bluuebunny/crossref_metadata_2025 huggingface dataset:
The Seismic Frequency Response Function Calculation of Multi-Span Simply Supported Girder Bridge
Authors: Ma Qing Qing , Zhang Hong Ru
Published: September 2013

In order to simplify the analysis and calculation of multi-span simply supported girder bridge, the seismic frequency response function equation of longitudinal vibration for single-span simply supported girder bridge is established, based on the Fourier transform of the motion equations of multi-degree-of-freedom system. The calculation method of the seismic frequency response for the vertical moment and displacement of multi-span simply supported beam bridge is proposed according to the transfer matrix principle. Taking a bridge of Qinghai-Tibet Railway as an example, the maximum displacement and moment are solved. The result shows that: the displacement of the control section of the side spans is smaller than that of the middle of the bridge, while the moment is opposite. The corresponding Fourier amplitude spectrums under the pulse loads are given finally.
3D Vs. 2D Modeling of Concrete Gravity Dam Subjected to Mining Tremor
Authors: Dulinska Joanna M. , Galuszka Anna
Published: September 2013

The paper indicates the role of 3D modeling of concrete gravity dams in evaluation of dynamic response of dams to mining tremors which occur in mining activity regions. 2D and 3D models of a concrete gravity dam were prepared in order to compare two-and three-dimensional analysis of the dynamic response of dam to mining shock. Firstly, values of natural frequencies obtained for 2D and 3D models occurred to be very similar, but only the 3D model allowed to predict the dam behaviour under longitudinal kinematic excitation. Secondly, the comparison of the maximal principal stresses obtained for 2D and 3D models indicates that the simplified 2D analysis underestimates the values of dynamic response on about 20 %. Three-dimensional dynamic analysis allows to assess internal stresses resulting from mining shock more precisely, since the amplitudes of ground vibrations during mining tremors are comparable in three directions.
Analysis of the Reinforced Masonry on Displacement Response
Authors: Yu Yang , Zhuang Xin Jun , Zhang Yun Feng , Zhang Jie Dong
Published: September 2013

It is very important to develop reinforced block masonry structure system with a good anti-seismic performance and convenient construction. This paper mainly researched the displacement response of the reinforced masonry structure under earthquake. The maximum storey drift and displacement of the structure are calculated in Y direction by numerical analysis method.
Coupled Elastoplastic Analysis of Dam Seismic Stability
Authors: Fei Kang , Tian Fei , Zheng Qian
Published: September 2013

A nonlinear procedure for coupled elastoplastic analysis of the dam seismic stability was presented in this paper. The soil nonlinear dynamic behavior was modeled using by a multiple yield surface model based on the numerical framework of u-p formulation. The strength reduction method was used to determine the factor of safety of dam slope and the location of failure surface. A case study of a 293.5 m high clay core rockfill dam was used to demonstrate the application of the method. Based on the computed results, it is founded that the maximum acceleration amplification coefficient is 1.72, which is almost 20% less than that obtained from the equivalent linear analysis. The most dangerous slip surface was at the shallow zone of the lower part of the upstream slope, which was different from the predicted location from the equivalent linear analysis. The earthquake induced pore water pressure and permanent deformation were also studied in detail.
Study on Seismic Dissipation Energy Based Nonlinear Single-Degree-of-Freedom Model
Authors: Bao Wen Bo , Xu Guang Yang , Li Yong Chen
Published: September 2013

Based on the energy-based design approach, variation of seismic dissipation energy with structural properties is investigated by using the SDOF model and the trilinear constitutive. The influence of structural ductility on hysteretic energy, damping energy, hysteretic energy ratio and damping energy ratio is investigated, and the evolution trend of hysteretic and damping energy spectra with ductility ratios and damping ratios is examined for structures subjected to the north south component of El Centro, the Imperial Valley, California earthquake of May 18, 1940.
Effect of the Bed Sand Wave on Cross-Section Discharge Measurement and Calculation in Physical Model
Authors: Wan Qiang , Cao Yong Tao
Published: September 2013

t is analyzed of the effect of the bed form change on the cross section flow measurement and calculation in the flume with the sand ripple bed or smooth bed. The reason is researched that the flow measurement error is caused by the river bed ripple. The Correction method is analyzed under the condition of different discharge and riverbed morphology. So the support is provided in order to improve the physical model discharge measurement accuracy.
Analysis of Multi-Year Drought in Guizhou Province and Research of Drought Resistance Measures
Authors: Zhang He Xi , Chi Dao Cai , Wang Yong Tao , Liu Liu
Published: September 2013

This paper illustrated the drought resistance strategy, analyzed the profile, characteristics, development tendency and the cause of the drought in Guizhou Province. And the paper analyzed the major measures and achievements of the drought resistance emphatically to provide a reference basis for Guizhou drought resistance.
Some Characteristics of Peak Flow in the Richelieu River, Quebec
Authors: Li S. Samuel
Published: September 2013

