Table of Content

20 August 2014, Volume 28 Issue 4 Previous Issue    Next Issue

For Selected:

Download Citations EndNote Reference Manager ProCite BibTeX RefWorks

Toggle Thumbnails

Select

Optimization Design of a Gravity Retaining Wall over Soft Soils WU Shun1, YANG Jibao2, CHEN Zhibo2, ZHANG Huixin2 2014, 28 (4):  1-4.  Abstract ( 1610 )   Save A soilcement mixed gravity retaining wall was used as the deep excavation supporting structure in Wuhu, Anhui Province. The project site consists of large thickness of peaty soil soils. Factors that affecting the stability of the gravity retaining walls are evaluated and the optimized dimensions of the gravity retaining wall supporting structure are obtained. It is observed that the gravity retaining wall supporting structure requires a minimum thickness as well as a minimum embedment depth. Related Articles | Metrics

Select

Application of TRD method in a Deep Excavation for Yangtze River Navigation Administration Center XU Guoxing1, TAO Zhibin2 2014, 28 (4):  5-7.  Abstract ( 1970 )   Save The Yangtze River Navigation Administration Center Project is located at the intersection of Yuanjiang Boulevard and Minsheng Road in Jiangan District. The proposed building has a total area of 46,000 m2 with a building area of 31,500 m2. The foundation excavation area is 38,600 m2, with a perimeter f 888 meters. The proposed excavation depth varies from 10.7 to 21.9 meters and this type of deep excavation can be classified as superlarge excavation project. Based on the hydrological and geological conditions at site, the conventional castinplace reinforced concrete pile with threeaxis cement mixing curtain as a seepage cutoff wall was used as supporting system in areas with twostory underground spaces. In areas with threestory underground spaces, the hydraulic pressure is high due to the required excavation depth. The slurry walls formed by the Trench Cutting Remixing Deep Wall (TRD method was used. The TRD walls can have a large structural depth and is applicable in a wide variety of subsurface conditions. The cross strut supports with corner supports using truss system in the horizontal direction are used in both areas. Related Articles | Metrics

Select

Rehabilitation of Tilted Manholes in Soft Soils FAN Xinfa1， LUO Hongbing2， FAN Cong3 2014, 28 (4):  8-10.  Abstract ( 1861 )   Save Jianghan plain area consists of soft soils. Many manholes for the stormwater and waste water frequently have tilting problems due to various causes, such as, bad design and geotechnical investigation, poor construction and poor inspection processes. This paper presents the case histories of tilted manholes in soft soil strata. The causes of the tilted manholes and it rehabilitation process are also introduced in the paper. Related Articles | Metrics

Select

Comparative Analysis of Settlement in Craters by Dynamic Compaction with Different Filling Materials TANG Dongmei1, BAO Yanjun2 2014, 28 (4):  11-13.  Abstract ( 1689 )   Save This paper presents the dynamic compaction soil improvement mechanism and a case history of a dynamic compaction project.The settlement values with different filling materials under each tapping are comparatively studied at the pilot test area. Related Articles | Metrics

Select

Surcharge and Preloading Duration of a Railway Embankment over Coastal Soft Soils ZHOU Xiaoxi 2014, 28 (4):  14-18.  Abstract ( 1643 )   Save Settlement magnitude and surcharge duration estimations are the main research aspects of the preloading of railroad embankments over soft soils. A railway embankment over the coastal soft soil beach is improved by surcharging with Prefabricated Vertical Drains (PVD). A geotechnical instrumentation program including surface settlement plates, piezometers and extensometers is also implemented during the construction. The subsurface soft soil settlement and pore water pressure characteristics are summarized from the observed data. The hyperbolic curve fitting method was used in predicting the post construction settlement as well as the degree of consolidation of the soft soils. The relationship between the surcharging loading duration and the post construction settlement as well as the degree of consolidation was established. The results indicate that the surcharging with PVD method effectively improves the coastal soft soils. The surcharging duration can be estimated in accordance with the surface and sublayer settlement magnitudes, pore water pressures, post construction settlement as well as the degree of consolidation of soft soils. Related Articles | Metrics

