bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental Measurement of Volume Changes on Cement Concrete Depending on the Subsoil
Authors: Kropacek M. , Cajka R. 
Published: June 2019

Abstract
The paper describes experimental measurement of volume changes of cement concrete elements depending on the subsoil. Volume changes of cement concrete (including shrinkage and swelling) are theoretically known and at present there are many calculation models to determine the final shrinkage at the time of the design of the concrete or construction. The subsoil beneath the concrete structure has a significant effect on the volume changes of the concrete, and this behaviour must be considered when designing. However, the calculation models do not consider the influence of the subsoil and friction effects. The experiment described in the article includes the behaviour of different concretes on differently defined subsoils. At the defined input conditions, volume changes have been measured over the long term in different climatic conditions. The result of the experiment is the values of volume changes, depending on the concrete-subsoil interaction.
Breaking of Key Layers and Surface Subsidence in the Loess Mountainous Areas
Authors: Lv Ke , Wang Jinan 
Published: June 2019

Abstract
During the process of mining subsidence, the thick loess layer will have certain cohesion, tensile strength and flexural strength. Therefore, the thick loess layer may have a significant impact on the overburden load of the mining area, which further affects the fracture and surface subsidence of the overlying strata on the working surface. The calculation model was constructed based on the mining geological conditions of the loess mountainous area in Jinhe Coal Mine of Gansu Province. The mining surface and process were simulated by FLAC3D, and the load effect of loess layer thickness on its lower strata and its key layers was analyzed. The results show that the surface loess layer is mainly caused by tensile failure, and the other rock layers are mostly shear failure. The key layer has obvious control effect on surface settlement, and its fracture can lead to significant settlement on the surface. Under the condition of thick loess layer, the initial breaking distance of the key layer is larger than that of the critical mining length. The results show that the equivalent load coefficient of the loess layer is obtained and applied to the calculation of the fracture distance, which can obtain more realistic parameters.
Numerical Simulation Parametric Studies on Concrete-Filled Steel Tubular Columns
Authors: Zhao Lidong , Cao Wanlin , Ye Taopin 
Published: June 2019

Abstract
The finite element(FE) software is used to simulate concrete-filled steel tubular(CFST) columns. Based on the existing experimental data, the model is verified. The parameters studied include axial load ratio and shear span ratio, and the difference of seismic performance between circular CFST column and square CFST column under the condition of equal steel ratio is compared. The results show that with the decrease of axial load ratio, the hysteretic curve is plumper and the seismic performance is more stable. With the decrease of shear span ratio, the horizontal bearing capacity of the specimen increased significantly, but the cumulative damage effect was more significant. The simulation results also show that when the steel ratio is identical for circular and square CFST columns, the circular CFST column has superior seismic performance.
Design and Implementation of 3D Urban Underground Pipe Network System
Authors: Pang Liyang , Lan Guiwen , Tao Yanyu 
Published: June 2019

Abstract
For the sophisticated spatial relationships of the urban underground pipeline networks, 3D visualization technology has become widely used for management and maintenance purposes of these types of underground utilities. With the increasing number of pipeline incidents, there is an urgent need for effective solutions for improving the management of urban underground pipe networks. In this paper, through a thorough analysis of the pipeline network management, a 3D urban underground pipe network system (3D UUPNS) was designed and implemented by using SuperMap.Net. The 3D models of the pipeline network and ground buildings are rendered by using SuperMap RealSpace Library, with 3D models of ground buildings being cached into OSGB format. Some analysis functions such as excavation analysis and section analysis, have been developed to support the management and operations of underground pipelines.
Influence of Mineral Admixture in CSA Cement on Chloride Binding Capacity
Authors: Jiang Xuelei , Zhong Zhenhao , Liu Wei 
Published: June 2019

