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    30 April 2018, Volume 32 Issue 2 Previous Issue    Next Issue
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    Application of SMW Method in Deep Excavation Supporting in Soft Soils
    WU Fa-Gen-1 , HUANG Luo-Hua-2, XIONG Hai-Ming-1
    2018, 32 (2):  111-115. 
    Abstract ( 708 )   Save
    This paper presents a case history of applying the soil mixing wall (SMW) method in the deep excavation supporting in the soil soils. The frequently countered problem and solutions in the excavation supported are discussed. One of the advantage of the SMW method over the other supporting methods is that the hot rolled steel beams can be reused after the supporting completion and the costing saving could be as much as 40%. Compared with the castinplace concrete soldier pile method, the SMW method has the advantage of simpler construction procedure, faster construction schedule and less disturbance to the adjacent environment.It is concluded that the SMW method has the advantage over other conventional supporting methods in the deep excavation supporting in soft soils.
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    Application of High Pressure Jet Grouted Anchor in a Super Large Deep Excavation in Soft Soils
    LI Hong-Ran
    2018, 32 (2):  116-118. 
    Abstract ( 799 )   Save
    In recent years, high pressure jet grouting anchor support technology receives more applications in the deep excavation engineering in soft soils. This method, comparing with the with the traditional grouting ground anchor, has the advantage of higher axial capacity due to the improved grouted portion. However, the application in super lager foundation excavation in soft soils with a supporting depth of more than 15 meters is still rarely reported. This paper presents a case history of applying this method in a very large deep excavation system near Taihu Lake, Suzhou City.  The subsurface soil conditions at the project site have the characteristics of thick muck layer, highly compressible, and highly sensitive. During the jet grouted anchor installation, the inclination angle and length of the anchor were slightly adjusted and retension technique was used. The results were successful.
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    Application of the Composite Foundation with Sparsely Spaced Columns in the Building Differential Settlement Corrections
    ZHU Si-Xiang-1 , WEI Xiao-Jing-2
    2018, 32 (2):  119-121. 
    Abstract ( 655 )   Save
    This paper introduces the basic theory and stress mechanism of the composite foundation with sparsely spaced columns and the application of this method in the correction of a building suffering from the differential settlement. The factors that cause the inclination of the building evaluated and the differential settlement mitigation plan is presented. From the analysis of the axial resistance compressive columns, it is concluded that this method is reliable in the differential settlement mitidations.
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    Deep Excavation Supported by a Combination of Gravity Retaining Wall, Soil Nail Wall and Pile strut
    QIU Xiao-Ming
    2018, 32 (2):  122-125. 
    Abstract ( 796 )   Save
    A case history of the deep excavation in soft soils supported by the combination of gravity retaining wall, soil nail wall and pilestrut is presented in this paper. The paper compares the feasibility, advantages and disadvantages of this combination method with the application of one of the three methods alone in the deep excavation. The construction monitoring data indicated that this method can be successfully used in the deep excavation project in soft soils with an excavation depth between 7 and 10 meters.
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    Application of Combination Wick-Drain Direct Connection and VacuumPre-Loading Methods in Soil Improvement of Dredger Fill
    XIE Lan-Fang, LUO Yong-Wei, XU Jian-Min
    2018, 32 (2):  126-131. 
    Abstract ( 551 )   Save
    The new dredged fill has the characteristics of high thickness, highly compressible, high water content and low permeability. The conventional sand blanket could not be placed for the drainage and as the construction access for the wick drain installation and other activities. This paper presents a case study of Reclamation and Soil Improvement of Dredged Fills of Cangnan, Zhejiang. The combination of wickdrain direct connection and vacuum preloading consolidation methods are introduced. This innovative approach is to install the wick drain and connects the wick drain directly to the vacuum pumps. A relatively hard crust at the surface could be formed due to the dewater effect. The vacuum preloading method was followed on top of the crust. The prediction results were compared with the construction monitoring results. It is concluded this method achieved satisfactory results. The advantages are: shorter construction periods, cost effective, and material savings, especially, in areas that sand supplies need to be imported.
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    Comparative Study of Reservoir Bank Railway Embankment Protection Measures
    HU Jia-Wei
    2018, 32 (2):  132-134. 