Select

Foundation Optimization Design and Bearing Stratum Selection fora Business Reception Center HUANG Zhenhui1, WANG Zhipeng2 2014, 28 (4):  19-21.  Abstract ( 1354 )   Save This paper presents a case of the geotechnical investigation and analysis for a business reception center facility. Both field investigation and laboratory test results are analyzed. The optimized foundation type and its bearing stratum are determined. The selected foundation has the characteristics of cost effective and construction efficient. Related Articles | Metrics

Select

Analysis of Pile Foundations in a Large Rehabilitation and Expansion Project GUO Hongmei 2014, 28 (4):  22-26.  Abstract ( 1685 )   Save Structures in a rehabilitation and expansion project are pile supported and have a very strict total and differential settlement requirement on the foundations. The structures have large dimension and are not uniformly loaded. It is concluded that the post grout below the pile tips and at pile sides can improvement axial capacity and the stiffness of the castinplace reinforced concrete piles. The total and differential settlement reductions are achieved by the analysis the interactions among the supper structures, foundation soil and piles, and by using variable rigidity adjustment design. The pile foundation design is also optimized. Related Articles | Metrics

Select

Application of Rigid Column Composite Foundations for a Cement Storage Facility in Karst Areas LIU Minghua 2014, 28 (4):  27-29.  Abstract ( 1220 )   Save The paper presents a case history of using rigid column composite soil as a soil improvement method for the foundation construction of a cement storage facility in karst terrain. The results indicate that this method is technically reliable and cost effective method. Related Articles | Metrics

Select

A Seepage Cutoff of Red Mud Storage Yard in Karst Terrain MA Ning, SONG Xu 2014, 28 (4):  30-32.  Abstract ( 1650 )   Save A red mud storage yard of China Aluminum Guizhou Co. is located in a karst terrain. The alkali solution from the red mud requires seepage cutoff design to prevent leakage to the karst rock fissures. This design is the first jet grout case history reported by using conventional portland cement slurry in the karst environment for the seepage cutoff design for strong alkali solutions. Related Articles | Metrics

Select

Zhunyi Karst Terrain Sinkhole Collapse Evaluation and Hazard Predictions LIU Baochen1, TANG Qian1, QIU Mengyao2 2014, 28 (4):  33-36.  Abstract ( 1131 )   Save Karst sinkhole hazards have the characteristics of wide distributions, frequent occurrences, hard to predict, many affecting factors; high variation and complication as well as high cost for the remediation after collapse. This paper evaluates aspects that cause the karst sinkholes and possible major factors that affecting the collapse are determined in order to provide predictions for the sinkhole risk potentials. The evaluation method utilizes the theory of analytic hierarchy process so that the risk potentials can be reliably evaluated in both quantitatively and qualitatively.  The five (5) subsidence factors, karst conditions, hydrological conditions, topographical conditions, cover thickness as well as human activities, are analyzed using hierarchy process. Their contribution to the collapse are weighted and programmed in excel spreadsheet. The regional subsidence potential is then provided. Related Articles | Metrics

Select

Engineering Properties and Mitigation Methods of Expansive Soil in Munga, Sudan TANG Shenggui, TANG Guanghui 2014, 28 (4):  37-40.  Abstract ( 1697 )   Save Expansive soils are mainly composed of highly hydrophilic clay minerals such as montmorillonites and illites.  They have typical characterizations of expansive soils: high plasticity clay with typical expansive structures, fissures, strong swellcontraction and strength reduction with increase of moisture content. This paper presents the case history of the geotechnical investigation for a power transmission line project in Munga, Sudan. The engineering properties of the expansive soils in the region are evaluated and the methods for mitigating the hazards induced by the expansive soils are compared. The empirical correlations among the expansive soil properties and plastic index as well as liquid limits are established. The paper also evaluates the correlation between the expansion force and the initial moisture content. These results can provide guide lines for the foundation constructions in Munga region as well as the research of expansive soils in China. Related Articles | Metrics

Select

Mechanical characteristics of the bedded rock salt from Jintan Salt Mine HUANG Mengyun1, LIU Wei2 2014, 28 (4):  41-43.  Abstract ( 1099 )   Save Energy storage caverns in salt formations of a Jintan salt mine are proposed. The mechanical properties are fundamental aspects of cavern design, stability evaluation. The laminar salt rock samples are systematically studied throughout uniaxial, triaxial, direct shear and split tests. The test results indicate: the Jintan salt rock samples are soft rock mass. The split failure is the major failure mode under the uniaxial compression tests. The shear strength as well as the plasticity under triaxial shear tests is increased. The lenses of other rock type in the salt rock increase the strength of the salt rock and therefore improve the stability of the rock cavern. The interface between the salt rock and other rock type is not a weak zone and its strength is similar to that of salt rock. The strong interface strength is beneficial to the gas storage cavern and its airtight properties. Related Articles | Metrics

