bluuebunny/crossref_metadata_2025 huggingface dataset:
Finite Element Analysis and Experimental Study on the Behavior of Widened Beam Flange Connections of Steel Frame under Cyclic Loading
Authors: Mao Hui , Wang Yan , Li Cheng Hua
Published: May 2011

Based on the experiments of four connections with widened beam flange section which included two arc widened beam flange connections and two welded side-plate connections specimens and one ordinary connection under cyclic loading, 3-D nonlinear finite element models were created by using ANSYS software to analyze the mechanical properties of these two types of widened beam flange connections, such as skeleton curve, ultimate load, ductility and failure mode etc. The analytical results show good agreement with those of the experiments and prove the finite models correct and applicable. According to the experimental and element analytical failure results, the PI(PEEQ Index) was introduced to investigate the plasticity development and fracture tendency at the end of the widened flange part . Furthermore, the failure patterns of widened beam flange connection were revealed.
Effect of Aggregate on Cracking Behaviours of Concrete in Mesoscopic Modeling
Authors: Sun Tao Yuan Zheng , Chen Shui Fu , Hu Le Sheng
Published: May 2011

This paper aims to study the influence of aggregate shape and size on the tensile strength, compressive strength and fracture energy in mesoscopic modeling of concrete. For this purpose, several numerical models under three loading cases, uniaxial tension, uniaxial compression and bending resistance test are analyzed utilizing the software ABAQUS/Explicit. The mechanical responses and cracking behaviors well match the realistic situations of experiments. Various stress-strain curves and fracture patterns are presented and compared, which indicate that the aggregate size has very small effect on the tensile strength, compressive strength and fracture energy, and the effect of aggregate shape is a little more significant than that of the size.
Parametric Numerical Simulation of Mean Wind Loading on Stadium Cantilevered Roofs
Authors: Sun Ying , Xiang Bo , Lin Bin , Wu Yue
Published: May 2011

Studies on the characteristics of the mean wind load acting on the cantilevered roofs are carried out systematically by CFD (Computational Fluid Dynamics) numerical simulation. The influences of some factors, including the incoming flow condition, inclination angle of roofs and the ventilation rate above grandstand, on mean wind loading are investigated. It is found that the terrain type and grandstand type are not significantly influence the mean wind loads on the roof structure; The wind force acting on roof is increased with roof pitch; Sub-roof venting is found to reduce uplifts by no more than 12%; Introducing a similar shaped grandstand upstream is found to significantly decrease the wind loading. Based on these results, an empirical equation for the calculation of mean wind loading is derived for the reference of designers.
Evaluation Indexes System for Assessing Road Construction with Recycled Waste Materials to Achieve Better Environmental Impacts
Authors: Chen De Zhen , Geng Cui Jie , Sun Wen Zhou
Published: May 2011

Evaluation indexes system has been put forward in this paper for quantifying thesystematical energy consumption, resources consumption, total emissions’ change and waste disposal capacity in road construction with recycled waste materials involved. With help of this evaluation indexes system, the contributions to environmental improvement caused by recycling waste materials in road construction can be quantified through calculating savings on environmental impact potentials, savings on energy consumption, on virgin materials’ consumption and waste disposal capacity provided by road construction. Based on the construction project of a road section numbered No.20 EWK0+400 ~ EWK0+600 of North highway to Shanghai Pudong international airport, which was the first trial project of using several kinds of recycled waste materials including bottom ash from incinerators to replace commonly used materials such as gravel in large scale in road pavement, the results of the four indexes, namely, savings on energy consumption and virgin materials’ consumption, environmental impact potentials as well as waste disposal capacity were obtained. It was found out that with multi recycled waste materials replacing part of the common construction material, systematical energy consumption can be reduced by 30%, a large amount of virgin resource consumption can be avoid and road construction also provides a remarkable large “dumping site” for solid wastes; while at the same time environmental impact potentials were saved for most impact categories except for increase in Ecotoxicity, water chronic, which was caused by heavy metals’ leaching and can be prevented by pre-treatment. Those results are useful for guiding the utilization of recycled waste materials, as well as for developing new technology process and advanced materials in road construction.
Applying Research on Microwave Promoting Curdle of Cement Concrete Appending UNF-5 Water-Reducing Agent
Authors: Wang Zheng Jun , Jin Xiao Ou , Sun Dian Min
Published: May 2011

In order to shorten time-periodic of mix design and verification of cement concrete in the period of construction, and can realize the node control of key procedure of cement concrete structure. The paper obtained and established relationship between super-early-stage strength and compressive strength of 7d, 14d and 28d of cement concrete on based of microwave promoting curdle. The method can realize predication of cement concrete through microwave promoting curdle.
The Stone Chips and Using in PHC Pipe Piles
Authors: Jiang Yuan Hai
Published: May 2011

This paper describes the preparation of the high-strength concrete with stone chips and the application of the stone chips in PHC pipe piles production. The results show that when the stone chips substitutes for the natural sand, the strength of the concrete increases and the workability of the fresh concrete is improved.
Analysis of Testing Methods for Volume Stability Evaluation of Steel Slag Sand
Authors: Lun Yun Xia , Liu Shao Shun , Zhou Ming Kai , Liu Xiao Fan
Published: May 2011