Abstract
Increasing chloride binding capacity of hardened cement paste is an effective method in reducing corrosion risk of reinforcement in concrete structures exposed to marine environment and guarantee its designed service life. Compared with traditional Portland Cement, Calcium Sulfoaluminate Cement (CSA) has been proved for its better chloride binding capacity in practice. However, in order to save cement consumption and reduce environmental pollution, it is important to investigate the influence of mineral admixture on the Cl− binding capacity of CSA cement. Based on this background, authors of this paper studied influence of key parameters within CSA-Cl− mix proportion, i.e. mixtures like Calcium carbonate (C), Slag (S), Fly ash (F) and Metakaolin (M) and use of gypsum and studied its effect on the chloride binding capacity. Meanwhile, the Cl− binding mechanism was also explored by means of XRD and TG. From the results obtained, it can be concluded that the use of gypsum led to an increase in ettringite, which caused a severe drop in chloride binding capacity; the addition of mixtures led to an increase in chloride binding capacity.
Experimental Study on Mechanical Properties and Water Permeability about 107 Glue for Slag Permeable Brick
Authors: Chen Xiaoxia , Fan Qingxian 
Published: June 2019

Abstract
The main materials of the slag permeable brick were blast furnace slag, the waste generated in metallurgical industry, cement, and 107 glue as well, which were used in architecture as main cementitious material. The influence of 107 glue on the mechanical properties and water permeability of slag permeable brick were analyzed, and the formula and technological parameters of permeable brick were optimized by the method of contrast experiment. The permeability coefficient was the best when the compressive strength was satisfied, and the optimal mix ratio was also determined.
On Dynamic Constitutive Model of Granite Under Impact Loading: Effect of Damage on Dynamic Strength
Authors: Liang Shufeng , Ling Tianlong , Liu Dianshu , Li Shenglin 
Published: June 2019

Abstract
Dynamic mechanical properties of granite were tested by a split Hopkinson pressure bar system at constant strain rates. The experimental results show that granite behaves linearly elastic at the initial loading stage, followed by a significant plastic deformation after yielding, and yield strength, ultimate strength and elastic modulus are all rate dependent. On this basis, the simplified Zhu-Wang-Tang (ZWT) constitutive model is applied in this paper, assuming elastic and high frequency viscoelastic elements only. The damage evaluation equation is introduced to the simplified ZWT model to investigate the effect of damage on the dynamic strength of granite due to impact load. Finally, the proposed model is applied to fit the experimental data. It is known that the fitted stress-strain curves at different strain rates are in agreement with the experimental ones. Compared with experimental data, the error of yield stress, peak stress and corresponding strain obtained by fitting method are all not larger than 10%. This demonstrates that the proposed dynamic constitutive model can accurately describe the dynamic mechanical properties of granite under impact loading.
Fine Tailings Heap High Levels of Radiation Seepage Drainage Wells Application
Authors: Zeng Kaihua , Dai Hongtao , Yao Hui 
Published: June 2019

Abstract
Jiangxi Xingan Xinheng mining tailings, the tailings discharge chute fracture accident, backfilling materials caused by leakage. After emergency measures for drainage tunnel mouth sealed, to make the library lost only drainage channels, the backfilling is fine drainage is poor, saturation line rising, pose a safety hazard. In this paper, Xinheng mining tailings as an example, put forward the suitable level of tailings backfilling fine particle size, small permeability coefficient e radiation well engineering measures and construction technology, let the radiation well drainage and horizontal tube drainage measures etc, for drainage effect comparison and analysis, the results show that, using the radiation well drainage measures more outstanding. Short construction time limit for a project, drainage effect is good, can provide the basis for other similar tailings e measures adopted and the reference.
Elastic Modulus Reduction Method Based Ultimate Bearing Capacity Analysis of CFST Truss Arch
Authors: Zheng Jian , Wang Jianjun , Yang Lufeng , Xie Weiwei , Zhao Yufeng 
Published: June 2019

