. The results indicate that, compared with the basic PSO algorithm, the proposed method reduces the iteration numbers of finite difference for the back analysis and increase the efficiency.  Related Articles | Metrics

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NHRI Model Parameters Determination Using Triaxial Tests HOU Heying1, JIANG Minmin1, CAI Zhengyin1,2 2016, 30 (2):  201-204.  Abstract ( 1258 )   Save The NHRI constitutive model is one of the elasticplastic models, which utilizes the advantages of DuncanChang model and Cambridge model. The model has multiple yield surfaces and improves the disadvantage existed in the DuncanChang and the Cambridge model, in which they cannot simulate the stress path under a decreasing confining pressure. This paper presents the model determination of saturated silty soils by using the triaxial tests. Related Articles | Metrics

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Model Tests of Tunnel Excavation Pre-Support with Hollow Anchor Curtain SHENG Hao, GONG Jianwu, WANG Xin 2016, 30 (2):  205-208.  Abstract ( 1263 )   Save Model test is one of the effective tools to resolve the complicated geotechnical engineering problems. An analog theory in the model test is discussed in the paper in order to perform the physical model test for the application of hollow anchor curtain as the presupport in the tunnel excavation. The model test box design, model structure determination and the model test material composition and the test procedure and the data acquisition are evaluated and the key procedures in the tests are also introduced. This paper presents the technical details of the model test of using the hollow anchor curtain as the presupport in the tunnel excavation. The model testing items are summarized and the problems that need further study are also suggested. Related Articles | Metrics

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Loess Slope Stability Analysis Using Improved Orthogonal Method HOU Wencui1, XIN Quancai2 2016, 30 (2):  209-213.  Abstract ( 991 )   Save There are many factors that be influence the stability of soil slopes and these factors have different degrees of influence. This paper presents a case history of the stability evaluation of a loess soil slope in Kelan, Shanxi Province. The stability analysis is performed using the improved orthogonal method. This improved method is based on the conventional orthogonal design method and is combined with the grey correlation method. The analytical model was established with software ADINA and the model sensitivity to the parameters, such as, slope height, slope angle, unit weight, cohesion, internal friction angle and surcharge at the crest, are studied. The results indicate that, the strength parameters of the slope, slope ratio and the slope height have the significant impact on the safety of the slope. The surcharge and the unit weight of the soil has less impact. The appropriate slope stability design is then recommended: the reliable strength parameters should be selected in the design. The slope ratio and slope height should also be considered in the design. Related Articles | Metrics

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Measurement of the Cap Rock Sealing Capability to a Non-wetting Fluid with Front Displacement Work LV Guangzhong1, BAI Bing2, GUO Yingchun1, LI Zhipeng1, HU Qifang2 2016, 30 (2):  214-218.  Abstract ( 1071 )   Save The measurement of the cap rock sealing capability to the nonwetting fluids is one of the key tasks in the quantitative assessment of the cap rock. The existing measures cannot represent the sealing mechanism of cap rock thickness. A new method in terms of the Front Displacement Work (FDW) is developed to overcome this disadvantage. This measurement is the work that the fluid front pressure performs at the front displacement during the quasistatic displacement process, and therefore has a clear physical meaning. This measurement covers the two primary sealing mechanisms, i.e. the capillary sealing mechanism and the overpressure sealing mechanism. More importantly, it can reflect the sealing role of the cap rock thickness. Then, this measurement is compared with a newly presented methodology in the literature and applied to evaluate the cap rock sealing capability of Shasan segment of Dongying Depression. The results show that the Lijin depressing has the highest sealing capability and Niuzhuang depression has a lower sealing capability. The sealing capability is relatively low in the south slope area. The new measurement predicts the similar trend of sealing capability. This new measurement is very simple and it can simultaneously reflect the primary sealing mechanism. Related Articles | Metrics