Many testing methods are used to evaluate the volume stability of steel slag sand, but none of them can legalized widely, which hinders its extensive use. Three typical methods-chemical analysis method, steam powdering ratio and mortar bar linear expansion rate under hot-water curing condition are compared in this investigation. The results showed that though chemical analysis method could rapidly judge the volume stability, the content of free CaO and MgO wasn’t precise because of the interference of calcium hydroxide and magnesium hydroxide in aging steel slag sand; the maximum powdering ratio reflected the uneven distribution of expansion components ; mortar bar expansion rate visually presented the volume stability of steel slag sand when used in mortar or concrete. So it was a synthetic application in order to decide the volume stability of steel slag sand.
Precast Lightweight Foamed Concrete Sandwich Panel (PLFP) Tested under Axial Load: Preliminary Results
Authors: Mohamad Noridah , Omar Wahid , Abdullah Redzuan
Published: May 2011

A study is carried out to develop a Precast Lightweight Foamed Concrete Sandwich Panel, PLFP, as a new and affordable building system. Experimental investigation to study the behaviour of the panel under axial load is undertaken. The panel consists of two lightweight foamed concrete wythes and a polystyrene insulation layer in between the wythes. The concrete panels are reinforced with 9mm diameter high tensile steel bars. The rebars are tied to each other through the insulation layer by shear connectors which are made of 6mm mild steel bars bent to 45º angle. Total number of four specimens was tested with one specimen; PA1 was cast without capping at both ends. It was used as a pilot test. The other three specimens are capped with normal concrete at both ends to avoid end crushing during axial loading. Axial load test was conducted and the results are presented here, which include the ultimate load capacity, crack pattern and failure mode, strain distribution and load-deflection curve of the panels. The experimental ultimate strength achieved recorded lesser percentage difference with the formulae by Pillai and Parthasarathy when compared to formulae in BS8110. It is also observed that the strength of the panels are affected by the compressive strength of the foamed concrete forming the wythes, the presence of concrete capping at panel’s ends and the slenderness ratio, H/t. Specimens with capping at both ends recorded higher ultimate loads with no premature crushing. Failure of panels with slenderness ratio, H/t < 18 were by premature buckling near the supports whereas for panels with higher H/t ratio, slight bending was observed in the middle zone. The results also indicate that a certain degree of compositeness is achieved between the wythes.
Quality Monitoring for Waterproof and Drainage of Loess Road Tunnel
Authors: Lai Jin Xing , Sun Jia , Liu Chi
Published: May 2011

Based on practice road tunnel engineering in Gansu province and near areas in west china, the main construction technology and emphasis of quality monitoring of waterproof and drainage of loess road tunnel are analyzed. Requirements of waterproof and drainage construction and methods of quality monitoring are obtained. Principle of design for waterproof and drainage in highway tunnels construction is provided. The analysis results provide technical guidance for the waterproof construction optimization of loess tunnels.
Field Test and Analysis on Impact Factor Spectrum for a Continuous Bridge under Random Traffic Flow
Authors: Han Wan Shui , Wang Tao , Yuan Su Jing
Published: May 2011

Field test and analysis were carried out for dynamic responses on a continuous bridge under open traffic. The inspection, testing and analysis for the tested bridge mainly consist of the measurement of pavement roughness and analysis on power spectral density, the testing and analysis on natural vibration characteristics, the observation of traffic loads under open traffic and the corresponding measurements of dynamic displacement and acceleration on bridge. To determine impact factors in terms of measured dynamic displacement responses, low pass Butterworth filter is used for filtering the dynamic part of measured dynamic displacement and the static extreme values are reserved. Finally, the relationship between impact factors and vehicle weight, vehicle speed is studied. It was found that impact factor tends to decrease with increasing vehicle weight, and integrally speaking, the impact factor increases gradually as the vehicle speed is increased within a wide range.
Behaviour of Composite Beam with Trapezoid Web Profiled Steel Section in Sub-Assemblage Frame
Authors: Anis Saggaff , Tahir M.Md. , Sulaiman Arizu , Shek Poi Ngian , Tan Cher Siang , Kueh Ahmad Beng Hong
Published: May 2011

The objective of this paper is to present the behaviour of composite beam using Trapezoid Web Profiled (TWP) steel section by determining the moment resistance and the deflection of the beam with composite and non-composite connections. The TWP steel section is a built up section where the flange is of S355 steel section and the corrugated web of S275 steel section. Three full scales testing setting-up as sub-assemblage frame have been carried out. It was concluded that the use of composite connection and extended end-plate has reduced significantly the deflection and has significantly increased the loading capacity of composite beam.
Prediction Model for Cementing Efficiency of Fly Ash Concrete by Statistical Analyses
Authors: Cho Hong Bum , Jee Nam Yong
Published: May 2011