This paper presents a statistics analysis of 1938-2012 data of daily discharge and water level collected from a gauging station on the Richelieu River in Southern Quebec, Canada. Using the most recent data, this paper aims to update flood characteristics from previous decades old analyses. Such update is important to the flood-prone region. The present analysis covers peak flow magnitude, duration, timing and, more importantly, their changes. The main findings are: There are no significant changes over time in average magnitude of floods, but there are increasing fluctuations between low and high peak discharges. The distribution of annual peak discharges shows a signifcaint shift of skewness from left to right; if this condition persists, future floods are expected to have a larger magnitude than historic flood events. The timing of peak discharges has not shown any significant trend of changes. A new flow rating curve has been obtained for discharge estimates.
Photosynthetic Performance of Potato (Solanum tuberosum) Subject to Water Deficit Regulated with Mulched Drip Irrigation
Authors: Zhang Heng Jia , Li Jing
Published: September 2013

An experiment was carried out to determine the effect of mulched drip irrigation under water deficit on leaf area index (LAI), leaf area duration (LAD), dry matter (DM) and relative growth rate (RGR) of potato in an arid environment. Five water deficit treatments and a full irrigation control were established to subject potato to various levels of soil water deficit at different crop growth stages. The result indicated that potato LAI and LAD at all the determined growth stages were not reduced under water deficit regulation. Additionally, the DM and RGR at starch accumulation were not significantly decreased under water deficit either. Therefore, medium soil water deficit regulated at 55%~65% of field capacity with mulched drip irrigation at potato tuber initiation could be used to effectively improve leaf area index, leaf area duration, dry matter and relative growth rate of plants.
Trend Analysis of China Flood Disaster and Challenges in the Future
Authors: Liu Jian Fen , Zhang Xing Nan , Wang Hui Min
Published: September 2013

China is a country with frequent floods from ancient periods, caused by its complicate topology, higher in western regions, lower in eastern regions, consisting of three kinds of terraces, and precipitation variance at different seasons in a common, heavy or scare year. Challenges from floods are increased together with climate change, land use change and urbanization development, particularly, extreme rainfall events occurring with a high frequency. Four kinds of flood damage data time series including affected area, damaged area, dead population and collapsed houses from 1950 to 2010 from Bulletin of Flood and Drought Disaster in China in 2011 will be applied to trend analysis of floods by MK test. The results indicate that affected area and damaged area have significant upward trend, dead population has significant downward trend, damaged houses has no significant upward or downward trend. Keywords: Trend Analysis; Flood Damage; Mann-Kendall Test; Data Series
Discussion on Ground Motion Parameters of JiYin Hydraulic Project
Authors: Tang Li Hua , Li Shan You , Chen Jian Bo
Published: September 2013

JiYin hydraulic project is located at the branch of Keliya River, Yutian county of Xinjiang. During the stage of its planning and design, a magnitude 7.3 earthquake occurred 43km away from the southeast of the dam. As the earthquake was in the southeastern part of Altyn Tagh Fault which was recognized in the past as a low seismicity segment, the cognition about seismic surroundings had changed totally. Based on comparison between the two seismic safety evaluations on JiYin before and after the earthquake, epistemic uncertainties in probabilistic seismic hazard assessments have a significant effect on final results. Therefore, in order to mitigate earthquake disasters of dams, combination of probabilistic and deterministic methods should be applied for evaluating seismic hazards when large dams are constructed in strong seismicity regions.
Impounding in Advance for Three Gorges Reservoir by Considering the Downstream Drought Resistance
Authors: Li Ying Hai , Peng Tao , Liu Ji , Dong Xiao Hua
Published: September 2013

To solve the contradiction between Three Gorges reservoir impounding and downstream drought resistance in flood recession period, impounding in advance scheme is studied in this paper. Firstly, an improved impounding mode by strictly satisfying the downstream drought resistance discharge constraints is proposed. Then, by comparing from the aspects of annual average fill storage rate, final water level, power generation, surplus water and flood risk of different impounding time schemes, the optimum improved impounding scheme is determined and validated by typical year 1996. The study can proved scientific guidance for drought control of Three Gorges reservoir.
Decision Support System for the Management of Water Resource System in Ningxia
Authors: Feng Ke Peng , Tian Jun Cang
Published: September 2013

The decision support system (DSS) developed to support the management of the water resource system of Ningxia are presented. The DSS includes information component system that performs data acquisition, management and visualization. In GIS module, Google Earth and ArcGIS are integrated, through KML (KMZ) files for data exchange, provides integrated services and decision support for the management of water resources. Model component performs simulation and optimization of the water resources. The models, which are the focus of the present work, reorganized into two main parts. The first one is water demand forecast model, which, based on the analysis of historical hydrological data, generates forecasts of the water demand amount. The second one allows the detailed study of the water resources implementing the optimization methodology. The mathematical method performs the allocation of the water resources to the different system components, keeping the number of control variables small, even for complex water resources like the one under study. The DSS is now in the final stage of its development and its results, some of which are summarized in the paper, have been utilized to support the water resources management. This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. The best is to read these instructions and follow the outline of this text.
The Optimal Selection of Irrigation Systems Based on the Evidence Theory
Authors: Liao Zi Long , Long Yin Hui , Wei Yong Fu , Guo Zhong Xiao
Published: September 2013