Abstract
In order to evaluate the application of elastic modulus reduction method on the ultimate bearing capacity analysis of CFST truss arch, the elastic modulus reduction method was compared with the test data and the increment nonlinear finite element method. Firstly, the element bearing ratio was defined according to the homogeneous generalized yield function, and the principle of deformation energy conservation was adopted to derive the elastic modulus adjustment strategy, based on which the modulus reduction method was developed for the ultimate bearing capacity analysis of CFST structures. Then, combined with the incorporated strength capacity technique, the section strength was modified to consider the structural constant load effect. Finally, the ultimate bearing capacity of a CFST truss girder and 136m span truss arch was obtained on the basis of the proposed method, and the results were compared with the test data and the incremental nonlinear finite element method. The results show that the elastic modulus reduction method can achieve high calculation accuracy and wide application for the ultimate bearing capacity analysis of CFST truss arch.
Calculation Method of Flexural Capacity of Composite Beam in Negative Moment Area after Corrosion of Interfacial Bolt
Authors: Xu Bo , Zhu Weiqing , Shang Yang 
Published: June 2019

Abstract
In order to quantitatively calculate the stud shear bearing capacity after corrosion, this paper used the stud shear bearing capacity factor after corrosion to represent the stud corrosion degradation effects, and based on the analysis of the reasons for its reduction, the product between stud effective section area after corrosion and stud tensile strength was proposed to calculate the shear capacity coefficient. At the same time, based on the assumption of plasticity theory, the simplified calculation formula of the composite beam flexural capacity under hogging moment was derived by simplifying the sum of the flexural capacity of the steel beam, the longitudinal reinforcement in the concrete plate and the stud. The effect of interface stud corrosion for the flexural bearing capacity of steel-composite composite beam was considered by multiplying the stud Shear capacity coefficient after its corrosion, and the experimental data of 11 beams were combined to verify. The results showed that the calculated results of this method were highly consistent with the experimental results in the literature. The calculated results were on average less than 2% of the experimental results, and the coefficient of variation was only 0.01. The calculated results of the formula were consistent with the results of theoretical analysis in the literature, and the calculation method was simple and convenient. It can be evaluated for the composite beam flexural capacity under hogging moment with corroded shear studs
Contrastive Analysis of Indoor Model Test and Numerical Test on Pull-Out Failure of Fully-Embedded Anti-Slide Pile
Authors: Qiu Peng 
Published: June 2019

Abstract
In this paper, the strain of steel bar, concrete of pile body, displacement of pile top and earth pressure around piles are monitored under pull-out failure mode of fully-embedded anti-slide piles, and the stress mechanism of fully-embedded anti-slide piles is studied by numerical simulation. The results show that when the anchorage depth of anti-slide piles is insufficient, the rigid rotation of piles is dominant, and the strain change of pile body is not obvious. Through the analysis of the working parameters of the anti-slide pile, it is concluded that both sides of the loading point of the anti-slide pile are subjected to an upward pulling force, which makes the anti-slide pile tend to pull out. Through the simulation analysis of the model test, it can be concluded that with the increase of load, the sliding up-welling zone behind the pile tends to expand, and the pile body is subjected to a “pull-out” effect of the surrounding sand.
Study on the Parameters of Roadside Support after the Cantilever Beam of the Basic Roof with Height of Fracture Zone Cut by Deep-Hole Blasting
Authors: Hu Tao , Hou Gongyu , Li Zhuhe , Chen Jianpeng 
Published: June 2019

Abstract
In order to determine the reasonable parameters of roadside support, based on the analysis of the law of surrounding rock activity in gob-side retaining roadway, it is proposed that the relationship between different parameters of roadside support wall and its supporting resistance is calculated and analyzed by using the improved mechanical model after deep-hole blasting roof cutting and improving the external mechanical environment of surrounding rock then. The mechanical equation for calculating the width and strength of supporting wall near roadway is derived. The analytical solution of width and strength value of roadside support under roof cutting condition is obtained, and field application is carried out in 3207 working face of Nanyang Coal Mine. The results show that it is feasible to set the height of the upper-side fissure zone of the goaf beside the roadway as the height of the cutting roof; it is reasonable to calculate the height of the cut roof as the height of the static block; the formula of the width with a certain strength of the roadway support wall obtained in this paper and the redundant safety factor of the parameters of the roadway support wall tried to be adopted are effective. Finally, after improving the external mechanical environment of retained roadway surrounding rock, reasonable parameters of roadside support are the guarantee to ensure the stability and integrity of retained roadway structure along goaf.
An Improved Seismic Damage Assessment Model for Buildings Based on Parallel Algorithms
Authors: Feng Biao , Lan Riqing , Yu Shizhuo 
Published: June 2019