This paper offers the model that can estimate the cementing efficiency of fly ash (k value) based on a mix proportion of concrete containing fly ash (FA). The prediction model was derived using various statistical analyses, based on a wide range of mix proportions and a number of strength test results of ready mixed concretes used in eight construction sites. The k value increases with increasing water-binder ratio. As the FA replacement ratios increase, the k value increases at FA replacement ratios of less than 15%, but decreases at ratios of 15% or more. The k values obtained from the cementing efficiency estimate model range from 0.1 to 2.1.
Is Gypsum External Rendering Possible? The Use of Gypsum Mortar for Rendering Historic Façades of Valencia's City Centre
Authors: Mileto Camilla , Vegas Fernando , La Spina Vincenzina
Published: May 2011

Valencia is a city located in the East of Spain by the Mediterranean Sea. It has a huge historic centre with ancient winding streets that contains buildings with a singular architectural heritage. The buildings’ façades are protected by a traditional external rendering, sometimes in bad state of conservation or modified or substituted in restoration works. The study carried out on historic renderings in Valencia points out the great employment of gypsum mortar or gypsum-lime mortar, among other peculiarities. Gypsum external rendering is one of the many uses for gypsum mortars in Valencia traditional architecture. This fact contradicts the general belief of the exclusive use of lime mortars for rendering a façade. The knowledge of the characteristics of historic mortars will allow us to implement a proper restoration work of architectural heritage with suitable mortars, as it is essential to guarantee the adherence and compatibility of any repair.
Solubility of Phosphogypsum in Pure Water and Lime Solution
Authors: Yang Min
Published: May 2011

In this work, the solubility of phosphogypsum(PG) in water and saturated lime solution was determined in experiments carried out at different temperatures from 10 to 50°C. The solubility of natural gypsum(NG) was also studied at an attempt to find out differences in solubility between PG and NG due to the effect of impurities. The results show that in pure water media, PG dissolves more rapidly than NG at early time, and then equally with NG. With increasing the temperature of water, the dissolution rates PG decreased while that of NG increased. In saturated lime solution, compared with NG, the solubility of PG was distinctly influenced due to the existence of impurities. Possible reaction among soluble impurities and calcium ion retarded the dissolution of calcium sulfate dihydrate.
Effect of Steel-Concrete Interface on Reinforcement Corrosion in Marine Environment
Authors: Zhang Rui Jin
Published: May 2011

This paper dealt with the influence of the steel-concrete interface quality and environmental conditions on reinforcement corrosion. High size concrete members were cast to get different interface quality decreased with the height of rebar due to the top-bar effect. Five groups of specimen with two concrete covers have subjected to different exposed programs. The experimental results showed that the concrete cover significantly influenced corrosion initiation and corrosion rate by blocking the penetration of aggressive agents. The height of rebar affected the corrosion initiation because of the variation of concrete porosity, interface defects and chloride threshold. The existence of defects at the interface was more important than the size of defect for corrosion initiation.
Dynamic Numerical Simulation for the Problem of Tunnel Rock Mass Large Deformation of a Hydropower Project in the Upper Reaches of Lancang River
Authors: Li Yu Sheng , Cao Guang Peng , Bao Jie
Published: May 2011

It is a very effective technology methods that using dynamic numerical simulation of discrete element method to study the large deformation problems of underground engineering rock mass which in the complex rock mass mechanics environmental conditions.Research achievements show that the development of deformation failure of the tunnel surrounding rock and the final convergence stability are mainly controlled by rock mass structure and its stress environment in the special toppling deformation rock mass. Deformation of the rock mass that in the lateral unloading and relaxation and also has a complex rock mass structure developed sustainably and progressivity over time,will eventually seriously damaged in roof fall. The surrounding rock deformation of the tunnel ,which have a good rock mass integrity and do not have the obvious unloading and relaxation stress environment, gradually tended to be stable after the initial deceleration-type development.
Survey on Factors Affecting Impermeability of Waterproof Concrete
Authors: Li Yi Jin , Gong Yun Li , Yin Jian
Published: May 2011

This paper describes the influence of raw material, water-cement ratio, sand ratio, cement-sand ratio and fly ash content on impermeability of waterproof concrete. The value ranges of several important mix parameters are summarized, that provides the reference to select the parameters of mix proportion of waterproof concrete for subway.
Finite Element Numerical Simulation Analysis on Strengthening High Gravity Abutment Using Carbon Fiber Sheet
Authors: Wang Zong Lin , Qin Li Hui
Published: May 2011

Gravity abutment widely uses for substructure part of the bridge structure. For many reasons, there are many damages take place in the parts of abutment. The objective of this study is to evaluate the strengthening effects on the performance of highly structure of Gravity abutment. ANSYS ver.10 software is used in the theoretical analysis of capacity of abutment structure .There are two experimental models. The first model uses one ring of carbon fiber sheet and the second uses two rings of carbon fiber sheet .The results of theoretical analysis show that there are good effects when using carbon fiber sheet strengthening method.
Evaluation for Dynamic Performance of Simple-Continuous Bridge
Authors: Sheng Ke Jian , Wang Zong Lin
Published: May 2011