The optimal selection of irrigation systems is a complex process that contains lots of uncertainty factors, such as the influence of natural resources, technical level, the environment, economic and society conditions. With analyzing the present water resources utilization of Ordos City and considering the available research achievement of water-saving irrigation, this paper select technology, resources, environment, economy, society as the primary indexes that contains its 28 subordinate secondary indexes, establish irrigation systems optimization model, then determine the appropriate value of decision under the effects of different indexes and establish a corresponding knowledge matrix. In the last, DS combination rule is used to calculate the optimal value of different knowledge matrixs basic probability assignment, and the research results shows that the optimal value of Ordos city from high to low in turn are reeling sprinkler irrigation, large clockwise sprinkler irrigation, mobile sprinkler irrigation, low pressure pipe irrigation.
Compressed Structured Storage for Saving Hydrological Model Results
Authors: Xiang Xiao Hua , Wu Xiao Ling , Niu Shuai
Published: September 2013

Hydrological models are always related to time and spatial domains, so the model results produced by these models are very large. Microsoft component structured storage can be employed to save the model results, but it is lack of mechanism to reduce the data size. In order to tackle this situation, compressed structured storage method is introduced which based on combining component structured storage and zlib compression library. In this method, standard component rules are complied and containment as most common mechanism for object reuse in COM is applied so as to simplify the usage.
Research on Characteristics of Sediment in Yichang-Wuhan Reach after Impoundment of the Three Gorges
Authors: Yang Yan Hua , Liu Xiao Qiang , Zhang Hong Qian
Published: September 2013

Reservoir regulation make conditions of sediment under the dam change greatly after impoundment of the Three Gorges Project. This paper analyzes change trend and abrupt change situation of incoming sediment and studies characteristics of new sediment of Yichang and Hankou Stations after impoundment of the Three Gorges with Mann-Kendall nonparametric rank test method. The result indicates that after operation of the Three Gorges Reservoir, annual sediment runoff changed suddenly and sediment runoff reduced sharply in Yichang and Hankou Stations; sediment entering the Yichang-Wuhan reach decreases substantially and it almost can be regarded as clean water discharge. Research shows unsaturated degree of the clear water released from reservoirs decreased after obtaining sediment along the river, so the sediment discharge would be partly recovered.
Water Consumption of Potato (Solanum Tuberosum) Grown under Water Deficit Regulated with Mulched Drip Irrigation
Authors: Zhang Heng Jia , Li Jing
Published: September 2013

An experiment was conducted to determine the effect of mulched drip irrigation under water deficit on soil water content (SWC), stored soil water (SSW), daily water consumption (DWC) and ratio of water consumption in total water use (RWC) of potato in an arid area. Five water deficit treatments designed to subject potato to various levels of soil water deficit at different crop growth stages and a full irrigation control were established. The result indicated that the maximum SWC was at 20 cm depth in soil profile and that in 10 to 40 cm increment varied sharply during potato growing season. The SWC, SSW, DWC and RWC were significantly affected by mulched drip irrigation at water deficit regulation stages except at starch accumulation. Therefore, proper levels of soil water deficit regulated with mulched drip irrigation at proper plant growth stages could be used to regulate soil water status, stored soil water and crop water consumption effectively.
Flow Patterns and Bed Deformation in a Meandering Channel with Different Flow Conditions
Authors: Jia Dong Dong , Hei Peng Fei , Shao Xue Jun , Zhang Xi Bao
Published: September 2013

The velocity distribution and bed deformation patterns in a meandering channel with consecutive bends were investigated by using both an experimental study and a 3-D flow and sediment transport model. The simulated results from the 3-D model agree well with the experimental data. The flow structure and bed deformation patterns in channel bends with different flow conditions were analyzed. Modeled results demonstrated that the velocity distribution and bed deformation in the meandering channel depend mostly on the flow regimes. For the case of small flow discharge, the maximum velocity occurs in the vicinity of concave bank. For the case of large discharge, the maximum velocity occurs near the center part of the channel. Consequently, bed deformation patterns in meandering channels will be influenced by the flow conditions.
Cause Analysis and Stability Estimation about Taziping Landslide
Authors: Dai Yun Yun
Published: September 2013

Taziping Landslide is in the border of Ganluo County. Its a medium-sized landslide performed by two slip masses, an upper one and a lower one. Now its in the stage of creep deformation, which potentially threatens people's lives and property. This paper analyses landslide geology, characteristic and creeping formation mechanism of Taziping landslide. And then evaluate its stability by transfer coefficient method. Lastly put forward the comprehensive improvement scheme, retaining project as well as surface drainage.
Hazard Assessment of Debris Flow Based on the TFSE: A Case along Jinsha River close to the Jinsha Dam Site in China
Authors: Shan Bo , Wang Qing , Chen Jian Ping , Xiong Hui
Published: September 2013