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Finite Element Analysis on the Settlement of Levee Improved by the Blasting Replacement WANG Wei1, LI Yonghe2, WANG Jili3 2016, 30 (2):  219-222.  Abstract ( 1250 )   Save A sea levee over the thick mucky soft cohesive soils was improved by the blasting replacement method and both the short term and the long term settlement of the levee were analyzed using finite element method with laboratory test determined parameters. In the analysis, the riprap was modeled as the MohrCoulomb model and the soft soil was presented by modified Cam-Clay model. The riprap surcharge was placed on the improved soils and the settlement monitoring was performed in a 10 years after the completion of the levee. The monitoring and analysis results indicate that, after the riprap surcharge, the incremental stress in the soil increased significantly and the soft soil heaving were observed at both sides of the levee and the settlement was observed at the levee. The accumulative settlement after 621.2 days of the levee completion was 1.2 meters and the excessive pore water pressure was not dissipated completely. At time of 10 after the levee completion, the accumulative settlement was 1.55 meters. It is suggested that both the short term and long term settlements after the construction of the sea levee are significant, therefore, for the important sea levees, the control of the post construction settlement is very important. Related Articles | Metrics

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Industrial Building Deformation Predictions by BP Neural Network SHI Li, HUANG Tao  2016, 30 (2):  223-226.  Abstract ( 1178 )   Save The safety control, scheduled maintenance and monitoring of the industrial buildings under their normal operation are the very important tasks. This paper presents a case history of the comparison of the deformation data between the predicted and observed. The existing monitored data were used as the training samples for the neural network system. After the training, the deformations of the operational buildings could be predicted by the neural network. The deformation monitoring data on a 500tonne waste water treatment shop were used by the neural network and the future deformation of the shop was predicted. The results between the monitoring and predicted are consistent.   Related Articles | Metrics

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Incremental Stress Spreading in the Multi Soil Strata with Different Stiffness in Norther Anhui Soils LI Jinge1, YU Fei2， LI Jian2 2016, 30 (2):  227-231.  Abstract ( 1377 )   Save Small highway structures often distressed due to the insufficient bearing capacity in the foundations. The distressed structures might be a potential hazard for the safe operation of the highway. In northern Anhui, alternating of soil strata with significant different stiffness are widely deposited. The conventional bearing capacity evaluation method might not applicable to these stiffness alternating soil strata. This paper presents the evaluation results of the incremental stress spreading in the multi soil layers. The influence of the thickness of the target soils and the width of the foundation on the bearing capacity of the foundation is discussed. The fast and reliable evaluation of the foundation bearing capacity in the multi soil strata with stiffness alternations.\= Related Articles | Metrics

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Constitutive Model of Sandstone Discontinuities under Normal Loading and Unloading Conditions JIANG Li1, FAN Lei2 2016, 30 (2):  232-236.  Abstract ( 1082 )   Save A normal loading/unloading test were conducted out on the Silurian Luoreping Formation sandstone samples with discontinuities. The results indicate that, under the low normal stress conditions, the discontinuities deformation curves are in convex, and a concave shape is obtained on the discontinuities with the residual deformation under the normal unloading. The obvious stress strain hysteresis loops can be observed in the result. Currently, the normal deformation constitutive models of discontinuities are all empirical relations from laboratory test results. However, due to the difficulties in the determination of both the initial normal stiffness and maximum closure deformation at the discontinuities, the accuracy of these models is limited. A semilogarithmcircular arc constitutive model for predicting the normal deformation at the discontinuities is proposed in this paper based on the characteristics of low confining stress of the shallow rock mass. The loading curve is described by the semi-logarithm model and can be obtained from the regression analysis of the loading test results. The circular arc is used to represent the unloading process and it can be determined from the coordinates of three points: initial loading, final loading and the end of unloading. The calculated results were consistent with the laboratory test results. Related Articles | Metrics

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Variation of Strain with Spatial and Time in the Geogrid Reinforced Coarse Aggregate Soil Slopes XU Yebo 2016, 30 (2):  237-240.  Abstract ( 1204 )   Save Reinforced Soil Slope (RSS) is a widely used slope stability mitigation projects. The coarse aggregates are widely used as the backfill material due to their low cost, high compressive strength and high frictional resistance. The interactions between the geogrid and the coarse aggregates are not fully understood. This paper present a case history of the coarse aggregate filled RSS. The interface properties, the tensile strength of the geogrid in the RSS and the RSS failure modes are discussed. The factor of safety is obtained by using limit equilibrium method. The strain in the geogrid at different locations are monitored during the construction. Related Articles | Metrics