    Abstract ( 652 )   Save
    With the increasing demands for the railway passenger and cargo capacities, To expand of the existing single railway line to double lines is one of the important ways. With the constraints of station locations, and topographic conditions, the railway embankments might be constructed near the reservoir banks. As a result, the reservoir protection projects emerged.  The protection mitigation selection related to many factors, such as, the safety operation of the existing rail line, the safe and stability of the new rail line and reservoir banks, finally, the environmental concerns. The viable measures include riprap protection, piled foundation and cofferdam to isolate the embankments. These measures should also consider the geotechnical conditions and abovementioned factors.
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    Seepage Evaluation of a Reservoir Slurry Wall
    CHEN , GANG
    2018, 32 (2):  135-137. 
    Abstract ( 512 )   Save
    The seepage prevention is an important aspect in the reservoir construction and operation and therefore, the effect evaluation of slurry wall rehabilitation of results through the seepage testing is the key for the reservoir safety. This paper resents the laboratory and insitu seepage test results for a seepage rehabilitation for a reservoir.
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    Emergency Response for the Stabilization of a Mountain Slope in Qingchuan, Sichuan Province
    LUO Dong-Sheng-1, LONG Xing-2, ZHANG Kai-3, CHU Jing-Lei-3
    2018, 32 (2):  138-141. 
    Abstract ( 1091 )   Save
    The 5.12 Wenchaun earthquake resulted numerous geohazards such as soil and rock slides. Under the influence of heavy precipitation and aftershocks, the probability of slides in the slopes increases significantly and it is necessary to mitigate the hazard to ensure the safety of life and properties. This paper presents a case history of the mitigation of an unstable slope in Qingchuan County. The stability of the of the slope was analyzed through numerical simulation in accordance with the current code requirements. The results indicate that, under the strong precipitation and an earthquake magnitude of 7.0, the factor of safety of the slope is 1.07, which is marginally stable. The site visual inspection indicates that there are loose rocks accumulated on the slope due to the earthquake. These rocks are the potential safety hazards to the public since they could be fell down due to the rain or seismic actions. The mitigation measures include the removal of loosen rock, active and passive rock nets.
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    Impact of the Metro Pile Installation in Tunnel Safety RestrictionZone of the Adjacent Tunnels
    QIAO Li-Ping-1, 2 , 3
    2018, 32 (2):  142-145. 
    Abstract ( 979 )   Save
    With the largescale development of the urban construction, more and more engineering projects are in the safety restriction areas along subway lines. This paper presents a case history of the safety evaluation of the impact of the pile installation in the safety restriction zone of the adjacent tunnel on the stability of the existing tunnel in Baoan District of Shenzhen City. The Boussinesq theory was applied to obtain an analytical solution of the effective stress on the existing tunnel. The pile installation induced deformation of the adjacent tunnel was simulated with MIDAS GTS threedimensional approach. The soil squeeze effect induced by the pile installation on the deformation of the tunnel was also evaluated by the “equivalent volume” method.
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    Assessment of Anjiazhuang Tunnel Construction on theAdjacent Operational Tunnels
    ZHOU Jie-1, LUO Jun-Qiang-1, YANG Fan-Jie-2, ZHANG Wang-Jie-2, LI Pan-2, JIN Yun-Zhe-2
    2018, 32 (2):  146-150. 
    Abstract ( 718 )   Save
    The tunnel excavation will result in the stress redistribution in the surrounding rock mass and therefore induce an adverse effect on the lining of the existing adjacent tunnels. The proposed Anjiazhuang Tunnel, which is funded by Shaanxi Tongchang Energy Co., is adjacent to the rail lines of Wari and Xiaojiawa. Since the edge of the proposed tunnel is only 1.1 meters to the tunnel of Xiaojiawa line and 19.7 meters to the tunnel of Wari line, the tunnel excavation might post a serious safety hazard to the operational adjacent tunnels. This paper presents the numerical evaluation results of the stress redistribution in lining of the adjacent tunnels during the new tunnels excavation based on the actual rail tunnel locations, geological conditions and tunnel structural and geometries. A quantitative safety evaluation was performed at the most unfavorable locations at both sides of the tunnel linings in accordance with the current railway safety codes. 
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    Effect of Shielded Excavation in the Metro Tunnel on the Adjacent Existing Building Structures
    JIANG Ying, LIU Hua, HE Zhen-Hua
    2018, 32 (2):  151-153. 