Debris flows are common natural hazards in China. The outbreak of debris flows in reservoir region not only affects the stability of the hydropower stations dam, but also threatens the safety of human life and their property. Therefore, hazard assessment and protection of debris flows close to the dam are necessary and important. In this paper, SPOT5 remote sensing images and DEM model and scene investigation are introduced to acquire the characteristics of debris flow gullies. Ten debris flow occurrence related factors were selected. Then, on the basic of analyzing the relationship of the major factors and fuzzification of debris flow hazard degree, the model of two-stage fuzzy synthetic evaluation (TFSE) was established for hazard assessment. The debris flow risk under different designed rainstorm frequency was calculated. By the evaluation results, we can know that with the design storm intensity increases, the risk of debris flow increases, which is consistent with the actual situation.
Fire Test on Two-way Simply Supported Concrete Slab
Authors: Yang Zhi Nian , Dong Yu Li
Published: September 2013

This paper describes the results of a fire test conducted on two-way simply supported concrete slab. The details of support condition, arrangement of reinforcement, position of displacement transducers and thermocouple trees are described. The experimental results such as the temperature distributions within the slab, vertical deflections and horizontal displacements are presented. The experimental results show that the temperature distribution along the slab depth was nonlinear and the temperature gradients in the slab were large. Three main cracks parallel to the short span direction occurred on the top surface of the slab. It is shown that two-way simply supported concrete slab has good fire resistance.
Seismic Upgrading Strategy for Near-Fault School Buildings in Taiwan
Authors: Hsiao Fu Pei , Lo Hui Hsien , Chien Wen Yu , Hwang Shyh Jiann
Published: September 2013

All types of school buildings were seriously damaged in Taiwans 921 Chi-Chi earthquake. Seismic evaluation and retrofit of these numerous vulnerable school buildings has become an important issue to be resolved. The National Center for Research on Earthquake Engineering (NCREE), Taiwan assisted the Ministry of Education on the arrangement of programs to accelerate retrofit and rebuilding works of elementary school, junior high school, senior high school and vocational school buildings, as part of the project called, Economic Recovery Act. Based on the database for seismic assessments and retrofits of school buildings, this study recommends a seismic upgrading procedure of near-fault school buildings. The proposed procedure can control effectively the seismic upgrading progress of near-fault school buildings. It also provides suggestions on the seismic retrofitting and reconstruction plans of near-fault school buildings to reduce damages and losses in a possible seismic event.
Study on Spread of Fire Overflow on Building Facades with Insulation Materials
Authors: Li Yan Feng , Xu Cong Cong , Xing Xue Fei , Zhang Jin , Hu Cheng
Published: September 2013

Fire overflow on exterior wall with thermal insulation system has been studied by numerical simulation. The spread laws of fire overflow are analyzed through the temperature distribution near the window. The computational results are compared with those of test in the Exterior Insulation Fire Barrier Technical Guidelines (EIFBTG). It has been found that the calculated maximum temperature points is closed to the test on the first floor, the first ceiling, and the points near the above two windows. However, there are differences between two kinds of results above two floors and ceilings, and the points near the first window. It has also shown that when the HHR is 7.5KW, the scope of damage of exterior thermal insulation layer is about 15 square meters near the window. The research would provide reference for fire protection design of exterior wall thermal insulation in the high-rise buildings.
A MRACO Algorithm for Structural Multi-Damage Detection
Authors: Lin Jing Chun , Yu Ling
Published: September 2013

A new MRACO identification algorithm is proposed for structural multi-damage detection through combining MapReduce procedure and ACO method in this paper. Four classical benchmark functions are first employed to evaluate convergent performance of the MRACO algorithm, which pursues a global solution to combination optimal problem with constrained conditions. Then, a series of numerical simulations on constrained optimal problem about structural multi-damage detection of a two-story rigid frame have been conducted for assessing the applicability of the new MRACO algorithm applied to the structural damage detection field. Finally, some illustrated numerical results show that the MRACO algorithm can not only locate the structural multiple damages but also effectively quantify the severity of damages with higher accuracy and good noise immunity.
The Economic Loss Estimate of Dam Break Based on 2D Dam Break-Wave Numerical Simulation
Authors: Shen Zhao Wei , Pan Cun Hong , Ye Sui Gao , Lu Hai Yan , Wang Li Hui
Published: September 2013

A 2D numerical model based on Boltzmann equation and an unstructured FVM grid with a kinetic flux vector splitting (KFVS) scheme was developed to simulate dam break-wave. As an example, propagation of the dam-break wave of one reservoir dam at Yuhang District of Hangzhou in Hangzhou was simulated by this model. Using regional economy, population, and geography data of 2008, the economic loss caused by dam failure was evaluated. The result shows that total economic loss is about 20% of the GDP in Yuhang, which is close to the conclusion of some existing researches. It is foreseeable that this method would to be used more widely in Zhejiang for dam safety management.
Design of a Safety Monitoring and early Warning System for Cascade Reservoirs Based on Web-GIS Platform
Authors: Li Li Bing , Jiang Yun Hui , Lu Zheng Chao , Shang Feng
Published: September 2013