It is necessary to study the dynamic responses of simple-continuous bridges under traveling vehicles action, which may benefit the improvement of their dynamic performances. According to “Standard Design Drawings” issued by Ministry of Communications of PRC, this paper considers the alterations of span length, decking width and sectional style and the differences of vehicle model and traveling speed, and calculates separately dynamic response of these structures with the “vehicle-bridge coupled vibration program”. As two key influential factors, vibration amplitude and acceleration are applied for the evaluation of structural dynamic performance. The results show that dynamic performance of simple-continuous cored slab bridge is deficiency in some degree.
Study on Stability of Explicit Finite Element Method for Wave Motion of Fluid-Saturated Porous Media
Authors: Li Liang , Du Xiu Li , Li Li Yun , Zhai Wei
Published: May 2011

In this paper, the stability of an explicit finite element method for wave motion of fluid-saturated porous media is studied based on the transfer matrix of calculating formula of the method. Transfer factor is defined to describe the stability of the method. The effect of time step, space interval and the value of permeability coefficient on stability is analyzed and practical stability criterion is presented. Research results show that with the increase of time step, the stability of the method will be deteriorated; with the increase of space interval, the stability of the method will be enhanced; with the increase of the value of permeability coefficient, the stability of the method will be enhanced.
Wave Induced Hydraulic Pressure by Wave Conditions of Pontoon Typed Floating Structures
Authors: Jeong Youn Ju , You Young Jun , Hwang Yoon Koog
Published: May 2011

In this study, in order to verify wave induced buoyancy effects by wave conditions of wave height and period, experimental studies were conducted to the floating structures of pontoon type. A series of small-scale tests with various wave cases were performed to the pontoon models. Two small-scale pontoon models having different bottom details were fabricated and tested under the five different wave cases. Six hydraulic pressure gauges were attached on the bottom of pontoon models and wave induced hydraulic pressure was measured during the tests. Finally, hydraulic pressure subjected to the bottom of pontoon models were compared with each other. As the results of this study, it was found that wave induced hydraulic pressures at bottom were dependent on the wave period as well as wave height, and waffled bottom shape hardly influenced on wave induced hydraulic pressure.
Field Test Study of the Blast-Resistance Performance of Optimal Composite Anchorage Structure
Authors: Zhao Lin , Zeng Xian Ming , Li Shi Min , Lin Da Lu
Published: May 2011

This paper introduced the comparison test of new optimal composite anchorage structure and single anchorage structure. The measured results show that the particle acceleration of single anchorage structure is 2.22 times higher than that of the optimal composite anchorage structure. The dynamic strain of the former is 5.3~4.5 times higher than that of the latter. The blast-resistance of the optimal composite anchorage structure is 5.10 times higher than that of the single anchorage structure. Under the limit damage condition, the former is 4.13~3.40 higher than that of the latter. The optimal composite anchorage structure has excellent blast-resistance. Optimal weakened zone is between the reinforced support structure and the surround rock. Under the explosion condition, weakened zone is firstly deformed, cracked, crushed or densified, and at the same time, a great deal of blast energy is absorbed. Therefore, the crisis of the reinforced support structure is transferred into the weakened zone.
Experimental Research on Flexural Behavior of FRP-Reinforced Concrete Beams
Authors: Sun Zhi Juan , Chen Chao He , Chu Ming Jin , Feng Peng
Published: May 2011

In order to improve the durability of reinforced concrete member, fiber reinforced polymer (FRP)-reinforced concrete member is introduces. Monotonic loading was applied to a reinforced concrete beam and FRP-reinforced concrete beam, in order to investigate the failure progress and characteristics of FRP-reinforced concrete beam.. The presenting study provide a basis for improving the design method for FRP-reinforced concrete member.
Numerical Simulation of Land Subsidence Caused by High-Rise Building, Applied in Tanggu, China
Authors: Ma Feng Shan , Wei Ai Hua , Ding De Min , Guo Jie
Published: May 2011

Ground subsidence is aggravated and becomes a prominent phenomenon recently in Tanggu, China. The subsidence reached its most critic state because of intensive water over-extraction in 1980s. Thereafter, over-draft withdraw of groundwater has been strictly controlled. Consequently, the rate of settlement decreased in the subsequent period. However, in recent year, ground subsidence becomes a prominent hazard again in some high-rise building areas .GPS-based monitoring data indicated new cone of depression has been formed. After detail investigation and analysis, it was thought that the appearance of the new subsidence center is the direct consequence of the construction of high-rise building. In this study, based on acquired monitoring data of subsidence, a special software package of Adina computer programs was applied in this study and analysis of the mechanism of subsidence induced by buildings. The results indicate that this method is useful to manage the land subsidence problem to high-rise building group.
Analysis on the Karst Foundation Collapse Caused by Groundwater Flow
Authors: Liu Zhi Kui , Zhao Bin Jie , Gu Zhan Fei , Mu Chun Mei , Liu Bao Chen
Published: May 2011

By the traditional calculation method of evaluating the stability of the karst foundation, the results often exist certain differences from actual engineering situation. Based on the hydrodynamics theories and the engineering case, a model of karst groundwater flow is established, the groundwater hydrodynamic force and the ability of carrying particles in sandy foundation of karst areas are calculated, and the karst foundation stability is evaluated in this paper.
Calculation of Unlimited Passive Earth Pressure in the Model of RBT Movement
Authors: Yang Tai Hua , He Huai Jian
Published: May 2011