Abstract
The efficiency of post-quake emergency management depends heavily on the speed of seismic damage assessment software, which depends on the evaluation algorithm essentially. Traditional seismic damage assessment models based on sequence algorithms usually need tens of minutes to get visualized results. More efficient computing models for seismic damage assessment are demanded urgently. General parallel evaluation algorithm based on GPU computing framework was investigated by the authors, and an improved seismic damage assessment model for buildings was proposed in this paper. We designed a three-level parallel scheme to accelerate the computing and visualization. At the top level, the earthquake area is divided into smaller regions, such as cities or counties. At the middle level, fundamental geographic data for each region is split into layers by features. At the bottom level, buildings are grouped into several types, which can be processed by GPU cores simultaneously. The developed model can estimate and analyze the seismic damage of buildings and the spatial distribution of victims in earthquake region more rapidly than traditional models.
The Analysis of Interface Normal Stress of Short Column of Square Concrete-Filled Steel Tube with Axial Compression
Authors: Zhang Zhengqi , Liu Yongjian , Zhang Zhiheng , Cheng Gao 
Published: June 2019

Abstract
The interface normal stress reflects the interaction between the steel tube and the concrete in the tube, which is helpful to distinguish the time and size that begin to appear confinement effect of the concrete filled steel tube. The typical CFST members in engineering applications may be loaded such as loading through the whole cross section, loading through steel alone and loading through concrete alone, etc. Establishing nonlinear finite element model to analyse the interface normal stress between steel and concrete along the section width, short column height and with the change of axial compressive load, the results show that the different loading mode of CFST column interface normal stress along the width of the cross section showed a “trough” distribution, but the value is different, sorted by size in descending order is loading through concrete alone, loading through the whole cross section, loading through concrete alone. When steel tube and concrete are subjected to loads, the effective length of steel tube confined concrete is about 0.55 times the width of the section, and the normal stress of the interface is almost 0 in the unconstrained area after 0.5 times of the ultimate load.
Construction Monitoring and Numerical Simulation Analysis of the Yangwujian Soft Rock Tunnel
Authors: Zeng Kaihua , Yu Jia , Li Xuejun 
Published: June 2019

Abstract
Tunnel construction monitoring plays a key role in excavation construction of soft surrounding rock tunnel, it can be accurately judged stability of surrounding rock, its provide more priority information to design and construction. This paper adopts to construction of New Austrian Tunnel-ling Method (NATM), by strengthening the supporting and actual measurement on the spot, obtained displacement curve above vault settlement and clearance convergence. Selection parameter of supporting structure property by using Midas-GTS finite element analysis software, as well it has obtained both upper guide and down guide clearance convergence displacement-excavation step curve and valut settlement-excavation step curve. It’s found that: the faster stage of changing velocity is the first 10 days; the optimal execution time of the secondary lining is that the tunnel was excavated 30 days. It’s almost anastomosis both numerical simulation analysis and actual monitoring, it is better confirmed correctnass to establish the tunnel model, which provide reference for design and construction.
Numerical Calculation of Instability of Tunnel Surrounding Rock Based on Elastic Hole Theory
Authors: Yang Haobo 
Published: June 2019