    Abstract ( 822 )   Save
    When the proposed shielded tunnel excavation is close to or underneath the existing or proposed building structures, the safety of these buildings is very important and shall be warranted. The reasonable design and excavation sequence are the effective aspects of ensuring the building structure safety. This paper presents a case history of safety evaluation of Wuhan Metro No. 11 Line shielded excavation on the proposed BMW and Mercedes vehicle service buildings. Two different approaches, the shortpiled raft foundations with pile tip above the shielded excavation zone and the long pile supported ground beams with pile tip below the shielded excavation zone are compared. The results indicate that the long pile supported ground beam approach is a better way ensuring the building safety.
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    Finite Element Analysis of the Double Row Piles Supporting the Deep Excavation in Soft Soils
    WANG Feng-Mei, ZHANG Ling-Shuai
    2018, 32 (2):  154-160. 
    Abstract ( 738 )   Save
    This paper presents a case history of an evaluation of failure in the soft soil deep excavation supported by the double row piles. It is concluded that the neglecting of a soft and weak soil zone in the analysis as well as the insufficient stiffness in the supporting structure were the major causes of the failure. Three supporting mitigation approaches were proposed and each approach was examined by the finite element method using hardening soil (HS) model. The mitigation results were also ranked with internal stress and deformation aspects. The actual solution was the combination of Method 1 and Method 2. The construction monitoring data indicated that mitigation solution was successful.
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    Landslide Stability Analysis Using FLAC3D and Mitigation
    LI Feng, SUN Hui
    2018, 32 (2):  161-164. 
    Abstract ( 876 )   Save
    This paper presents the case history of a landslide evaluation and mitigation results of Shahushan in Gulou District of Xuzhou City. Factors and conditions that cause the slope failure are evaluated. The slope stability was analyzed under both normal and longterm precipitation conditions by finite element method using FLAC3D. The displacement and stress distributions in the slope were presented. The results indicate that the slope was stable under the normal conditions, however, due to the presence of weak zones, the slope might be failed under the longterm precipitation condition. The mitigation measures are suggested based on the analytical results.
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    Evaluation of Slide in a Weathered Granite Slope
    ZHOU Xing-Long-1, ZHOU Li-Hong-2, ZHOU Xing-Hua-3
    2018, 32 (2):  165-168. 
    Abstract ( 1305 )   Save
    The granite is a common bedrock type that is widely distributed in Guangdong Province which is underneath approximate 40% of the land area. The weathered granite in this region has a thick deposit depth, low shear strength when it soaks in the water and prone to develop landslide. A landslide in Maogu Village, Taibao Township of Lianshan County is a typical landslide in the weathered granite residual soils. This paper presents the landslide evaluation results and factors that cause the slide from the development of the slide and geological conditions.
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    Temperature and Moisture Variations of a Levee in the Deep-Frozen Depth Regions
    FENG Shu-Mei-1, XIAN Shao-Hua-2, LUO Xing-Wen-2, LU Zheng-2, LANG Li-Ming-1, GUAN Bo-1
    2018, 32 (2):  169-172. 
    Abstract ( 737 )   Save
    In order to study the temperature and moisture of levee in the deep seasonally frozen area during the periodic of freezing, the multifield coupling equations of the heat conduction and the moisture migration theory are adopted. The variation of the temperature field and the moisture field are simulated by the finite element method. The results indicate that: the depth of the temperature variation zone is 6 meters; The temperature field variation in the levee has laps behind the ambient temperature field, especially, this lap is increased with depth. In the process of freezing, the moisture transfers from the unfrozen zone to the frozen zone; The freezing depth of levee is slightly larger than that of the natural strata.
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    Application of Liquid Nitrogen Freezing Technique in the Shielded Excavation
    YU Gan-Liang, JIANG Wen
    2018, 32 (2):  173-177. 
    Abstract ( 912 )   Save
    Using the liquid nitrogen freezing technique in the shielded excavation in the tunnel engineering has become increasingly mature. The project case histories of applying the liquid nitrogen freezing method in the shielded tunnel excavation are summarized in this paper and the differences between the liquid nitrogen freezing method and the traditional seepage prevention improvement methods in the shielded excavation are also summarized. The statistical results on the completed projects inside China indicate that the application of liquid nitrogen freezing methods were concentrated at access portals and the maintenance and replacement of tail brushes. Compared with the traditional method, the liquid nitrogen freezing method has its own advantages.