Assuming the internal friction angle of backfill and the displacement are in nonlinear, to adopt the calculation model that was put forward by the author, combined with the in-room model experiment, to calculate and analyze the passive earth pressure acted on the retaining wall in the model of RBT movement. The analysis results show: the calculated values and the test values can agree with each other very well in the three ways of the distribution of earth pressure along the wall height, the values of the passive total force and its action point position. So it is feasible to use the calculation model to calculate the passive earth pressure in the model of RBT movement. Comparatively, when n = 0 the calculated values are the most identical with the test values, when n = 0.25 are worse, when n = 0.5 are the worst. Those may be relative to the sizes effect of the box of model test and the property of the interface between the soil and the plate at the bottom of model box. In addition, with the value of n increasing gradually, the maximum displacement needed to reach Rankine’s passive limit state will be decreased.
Experimental Research on Relationship of Load and Displacement of Universal Testing Machine
Authors: Xu Jiang , Lu Li Feng , Yang Hong Wei , Wang Jin Neng , Zhang Yuan
Published: May 2011

The related components of material testing machine (e.g., pressure plate, pressure head, compression bar, etc.) produce distortion in the experiment. It is obviously irrational to use the stroke to replace the specimen displacement, which can’t be measured directly by the extensometer in the destructive test. Therefore, the evolution of specimen displacement, machine displacement and stroke of 45 steel, duralumin alloy and sandstone was analyzed under uniaxial monotonic loading and uniaxial cyclic loading. The results show that the deformation of the related components of universal testing machine, which increases/decreases along with the increase/ decrease of load, can’t be ignored. And there is a good one-to-one correspondence between the machine displacement and the load. It also has nothing to do with the types of specimen materials and the experiments. The relationship of machine displacement and the load can be used to determine the specimen displacement indirectly.
Experimental Study on the Torsional Behavior of RC Composite Core Walls with Steel Tube-Reinforced Concrete Columns and Concealed Steel Trusses Subjected to the Combined Action of Multi-Directional Stresses
Authors: Dong Hong Ying , Cao Wan Lin , Zhang Jian Wei
Published: May 2011

An experimental study on the torsional behavior of two 1/6 scale core walls: one reinforced concrete core wall with concealed steel trusses and steel tube-reinforced concrete columns, and one normal reinforced concrete core wall, was carried out under eccentric horizontal cyclic loading. The torsional load-bearing capacity, torsional angle ductility, torsional hysteresis characteristics, torsional stiffness and its deterioration process, torsional energy dissipation and damage characteristics of the two specimens are herein discussed. Results show that the torsional performance of RC core walls can be improved by embedding the concealed steel trusses in the walls and setting the steel tube-reinforced concrete columns as boundary-columns.
Evaluation on Effects of Strengthening High Gravity Abutment Using Carbon Fiber Sheet
Authors: Wang Zong Lin , Qin Li Hui
Published: May 2011

Gravity abutment widely uses for substructure part of the bridge structure. For many reasons, there are many damages take place in the parts of abutment. The objective of this study is to evaluate the strengthening effects on the performance of highly structure of Gravity abutment. The results of damage inspection show that these damages are very serious in the direction of height and width of the abutment structure. Therefore, there is need to strengthen the abutment structure to improve the carrying capacity. There are two experimental models. The first model uses one ring of carbon fiber sheet and the second uses two rings of carbon fiber sheet .The results of experimental show that there are good effects when using carbon fiber sheet strengthening method.
Experimental Investigation on Fire Resistance of CES Columns Subjected to 3-Side Heating
Authors: Mao Xiao Yong , Guo Wei Hua , Li Li Li
Published: May 2011

Results of experimental study on fire resistance of four concrete encased steel (CES) columns are presented. The four columns have the same steel section and reinforcements but different load intensity and load eccentricity, which were the key factors for fire resistance of CES columns under fire condition. The tested results are utilized to study the effect of various parameters on thermal and structural response of CES columns. Spalling of CES columns under fire condition are also investigated. Test results show that CES columns under 3-side heating have higher fire resistance than that under 4-side heating. Also, load ratio and load eccentricity have noticeable influence on the fire resistance of CES columns. In addition, spalling of concrete decreases the fire resistance of CES columns.
Amount of Leachate Generated Factors and Control Measures
Authors: Li Ying , Guo Ai Jun
Published: May 2011

The influencing factors of landfill leachate are analyzed. This paper introduced the common computational methods for quantity of leachate generation, and put forward some measures and methods to control quantity of leachate generation.
The Stability Analysis on Reservoir Bank Slope of Granite Stained Subgrade
Authors: Wang Li Chao , Zhou Ping Gen
Published: May 2011

The limit equilibrium method for rigid body is used to analyze the stability of subgrade reservoir bank slope of granite stained. The sliding of subgrade reservoir bank slope reinforced by dynamic compaction along the interface will not be happened. In the most unfavorable conditions , the sliding surface will be formed inside the stained subgrade, which threatened to the safety operation of the expressway.
Seismic Analysis of Immersed Tube Tunnel for Hong Kong-Zhu Hai-Macao Bridge Project
Authors: Hu Xiao Yong , Zhang Xiao Xu , Qiu Yu Liang , Dong Wei Hua , Kou Bao Wen
Published: May 2011

