bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Corrosion of Reinforced Concrete Structures by Chloridion in Port Engineering Construction
Authors: Dong Yan Ying , Zhang Li Shan , Zhang Ming , Zhu Tian Zhi
Published: September 2011

In port engineering construction, the source of chloridion is concrete raw materials, admixtures and the penetration of seawater. Chloridion makes rebar corrosion, and makes the expansion and crack of reinforcement concrete, leading to concrete structural damage. By selecting the right concrete raw material, appropriate admixtures and to ensure concrete construction quality, in order to effectively avoid chloridion to the damage of reinforced concrete structures in construction.
Numerical Simulation of the Water Entry of a Wedge Based on the Complex Variable Boundary Element Method
Authors: Gao Jie , Wang Yong Hu , Chen Ke An
Published: September 2011

The water entry problem of a wedge is simulated based on the velocity potential theory in time domain. The Complex Variable Boundary Element Method (CVBEM) is used in the stretched coordinate system. Before the simulation, the similarity solution is taken as the initial conditions. The auxiliary function scheme in conjunction with the same CVBEM is used to obtain the accurate time derivative of velocity potential and pressure distribution on wedge surface. The time marching solution is matched with the jet special treatment. Finally, the simulation results are compared with the similarity solution, which shows that the jet linear approximation can simulate the jet well.
Numerical Analysis of Ship Wave Loads and Structure Strengthen Analysis on a Wind Power Installation Ship
Authors: Li Gang Qiang , Zhao Yan Yan , Xie Yong He
Published: September 2011

In a typical load condition of wind power equipment Installation ship, using the three-dimensional potential flow theory to prediction the long-term response of wave induced loads. then using the main load control parameters as a basis for the design wave selection, then application of DNV's SESTRA program make the wave-induced directly to the structure to finite element simulation. The results show that the hull structural design can meet the requirements.
Parameters Selection of High Pressure Consolidation Grouting for Xiaowan Resisting Force Rockmass
Authors: Liu Fu Hai , Wang Jing
Published: September 2011

After substituting with ordinary Portland cement for geological defaults in resistance rock-masses of the dam abutments in Xiaowan hydroelectric station, it was necessary to make unsubstituted sections be reinforced by means of high pressure consolidation grouting. So it was before grouting and reinforcing that several productive experiments on high pressure consolidation grouting were carried out in the representatively and typically geological sections chosen in situ. Results indicated that desired effects for geological defaults in the dam abutments could be gotten after grouting when the distances to orifice and grouting pressures were 2m, 3m, 5~7m and 3.0MPa, 5.0MPa, 5.0MPa on the first section, the second one and the following ones of the orifice, respectively. And the grouting manners which were orifice enclosed and grout cycled in holes were adopted. Eventually, all of the grouting parameters could be used in much larger districts in projects to consolidate better.
Study on Proposed Value of Catanchor Coefficient for Large Prestressed Pier
Authors: Huang Zhen Ke , Fu Shao Jun , Qiu Huan Feng , Chen Sheng Hong
Published: September 2011

The Catanchor Coefficient Method is widely adopted because of its simplicity and convenience. However, how to determine the value of catanchor coefficient is still a problem. In this paper, four typical large prestressed piers were analyzed via Finite Element Method (FEM) and the relationship between the catanchor coefficient and the tensile stress occurring inside the controlling part was studied. The results we obtained indicate that the tensile stress decreases nonlinearly when the catanchor coefficient increases. Moreover, it changes quickly when the catanchor coefficient is within the range from 1.10 to 2.00 but slowly when that is from 2.00 to 3.00 in contrast. Based on our conclusions, the range from 1.50 to 2.00 of catanchor coefficient is advised with the data of related prestressed piers.
Analysis on Characteristics of the Rainfall-Runoff in Beizhangdian Watershed
Authors: Liang Rui , Zhu Qiao , Ren Huan Lian , Jin Hua
Published: September 2011

Beizhangdian watershed is a typical semi-dry and semi-humid region, where human activities have little effect on the hydrological cycle. Based on a 30-year hydrological observation data, the precipitation, runoff, and rainfall-runoff relationship were researched by the hydrology statistics analysis methods. The results indicated that the inter-annual change of rainfall-runoff of the watershed is remarkable, the annual distribution of rainfall-runoff is extremely uneven, and rainfall-runoff mainly occurred in flood season (June ~ September). There is a good uniformity between the variation tendency of annual rainfall and annual runoff in time and amount, the correlation coefficient of rainfall and runoff is 0.74, the value of the F-test is 4.23.
The Influence of near-Fault Ground Motions on the Seismic Response of Reinforced Concrete Frame
Authors: Zhang Chang Hao , Wang Wei , Wang Hu , Wang Xun Tao
Published: September 2011

