bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Anti-Mud Agent on the Performance of Gangue Backfilling Paste
Authors: Zhou Wei , Guo Zhaoyang , Wang Kangkang , Zhang Haibo , Guan Xuemao 
Published: June 2023

AbstractAnti-mud agents could improve the efficiency of the action of water reducers in concrete by preferentially. The anti-mud agent was preferentially adsorbed on the clay surface, which reduces the ineffective adsorption of the water reducing agent to the paste, thereby improving the water reduction efficiency. However, its application in high-sediment content coal gangue gypsum backfill materials had not been reported. In this paper, The competitive adsorption mechanism echanism of anti-mud agent was first described. Tested its competitive adsorption with water reducer molecules on the surface of gangue powder. The influences of anti-mud agent on the slump, coagulation time and compressive strength of the paste at different ages were studied. The results showed that: as the dosage of anti-mud agent increased, the amount of desorption of the water reducer from the surface of gangue powder increased. When adding the same extra amount of water reducer, the slump of the backfill paste material increased with prolonged the coagulation time. The strength of the paste decreased at 3 d, and the strengths of 7 d and 28 d were not significantly deteriorated. A small amount of anti-mud agent could greatly improve the fluidity of the paste. This study provides a scientific basis for the pumping of pure solid waste paste.
Research and Application of Anchorage Vertical Loading System in Building Reinforcement and Rectification
Authors: Li Zhao , Sun Xunhai , Jia Ning , Zhou Shengbin , Yang Xinhui , Tong Jianxing , Yang Haitao 
Published: June 2023

AbstractIn this paper, the settlement and tilt of a building in north China are taken as an example. The differential settlement of the building is not stable, and the tilt continues to increase. After the rectification measures of forced landing by digging out the soil were taken, the expected effect was not achieved. Then the auxiliary rectification was carried out by means of centralized and cyclic loading through the anchorage vertical loading system, and the automatic dipmeter and manual monitoring are adopted in the process of deviation rectification to achieve information construction. At present, the construction of this project has been completed and the effect of reinforcement and rectification is good, which can provide reference for similar projects and has certain promotion and guidance significance.
Stability Analysis of Earth and Rock Dams During the Construction Period of Soft Foundation Reinforcement
Authors: Li Jiahao , Xu Jingnan , Zhao Shiwen , Wu Junhua 
Published: June 2023

AbstractThe consolidation of earth and rock dam foundations and its effect on stability is a key concern in water conservancy and water transportation projects. It is common to use the vacuum combined pre-pressure method to deal with soft ground foundation, where the reasonable selection of soil consolidation coefficient is one of the important factors to determine the success of the project. In this paper, numerical simulation is used to study the strength law of soil and rock dam foundation under different consolidation coefficients of soft ground, and the corresponding stability coefficients of soil and rock dam are obtained. On this basis, the reinforcement effect of an additional counter pressure platform is proposed and analyzed. The results show that the larger the consolidation coefficient of soft ground is, the more it is conducive to the growth of the strength of the soft soil layer and can effectively improve the stability coefficient of the earth and rock dam. At the same time, the additional counter-pressure platform has a certain effect on the overall stability enhancement of the earth and rock dam. The research results can provide a reference for the application of vacuum combined pre-pressure method to earth and rock dam projects.
Seepage Analysis of Drainage Decompression in Sloping Basement
Authors: Li Shuijiang , Wan Quanbin , Yan Haorong , Pan Hong 
Published: June 2023

AbstractThe accidents of bottom floor cracking occur on underground structure due to uplift pressure. Especially in the southern rainy area, super large buildings on slope with high underground water level are in a complex seepage field and it is hard to deal with. In order to solve this problem, a residential district in Guangzhou as an example is analyzed through multiple stratigraphic level of 2D finite element method to the most dangerous conditions of the seepage field. The more reasonable and economic drainage decompression measures, " relief well + sand cushion", are put forward, which can meet the requirement of decompression. Finally, the monitoring data further validate the rationality of the method.
Effect of Autoclaved Aerated Concrete on Dynamic Response of Concrete Gravity Dam Under Earthquakes
Authors: Zhao Fei , Zhao Shaoyu , Fan Shuli 
Published: June 2023