A simplified seismic calculation model of immersed tunnel is built up, which is applied to the seismic analysis of Hong Kong-Zhu Hai-Macao Bridge Project’s immersed tube tunnel. According to different spring stiffness of foundation and different spring stiffness of joint, the tunnel and joint’s force and deformation conditions are compared. The results show that: the influence of foundation spring stiffness is significant, for engineering design, the foundations of a more flexible approach should be preferred; contrary to joint force, the joint opening increases with the increase of joint stiffness, thus, flexible joint is better for project; the connection parts of floor and wall, the connection parts of roof and wall are the most disadvantageous position during the earthquake, so, these parts’ design strength should be strengthened and deformation control should be taken.
Groundwater Dynamics Analysis of Sanmashan Side Slope in the Three Gorges Reservoir Region, China
Authors: Wang Jin Guo , Zhou Zhi Fang
Published: May 2011

Sanmashan side slope in the Three Gorges reservoir region is located in the center area of the Xincheng district, Fengjie county, China. Based on the analysis of hydrogeological structure of the studied area, one can conclude that a groundwater reservoir form near the side slope area after the impoundment of the Three Gorges Reservoir, which induces large groundwater pressure on the side slope. In particular, large hydrodynamic pressure will occur in the landslide mass under the condition of the reservoir water level descending significantly, which has bad effects on slope stability. Numerical simulation results show that the seepage force on landslide is 43 times of that under normal situation, as the reservoir water level declining dramatically from 175m to 145m. Thus, the influence of hydrodynamic pressure should be considered in the stability calculation.
Properties of Phosphate Cement Mortar Used as Rapid-Repair Material
Authors: Deng Hong Wei , Yang Ying Zi , Gao Xiao Jian
Published: May 2011

In order to determine the optimal proportion of magnesium phosphate cement mortar, the influences of ratio of magnesium phosphate cement-based binder (MPB) to sand (MPB/S), effects of fly ash on fluidity and strength development of MPB mortar, and the compatibility between MPB and traditional concrete and shrinkage of MPB mortar were investigated in this paper. The optimal proportion in this test was: setting adjusting agent of 12%, P/M ratio of 1:2(in weight), MPB/S ratio of 1:1 and FA/S ratio of 15%. The results showed that the MPB mortar met the higher early strength requirement of rapid-repair materials, with compressive strength beyond 50MPa and flexural strength more than 9.1MPa at 3 hours, and at later ages no reduction of strength happened. There was a good compatibility between MPB and traditional concrete. The shrinkage of MPB mortar at 28 days was less than 2.89 × 10-4. Therefore MPB is very suitable for rapid repairing of concrete structures.
Research on the Swelling Characteristics of Expansive Soil
Authors: Fu Wei , Wu Wan Ping , Wu Sha , He Bin , Ruan Yan Bin
Published: May 2011

Swelling tests of remolded expansive soil with water immersing are carried out by use of the simple consolidometers. The swelling characteristics of the expansive soil under the different initial conditions are studied. The Dose Response model is used to fit the rules of swelling time interval for expansive soil with water immersing. The quantitative relationship among the swelling and initial overburden pressure, initial water content and initial dry density is attained by use of the three dimensional regression analyses. The important index obtained could be provided to the engineering design, construction and stability evaluation of expansive soil slopes.
Effects of Humidity Field on Creep of Reinforced Concrete Beams
Authors: Du Shi Lei , Han Bing , Zhang Zheng
Published: May 2011

Creep, as one of the most important properties of concrete, has important influences on concrete structures. In present domestic researches, studies on humidity diffusion in concrete are relative inadequate; and few models can take comprehensive consideration on humidity factors. According to humidity diffusion theory of concrete, this paper studied the distribution of humidity field within concrete at constant humidity condition by using finite element method. Based on the drying creep of the Model B3, this paper analyzes the effects of humidity field on creep of RC beams.
The Bearing Capacity Analyses of Soil beneath the Blade of Circular Cassion
Authors: Yan Fu You , Guo Yuan Cheng , Liu Shang Qian
Published: May 2011

Based on the assumption of pointed blade of circular cassion, the formulas of the bearing capacity of soil beneath the blade are presented by the slip line method. The values of Nγ are not too sensitive to change for the soil’s internal friction angle, and are significantly greater than those obtained by Terzaghi’s and Berezantsev’s formulas. They decrease with an increase in the value of blade embedment depth and the taper angle.
Experimental Research on Determining the Geotechnical Parameters with CPTU Methods
Authors: An Yan Yong , Wang Bao Tian
Published: May 2011