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    BIM Method Application in Integrated Municipal Utility Culvert Project Under PPP Contracting Mode
    SUN Qing-Yang-1, 2
    2018, 32 (2):  178-181. 
    Abstract ( 677 )   Save
    The Public-Private-Partnership(PPP) contracting is a new financing method that can involve the private capital for the large infrastructure project investments and share the risk among different parties. There are many difficulties in the current utility culvert construction, the introduction of the PPP contracting mode can also improve the construction and the operation of the integrated municipal utility culvert projects. This paper presents the case of using BuildingInformationModeling(BIM) in the construction of an integrated municipal utility culvert under PPP contracting mode.
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    Construction Phase Risk Assessment for the Pakistan Neelum-Jhelum Hydropower Project
    WANG Wen-Qiao, LEI Shang-Wen, QIN Shao-Shuai
    2018, 32 (2):  182-188. 
    Abstract ( 629 )   Save
    The improved fuzzy network analysis method was applied to a comprehensive risk assessment of the construction phase risks in the NeelumJhelum Hydropower Project in Pakistan. The comprehensive and integrated analysis for risk factors and the reasonable risk assessment can help the contractors achieving the timely control the construction risks. With the combination of the Delphi Method, the Triangle Fuzzy Number method and the Network Analysis Method, an improved fuzzy network analysis method not only preserves the advantages of the network analysis method which can take the interaction of elements between various levels and the same level into consideration, but also increases “expertise” and fuzziness of the data. As a result, the innovative approach leads to a more accurate evaluation. Based on this comprehensive analysis on Pakistan's construction environment characteristics, the risk evaluation index system on the subject project has been established. And the improved fuzzy network analysis method has been employed to evaluate the risks in the construction stage of NeelumJhelum hydropower project in Pakistan. The evaluation results are identical with the most of the actual project risks that have been encountered during the construction stage, which can provide reference for the similar international projects in the future.
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    Numerical Analysis of the Long-term Stability of the Water Diversion Tunnel of N-J Hydropower Station
    HU Quan-Guang, XIONG Hao-Sen, XING Qin-Zhi
    2018, 32 (2):  189-193. 
    Abstract ( 655 )   Save
    The rheological properties of the soft rock mass have a significant impact on the longterm stability of a deep buried tunnel. This paper presents the triaxial creep test results on argillaceous siltstone samples from Pakistan NeelumJhelum hydropower project. An index rheological relationship was developed based on the test results. The parameters of the relationship were back analyzed from the construction monitoring results on the rock mass during the water diversion tunnel excavation. The calibrated parameters were used in the longterm stability analysis of the tunnel structure. The results indicate that, after 10 years of tunnel operation, the vertical deflection at the crest of the tunnel is 20.3 mm and the horizontal deformation is 18.1 mm. The stress in the lining structure is predominantly compressive with a maximum compressive stress is 63.4 MPa, which located at the crest and middle portions of the tunnel. From these analyses, lining strengthening measure should be taken.
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    Impact of a Waste Soil Disposal Site on the Safety of a Shallow Buried Tunnel
    ZHAO Ming
    2018, 32 (2):  194-197. 
    Abstract ( 648 )   Save
    Waste soils are frequently generated in the expressway construction projects. In the densely populated area, the selection of the waste soil disposal is constrained by the environmental and stability requirements. This paper presents a case history of evaluation of the effect of a waste soil site on a shallow burred tunnel. Both the equivalent soil thickness method and the Boussinesq effective stress method were used to estimate the effective stress acting on the tunnel structures with different waste soil heights. The performance of the tunnel liners under the additional stress was also analyzed. It is concluded that the equivalent soil thickness is more conservative than the Bousinesq solution. The evaluation approach of the effect of waste soil on the structural safety of the shallow buried tunnel is also suggested in the paper.
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    Effects of the Jinkou Landfill on the Quality of the Shallow Groundwater
    ZHU Fan-Ji, LIU Ya-Zhou, QUAN Feng, DENG Qing-Jun
    2018, 32 (2):  198-201. 
    Abstract ( 713 )   Save
    Currently, the landfill is a major method for the municipal soil waste disposal. The disadvantage aspects of the solid disposals become more and more prominent. One of the disadvantage is that the landfill leachate liquid accumulated at the bottom of the landfill will cause a serious pollution of the groundwater system. This paper presents the groundwater pollution evaluation results of Jinkou Landfill in Wuhan City. The groundwater at different depths underneath the landfill was sampled and analyzed. The results indicate that the groundwater system is polluted at the upper 50 meter below the ground surface. The upper perched water system is polluted by the ammonia nitrogen and the chloride compounds, and no other chemicals are detected. The lower artesian groundwater system has not been affected by the landfill leachate.