This paper examined the engineering characteristics of the near-fault ground motion. The four-story reinforced concrete frame was designed under Code for seismic design of building (GB50011-2010).The SAP2000 software was applied to model it, and the nonlinear time history analyses of structure were implemented. Near-fault ground motions with forward directivity and fling-step and far field ground motions were selected as seismic inputs．The results show that in terms of some structural dynamic response parameters, such as the vertex displacement, between the corner of the layer displacement, and the base shear et al., the structural responses to the ground motion with near-fault are increased by considerable magnitudes when the seismic responses of structures step into the elastic-plastic stage, compared with far-field ground motion, and the influence of damaging the mid-lower structure is significantly greater.
Experimental Research on Interference of Marine Risers with Suppression Device
Authors: Li Peng , Guo Hai Yan , Li Xiao Min
Published: September 2011

An experimental research on interference of two risers with suppression device was conducted. The arrangement of the two risers is side-by-side, one is bare and another is a riser with triple strakes. Centre-to-centre distances from 3 to 10 diameters of the risers were studied. The riser model was a 18mm diameter organic glass with wall thickness of 2 mm. The current velocity ranges from 0.3 to 0.8 m/s, with approximate increments of 0.1 m/s. Dynamic strain records were obtained through the dynamic strain gauges which were sticked on the surface of the risers. The experimental data were contrastive studied by dynamic response, amplitude and frequency, respectively. The experimental results indicate that interference have little effect on the oscillatory characteristic of the riser with triple strakes while have important effect on the oscillatory characteristic of the bare riser with different distances.
Shear-Lag Effects in Three-Span Continuous Box Girder
Authors: Dong Yu Li , Fang Yuan Yuan , Lv Jun Li
Published: September 2011

The physical explanation of shear lag is given in this paper. The shear lag effects can be attributed to the abrupt change of shear stress at web-flange junction. The abrupt change at the junction of shear stresses changes the magnitude of the flange bending stresses, which attenuates gradually with increasing distances from the web. Meanwhile, the abrupt change of shear stresses from zero to the flange shear stress also influences the bending stress state at the centerline of the flange. The method to determine the shear lag effects has been given, which is based on the Euler-Bernoulli elementary theory of bending, and the calculated results are in good agreement with the experimental results. Considering the transversal distribution of the shear stress at the junction, the flange real bending stress could be calculated on the section. The change of the shear stresses decreases the magnitude of the bending stresses in tension, but increases the magnitude of the bending stresses in compression. The shear lag effects in continuous box girder are different from that in the simply supported box girder. The reaction force of the continuous support would generate an abrupt change of the shear forces between the two sides of the support, and the real bending stresses beside the support would vary significantly due to shear lag effects. The ratio of real bending stress to standard bending stress is not the proper index to reflect the shear lag effects, but the real bending stresses could represent the shear lag effects and should be paid more attention to in design.
The Space Model of Dynamic Analysis of Seated Large Diameter Cylinder Breakwater under Random Waves
Authors: Zhong Xiao Hong , Zhou Xi Reng , Sun Ke Li
Published: September 2011

According as three motion modes of motion process of the seated large diameter cylinder breakwater(LDCB) under random waves , the dynamic model system composed of spring-damper-antislider to control the lateral sliding is introduced, and corresponding dynamic analysis space model is established. The space model is realized by Parameter Design Language APDL of the large finite element software ANSYS. Calculated results by the space model comparing with those by the plane model respectively , some valuable conclusions are achieved. The validity of the model, which can be used in dynamic response analysis of the seated LDCB under random waves, is confirmed by the given example.
Experimental Study on Mechanism of Wave-Induced Silty Seabed Fluidization
Authors: Liu Hong Jun , Wang Hu , Zhang Min Sheng , Wang Xiu Hai
Published: September 2011

Abstract. In this study, process of wave-induced silty seabed response was explored in a rectangle flume. Based on the experimental phenomena, the variations of pore water pressure and theory analysis, discussions were made on the mechanism of wave-induced silty seabed instability. Results indicated that seabed under wave nodes would experience fluidization and oscillation under wave actions, obvious pore pressure accumulation was observed at the same time. The mode of wave-induced silty seabed instability was fluidization. The mechanism of wave-induced silty seabed fluidization was a combination of excess pore water pressure and shear failure, the chief factor of fluidization could be ascribed to wave-induced cycling shear stress. The steady state strength was somewhat an expression of the level of wave-induced decrease of soil strenth that could finally reach, therefore, it could be used for the estimation of wave-induced fluidization of silty seabed.
Effect of Sulfate Ion to Chloride Ion Transmission in Concrete under Flexural Load
Authors: Jin Zu Quan , Zhuang Qi Chang , Lin Jie
Published: September 2011