Against the background of applying geographic information system (GIS) technology in the water industry, the application of Web-based GIS (Web-GIS) for displaying and managing the safety of cascade reservoirs is introduced. Moreover, the system architecture and development platform, together with the design of the database, function, and user interface for a safety monitoring and early warning system for cascade reservoirs based on the Web-GIS platform are put forward and illustrated. The key technologies, which include data fusion and a monitoring index system involved in system development, are also proposed. The system is capable of visualization design and improves the ability of realizing real-time early warning for cascade reservoirs.
Experimental Study on Side Friction of Uplift Bored Piles in Soft Rock
Authors: Hu He Song , Tang Meng Xiong , Zhang Cheng Lin
Published: September 2013

Based on the experiment of frictional resistance between concrete short pile and lightly weathered silty mudstone, the frictional resistance of concrete short pile on uplift loading was analyzed and the ultimate friction resistance was obtained. Considering the site geotechnical investigation report and relative standards, the safety factor of side friction of uplift bored piles in soft rock was defined according to the testing of frictional resistance between concrete short pile and lightly weathered silty mudstone. Achievements in this research are already applied into engineering practice.
The Effect of Negative Temperatures of Frozen Clay on Dynamic Strain Amplitude
Authors: Luo Fei , Cai Cong , Zhu Zhan Yuan , Cui Ling Zhi
Published: September 2013

Authors studied variation characteristics of dynamic strain amplitude of frozen clay with different temperatures by MTS-810 vibration tri-axial material testing machine. Results show that the variability is carried by instrument errors, operation errors, and so on. The average values are used to eliminate the variability of test results. With the increasing of the load levels, dynamic strain amplitude increases gradually. Negative temperature has a lager influence on the variation characteristics of dynamic strain amplitude, however, the influence is smaller when temperature above freeze points of water in the soil; when the temperature below it, dynamic strain amplitude changes with decreasing temperature; when temperature below-4°C, dynamic strain amplitude has no change with decreasing temperature. Dynamic strain amplitude grows with increasing dynamic stress amplitude.
Experimental Study on the Corrosion Law of Chloride in Concrete under Artificial Climate
Authors: Wan Yi , Yu Zhi Wu , Liu Peng , Sun Yu Yan
Published: September 2013

Corrosion experimental were conducted in order to study concrete samples of two strength grades during different erosion period under the condition of designed artificial chloride erosion.Through drilling powder of concrete surface at various depths,chloride ions’concentration at different depths of corroded samples were determinated,and the diffusion coefficients of chloride ion after 90,180,240 days of corrosion were calculated on the basis of Fick’s second law.It turns out that obvious convection zone exitsin corroded concrete,and the thickness of convection zone increases with the erosing time and the reduction of concrete strength grade.In addtion,fitted datas of chloride ion diffusion coefficient increases with the reduction of concrete strength grade.
Expansion of Cement Mortar Mixing Expansive Agent under Different Curing Conditions and Compressive Strength in Constrained Conditions
Authors: Wu Yuan Yuan , Peng Yuan , Liu Yong Dao , Jia Li Li
Published: September 2013

The expansion of cement mortar mixing expansive agent under standard curing and membrane curing conditions and compressive strength in constrained conditions are studied in this paper. Results show that the early expansion effect of calcium sulphoaluminate hydrate-calcium hydroxide expansive agent is obvious, mid-to late effect of magnesia expansive agent increase clearly. Compare with standard curing, the shrinkage of the basic cement mortar increase and expansion effect of expansive agent reduce under membrane curing. The expansion effect of expansive agent B is good and persistent under membrane curing, its applicable to used in the closed environment, such as concrete filled steel tubes. The compressive strength of mortar with expansion agent is a little more than the basic mortar under the condition of limit.
Calcinations Regulation Effect on Activity and Hydration of MgO from Magnesite Tailings
Authors: Shen Hua Rong , Jiang Yang , He Wei Zhong
Published: September 2013

List The active of MgO was produced from magnesite tailings under certain conditions. The effect of calcinations temperature on the crystal structure of MgO was analyzed by XRD and SEM. Crystal particle of MgO was calculated according to Scherrer formula. The microstructural differences between the MgO agglomerates were examined by SEM at different temperatures. The activity of MgO was evaluated though conductivity which was measured by the conductivity meter. The activity of MgO effected by calcinations temperature was studied. The result showed that magnesite tailings was fully decomposed when that was calcined for 60min with the calcinations temperature of 1050°C, and the activity of MgO was very high. Established a hydration and expansion model of MgO is proposed to explain the activity of MgO.
Stability Analysis of Slope under the Condition of Rainfall Infiltration
Authors: Xiang Guo , Wang Cheng Liang , Bai Ming Zhou , Xu Zhao Yi , Yan Jun Jun
Published: September 2013

Landslide instability hasplenty of influential factors. However, shown by considerable practical casesof landslide instability, rainfall is considered to be a major element leadingto landslide. Rainfall increases the weight of slope mass, while reduces itsstrength parameter. Rainfall may as well create water pressure inside theslope, while water pressure has significant influence on landslide stability.In the paper, finite difference software FLAC3D is adopted toperform a numerical simulation on practical landslide, with the objective tofigure out the safety coefficient and stress-strain property of landslide undernatural state and waterlogged state, to analyze the possibility of landsliderenewal and to provide reference for researches on similar landslides in thearea.
Mineral Waste Coupled with Boron Oxide for Producing Active Belite Cement Clinker
Authors: Liu Yan Jun , Zheng Yong Chao
Published: September 2013