AbstractAutoclaved Aerated Concrete (AAC) is commonly used in lower floors buildings in low seismicity areas due to its lightweight property and high energy absorption capacity. This paper proposes a novel application of AAC as an effective seismic countermeasure in the reduction of vibrational energy for concrete gravity dam. According the vibrating characteristics and failure modes of gravity dam under earthquake excitation, AAC was placed in the upper zone of a gravity dam to reduce the seismic inertia force and consequently to increase the seismic safety of the dam. Dynamic responses of two non-overflow sections of a gravity dam were analyzed through finite element analysis utilizing a damaged plasticity constitutive model. The anti-seismic effect of using AAC in gravity dams is researched by inputting different kind of ground motion records. The comparison of the natural vibration characteristics, dam crest displacement, and dynamic damage of the dam were investigated. The results show that, AAC effectively improves seismic resistance of concrete gravity dams, particularly eliminating cracks in the concrete along reduced damage zones, through inertial force reduction and energy dissipation. The results warrant further considerations for applying AAC to gravity dams.
Application and Numerical Simulation of Key Technologies for Deep Foundation Pit Support
Authors: Tong Jingsheng , Zhang Hongmei , Zhang Weiqiang 
Published: June 2023

AbstractThis paper adopts the key technology “tunnel and underground space support components”, assembles it into a “honeycomb” structure type, and expands its application to deep foundation pit support engineering, which fully reflects the combination of “industry-university-research” theoretical research and engineering practical application. This key technology of support can optimize the setting of lateral support components in the deep foundation pit support process, optimize and improve the current conventional deep foundation pit support construction technology, and has good research and industrialization promotion and application value. In this paper, the deformation and stress–strain analysis of each working condition of excavation of the foundation pit are also carried out through numerical simulation, and the uplift displacement and stress change of the foundation pit bottom are within the safety range of stress control, and the supporting stress is far lower than the bearing capacity of the prefabricated components, which further verifies the practicability and reliability of the key innovative technology.
The Effect of Replacing Natural Aggregate with Geopolymer Artificial Aggregates on Air Voids of Hot Mix Asphalt
Authors: Karyawan I Dewa Made Alit , Ekaputri Januarti Jaya , Widyatmoko Iswandaru , Ahyudanari Ervina 
Published: June 2023

AbstractHigh voids in hot mix asphalt (HMA) can increase sensitivity to moisture, resulting in premature failure of asphalt pavements. The use of artificial aggregates as a substitute for natural aggregates has been considered in this paper to optimize air voids that meet the requirements. The reason is that natural aggregates are non-renewable raw materials and their availability continues to decrease. This study aims to determine the effect of replacing some natural aggregates with artificial aggregates on air voids. This experiment assessed 2 sets of HMA standard gradations, namely the Bina Marga standard (Indonesian standard) and the Federal Aviation Administration (FAA) standard. For each set, 2 different raw materials are used, namely: 1) asphalt mixture using 100% natural aggregate and 2) asphalt mixture using a combination of 25% artificial aggregate and 75% natural aggregate. The analysis includes volumetric mixes, such as VIM (voids in mix), VMA (voids in mineral aggregates), and VFA (bitumen filled voids). The results of the analysis found that the replacement of natural aggregates with artificial aggregates affected the cavities formed in the asphalt mixture. HMA that uses natural aggregates, shows VMA, VFA and VIM that meet the requirements for pavement surface materials.
Finite Element Analysis of Reinforced Hollow High-Strength Concrete Filled Square Steel Tubular Middle-long Column under Eccentric Load
Authors: Yang Zhijian , Li Jixing , Li Guochang , Cui Weizhe 
Published: June 2023

AbstractTraditional hollow concrete filled steel tube components are mainly used in the transformer power structure. In order to improve the mechanical properties and application scope of hollow concrete filled steel tube components, a new type of reinforcement hollow steel tube high-strength concrete combination structure is proposed. Given that the components in the construction system are frequently in an eccentric stress condition throughout the structural system, the finite element analysis program ABAQUS produces 20 eccentric compression middle-long column models. The overall force process of the composite members is investigated, and parametric analysis is done on the yield strength, eccentricity, steel content, and various lengths to slenderness ratios of the various steel components. According to the results of finite element analysis, the stress process of reinforced hollow high strength concrete filled square
steel tube components is mainly divided into four stages: elastic section, elastic–plastic section, plastic strengthening section and descending stage. The configuration of steel bars in the composite components can significantly improve the ductility of the composite components. This new combination structure can be used as a wind-resistant column in industrial plants in the future, which has certain application prospects and economic benefits.
Effect of Cross-Section Shape on RC Specimen’s Behavior Under Asymmetrical Impact Loading
Authors: Al-Bukhaiti Khalil , Yanhui Liu , Shichun Zhao , Daguang Han , Abas Hussein 
Published: June 2023