Chloride ion ingression into concrete under flexural load is investigated in the paper. Concrete specimens have been stored in 3.5%NaCl solution or 3.5%NaCl + 5%Na2SO4 solution for 210 days. The effect of flexural load and sulfate ion to chloride ion transmission is studied. The experimental results show that sulfate ion reduces chloride ion transmission in concrete. But when concrete under flexural load, Sulfate ion has plus and minus effect on chloride ion ingression into concrete. When the flexural load rate is low, sulfate ion reduces chloride ion transmission. But the flexural load is high, the negative effect of sulfate corrosion plays a main role. When concrete exposed to 3.5%NaCl+5%Na2SO4 solution, chloride ion diffusion coefficient of concrete in tensile zone increases with flexural load. And in compressive zone, the chloride diffusion coefficient decreases first and then raises with increasing flexural load.
Calculation and Analysis of the TBM Construction Rational Buried Depth
Authors: Ma Li Na , Yan Song Hong , Zhang Rong Ling
Published: September 2011

The sixth Chongqing metro line is taked for example, numerical simulation is applied for finite analysis and calculation, the safety of the primary support and the second lining are calculated respectively in different level of surrounding rock, double hole case,different bedrock and overlying abandon ballastless thickness for 45 cases,and then based on the result analysis and calculate the rational buried deepth of the surrounding rock under the different level, And according to the actual measurement of deformation calculation value and deformation value of hole is used for comparison, reference and basis for the similar case is presented.
A Method of Selecting Weight Iteration Based on LS-TLS
Authors: Kang Xiao Feng , Zhang Hua Ping
Published: September 2011

This paper introduces a theory of selecting weight iteration applied to line type identification, image recognition, etc. We deduce the method of Selecting Weight Iteration Based on LS-TLS which having remarkable advantage when both independent variable x and dependent variable y are containing errors gross errors. And we propose its common calculation procedures, carry on accuracy evaluation. At last, this method has proved its availability by a practical example.
Study on Capacity Bottlenecks Identification and Elimination of XiErQi Station in Beijing MTR Based on Simulation Method
Authors: Yu Dan Dan , Han Bao Ming , Li De Wei , Zhou Wei Teng
Published: September 2011

Due to the capacity limitation, congestions caused by the excessive amount of passenger flow appear in many Mass Transit Railway(MTR) hubs. Computer simulation is one of the most effective way to solve this problem. In this paper, an identification and elimination of capacity bottlenecks method was proposed based on dynamic movement of passengers simulation. Possible optimized solution was investigated through a case study in XiErqi Station, which is the transfer hub of Line13 and Changping Line in Beijing MTR. The proposed model was validated both statically and experimentally. Two optimization measures were dicussed after digging out the passenger feature and the essence of the congestions. One is improving passenger flow organization, the other is reforming operation organization. Then the simulate experiments were done through a proprietary software developed by Beijing Jiaotong University----SRail System. The simulation result shows congestion was alleviated effectively. It is proved that the method is feasible and effective.
Automatic Trigonometric Leveling System Based on GPS and ATR
Authors: Guo Jin Yun , Yu Lei , Liu Xin , Kong Qiao Li , Li Guo Wei
Published: September 2011

Trigonometric leveling method is often used to connect the height over sea. Error analysis of trigonometric leveling is made. In order to automatically achieve the trigonometric leveling over long distance, an automatic trigonometric leveling system is put forward with the combination of GPS and the automatic target recognition (ATR) techniques in this paper. The primary design of the system prototype including the structure and the software is given. The practical principle tests are also made to prove the system performance. The results indicate that the leveling precision of the system can satisfy the requirement of fourth order leveling.
Dewaterability of Aerobic Granular Sludge
Authors: Zhou Yan Nian , Li Jun , Li Jing , Wei Su
Published: September 2011

Dewatering characteristics of aerobic granular sludge, activated sludge and sludge which mixed flocculant was studied. It was shown that the specific resistance of aerobic granular sludge is lower than activated sludge and sludge with mixed flocculant was in the range of 1.07~1.80×109 S2/g, and it increased with the increase of diameters of the granules. The water ratio of aerobic granular sludge by pressure filtrate dehydration was decreased to 83.5~86.1%, activated sludge and sludge which mixed flocculant were 94.2% and 91.4%, respectively. The structural characteristics, distribution features of extracellular polymeric substances and PN/PS values of aerobic granular sludge were important factors of its excellent dewaterability. Aerobic granular sludge technology was regarded as one of the promising biotechnologies in sludge treatment.
Factors Influencing the Removal of COD from Coking Tail Wastewater in the Biological Aerated Filter
Authors: Liu Ji Ming , Yang Yun Long , Yang Xue
Published: September 2011

coking tail wastewater is difficult to dispose due to its hard-degradation substance. Biological Aerated Filter (BAF),with a characteristics of strong resistance to organic impact load,is a new way in treating high-concentration organic wastewater.In this paper, coking tail wastewater disposed in two-stage BAF is investigated. It shows that the optimized condition to dispose organic is that temperature is 25 ~ 35 °C, pH is7 ~8, gas-water ratio is 2~3:1, reflux ratio is 0.5~1. Under optimal conditions COD removal rate of the system remains stable around 69.10%.
Modeling of Headloss Development in Biological Aerated Filter (BAF) —Ⅰ. Equations Development
Authors: Liu Qiang , Qiu Li Ping , Chen Jing Ying , Guo Chun Hui
Published: September 2011