Select

Construction of a Long Water Diversion Tunnel under High Geo-thermal Temperature Conditions ZANG Hongmin1, LI Shuchen2, MA Tengfei2, ZHANG Luchen2, WANG Shulei3 2014, 28 (4):  44-47.  Abstract ( 1847 )   Save The excessively high geothermal temperature in a water diversion tunnel of Niangyong Hydraulic Electricity Generation Station resulted in serious construction difficulties: the surface temperature of rock mass after the blasting reached 75 degrees Celsius; the highest water rushed in the tunnel was 82 degrees Celsius; the ambient temperature in the tunnel was 53 degrees Celsius. A temperature reduction system through the ventilation was established and the temperature in the tunnel was able to be reached to 30 degrees Celsius. A safe and comfortable tunnel excavation condition could be developed under the excessively high geothermal conditions. Related Articles | Metrics

Select

Construction Technique of a Large Section Underpass underneath a Railway YANG Limin, LIU Congyun 2014, 28 (4):  48-50.  Abstract ( 1307 )   Save This paper presents a case history of the construction procedures of a large cross section underpass underneath a railway at Jingguan Boulevard North in Xiaoyi City. The selection of construction procedures in the large cross section underpass, launching and receiving of horizontal tunneling techniques as well as the mechanics of horizontal tunneling are introduced in the paper. The selection of tunneling segment length and other parameters are also presented. The construction results indicate that the launching and receiving method has the advantage of working a limited space. This method provides a solution to the construction of underpass with horizontal tunneling in long distance under limited space. Related Articles | Metrics

Select

Monitoring and Evaluation of Deformation and Stress inSupporting Structures of Tianjingshan Tunnel ZHAO Canyuan, ZHAO Dongqi 2014, 28 (4):  51-53.  Abstract ( 1939 )   Save This paper presents the monitoring results of tunnel deformation, stress in supporting structures and rock mass displacement during the construction of Tianjingshan Tunnel. The surrounding rock mass can be classified as IV or V grades, which are the broken rock masses. The tunnel stability was evaluated and predicted based on the monitoring results. The supporting parameters were adjusted based on the tunnel stability evaluation. The results indicate that, the construction monitoring, analyses and information feedback have significant importance for highway tunnels under complicated geological conditions. It has also signification importance for the cost saving and safety assurance. Related Articles | Metrics

Select

Safety Evaluation of the Existing Buildings over the Grouting of a Shallow Excavated Tunnel ZHANG Deyong, FANG Haoliang, HAN Bingbing 2014, 28 (4):  54-56.  Abstract ( 1755 )   Save This paper present a case history of the stability evaluation of an existing building. This building is over a shallow excavated tunnel and the grouting on the tunnel is required. The evaluation combined with both insitu monitoring and the numerical analysis approach. The grouting operation on an entire cross section is simulated with FLAC 3D software. The deformation of the ground soil mass and the stress on the supporting structures are analyzed. Related Articles | Metrics

Select

Analysis of the Stability of a Slurry Wall for a Subway Station DU Jiangtao 2014, 28 (4):  57-59.  Abstract ( 1464 )   Save This paper evaluates the conventional methods for the stability of the slurry walls and the major factors that affect the slurry stability in the construction and operation. The slurry stability of a subway station in Nanjing Metro System was analyzed as a case history. The analytical results are compared with the observed results. Related Articles | Metrics