Cone penetration test is a fast and efficient in-situ test technique. With the development of sensor technology and the use of new probes, such test is employed in more fields and reveals more soil parameters. Based on the advanced CPTU equipment, porewater pressure dissipation processes were measured at different depths, dissipation characteristics of the sandy soil and cohesive soil were analyzed respectively; Then, consolidation and permeability coefficients of the cohesive soil were calculated, the results are close to the laboratory test results. Undrained shear strength of soft clay were determined use theoretical and empirical methods, calculation accuracy of these methods were analyzed and the results show that the total cone tip resistance method is in good consistence with the measured values. CPTU is able to provide plenty of geotechnical parameters; therefore, more experience of regional tests should be drawn so as to produce more economic and technical benefit in the future.
Effect of Naphthalene Based Superplasticizers on Performance of Ultrafine White Cement
Authors: Guo Wei Juan , Du Gao Xiang , Xue Qiang , Liao Jing Hui
Published: May 2011

The compressive strength of ultrafine white cement samples at three ages: 3, 7 and 28 days and micro appearance of hydrates were tested. The influence of the usage of superplasticizers on the compressive strength of ultrafine white cement paste and hydrates were investigated. The results indicated that the 28d compressive strength of ultrafine white cement with 3% naphthalene based superplasticizers added was 92.9 MPa, 22.9% of that of pure ultrafine white cements (75.6 MPa). The addition of superplasticizers was beneficial to the density of white cement paste. A large number of hydrates (AFt, C-H-S, and so on) were generated in the capillary pores, which would improve the structure of capillary pores of hardened cement paste, increase the density and strength.
Fractal Approach on Quantitative Analysis of Micro Pore Structure of Isotropic Consolidated Clay
Authors: Liu Xiao Xuan , Zhang Ji Ru
Published: May 2011

The micro pore structure of isotropic consolidated clay was studied by using a scanning electron microscope (SEM). A digital imaging technique was applied to analyze the evolution of size, number of pores and their distributions in the process of isotropic consolidation according to the SEM images. Based on the fractal concepts of Koch curve and Sierpinski carpet, the Koch fractal dimension Dk and the Sierpinski fractal dimensionDsof soil pores are obtained from the measured data. The variations of bothDkandDsfollowing the change of micro pore parameters and mechanical properties of clay are investigated. The results show that the porosity and pore size decreases as the consolidation pressure increases, and the range of pore size becomes narrower.Dkreflects the degree of irregularity of the pore-solid interface in soil, and the larger theDkthe more irregular the soil pore profile. The distribution of Dkwas found in agreement with a total normal distribution in soil pore. The magnitude ofDsreflects the variation of porosity of clay under isotropic consolidation. Large fractal corresponds to large consolidation pressure and small porosity.Dsdisplays a significant linear regression relationship with porosity, consolidation pressure, consolidation deformation of clay and an exponential growth relationship with permeability coefficient of clay. Both Dk andDsis sensitive to isotropic consolidation of soil and they may be cited as useful indicators for soil consolidation.
Detection of Groundwater Aquifer Using Resistivity Imaging Profiling at Beriah Landfill Site, Perak, Malaysia
Authors: Zawawi Mohd Hafiz , Syafalni  , Abustan Ismail
Published: May 2011

This study explains the use of resistivity imaging profiling. The Resistivity Imaging Profiling (RIP) became the one of some important techniques in order to get more information for finding out some hidden water in geophysical survey and this has been applied in Beriah Landfill Site in task of exploring the location storing underground water. Two dimensional geoelectrical imaging has been applied for this study. The method can be used for map the distribution of resistivity for the subsurface materials layer. The principle goals of this survey are to define the depth of aquifer layers from the subsoil, the water table and the depth of bedrock as well as suitable site for well. The imaging method was used in this study to map the subsurface soil and groundwater in and around the landfill area that includes six resistivity line. Surveys were conducted using SAS4000 resistivity meter and ABEM LUND electrode and the measured resistivity profiles were interpreted with 2-D resistivity inversion programme (RES2DINV) software presented by two dimensions which is axis-x represent as a length on the ground surface while axis-y referred to the depth of the subsurface in meter.
The Calculation of Stress Intensity Factors and the Analysis of Propagation Characteristic of Crack at Hole
Authors: Lu Li Jun , Liu Jian Ping , Li Zhong Mei
Published: May 2011

This paper focusing on the crack at hole of guyed-mast’s ear-plate connecting cables and shaft of guyed-mast, adopting two degree of freedom crack propagation model, track the crack propagation according to the increment of the deepest point and the surface point on the crack front of crack at hole of guyed-mast’s ear-plate. The stress intensity factors of I,II and III type crack with given shape and size have been calculated via finite element method, and a numerical method of calculating stress intensity factors with any shape and size crack has been proposed; furthermore according to modified I, II and III type compound crack propagation velocity formula on the basis of Paris crack propagation velocity formula, we analyzed the changing of crack shape parameter a/c with crack size parameter a/T of crack at hole of ear-plate connecting cable and shaft of guyed-mast by numerical integration method and obtained the propagation characteristic.
Study on Seismic Performance of Raw-Soil Structure in China
Authors: Bu Yong Hong , Wang Yi Hong , Yin Ye
Published: May 2011