Biological Aerated Filter (BAF) has been global applied in secondary and tertiary wastewater treatment process in the past decades. As the increasing application of BAF, it was required to get deeper understanding of the operational discipline, parameter optimization and structural characteristics of BAF to improve the treatment efficiency and to operate stability constantly. In this paper, a physical filtration equation of clean filter bed was established firstly based on an average porosity ratio equation and Kozeny-Carman filtration equation. And then the influence of biological oxidation and biofilm development were introduced, of which the Eckenfelder mode and oxygen transfer were considered, to induce a hybrid physical- biologically equation to describe the headloss development in the BAF.
Constructed Wetlands for Wastewater Treatment in Mainland China: Two Decades of Experience
Authors: Zhai Jun , Qin Chuan , Xiao Hai Wen , He Qiang , Liu Jie
Published: September 2011

Constructed wetlands (CWs) have been applied for wastewater treatment since 1987 in Mainland China. There were about 150 public owned CWs operated to treat different types of wastewater, including urban domestic wastewater, rural sewage, effluent from secondary treatment, industrial wastewater, urban and agricultural runoff. About 44% of the CWs are designed for urban and rural sewage treatment. Hybrid CW takes a majority role for wastewater treatment in China. There are 24 full-scale hybrid CWs among the surveyed 59 systems in this paper. The most frequently used filtration media for vegetated beds are gravel and cobble. Phragmites australis is the dominate plant used in CWs in north China, while cyperus alternifolius and Typha latifolia are commonly applied in south China. The statistical average removal efficiencies of CWs for industrial wastewater treatment are the highest in terms of COD and BOD5, followed by the efficiencies of treating urban domestic wastewater, rural sewage, effluent from secondary treatment, urban and agricultural runoff in a decline order with a revise trend of the designed hydraulic loading rates.
Degradation of Refractory Wastewater by Chlorine Dioxide Oxidation
Authors: Fang Hua , Fu Xiao Ru , Xu De Fu , Wang Yuan , Lu Ji Lai
Published: September 2011

The ClO2 chemical oxidation system and ClO2 catalytic oxidation system are studied in this paper. The results show that pH=6~8, 1000mg ClO2/L wastewater, reacting 60min are the most efficient and economical, when treating Acid Brilliant Scarlet GR dyestuff wastewater, the COD of which is 3500mg/L, by ClO2 chemical oxidation. The COD removal ratio exceeds 50%, and the oxidation index (COD removal amount/ ClO2 used amount) is 2.3. When treating the wastewater by catalytic oxidation which is composed of ClO2 and special catalyst, pH≈2, 800mg ClO2/L wastewater, reacting 45~60min are the most efficient and economical. The COD removal ratio exceeds 80%, and the oxidation index (COD removal amount/ ClO2 used amount) is 3.5. The cost of oxidant removing 1kg COD is ¥3.7. The effect is superior to that of ClO2chemical oxidation apparently. The study indicates that ClO2 catalytic oxidation is an efficient method to treat refractory wastewater and it’ll have a broad prospect.
Study on the Adsorption of Reactive Black on Nature Diatomite
Authors: Gu Zhi Pan , Yang Xue Bin , Yang Ji Chun , He Shao Hua
Published: September 2011

The effect of masss of natural diatomite, initial dye concentrations, pH and temperature on adsorption was investigated. The adsorption of reactive dye was slightly increased then decreased with rising amouts of natural diatomite that is increasing competition of natural diatomite. The removal rate of reactive black increase with the temperature because of endothermic reaction. The removal rates of reactive black from solution were decreased as the pH increase and gain the maximum in low pH. The removal rate for all concentrations were rapid at initial stages and then keep increase gradually until the progress until equilibrium reached.
Method to Identify the Critical Slip Surface of Side Slope via the Deformation Field and Stress Field Calculated through Deformation Modulus Elastoplasticity Strength Reduction Method
Authors: Zhang Yu Cheng , Yang Guang Hua , Hu Hai Ying , Liu Peng
Published: September 2011

When strength reduction method is used for side slope analysis, only the intensive parameters are reduced and deformation parameters are not. The ideal elastoplastic model is adopted, and the safety factor is basically in agreement with that of the traditional limit equilibrium method. Main result is the safety factor of side slope, but non-linearity of soil is not considered actually during calculation, so it's hard to arrive at a real deformation field. Based on the deformation modulus elastoplasticity strength reduction method, research of this paper can achieve a more truthful deformation field. Considering the deficiencies in the current slip surface search techniques, this paper mainly studies how to determine the slip surface directly through the slope deformation field and stress field based on the analysis to their characteristics and the formation mechanism and characteristics of slip surface. Three methods to determine the slip surface are worked out: One is to use displacement gradient to identify the most disadvantageous slip surface; The second one is to determine the slip surface using the characteristics of FLAC calculation method and the characteristic that nodal velocity at non-slip area is near to zero and nodal velocity at slip area is very great; The last one is to use the deviation survey method in slope monitoring to track the nodal displacement in numerical analysis, and take the points with displacement catastrophe as those on the slip surface, and link those points to form a curve and finally get the critical slip surface. Analysis is made to the slip surface of clay slope with weak layer. Position of slip surface determined through these three methods is basically the same. Compared with traditional critical equilibrium method, these three methods can not only be applied to homogeneous side slope, but also be used to determine the slip surface of heterogeneous side slope. This paper makes a research on expansion of the application field of deformation modulus elastoplasticity strength reduction method.
The Effectiveness Analysis of Some Large-Scale Central Heat Supply System Energy Conservation Transformation
Authors: Hu Jian Jun , Sun Chun Hua , Qi Cheng Ying , Yang Hua , Zhao Zhi Ming
Published: September 2011