Select

Factors Affecting the Axial Capacity of Soil Cement Mixed ColumnInserted with the PHC Pile ZHANG Yonggang1,2 2014, 28 (4):  60-65.  Abstract ( 1747 )   Save A new composite pile consists of a Prestressed Highstrength Concrete (HPC) pipe pile inserts into a fresh soilcement mixed column before it is hardened. This new composite pile can be applied for the soil soft improvement projects. The paper presents the numerical analysis results by using ABAQUS software as well as the static loading test results. The numerical analysis studies the influence of various factors on the axial resistance of the composite pile. These factors include: the length of PHC pile; ratio of pile diameter to the tributary diameter of the composite pile; diameter of the soil cement mixed column and its stiffness; etc. The optimized PHC pile and the soil cement mixed column relationship are obtained. The analysis results indicate that the key factors that are impacting the axial resistance of the composite pile are the length of PHC pile and the ratio of pile diameter to the tributary diameter of the composite pile. The impact of the stiffness of the soil cement mixed column on the axial resistance of the composite pile is relatively small. The ratio of the PHC pile and to the soil cement mixed column should be between 3∶5 and 4∶5. The ratio of the PHC pile to the tributary diameter of the composite pile should be ranging from 0.19 to 0.25. The minimum diameter of the soil cement mixed column should be 300 mm greater than that of the PHC pile. Related Articles | Metrics

Select

Design and Connection Details of a Grid Diaphragm Wall YANG Bo1, SUN Bangbin2, GUO Tong1,3, SONG Yongsheng1,3, WEI Longwu1, YAO Bing2 2014, 28 (4):  66-69.  Abstract ( 2315 )   Save The grid diaphragm wall is constructed by continuously sinking the steel forms into the soil, placing the reinforcement bars and concreting the grid. This new type of wall can serve as the supporting structure during the deep excavation and also as the exterior wall of the future basement. The grid diaphragm wall combines the functions of both supporting and the structural walls. This paper presents the evaluation results of this wall in various phases: during the supporting in deep excavation, immediately after construction and operation. The stress distributions in the wall at various stages are analyzed. The connection joint and seepage cutoff details are also presented. The results show that the active earth pressures during the construction was translated into atrest earth pressure in the operation and the groundwater is restored to the static water table. The moment connectors welding connections can be used at connections between wall and floor (bottom slab), wall and beam so that the reliability of these connections can be improved. For the body of the diaphragm wall, wall and beam connections, wall and bottom slab joints, seepage resistant concrete, shear stiffeners and seepage cutoff steel plates can be applied in combination with seepage prevent materials of paint. Other seepage cutoff measures such as, expansive rubber seepage stop strips and water based epoxy grouting, can also be applied. The above results can provide technical references for the future design and construction of the grid diaphragm walls. Related Articles | Metrics

Select

Refined Analysis on the Deep Excavations WANG Kan1, LI Zhi2 2014, 28 (4):  70-72.  Abstract ( 1153 )   Save This paper presents the refined numerical modeling results of the deep excavation process by considering the special stressstrain relationship of the soil mass, dewatering boundary conditions as well as the soilpile interactions. The Hardened Soil (HS) model is used in simulating the unloading conditions; the impact of dewatering on the ground subsidence. The Goodman type interface elements are applied at the contact areas between soil and soldier piles to simulate the sliding displacement between the pile and soil. Five conditions are analyzed and compared with the observed results in the case history. The analyzed results are consistent with the observed data. Related Articles | Metrics

Select

Numerical Analysis of the Effects of Multiple Deep Excavations on the Existing Metro Tunnels CHEN Hong, CHU Zhenhuan, ZENG Qingguo 2014, 28 (4):  73-77.  Abstract ( 1191 )   Save This paper presents the results of three dimensional finite element analysis model using MIDASGTS commercial software. The effect of multiple deep excavations on the existing metro tunnel is numerically simulated. During the foundation excavation, the numerical results are verified simultaneously with the instrumented values that made in the tunnel. The subsequent foundation excavation on the metro tunnels can therefore be predicted and the design and construction can be optimized. This approach provides a safe guard for the foundation excavation construction and the operation of the subways. Related Articles | Metrics

Select

Comparative FEM Studies on Embankment Settlement Using Elastic and Elasto-Plastic Theories LIU Xinghua1,2, YE Chong3, LI Xuchong1,2 2014, 28 (4):  78-81.  Abstract ( 1653 )   Save The instant settlement, pore pressure as well as the consolidation settlement of an assumed embankment over cohesive soils is numerically analyzed by using finite element method (FEM) with both elastic and elastoplastic theories. The results indicate that, the zone of loading influence using elastic theory is significantly greater than the results using elastoplastic theory. The elastoplastic analysis should be used in embankments over the normally to slightly over consolidated soils. For embankment or atgrade roadway on heavily overconsolidated soils, elastic theory might be used. It is also concluded that the boundary conditions have strong influence on the analytical results. Related Articles | Metrics