This paper presents a laboratory study on active belite cement clinker using boron oxide as dopant to stabilize high temperature phases of Dicalcium silicate (C2S), and mineral waste as siliceous materials in complete replacement of clay. The clinker samples were soaked in Muffle Furnace at different burning temperatures and for various time durations, and then, cooled down to room temperature using air blower. Quantitative X-ray Diffraction analysis (QXRD) by Rietveld method indicates that major mineral components are Dicalcium Silicate (C2S), Ferrite (C2 (A0.48F1.52) O5) and trace amount of Tricalcium Silicate (C3S) in the cement clinkers. Among them, Dicalcium silicate is over 85 percent, Ferrite around 10 percent and Tricalcium silicate less than 10 percent. Thermogravimetric and Differential Scanning Calorimetric (TGA-DSC) spectrum shows that there is no significant phase change while cement clinker was cooling down, which means significant amount of high temperature polymorphic C2S was stabilized during cooling process. It is agreeable with the results from QXRD analysis. Specifically, among polymorphic belite phases, αH-C2S accounts for around 66% of cement clinker, and αL-C2S for about 22% of cement clinker. In addition, massive belite phase was identified by Scanning Electronic Microscope (SEM) analysis and Light Microscopy analysis. At last, the mechanical tests on active belite cement show that active belite cement clinker has a slow strength development at early ages, but rapid strength gain at 28 days in comparison with belite clinker without adding boron oxide. Thus, this active belite cement clinker demonstrates very promising prospect in sustainable cement industry development.
Keywords: Active Belite Cement Clinker; Doped; Boron Oxide; αH-C2S; αL-C2S; Strength Development
Cause Analysis on the Cracks in Concrete Plate of Canal Lining
Authors: Cui Jian Hua , Xie Zhi Qiang , Xiao Han Jiang
Published: September 2013

Concrete cracks often appear in construction period and operation period of the canal lining. For analyzing the cause of these cracks, the factors which will cause cracks are classified based on the data collected. Also sensitivity analysis on these factors is carried out with 3D contact nonlinear finite element method. The result shows that, the factors which resulting in concrete cracks are temperature variation, humidity, uneven settlement of foundation, expansion deformation of foundation soil, external loads etc.; Joint-cutting should be done as soon as possible, expansive property of the foundation soil and construction quality of canal lining should be strictly controlled.
The Early-Age Drying Shrinkage of Cement-Based Materials with the same Workability after Temperature Compensation
Authors: Zhang Li Feng , Lai Jun Ying , Qian Xiao Qian , Shen Chong
Published: September 2013

The early age drying shrinkage of cement-based materials with same the same workability staring from the initial setting time was studied. Superplasticizers (SP) were used to get the same workability. The drying shrinkage of paste was measured by clock gauge, and CABR-NES deformation instrument was used to measure the shrinkage of concrete. Temperature probes were buried into both paste and concrete specimen cores to measure the temperature curve, and temperature deformation was considered into the early shrinkage. Results show the addition of SP increases much more shrinkage than the control group, and polycarboxylate SP increases more shrinkage than naphthalene SP. The different temperature peak time of different mixtures show that the addition of SP changes the hydration process of cement, and the shrinkage of cement-based materials after temperature compensation is bigger than the measured value in the first 6 hours, but the gap is not big.
Researches on the Coal Fly Ash Applied to Saline Soil Improvement in Rural Roads
Authors: Guo Zhi Dong , Zhang Xue Jun , Liu Yan Rong
Published: September 2013

There is a wide range of saline soil distributied in China , 4.88% of the country's land can be used for salinization land.The salinization of soil in Tianjin area is 6614200 acres among them.The saline soil characteristics of collapsibillity, expansion, corrosion resistance are easy to make the roads salt cause expansion deformation, melting trap net crack and potholes, falling off and any other diseases, thus it is currently an urgent need to solve the problem of saline soil improved road in the salinization area of rural highway construction.Research group in the Green Meadow Depression saline soil application, applies the power plant fly ash resources based on the technology support analysis, obtains feasible technology application results.
Experimental Study on the Capillary Absorption of Cement-Based Materials and Analysis of Influencing Factors
Authors: Li Xin , Jin Nan Guo , Tian Ye , Jin Xian Yu
Published: September 2013

Capillary absorption effect is very important to the research of concrete durability. Initial surface absorption test (ISAT) method has been employed to investigate the effect of W/C, age, aggregate volume percent and concentration of NaCl solution as a transmission medium of the capillary absorption of the cement-based materials. Experiment results indicate that, the capillary absorption coefficient increases with the increasing of W/C, but decreases with the increasing of age and aggregate volume percent. Within a certain range of low concentration, the capillary absorption coefficient increases with the increasing of the concentration of NaCl solution, however when the concentration is too high, the transmission rate will be lower than pure water. This investigation provides an experimental foundation for the durability design and service life assessment of concrete structures.
The Research of Anti-Cracking Performance of Ceramists Concrete Beams
Authors: Yang Jian Yu , Mo Zhen Lin , Yang Wei Jun , Tan Wei
Published: September 2013