In heat source ability sufficient situation, some phenomenon occurred in some central heat supply system, such as uneven heating, serious disorders, the far-end heating reliability was insufficient. To improve the heating security and reliability, this article carries on an investigation test, problem analysis, Clears the crux of the problem, Proposes the corresponding transformation plan, and carries on the effective analysis of the actual heating effect after transformation. The results show that after transformation, the actual heating network runs well, increases the heating area, improves the heating security and reliability, provide the reference for other large-scale pipe network energy conservation transformation.
Process Simulations of the Cold Recovery Unit in a LNG CCHP System with Different Power Cycles
Authors: Sun Heng , Zhu Hong Mei , Liu Hong Wei
Published: September 2011

A CCHP system using LNG as the primary energy should integrate cold recovery unit to increase the total energy efficiency. A scheme of CCHP consisting of gas turbine-steam turbine combined cycle, absorption refrigeration unit, cold recovery unit and cooling media system is a system with high efficiency and operation flexibility. Three different power cycles using the cold energy of LNG is(are 或 were) presented and simulated. The results show that the cascade Rankine power cycle using ethylene and propane in the two cycles respectively has highest energy efficiency. However, the unit is most complex. The efficiency of ethylene Rankine power cycle is little lower than the cascade one, and is much higher than the traditional propane Rankine cycle. The complexity of ethylene cycle is identical to that of the propane cycle. The ethylene Rankine power cycle is the referred method of cold recovery in a CCHP system based on overall considerations.
Review on the Research of Indoor Environment Quality and Building Energy Consumption
Authors: Yang Xue Bin , Gu Zhi Pan , Yang Ji Chun , Lin Guang Ping
Published: September 2011

This study reviews some published literatures to survey the recent research on indoor environment quality and building energy consumption. The indoor environment quality is categorized and defined as different indices and variables. The building energy consumption can be determined by ventilation rates, thermal comfort, adaptive thermal comfort, neutral temperature, set-point temperature, indoor air quality, air velocity, and non-occupied hours. Various climates or regions such as subtropical climates in Hong Kong, Italy, three climatic zones in Greece, hot and dry climates in Africa, hot and humid climate in Thailand, are contained. The building types include office buildings, commercial buildings and school buildings, and the data can be obtained from a simulation model or the field database. It can be concluded that the indoor environment quality has a significant influence on the building energy consumption, and a validated thermal model is be a practical tool to investigate the effect of the indoor environmental parameters.
Experimental Study on Mechanism for Self-Weight Consolidation of the Red Mud Tailings Placed in the Karsts
Authors: Ou Xiao Duo , Yang Jian Wei , Yin Xian Tai , Liao You Fang
Published: September 2011

Four PVC pipes with the length of 1500 millimeters and inner diameter of 160 millimeters were used to make a consolidation device with a drainage system at the bottom, in order to make a study on the relationship between surface sedimentation and water discharge with time at different heights (the heights were adopted as 150 millimeters, 250 millimeters, 300 millimeters, 350 millimeters respectively) of red mud tailings of Pingguo Aluminum. A test was conducted on the mud discharge of the first layer and second layer respectively. It is shown that when the red mud is discharged at the first layer and the second layer, the sedimentation of which increases with the increase of height. The sedimentation curves of the first layer with 300mm, 350mm heights and the second layer emissions have two turning points. The red mud sedimentation rate of the height of 300mm is faster than the other three and the gap of the water discharge between heights of 250 millimeters and 300 millimeters is about 100 gram. The water discharge of the second layer is smaller than the first layer, of which the gap is about 250 gram; the decreasing rates of the red mud void ratio of the first layer and the second layer are the same, but the decreasing speed of void ratio of the first layer emissions is much faster, and the final void ratio tends to be between 1.22 ~ 1.26; The density curve experiences two processes of increase and two processes of decrease after the mud of first layer and second layer are discharged respectively, then tends to be stable and the stable value is between 2.01 and 2.06 g/cm3.
A Comparative Study of Seismic Performance Defined by Chinese Code and Eurocode8 on Seismic Design of Bridges
Authors: Lu Ben Yan , Wang Gang
Published: September 2011