Select

The Failure Modes and Stability Analysis of Complicated Rock Slopes ZHAO Yao, WANG Hao, GONG Kuangzhou， LIN Zhen 2014, 28 (4):  82-85.  Abstract ( 1713 )   Save In the southeast Fujian Province, the rockfall induced by the spherical weathering of granite rock mass is one of the most prominent geohazards. One of the methods to minimize the rockfall hazard is to study the rockfall movement and to determine the optimized slope shape. This paper presents the rockfall trajectory study results of three basic variables: slope angles; width of relief platforms and slope shapes. The main conclusions are: compared with rock slopes, soil slopes with vegetation cover have an obvious "energy dissipation" effect; increase the width of the relief platform and install vegetation on the relief platform will effectively impede the movement of rockfall. Flatten the slope will delay the initiation of the rock rolling and will control the distance of the rock movement. A wide relief platform with a flat upper slope, a steep lower slope is the optimized configuration for the rockfall hazard control. Related Articles | Metrics

Select

Developments of Slope-Tunnel Interactions LUO Jianhang， ZHU Kuzhu 2014, 28 (4):  86-89.  Abstract ( 1619 )   Save The developments of the slopetunnel interaction, especially, the geohazards in tunnels near slopes, are reviewed in this paper. The landslide, landslide induced geohazards in Xiaomansa River tunnel and classifications of deformations in the tunnel are studied. The landslide induced geohazards and relationships between deformation and geology are investigated. The field reconnaissance of the tunnel after the landslide as well as the mechanism in landslide and tunnel interaction is also presented. This paper also reviews the developments of the model and analytical studies of the tunnels near landslides. Related Articles | Metrics

Select

Remediation on Jammed TBM in Daban Diversion Tunnel Excavation LU Chengbo1， XIN Fengmao2， CAO Yang2， ZHANG Yuelin2 2014, 28 (4):  90-92.  Abstract ( 1438 )   Save The Daban diversion tunnel has a total length of 31.92km. This tunnel crosses many poor geological areas, such as, expansive rock mass, clayey silty fine sandstone rock masses. The Tunnel Boring Machines (TBM) was jammed and successfully remediated several times during the tunnel excavation. This paper summarizes various grouting methods that are applied in the tunnel excavation, such as, gravity grout, compaction grout and seepage cutoff grout. Related Articles | Metrics

Select

Support Stress Prediction and Liner Selection in the Excavation ofDaban Diversion Tunnel ZHU Liping1, MA Pin1, ZHANG Lei1， ZHANG Yuelin2 2014, 28 (4):  93-94.  Abstract ( 2075 )   Save This paper presents a comprehensive review of the applications and limitations of using Protodyakonov and Terzaghi theories in the different surrounding rock mass types in Daban Diversion Water Tunnel Project. For the excavation in hard rock mass segments, the supporting stresses are determined through the insitu geostress measurement and numerical back analysis using finite element methods. The stresses in the liners can also be estimated and the appropriate liner type can be selected. The construction results indicate that this approach is reasonable. Related Articles | Metrics

Select

Selection of TBM for DABAN Diversion Tunnel XI Zhuhui1, SUI Shijun2, MA Pin1， ZHANG Yuelin2 2014, 28 (4):  95-98.  Abstract ( 1676 )   Save This paper presents the Tunnel Boring Machine (TBM) selection results for the excavation of Daban long distance diversion tunnel. The double shielded TBM was selected for the specific site conditions: highly stressed soft rock mass, high external ground water pressures and expansive rock mass. The special construction techniques such as the remediation of sudden water, mud and sand rush into the tunnel, are also presented. The research results indicate that the TBM type selection is critical to the success of the long distance tunnels excavation. In addition to the cost, efficiency, and safety requirements, the site geological conditions should also be considered for the TBM type selection. Related Articles | Metrics

Select

Discussion on the Modified CSMR Method in the Rock Slide Stability Evaluations LIU Faxiang, YANG Chaofa 2014, 28 (4):  99-103.  Abstract ( 1846 )   Save This paper evaluates the recent developments in generalized Continuous Slope Mass Rating (CSMR) research. A modified CSMR method that considering the disturbance effects on the rock slides was proposed. This modified CSMR method has a better characterization of the geological conditions in rock slides. A typical rock slide site is evaluated with this modified CSMR method as a case history and the results are compared with the geotechnical investigation results. In the evaluation, relationships between the Stability Coefficient, Ks, and CSMR are applied. These results indicate that the modified method is appropriate in the rock slide evaluations. Related Articles | Metrics