Abstract
The instability and unloading of surrounding rock structure in tunnel under TBM construction condition can easily induce large-scale rock caving in heading face, which seriously restricts safe and efficient tunneling. Aiming at the instability problem of surrounding rock structure of tunnel constructed by TBM, four types of slope induced by excavation disturbance are summarized systematically based on elastic hole theory, and the instability mechanism of roof structure and surrounding rock of tunnel is analyzed; the instability mechanism and catastrophic characteristics of surrounding rock structure of tunnel are analyzed by FLAC3D finite element numerical calculation software, and the roof transportation of tunnel after supporting is carried out. The amount of movement is greatly reduced and the overall failure degree of overlying strata is slowed down. The results show that the roof is prone to structural instability under the influence of tunneling disturbance. Tunnel support can effectively hinder the movement of overlying rock roof and floor, alleviate the probability of rock mass catastrophe, effectively control the dynamic disasters, and achieve safe tunneling.
Simulation Analysis of Frame Structure Acceleration Response in Subway Buried Blasting
Authors: Guo Weina , Bi Weiguo , Ren Sijian 
Published: June 2019

Abstract
In order to analyze the response of the acceleration peak in different directions of frame structure to the variation of blasting distance and layer height in the shallow blasting. Based on the shallow blasting of subway, this paper uses ANSYS/LS-DYNA finite element analysis software to construct the framework structure calculation model and simulate the acceleration peak. The results show that the acceleration peak of the frame structure appears between the vertical three-layer and four-floor, and the longitudinal acceleration peak is one order of magnitude larger than the lateral direction. The acceleration peak and the blasting distance are negatively correlated, which is positively correlated with the layer height. Therefore, before the blasting construction, the seismic strengthening of the thin layer of the intermediate layer of the multi-layer frame which is close to the source of the explosion must be carried out.
Comparative Analysis of Performance of Porous Asphalt Pavement and SMA Pavement Based on Deck Pavement Structure
Authors: Yang Zhihao , Xu Bin , Cao Dongwei 
Published: June 2019

Abstract
Viaducts are more and more widely used in China. How to ensure the safety of the bridge deck has become a hot issue of concern? Based on the above problems, the application of porous asphalt pavement in bridge deck pavement is also increasing. Based on the porous asphalt pavement project of Shijiazhuang City Ring Road (West Second Ring of Heping West Road), the performance differences between porous asphalt pavement and stone matrix asphalt pavement were studied. By comparing the gradation characteristics and performance of porous asphalt mixture and stone matrix asphalt mixture, the advantages and disadvantages of the two mixtures in road performance were analyzed. At the same time, we carried out on-site braking test, noise test and long-term temperature monitoring on two types of pavement. By comparing the test results, we thought that porous asphalt pavement could reduce the braking distance by up to 7 m in mid-to heavy rain weather, and porous asphalt pavement could reduce 2-6 dB noise, Porous asphalt pavement has better cooling effect than stone matrix asphalt pavement, and the higher the external temperature was, the better the cooling effect of porous asphalt pavement was, and it could reduce 6-8°C in summer. Through the test comparison, we draw the conclusion that the pavement performance of porous asphalt pavement is better than that of stone asphalt pavement.
Research on the Quality Control Technology of Dam Shoulder Groove Project of Wudongde Hydropower Station
Authors: Ming Ming , Liu Yang 
Published: June 2019

Abstract
The shoulder groove project of Wudongde dam is a key program of the entire Wudongde Hydropower Project. The slope of the dam project is centered on the dam shoulder groove, where the upstream is the upstream shoulder and the power station intake, and the downstream is the downstream shoulder, plunge pool, second dam and downstream revetment. Therein, the excavation quality of the dam shoulder groove directly affects the long-term safety of the dam operation. The dam shoulder groove excavation elevation is 988m-718m, with the excavation height of about 270m, the excavation width of 18.32-51.42m, and excavation slope ratio of 1:0.21-1:9.2. The slope changes from steepness to slow, and there is no horse track set in the middle. Since the excavation quality directly affects the long-term safety of the dam operation, this paper deeply analyzes the influence factors of the relevant quality control requirements such as over-under-excavation, flatness, half-hole rate and blasting depth of the dam shoulder groove project of Wudongde Hydropower Station through integration and modularization of its key processes. This paper has a certain practical significance for the formation of the theoretical system and practical foundation of quality control technology for abutment trough of high slope dam of large hydropower station.