Earthquake codes have been revised and updated in recent years. The issue and implementation of the guidelines for seismic design of bridges have attracted interests and attentions of many researchs at home and abroad. The most important aspect of the code rests on its main approach incorporating “performance-based seismic design”. The main purpose of this study is to investigate the differences caused by the use of guidelines for seismic design of highway bridges and Eurocode8 for bridges in performance criteria, seismic design categories, ground types, response spectrum, earthquake action and detailing of ductile piers. The differences in expressions and some important points for performance criteria, seismic design categories, ground types, response spectrum, earthquake action and detailing of ductile piers by codes are briefly illustrated in tables and figures. Based on the lessons learned from significant earthquakes in the last few years, the existing problems of the current code are pointed, and the trends of future study are discussed.
Visual Inspection and Detail Evaluation for Earthquake Disaster Mitigation
Authors: Wah Choo Kok , Zakaria Rozana Binti , Ramli Mohd Zamri Bin
Published: September 2011

Malaysia is considered as a very low seismic region country. However countries that border Malaysia such as Indonesia and Philippines are the two most seismically active countries with frequent earthquakes. The close proximity of these countries means that Malaysia is prone to risk of distance earthquakes. As such, anticipated problem associated with earthquakes must be dealt with. There is several problems expected need to be justified in this disaster phenomenon. Area of higher risk to be affected by earthquake need to be identified. To date, many building in Malaysia are not designed to withstand seismic load which means that they are susceptible to collapse in the event of earthquakes. School buildings contain large numbers of public user during most of the times. A sustainable approach of visual assessment and detailed analysis are needed to ensure the school building sustainability towards an earthquake threat. An ATC-21 evaluation and a finite element analysis were performed on a 4 storey standard school building in order to evaluate its performance should it be subjected to seismic waves. Results from the analysis were used to compare with the structures actual capacity and a potential improvement to the building can be identified. The assessment methods engaged no destructive in-situ test and the cost involved in the assessment are kept to a minimum. The final outcome of the study produces a guideline and database that served as a potential maintenance proposal and reference for engineering community in the future.
The Application of E Shaped Steel Bearing on the Simply Supported Beam Bridge
Authors: Kong Ling Jun , Chen Yan Bei , Liu Jun , Jiang Qi Bin
Published: September 2011

To study the application of E shaped steel bearing on the simply supported beam bridge, the Xinhua bridge is analyzed by the nonlinear time-history method and the Midas/Civil software, considering the interaction between pile and soil. The related data are obtained through two computational models. And the data are compared in this paper. The results show that the bending moments and shear forces of the bottom of the fixed pier are reduced, due to using the E shaped steel bearing at the fixed pier. The E shaped steel bearing dissipates the earthquake energy and reduces the earthquake response of the bridge.
Highway Slope Stability Analysis Based on Strength Decrease of the Subgrade
Authors: Pang Chuan Qin
Published: September 2011

In long-term operation process, highway subgrade is subjected to strength decrease easily，and the water environment around often causes the side slope side-slipping. In allusion to the common clay, massive indoor triaxial tests have been carried on, the relationship between the shear strength index and the water content, compactness of the compaction clay has been determined. Based on the above research, slope stability analysis software GEO-SLOPE is used, to analyze common earth fill subgrade, soft soil ground, mountainous area subgrade and earthquake area subgrade separately. The impact of subgrade strength decrease on the slope stability has been studied considering different subgrade filling height. The results indicate that no matter what kind of subgrade form, strength decrease of the subgrade causes highway slope safety coefficient to reduce, this especially obvious in the high subgrade condition. Partial jitter possibly happens when strength decrease of the subgrade achieves to above 80% of the common earth fill subgrade. The subgrade side-slipping possibly happens when strength decrease of the subgrade achieves to 50% of the soft soil subgrade. The subgrade safety coefficient decreases the most when the main performance is side-slipping jitter of the intersection between fills and digs of the mountainous area part-cut and part-fill subgrade. The subgrade jitter happens when the shear strength index decreases to 50% under the combination of strength decrease and seismic force of the earthquake area subgrade. The high subgrade and the maintenance management of the special road section should be strengthened to avoid the project disaster.
Research about Different Molding Methods’ Effect on the Resistance against Frost and Shrinkage of Cement Stabilized Gravel
Authors: Liu Hai Long , Cheng Pei Feng
Published: September 2011

Through the test research of the two different molding methods of vibration and static pressure, including the analysis of traditional heavy compaction and the new vibration compaction, we could see that the result of the vibration could satisfied the field construction. Analysis of mechanical property was 7d unconfined compressive strength, at the same dose of cement, the strength of vibration was higher than the static pressure method’s and it was more rational and effective for the field control of the construction. Evaluation of water stability was up to the 28d and 5 times freezing-thawing tests, and the resistance ability against frost of vibration was better than the static pressure method. So adopting the vibration method could improve the resistance performance against frost of the road in northeast region of freezing-thawing in spring. From the 7d dry shrinkage test we got that the adopting the vibration method the resistance performance of dry shrinkage was much better and could improve the resistance against shrinkage of the road.
Selection of Independent Proposals with Random Cash Flows and Limited Total Investment Capitals
Authors: Jiang Ya Fei
Published: September 2011