Select

A Seepage-Stress Coupling Model of Tailing Columns under the Chemical Action ZHENG Xunzhen 2014, 28 (4):  104-105.  Abstract ( 1493 )   Save This paper presents the research results of a seepagestress coupling model for the elastic modulus of tailing columns under the action of chemical fluids. Based on the previous research results by others, the effect of change of pH properties of the chemical solutions with time on the elastic modulus of tailing columns is numerically analyzed. Related Articles | Metrics

Select

Analysis of the Stability and Dynamic Properties of Tailings Slopesunder HighSpeed Train Vibrations XU Xutang1,2， JIAN Wenbin1,2 2014, 28 (4):  106-110.  Abstract ( 999 )   Save The stability of the tailing slopes under highspeed train induced vibrations is directly related to the train operation safety. This paper presents a case history of the stability of a tailing slope in Fujian. The development of dynamic shear modulus ratio (G/Gmax) and the change of the dynamic damping ratio (λ) with the dynamic shear strain (γ) under different confining pressures are obtained through the characterization of the dynamic parameters of the tailing silt other tiling soil samples with the dynamic triaxial shear tests and resonant column tests. Based on the measured vibration and the acceleration characterization of the highspeed trains, the stability and liquefaction of the tailing slopes are evaluated. The results indicate that the stability is not a concern and the liquefaction und the vibration is not likely. Related Articles | Metrics

Select

Quality Control Aspects of Geotechnical Investigations QUAN Xiaohong， MEI Bao 2014, 28 (4):  111-113.  Abstract ( 1881 )   Save It is important to standardize the quality assurance and quality control of the geotechnical investigation in order to maintain a consistent level of the engineering investigation results. Key aspects of the quality control in the geotechnical investigation are discussed in this paper. Related Articles | Metrics

Select

An Innovative Geothermal System in Guiyang LI Chaojia, LI Yonggang， HE Wenjun 2014, 28 (4):  114-116.  Abstract ( 822 )   Save Although the late start of the geothermal pump technology in China, it has a rapid development in recent years. The geothermal pump has a wide application in hot air and water supplies and air conditioning areas. This paper briefly discusses the principles of the geothermal pump technology and then presents a case history of geothermal application.  The proposed site has a relatively small footprint but a single vertical U pipe could not meet the supply requirement for the building.  A new double vertical U pipe heat exchange system in combining the spiral coil heat exchange system of the foundation piles was developed for the project. The results are satisfactory. Related Articles | Metrics

Select

Application of EPC and PMC in the Nuclear Power Engineering Projects ZHAO Xiang 2014, 28 (4):  117-119.  Abstract ( 909 )   Save This paper introduces the basic concepts of two different contracting methods: Engineering Procurement Construction (EPC) and Project Management Construction (PMC). Their applications in the nuclear power engineering construction projects are introduced through two typical case histories. This paper also presents the suggestions of the development of PMC in the nuclear power engineering construction industry in China. Related Articles | Metrics

Select

Basic Physical and Mechanical Properties of Red Mud from an Aluminum Plant ZAN Jinmao， MAO Jiuping 2014, 28 (4):  120-123.  Abstract ( 1217 )   Save A total of 354 samples of fresh filtered, natural consolidated and compacted red mud cakes are tested for moisture, unit weight, specific gravity, dry density, void ratio, degree of saturation, permeability, grain size distribution, consolidation, consolidated and undrained shear test and triaxial shear test. The test results indicate that the freshly filtered red mud cakes have the geotechnical properties similar to that of silty soils. It has the characteristics of high moisture contents, high degree of saturation, high void ratio and low shear strength. The red mud samples are wellgraded. The optimum moisture content under the Proctor test is 41.6% with a maximum dry density of 1.25g/cm3. The shear strength of the red mud samples prepared under the optimum moisture content has a significant increase. An increase of shear strength of red mud samples with time of storage is also observed. These findings provide references for the red mud of aluminum plant storage and the design and construction red mud storage dams. Related Articles | Metrics