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    Vibration Propagations Studies in the Earthwork Controlled Blasting
    XU Guang-Shan
    2018, 32 (2):  202-204. 
    Abstract ( 743 )   Save
    This paper presents a case history of evaluation of the vibration propagation induce by the earthwork controlled blasting. The theoretical aspects of the blasting vibration propagation in the soil and rock media are briefly introduced. The vibration monitoring and safety control of the blasting induced vibrations are also investigated. The monitoring results indicate that the vibrations on the building structures is consistently greater than that of on the ground. A magnifying effect exists and the coefficient of magnification is decreasing with the increase of the distance to the blasting source. In the practice, the effect of magnification on the building structure should be considered.
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    Effect of the Clay Particles on the Dynamic Pore Pressure of a Saturated Sand
    CHEN Yong-Jian
    2018, 32 (2):  205-209. 
    Abstract ( 644 )   Save
    The effect of clay contents on the dynamic pore pressure in the saturated sands were studied with dynamic triaxial tests. Samples with clay contents of 0%, 10%, 20%, 30%, 40% and 50% were prepared for the tests. The failure criterion of the triaxial tested samples was set to have an axial strain of 5%. After the sample was failed, the peak pore pressure values that correspondent to each cycle were recorded. The results indicate that, when the clay content is less than 20%, the ratio of peak pore pressure increase in the saturated sand increases with the clay contents. Therefore, the clay content helps the peak pore pressure increase. When the clay content is more than 20%, the peak pore pressure increase ratio is reduced by the increase of clay content. When the clay content is greater than 40%, the increase of pore water pressure is completely blocked by the clay content, an approximately constant peak pore pressure was observed after the failure. The regression analyses were also performed on the curve fitting of the current parameters.
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    Model Study of Cement Mixed Soil Column with Tapered Rigid Inclusions
    HE Jie, XIONG Meng, GAO Jian-Xi, WANG Ren
    2018, 32 (2):  210-213. 
    Abstract ( 664 )   Save
    A model study was performed on the effect of tapered rigid inclusion in the cement mixed columns as a composite ground in the soil improvement applications. A model cement mixed soil column was prepared in a PVC pipe by layers. One instrumented cylindrical aluminum rod and two instrumented tapered aluminum rods with different taper angles were statically pressed in with a hydraulic jack. The strain in the rigid inclusions, vertical displacement of soils surrounding the rods and the rod axial resistance were measured. The results indicate that, under the lateral compression action of the soil in the penetration of the tapered rods, the surrounding soils formed the tapered shape accordingly. During the tapered rod penetration, no soil heaving within the monitoring radius of 10 centimeters. The observed minimum settlement of 1 millimeter had a distance of 10 centimeters to the center of the rigid inclusion. The penetration of the tapered rod increased with the penetration depth. 
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    Experimental Study of the Impact of Surcharge Load on the Retaining Wall in Calcareous Soils
    CHEN Wei-Jun-1, WANG Xin-Zhi-2, CHEN Min-1, YU Ke-Fu-3
    2018, 32 (2):  214-219. 
    Abstract ( 776 )   Save
    With the development of offshore oil, gas and fishery resources as well as the need of national defense, the scale of projects in coral reefs are becoming increasingly large. In the construction of island reefs, the retaining walls in the calcareous soil are often affected by external loads, and the laboratory model tests are performed to simulate the lateral earth pressures at different depths with respected to the external surcharge load. The variation of soil pressure on the retaining wall in the calcareous soils with the surcharge load is simulated under different work loading conditions. The results show that: when the surcharge is applied, the lateral earth pressure at each depth of the retaining wall increases with the increase of the surcharge. At a deeper depth, the increase rate of the lateral earth pressure becomes slower. When the surcharge loading distance is closer to the retaining wall, the surcharge load has a greater influence on the lateral earth pressure at shallower depths of the retaining wall than those of at the deeper depths. When the surcharge loading distance is further away from the model retaining wall, the surcharge load has a higher influence on the lateral earth pressure acting on the deeper depth of the retaining wall than those at the shallower depths. The form of the surcharge load includes the contact area and the contact shape of the loading, at the same loading footing area, the lateral earth pressure of a square plate is slightly larger than the lateral earth pressure induced by a circular plate. When a plate is loaded, the influence of load contact area relative to load contact shape on the lateral earth pressure on the retaining wall in calcareous soil has a larger impact.