Data and parameters of the proposals being selected may be not assured. This uncertainty of data and parameters can be expressed as random variables. The paper is about how to use random decision criteria to select independent proposals where investment capitals available are limited and cash flows or parameters are random variables. The paper first simply introduces the decision criteria on random condition, and gives the common methods to get these values of decision criteria. Then the general model of independent proposals decision with limited capital under random condition, and the solutions of proposals selection are put forward. In the last section a numeric example is given to show how to use software to select independent proposals with random cash flows and limited total investment capital.
Dynamic Analysis of Frame Container Wharf Subjected to Multi-Support Excitation
Authors: Xia Ming Qiang , Jia Hong Yu , Zheng Shi Xiong
Published: September 2011

Detailed calculation of the dynamic displacement and dynamic internal force response of each structual member of wharf structure in the earthquake are conducted to structural response analysis of finite element numerical model in the Cuntan container wharf under multi-support excitations(MSE). The comparative analysis of results of calculation evaluates the characteristics of the whole dynamic force of the structure , validates and optimizes engineering design and accumulates design experience, simultaneously,in order to further master performance states of container wharf and the application of an advanced type wharf to other regions.
Economic and Environmental Assessment of Redmud as Aggregate in Cement Clinker Production
Authors: Hong Jing Min , Wang Ling , Hong Jing Lan
Published: September 2011

A cost combined life cycle assessment was carried out to estimate the economic and environmental impact of redmud as aggregate in cement production. Results showed that the raw materials, transport, electricity and coal had the highest contribution to overall cost, while coal production and direct emissions represented the dominant contribution to overall environment impact. Improving energy and raw material efficiency and minimizing raw materials transport distance are the efficient way to minimize overall environmental and economic impacts.
The Urban Barrier-Free Environment in an Aging Society
Authors: Han Yan Hua
Published: September 2011

Based on characteristic analysis of the aged people’s traveling and research for the development of the urban barrier-free traffic environments, the article analyses some factors of the barrier-free traffic environment, such as road barrier-free, vehicles barrier-free, information and communication barrier-free. In order to offer some good advice in the rapid development of Urban barrier-free environment.
Adaptability of Cornus Alba Seedling under Drought Stress in Highway Greening
Authors: Xu Wen Yuan , Sun Long , Mu Li Qiang
Published: September 2011

The drought resistance adaptation mechanism of highway greening plants was always the focal point which the researcher payed attention. This experiment took Cornus alba as the study object and examines its resistance to drought stress by using the potting and water control method. The researcher measured bond water content, water saturation deficit, relevant water content, relevant content of osmotic water, and osmotic potential when full turgor and turgor were both zero. Other water condition indexes also were analyzed systematically. Finally, a comprehensive evaluation on the drought resistance of Cornus alba by fuzzy mathematics’ anti-membership function was conducted. According to the experiment result, Cornus alba had the highest drought resistance at B-level treatment (soil water content: 53.60%), followed by D-level (soil water content: 29.90%) treatment. Cornus alba had strong endurance and resistance to drought stress. This study could provide a scientific basis for the future introduction of other urban greenbelt plants and the choice of excellent traits.
Numerical Analyses for Layered Foundation by Coupling Finite and Axis-Radiate Infinite Elements
Authors: Xie Hong Yang , Yang Huan , Yin Jin Quan
Published: September 2011

The model of the axis-radiate infinite element is developed for simulation of the infinite layered foundation underlain by a rigid base. Within the infinite element, the coordinate and displacement of any point are expressed by those of the nodes located on the artificial boundary, and concise mapping functions can easily express the attenuation character of the displacement field. By coupling finite and infinite elements, the elastic recovery capacity and radiation damping of the infinite layered foundation are simulated. In the numerical calculation, the infinite element mesh is performed only on the artificial boundary. Compared to FEM, the present approach needs less nodes and elements, and shows good accuracy and efficiency.
Research on Dynamic Impedance Function for Horizontal Vibration of Single Pile
Authors: He Fang Ding , Guo Guang Jun , Yang Yang
Published: September 2011

The horizontal vibration characteristic of the pile foundation is a key technology in dynamic design of foundation engineering. By researching on the horizontal harmonic loads in layered foundation, use horizontal vibration answers of buried foundation to deal with horizontal vibration impedance problems of pile tip. The transition matrix can be used to analyze the dynamic impedance function for horizontal vibration of pile foundation in layered foundation. And results in the paper is checked with traditional methods, which shows the both results fitting well.
Numerical Simulation of Stress Distribution in a Tilted Transversely Isotropic Rock Stratum
Authors: Lu Bo , Lu Yang , Ma Wei
Published: September 2011