This paper displays the crack load failure pattern and influences on crack load of reinforced ceramists concrete beams in different reinforcement ratio, concrete cover thickness and diameter of rebar through the experimental study of bending anti-cracking property of 8 reinforced ceramists concrete beams, and proposes the method of calculation cracking moment of normal section for ceramists concrete beam.
An Experimental Study on the Contribution of Fire Retardant Coating to the Fire Protection of Concrete
Authors: Cao Wei Jun , Ou Man Li , Liu Fang Cheng
Published: September 2013

The mechanical property of the concrete under high temperature will go through great changes with much greater deformation. The uneven temperature distribution causes equilibrium temperature stress of the cross section and deformation of components, thus damaging the structure system of the concrete. This paper conducts a high-temperature test on the C25 concrete specimen with fire retardant coating, compares the test result with the test on the C25 concrete specimen without fire retardant coating, and analyzes the protective role of the surface fire retardant coating in the concrete structure buildings in case of fire.
Mechanical Properties Contrast Between Fiber Reinforced Composite Poles and Traditional Poles
Authors: Gong Jing , Ren Dong Xue , Zhou Chao , Ma Guo Qing
Published: September 2013

Take advantages of concrete to improve the stiffness of fiber reinforced composite material(GFRP), reference to the existing dimensions of concrete-filled steel tube pole, applicate GFRP-concrete structure in 35 kV transmission line. Change the various parameters of the poles in ANSYS, compare the maximum deformations and the maximum stresses of GFRP tube-concrete pole and concrete-filled steel tube pole. Results show that different parameters have different impacts on the mechanical properties of the poles, suitable parameters of GFRP tube-concrete pole were got and the technical specifications of the application of GFRP in various voltage levels should be perfected.
Freeze-Thawing Damage Model of New-to-Old Concrete with Different Rough Interfaces
Authors: Yi Cheng , Lai Su Ling , Zhu Hong Guang , Yan Shi Hong , Liu Jian Xia , Dong Xin
Published: September 2013

New-to-old concrete freeze-thawing durability affects the safety and normal service of structure. In this paper, the freeze-thawing resistance of new-to-old concrete with different rough substrate surfaces was studied. The roughness of substrate surface was characterized by fractal dimension. Test results show that freeze-thawing damage of new-to-old concrete has two stage changes: first stage, freeze-thawing damage increases rapidly, mainly caused by the damage of interface; second stage, freeze-thawing damage increases slower, mainly reflects damage of substrate and overlay. Compared with smooth surface, rough surface can significantly improve freeze-thawing resistance of new-to-old concrete. In a certain range, with the increase of fractal dimension, the freeze-thawing resistance improves. When the fractal dimension is beyond the range, the freeze-thawing resistance impairs while the fractal dimension increases. A freeze-thawing damage model applied to new-to-old concrete is proposed, and a good correlation is found between the model and experimental results.
Study on Preparation Experimental about High-Permeability Layer-Penetration Oil
Authors: Du Qin Wen , Fang Yu , Yu Bin , Wu Xia
Published: September 2013

Aiming at the problem that the permeability, bond performance and waterproof property of the layer-penetration oil used in the highway engineering is poor, this article puts forward and develop a kind of high-permeability emulsified asphalt layer penetration oil. This layer-penetration oil is the emulsified asphalt that mixed by the tyre pyrolysis asphalt and the SK 90# asphalt, added by penetrant, emulsifier and curing agent, emulsified by the colloid mill. Some indoor test for this layer-penetration oil have been done. All these tests show that the layer-penetration oil has good permeability and good bond performance after the infiltration of the grassroots demulsification. So we can see that it has excellent engineering value and it is worthy of popularization and application.
Elastic Solutions for a Saturated Isotropic Half Space Subjected to a Fluid Line Sink
Authors: Lu John C.C.
Published: September 2013

The study derives the closed-form solutions of the long-term elastic consolidation subjected to the fluid line sink in a homogeneous isotropic elastic half space aquifer. The Hankel transform in a cylindrical coordinate system is employed to develop the analytical elastic solutions. Derivations of governing equations are based on the mathematical model of Biots theory of poro-mechanics, and the half space aquifer is modelled as a saturated porous stratum which is bounded by a horizontal surface. The total stresses of the aquifer obey Newtons second law and Hookes law. Besides, the mass conservation and Darcys law are introduced to formulate the governing equations of pore fluid flow. The software Mathematica is used to complete the symbolic integrations and obtain the closed-form solutions. The solutions can be applied in dewatering operations of compressible aquifer.
A Study of Effect Factors on Sodium Silicate Based Expanded Perlite Insulation Board Strength
Authors: Tian Ying Liang , Guo Xian Long , Wu De Long , Sun Shi Bing
Published: September 2013