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Distributions and Mitigations of Expansive Soils in Wulian County, Shandong Province CHEN Ye1, WANG Lijun2, WANG Lixin3, YUAN Dalei1, LIU Dong2, XIA Lihua2 2016, 30 (2):  241-244.  Abstract ( 1328 )   Save The expansive soil is one of the problematic soils in the geotechnical engineering since it is a high plasticity soil and the volume will be contracted when the moisture in the soil is lost, whereas, when it absorbs the moisture, the volume of the expansive soil will increase. China is the largest country with the widest expansive soil distributions. There are 300 million populations who live within the expansive soil terrains and the expansive soil induced geohazards are frequently encountered. Under the natural moisture content state, the color of the expansive soils are usually gray black, yellowish brown or gray. Under this state, the compressive strength of the expansive soils are usually high. When they absorb water, their color turns into yellow, gray black with shinny luster. If a lowraised residential building is constructed on the expansive soils without treatment, the adverse consequence is most like to occur. This paper presents the distribution and evaluation results of expansive soils in Wulian County, Shandong Province.   \= Related Articles | Metrics

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Design and Implementation of an Automatic Monitoring and Alarming System for the Slope Stability LIAO Xiaoping 2016, 30 (2):  245-250.  Abstract ( 1120 )   Save This paper presents the design and implementation of an automatic monitoring and alarming system for the slope stability based on the fiber optical fault locating theory. The system components and their structures, functions, targets and software as well as hardware design and fabrications are introduced in the paper. The new device monitors the target slope with a systematically distributed monitoring points. It has the advantages of flexible monitoring points, low cost, easy to operate, reliable monitoring results and suitable for the remote monitoring. This device has also the advantage over the conventional monitoring device that can only monitoring several important local points and therefore is suitable for the higher grade roadway slopes with large monitoring points.\= Related Articles | Metrics

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Application of Three Dimensional Laser Scan in the Quarry Real Time Storage Monitoring XU Yinnian1, WANG Jiang2， YANG Lanqiang1 2016, 30 (2):  251-254.  Abstract ( 1477 )   Save The quarry storage requires frequent monitoring and measurements. The conventional method to conduct the storage survey is to use prism total station. However, due to the complicated topography and the survey error, this estimate might have significant technical difficulties. The three dimensional laser scan technique is able to avoid these shortcomings and provide a faster way of estimating the quarry storage. The paper also discusses the feasibility and the application of the new scan technique in the real time estimating the quarry storage. Related Articles | Metrics

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Shear Band Tests on the Remolded Guilin Red Clay HUANG Xiang, CHEN Xuejun, CHEN Long, XIAO Guiyuan 2016, 30 (2):  255-258.  Abstract ( 1187 )   Save This paper presents the shear band test results on the remolded red clay samples. Form the undrained triaxial test results, the shear failure modes were observed and the stressstrain characteristics were evaluated. The conditions that lead to the formation of the shear band in the sample were discussed and the inclination angle of the shear band was also measured and calculated. The results indicate that, under the undrained triaxial test conditions, the four different shear band shapes can be developed: single band, subsingle band, double bands with "T" shape and more than two parallel bands. There are significant different between the measured and predicted shear band inclination angles and the measured angle is generally greater than the predicted angle. The inclination angle predicted with MohrCoulomb theory is closer to the measured value. The heterogeneous soil property is the main factor leading to the development of the shear band, the loading magnitude and the boundary conditions are also the influence factors of the shear band formations. The inclination angle of the shear band is also influenced by the magnitude of the confining pressure and the dry density of the remolded sample. Related Articles | Metrics