Based on the project of Baihetan hydropower station, concerning the extensively developed columnar joints rock within the dam site area, the article carries out a study on the asymmetric characteristic of stress distribution in a tilted transversely isotropic rock stratum, at presence of inclined structural interfaces, which is subjected to a strip loading. Several theories related to stress distribution of tilted transversely isotropic rock are analyzed, a numerical simulation of rock stratum is subsequently conducted and graphics of stress distribution corresponding to different inclination angle of structural interfaces are obtained. Finally, the paper makes a comparison between the stress distribution procured by simulation and that of the analytical theory, and a conclusion on how inclined structural interfaces influence mechanical properties of transversely isotropic rock is generalized.
Study of Fast Drained Consolidation of Silt
Authors: Huang Qing He
Published: September 2011

The silt has the properties, such as low strength and slow drainage; so it is usually treated by precompression method. For short construction period and low cost , a new drained consolidation method-drainage consolidation due to excessive pore water pressure for silt is tested: fist, the sand is replaced in the surface of silt for horizontal drain; and then, the plastic drain boards is applied for vertical drain; finally, the excess pore water pressure is generated by surcharge loads and dynamic consolidation and the drainage consolidation is fast under the excess pore water pressure. The result of the settlement observation and acceptance test shows that the result of drainage consolidation due to excessive pore water pressure for silt soft soil is remarkable.
Study on Antiseismic Measures of Tailings Dam
Authors: Pan Jian Ping , Wang Sheng Yi , Xu Shui Tai
Published: September 2011

Tailings dam due to earthquake action may lead to severe slippage damage, and setting antiseismic measure is an effective method to prevent damage. Dynamic nonlinear finite element method is used in the efforts to analyze the earthquake reaction and the deformation characteristic. To reduce dam seismic deformation, the reinforcement effect of geotextiles, rock pressure and stone column is studied. Finally, a synthetically antiseismic measure that is composed of geotextiles-reinforced in sub-dam, rock pressure out of starter dam and densification foundation is proposed. It is found that the synthetically antiseismic measure produces better antiseismic effect, and offers a consult for the antiseismic design of tailings dam.
FLAC3D Numerical Simulation Study on Deformation of Subgrade Construction Process
Authors: Lu Ya Ni , Li Gai Wei
Published: September 2011

Numerical simulation analysis of the deformation characteristics in the construction process of subgrade are conducted. Based on the different filling unit weight and roadbed elastic modulus conditions, the main research is that vertical settlement of roadbed center and the horizontal lateral displacement of road slope toe change with the increase of the depth of filling. It is believed that the lightweight filling should be selected or the roadbed elastic modulus will be enhanced as much as possible under the condition that satisfies various standard, which can improve the settlement deformation of highway.
Comparative Analysis on Neutral Point Distribution in Rigid Pile Composite Foundation on Collapsible Loess in High Speed Railway
Authors: Wang Chang Dan , Su Hui , Zou Chun Hua
Published: September 2011

To research and analyze the neutral point distribution of rigid pile composite foundation on collapsible loess ground in high speed railway, the centrifuge model tests are used to imitate pile raft composite foundation and pile net composite foundation in different pile spacing based on the experimental study at home and abroad. The research results show that the movement of negative skin friction and the position of neutral point which is drop conspicuously with larger pile spacing are a continuous changing process in composite foundation. In the pile spacing 2D,4D,6D of pile raft composite foundation, the stable range of neutral point position are 0.25(the pile length ratio), 0.59,0.63 separately in post-construction stage. In the pile spacing 2D(no pile-cap),4D(no pile-cap),4D(pile-cap),6D(pile-cap) of pile net composite foundation, the stable range of neutral point position are 0.37to0.43(the pile length ratio),0.50,0.80,0.81separately in post-construction stage. The pile-cap setting has more influence on Neutral point distribution. Suggestions are given that the waterproof and drainage measures in foundation must be considered when setting up composite foundation on collapsible loess.
Rectification Treatment of Digging and Watering along Horizontal Direction for Resident Building
Authors: Chen Qi Hui , Ping Yang
Published: September 2011

According to character of resident building and engineering geological condition, method of digging and watering along horizontal direction is put forward, and used for building’s rectification. Namely soil of horizontal hole is digged under one-floor ground and watered in superior subsidence side. Then subsidence is come into existence, and subsidence speed is controlled, the inclined building is forced to reverse step by step. Combining engineering examples, influence factors of building’s rectification are analyzed by numerical simulation method, which includes hole spacing, hole diameter and hole depth, and influence law of relative settlement is obtained.
Exploration and Practice on Remote Monitoring & Management of Excavation Engineering
Authors: Liu Jun Yan , Liu Yan , Liu Tao
Published: September 2011

A well-established management system and its corresponding carrier are urgently needed to make engineering construction management achieve such purposes as controlling investment, guaranteeing quality, ensuring safety and shortening construction period. Based on the analysis on the weaknesses of the traditional management model of excavation engineering, the paper introduces the composition and functions of remote monitoring and management system and put forwards with a new model of construction management. Project cases have proven that the management model can improve construction management level and be used by other project management for reference.