Select

Comprehensive Testing on Modified Expansive Soils as EmbankmentMaterials in HefeiNanjing Railway ZHOU Ge 2014, 28 (4):  124-128.  Abstract ( 1581 )   Save The experimental studies and railway operations observations of the use of modified expansive soils as embankment backfill materials in Hefei Nanning Railway project are presented in this paper. The feasibility of modified expansive soils as railway embankment backfills are studied through laboratory limesoil mixing ratio, field backfill trial test, quality assurance test and dynamic measurement and deformation observations. The embankment with modified expansive soils was minored throughout four years of operation. The results indicate that the embankment with modified materials is successfully constructed. The expansive soil modification design, embankment construction procedure and its quality assurance standard are also proposed in the paper. Related Articles | Metrics

Select

Feasibility of Using SDW-100 Displacement Transducer to Measure the Deformation of High Strength Geotextiles KONG Jing 2014, 28 (4):  129-131.  Abstract ( 1625 )   Save The high rigidity SDW100 displacement transducers are used in measuring the deformation of a geotextile with a tensile strength of 500kN/m in laboratory and field conditions. The test results indicate that it is feasible to use this type of transducer in the deformation measurement of high strength geotextiles under field conditions. Related Articles | Metrics

Select

True Triaxial Undrained Shear Tests of a Clay Sample HU Shuzhi1, YANG Xueqiang1, ZHANG Xintao2 2014, 28 (4):  132-134.  Abstract ( 1034 )   Save A series of true triaxial shear tests of Guangzhou structured natural silty clayey samples are tested with consolidated undrained shear with an equivalent stress ratio. A new parameter, called equivalent strain ratio, b , is introduced in this paper, in order to characterize the mechanical properties of this structured silty clayey samples under similar conditions. Related Articles | Metrics

Select

Analysis of the Differences in Moisture Contents Tested with Different Methods YUAN Fei1,2, ZHOU Hong3, LI Bin4, YANG Shuguang1 2014, 28 (4):  135-137.  Abstract ( 982 )   Save The moisture content is an important property of soils and is an index of mechanical property. The moisture content can be determined by various different methods. Of many testing methods, this paper presents the comparative test results on the moisture contents of red clay samples from QinghaiTibet with oven dry as well as microwave dry methods. The test results indicate that the moisture contents tested by oven dry and microwave dry are similar. The plastic indices obtained by both methods are also similar. For the QinghaiTibet red clay, the moisture contents by oven and microwave method can be substituted. Related Articles | Metrics

Select

Laboratory Experimental Testing of Cement Modified NanyangMedium Expansive Soils CEN Sheng1, WANG Xiequn2, JIAO Qiuxia3, FAN Huawei4 2014, 28 (4):  138-141.  Abstract ( 1284 )   Save A cement modified Nanyang medium expansive soil with a free expansion ratio of 77% is extensively studied in the laboratory conditions under a degree of compaction of 98%. The expansive properties of modified and unmodified expansive soil samples, such as, free expansion ratio, shrinkswelling indices, Atterberg Limits, grain size distribution and unconfined compressive strength, are tested with different cement ratios and curing ages. The following conclusions can be drawn: 1) with the increase of cement content, the liquid limit and plastic index, which are the indices of shrinkageswell and plasticity of modified expansive soils, are reduced. The clay content in soil samples is also reduced. A flat gradation curve is observed. The unconfined compressive strength and elastic modulus are increased. The optimum cement ratio is tested to be 6%. 2) with the increase of curing time, the shrinkageswelling indices, liquid limit, plasticity index and clay content are reduced and the unconfined compressive strength as well as elastic modulus are increased. Related Articles | Metrics

Select

Control of Delayed Enttringite Formation in the Mass Concrete inTaishan Nuclear Power Plant QIAO Shi, ZHANG Jian, ZHENG Zhongfeng 2014, 28 (4):  142-146.  Abstract ( 1757 )   Save The proper evaluation of the delayed enttringite formation (DEF) in the mass concrete is an important index of the duration of mass concrete in the nuclear power plant construction. In order to control or minimize the delayed DEF in the mass concrete, the mix design of the specific concrete is evaluated. The preliminary test simulations are performed to find the technical measures that minimizing the DEF. Under any condition, the highest temperature in the center of the mass concrete should not exceed 80 degrees celsus. Related Articles | Metrics