First, the features of raw-soil structure in China are introduced briefly from its building materials, its building mode, its structure system and houses damage in the earthquakes. Then its research process and present condition is summarized, and the results of investigation in recent years of raw-soil structure in China are presented. For raw-soil structure in China, the development of experimental study on the seismic performance is expounded from the performance of its materials, the bearing capacity and seismic performance of the bearing wall, its constructional measures, and the whole of the structure, etc. The results of constructing method and related norms written of raw-soil structure are summarized. The problems of the seismic ability of raw-soil structure are pointed out. Finally, the development of raw-soil structure in China is predicted in the future.
Numerical Simulation of Grout Curtain in a DEWPR Tunnel
Authors: Wang Jian Xiu , Feng Bo , Wang Pei , Tang Yi Qun , Yang Ping
Published: May 2011

Grouting is often adopted in a tunnel to resist high external water pressure; the tunnel is defined as External Water Pressure-Resistant Tunnel (EWPR Tunnel). When the grouting reinforcement does not seal the high pressure groundwater completely and the leakage groundwater is drained by drainage system, the tunnel can be called a Drained External Water Pressure -Resistant Tunnel with limited Drainage (DEWPR Tunnel), the grouting reinforcement and waterproof/drainage system of which are great important and should be considered specially. Take the traffic tunnels of Jinping Second Cascade Hydropower Station as an example, a numerical method is adopted to simulate the influence of grouting reinforcement thickness on the distribution of external water pressure. The results indicate that the discharge rate per unit length is 7.82m2/d with single tunnel drainage and 5.28m2/d with double-tunnel drainage, and the external water pressure can be reduced less than 0.6MPa when the thickness of grouting reinforcement is 12m based on the control factor of volume of water discharge.
Dewatering Preloading Test and Ground Subsidence in a Project
Authors: Zhang Yong Mou , Zhao Jian Chang
Published: May 2011

Ground subsidence is one of the main geological hazards in Shanghai. The ground subsidence is caused by pumping groundwater greatly. In the past, studies of ground subsidence in Shanghai were mostly taken for the ground subsidence caused by pumping confined water in Puxi. And ground subsidence caused by pumping phreatic water was rarely studied. Dewatering preloading is a new technology for soft soil treatment. The monitoring of ground water level, ground subsidence, pore water pressure in the process of dewatering preloading test for a soft soil treatment project in Pudong showed that pumping phreatic water can also cause ground subsidence. The ground subsidence caused by pumping phreatic water was analyzed in this paper. The relationship between phreatic water level and ground subsidence was obtained.
The Influence of Corrosion Types on the Deterioration of Shear Strength of Corroded RC Beams
Authors: Lu Zhao Hui , Yu Zhi Wu
Published: May 2011

The paper examines the effect of the corrosion types of reinforcing steel on the deterioration of shear strength of corroded reinforce concrete (RC) beams. Three possible types of corrosion, i.e., uniform (or general), pitting (or localized) and hybrid corrosion, for RC beams exposed to de-icing salts or sea environments are considered. From the investigation of the present paper, it can be concluded that the corrosion types have great effect on the time-dependent shear strength of a corroded RC beam. Generally, the shear strength degraded fastest for hybrid corrosion among the three corrosion types. When the corrosion rate is relative small, the deterioration of the shear strength for the uniform corrosion is greater than that for pitting corrosion. However, when the corrosion rate becomes larger, the deterioration of the shear strength for the pitting corrosion is greater than that for uniform corrosion as corrosion propagates.
Research on Fully-Enclosed Composite Cable Made with CFRP and High-Tensile Steel Wire
Authors: Chen Yun Gang , Guo Zheng Xing , Chang Han
Published: May 2011

In this paper, the proposed idea of producing fully-enclosed composite cable with CFRP coupling of high-tensile steel wires and the forming technology of the fully-enclosed composite cable body were introduced. The coordination mechanism of the fully-enclosed composite cable, the requirement of equal elastic modulus between high strength steel wire bundle and CFRP were investigated theoretically. We have come to the follwing conclusions: (1) Carbon fiber has the same strain with the high-tensile steel wire under the tension of whole anchorage. (2) The distribution of the force of the composite cable is in accordance with the axial stiffness between the carbon fiber with high-tensile steel wire. (3) To achieve a good synergy between the carbon fiber with high-tensile steel wire, similar or equivalent elastic modulus is required. (4) The stress ratio between carbon fiber and high-tensile steel wire in the fully-enclosed composite cable in engineering application should be controlled around 0.5.
Effects of Soil Properties Uncertainty on Reliability Index of Slope
Authors: Han Bo , Liao Hong Jian , Li Hang Zhou , Xiao Zheng Hua
Published: May 2011

A probabilistic analysis procedure and related algorithms were based on the Monte Carlo simulation method that considers the variability of soil properties in this paper. A homogenous slope example provide insight into the effects of uncertainty due to the variability of soil properties on slope stability .Taking soil parameters cohesion c, friction angle, gravity γ as the basic random variables, the reliability index are calculated using Monte Carlo simulation method taking into account the uncertainties of these basic random variables. The calculated results are compared for four recognized methods of slope stability, which are Ordinary method, simplified Bishop method, simplified Janbu method and Morgenstern Price method. And the influence of soil parameters’ probability distribution model (i.e. the normal distribution and the log–normal distribution), variation coefficient, mean value, correlation between parameters on the reliability index of slope is discussed. The study shows that different soil properties have different influence degree on the reliability index with regard to the slope reliability analysis.