Because of low strength, the expanded perlite insulation boards application in building energy saving is restricted. This paper discuss change rules of the expanded perlite insulation board apparent density and mechanical strength with adjusting the amount of sodium silicate, pressing pressure, heating system. It turned out that good thermal insulation performance and high strength expansion perlite insulation board is prepared by mass ratio of 2.5:1 of 30% of the content of solid sodium silicate solution to expanded perlite, 0.38MPa of pressing pressure and 105°C condition of heating temperature.
Synthesis, Cement Paste Fluidities and Molecular Weight Measurements of Polycarboxylate Superplasticizer by Bulk Polymerization
Authors: Liu Xiao , Wang Zi Ming , Liang Xu , Zhu Jie , Zhao Jue
Published: September 2013

The synthesis process of polycarboxylate superplasticizer (PCE) by bulk polymerization was investigated. Compared with BPO as initiator, PCE prepared by using AIBN as initiator exhibited better cement paste fluidities. PCE using isopentenyl polyethylene glycol (TPEG) or isobutenyl polyethylene glycol (IPEG) as macromonomer showed excellent fluidities and retaining properties at 80°C and 75°C, respectively. The fumaric acid was more suitable to copolymerize as the third monomer than maleic anhydride. The molecular weight measurements showed that the characteristics of molecular weight and its distribution for all the synthesized samples were in accordance with their cement paste fluidities. The solid-state PCEs can be conveniently dissolved into water to prepare PCE solution with arbitrary concentration, and still with good cement application performances.
Research on Static Compressive Experiment of Concrete Mixed with Limestone Power and Fly Ash
Authors: Liang Ji Feng , Lv Lei , Wang Feng
Published: September 2013

The use of orthogonal test method, the concrete mixed with limestone power and fly ash was carried out static compressive experiment, and contrast with the experiment of single doped with limestone powder and fly ash concrete. The experimental result demonstrated that the compressive strength enhancement effect of the concrete mixed with limestone power and fly ash was obvious. The importance of each factor affecting static compressive strength as follows: water-cement ratio, the amount of fly ash, the amount of limestone powder, sand ratio. The concrete compressive strength reached the maximum when the water-cement ratio reached 0.3, the limestone powder content reached 15%, the fly ash content reached 10%, and sand ratio reached 34%.
Development of Self-Cleaning Luminous PVC Flexible Composite Building Materials
Authors: Qi Meng , Shen Lan Ping , Wang Yong Ming , Zhou Xiao Rong
Published: September 2013

The nanosized TiO2 and luminescent materials were coated on PVC flexible composite material to get self-cleaning luminous PVC flexible composite building materials, the materials durable-polluted, luminous, reused properties and the adhesion property of the nanosized TiO2 and luminescent material particles were tested and studyed. The experimental results show that the nanosized TiO2 and luminescent materials finishing self-cleaning luminous PVC flexible composite building materials gain significant and good durability performance of self-cleaning and luminous functions.
Influence of Different Curing Days on Mechanical Properties of Concrete with Admixtures of Fly Ash, Blast Furnace Slag and Silica Fume
Authors: Kim Jeong Eun , Park Wan Shin , Kim Sun Woong , Kim Do Gyeum , Cho Myung Sug , Yun Hyun Do
Published: September 2013

High performance concrete (HPC) can be made with cement alone or any combination of cement and mineral components, such as, blast furnace slag, fly ash, silica fume, kaolin, rice husk ash, and fillers, such as limestone powder [. In this study, three mixes of high performance concrete (HPC) with same water-binder ratio and different types of mineral admixtures were prepared. he compressive strength, splitting tensile strength and modulus of elasticity values were measured in accordance with the ASTM. The influence of fly ash (FA), blast furnace slag (BS) and silica fume (SF) on mechanical properties of HPC were compared and analyzed. Their mechanical properties are measured at 7 days and 28 days. The results showed that specimen BS45+SF5 performed better than specimens BS30+FA25+SF5 and BS65+SF5 for the compressive strength, splitting tensile strength and modulus of elasticity.
Research on Esterification Technology of Polycarboxylate Superplasticizer and its Cement Paste Fluidities
Authors: Zhu Jie , Wang Zi Ming , Liu Xiao , Liang Xu , Li Hui Qun
Published: September 2013

The synthesis process of esterification products used for the preparation of polycarboxylate superplasticizier (PCE) was systematically investigated, and the influences of water dosage, the catalyst dosage, reaction time and inhibitor dosage on the esterification rate and cement paste fluidities were determined. The results showed that the esterification rate can reach more than 95% as the water-carrying agent of 70 g, catalyst-alcohol ratio of 0.07, reaction time of 7 hours, inhibitor-acrylic acid ratio of 0.03, respectively. The obtained esterification products subsequently copolymerized with macromonomer to prepare PCE, and then the application performances were tested by adding PCE to cement pastes. From the fluidity results, the cement paste fluidity and fluidity retention capacity of PCE were better than those of commercial PCE, and this was in accordance with the high esterification rate of its esterification rate.
A Review: Application of Nanomaterials in Concrete
Authors: Zhao Zhi Qin , Sun Ren Juan , Xin Gong Feng , Wei Shan Shan , Huang Da Wei
Published: September 2013

In this paper, the current situation of nanomaterials used in concrete were introduced, mechanism of nanomaterilas was reviewed. Recent application of nanomaterilas in special concrete such as air purified concrete, eco-concrete, high tenacity concrete were present.