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In-situ Moisture Content and Temperature Relationship Study in an Unsaturated Red Clay Slope GUO Jinglin 1, WEI Changfu 2,3, YAN Rongtao 2,3, HUANG Zhenyu 4， LU Youqian 2 2016, 30 (2):  259-264.  Abstract ( 1338 )   Save There are several theoretical models existed for describing the relationship between the moisture migration and the temperature in the unsaturated soils. However, most of them are developed based on specific assumptions and boundary conditions and none of them are verified with the data collected from the in-situ conditions in unsaturated red clay soil slopes. An insitu moisture migrationtemperature monitoring system was established at a red slope in Linyanshan, Guilin City.  This monitoring system not only real time monitored the moisture content and temperature change in the red clay slope, it also collected the site weather conditions, moisture content as well as the temperature in the unsaturated soils under the tropical and humid conditions. The monitoring results indicate that, the moisture content and the temperature in the red clay slope changes with ambient weather conditions. The moisture content and temperature in the shallow depth vary significantly with the ambient weather. Under the precipitation conditions, the ambient temperature decreases, the moisture content in soil increases and temperature decreases and vice versa. The moisture content in soil has connected with the temperature in the soil. The increase of the moisture content reduces the influence depth of the ambient temperature and the range of the soil temperature change. With the increase of the depth, the ambient temperature has less influence on the moisture content and temperature variations. Related Articles | Metrics

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Engineering Properties and Plate Loading Tests on the Granitic Residual Soils in South Jiangxi FAN Youjie 2016, 30 (2):  265-268.  Abstract ( 1296 )   Save The granitic residual soil is one of the special soils that are widely deposited in China. The characteristics of the granitic residual soil are: highly structured and having high strength when its fabric remaining undisturbed; having medium to low compressibility; high moisture content and high void ratio; low compression modulus and low liquid index. The engineering properties of the granitic residual soil are different from those of conventional cohesive soils and the bearing capacity estimation method used in conventional cohesive soils cannot be utilized in the granitic soils. This paper presents the evaluation results of the engineering properties of the granitic soils and the bearing capacity test results. Related Articles | Metrics

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Experimental Study of the Strength of the Unsaturated Granitic Residual Soils DENG Shudong. ZHU Fangcai, LI Dajian 2016, 30 (2):  269-273.  Abstract ( 1121 )   Save This paper studies the strength characteristics of the Hengyang unsaturated granitic residual soils. The soil water characteristic curves of the granitic residual soils were determined by the filter paper method and the consolidated undrained shear tests were performed to analyze the influence of the initial matrix suction and the water content on the strength of the soil. The results indicate that, within the range of tested moisture, the suction of the unsaturated granitic residual soil decreases with the increase of the moisture content, but the moisture content is less affected by the initial matrix suction. Correspondingly, the internal friction angle decreases linearly with the increase of the moisture content and the cohesion changes in a quadratic relationship. The change of the initial matrix suction in relation with the internal friction angle and cohesive is nonlinear. Related Articles | Metrics

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Experimental Study on the Shear Behavior of the U-section Thin-walled Steel-Concrete Composite Beams ZHAO Qinglong1, WANG Wei1, SHEN Jianhua2 2016, 30 (2):  274-280.  Abstract ( 1129 )   Save Comparative studies were performed to analyze the mechanical properties, flexural failure modes, distribution of the load-displacement and cross sectional stress of the mid-span as well as the changes of the shear stress-strain of the composite beams. A total of eight (8) U-section thin-walled steel-concrete composite beams were tested for the shear resistance behavior. The results indicates that, compared with the steel beams and the other concretesteel composite beams, a better ductility can be found in the U-section thin-walled steel-concrete composite beams under the shear failure mode. Since it is filled with the concrete in the web, the beam web's buckling mode changes from the three half-buckling wave to one half-buckling wave, the load carrying capacity of the composite bean was improved significantly compared with the steel beam. The flexural failure of the U-section thin-walled steel-concrete composite beam occurred when the shear span ratio is less than 2. At the flexure failure, the shear span ratio of U-section composite beam is less than that of the conventional steel-concrete composite beam. Related Articles | Metrics