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    The Empirical Correlations between the In-situ Point Load Tests and the Unconfined Compressive Strength of Rock
    BAI Xian-Jun, WANG Tai-Xing, WANG Xi-Kui
    2018, 32 (2):  220-223. 
    Abstract ( 1460 )   Save
    This paper presents the development of the empirical relationship between the point load test results and the unconfined compressive strength of intact rock samples of hard sandstone sample of Murree Formation of Tertiary Period in Pakistan NeelumJhelum (NJ) Hydropower Station Project. Throughout the regression analysis of test results, two different empirical relationships, linear relationship and index relationship, were developed. The point load test results could be used in the prediction of the unconfined compressive strength of intact rock samples. The compressive strength of intact rock can be used in the rock mass quality classification.
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    Advanced Geological Hazards Forecast Using TST and Its Application in the Neelum-Jhelum
    GU Jiang-Hong, SHEN Kang-Lu
    2018, 32 (2):  224-228. 
    Abstract ( 803 )   Save
    The advanced geological hazards forecast study is necessary in the construction of a water tunnel NeelumJhelum (NJ) hydroelectricity project in Pakistan due to it complicated geological conditions. The Tunnel Seismic Tomography (TST) was used in the prediction since it has a better reliability and accuracy comparing with most of the existing forecast methods. Using the FK filtering function, the surface and side reflective waves could be filtered and separated. The reflective wave from the area to be excavated could be extracted. The function of the spatial observation and the velocity scan in the TST gives the precise analyzing of the velocity from the area to be excavated.  The inverse scattering migration image can enhance an accurate geological structure locating. The application results showed that the TST method using the migration image and the velocity structure can achieve a relatively accurate advanced geological hazard forecast, compared with the actual geological sketch, which can provide the reference for the field geological tectonic analysis and the surrounding rock mass classification.
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    Physical and Mechanical Properties of a Tailing Sand Under Construction Conditions
    XU Fan, YANG Yong-Jing, LI Ji-Quan
    2018, 32 (2):  229-232. 
    Abstract ( 679 )   Save
    The proposed tailing reservoir is located at the Qianglanggou gully in the southwest of the Second Phase Development of the Jiala Copper Polymetallic Deposit in Huatailong Mine, Tibet. The tailing dam fill material is predominantly waste soil and rock from the mining operation. The additional borrow material should be directly from local site with a priority consideration of areas inside the reservoir. This paper presents the geotechnical test results on the tailing sands and other materials under construction conditions. The tested items are: Physical and mechanical properties of tailing sands, in-situ plate loading test and mold bag vibration compact tests. The results indicate that, the moisture content and density are significantly affecting the mechanical properties of the tailing sands; 
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    Experimental Study on the Hydration Thermal Effect ofa Large Diameter Caisson Using BOTDA
    ZHANG Hong-Song, PANG Cheng-Li, HU Jian-Wei
    2018, 32 (2):  233-237. 
    Abstract ( 765 )   Save
    In the curing process of mass concrete structures, due to the hydration heat accumulation during the condensation stage of the concrete, the internal temperature of the concrete rises sharply, and a great temperature difference appear compared with the outside temperature of the concrete structure. When the differential temperature exceeds a certain level, the tensile stress of the structural surface exceeds its limiting range and then it could result in the temperature cracks inside the newly poured concrete. The Brillouin Optical Time Domain Analysis (BOTDA) temperature measurement technique has the advantage of all distributed mode, high accuracy and easy measuring. The BOTDA distributed optical fiber temperature measurement technology was applied to the longterm measurement of hydration thermal temperature of a large diameter concrete caisson in a landslide mitigation project in Badong third Middle School. Combined with the traditional temperature measurement methods, a longterm temperature monitoring data were obtained. The analytical results show that the BOTDA distributed optical fiber temperature measurement technique applied to the temperature monitoring of the solidification stage of the pile concrete, has the significant advantages over the traditional temperature monitoring method. The new method is able to response to the temperature change along the entire caisson length in a timely and accurately manner, and provide a realtime data.
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