AbstractBy applying asymmetrical lateral impact forces on RC specimens, the specimens’ cross-sectional shape is analyzed. The effectiveness of the RC specimens’ resistance to impact was examined using a drop hammer. Performing research on the factors that led to the failure of various RC specimen shapes and the dynamic responses they exhibited. In the experiment, eight circular and square specimens were used. Includes the method of failure, the impact force, and the deflection time history. The findings point to shear fractures between the point of impact and the adjacent support. The right side of the impact point has suffered significant damage, and the shear tests on all specimens failed. The peak impact force that square specimens can bear may be greater than circular ones. Protecting the concrete core and reducing maximum deflection are benefits of using a square specimen. When the ratio of stirrups is raised, there is only a little variation in the square specimen’s damage range. This may cause a slight reduction in damage, but it is not significant. The plateau force of a circular specimen can be increased, but only a little. An increase in the stirrup ratio may increase energy use.
Energy Spatial Distribution of Structure Noise Radiated from U-beam Slabs
Authors: Zhou Li , Zhang Tianqi , Luo Yanyun 
Published: June 2023

AbstractAt present, the application of U-beams in urban rail transit is gradually increasing, but researches about the bridge structural noise are still insufficient. This article took U-type girder as the research object and studied the structural noise distribution on the basis of energies in different frequency band. Firstly, the dynamic response of the bridge under vehicle load was acquired with the combination of finite element simulation method and field test. Secondly, the structure-acoustic coupling finite element-infinite element model of the U-beam was established, and noise fields of the whole U-beam, the floor and the wing slabs were calculated respectively. By calculating the energies contribution of the sound field point in different frequency bands, the spatial distribution of the radiation noise of the floor and the wing slab in the above frequency bands were obtained. The results show that in the frequency range of 20–200 Hz and the main frequency band (40– 63 Hz), the floor plays a major role in most areas of the whole noise field, and the main influence domain of wing slabs is located in the sector area around wing slabs. In the frequency range of 100–160 Hz, the floor mainly contributes to the acoustic energy of the sector region above and below the U-beam.
Cases Study on Foundation Pit Design in Complex Environment of Urban Core Area
Authors: Ma Lili , Chen Yun , Zhang Liang , Zhao Gaigai , Xia Fei , Yang Qinfeng , Zhao Zhiyuan 
Published: June 2023

AbstractWith the degree of urban underground space developing in China, the scale and excavation depth of foundation pit is much larger, and the surrounding environment is also more and more complex. Therefore, five cases of foundation pit design in complex environment have been studied in this paper. Then combined with local engineering experience, a design scheme of foundation pit adjacent to important facilities which is suitable for Qianjiang New Town has been summarized. Finally, based on the five cases, a simple model to assessment the complexity of the surrounding environment is proposed.
Use of Electrical Resistivity Tomography (ERT) for Detecting Underground Voids on Electrical Pylon Installation Sites: Case Studies from Labé Prefecture, Republic of Guinea
Authors: Konaté Ahmed Amara , Kaba Oumar Barou , Conté Mohamed Samuel Moriah , Zaheer Muhammad , Thiam Baye Mbaye , Oularé Fassidy , Diallo Moussa 
Published: June 2023

AbstractThis study was carried out within the framework of the Gambia River Basin Development Organization Energy Project (OMVG), which brings together Gambia, Guinea, Guinea-Bissau and Senegal. The construction of a high voltage interconnection network fed by a hydro-electricity power station to supply power to OMVG member states must be done on stable ground. During the construction of the installation pits for the pylons in Labé Prefecture, cavities in the geological formations were discovered on the initial planned route. Regarding to geotechnical context of subsurface cavities risk it is mandatory to know their exact location in study areas to reduce the potential degree of risk. A field study was conducted to investigate the lithology, as well as in detecting the presence of apparent faults. Geophysical data was collected using Two Dimensional ERT with different electrode spacing to delineate associated subsurface cavities on each site and each cavity respectively. The target depth was 20 m. The result shows that the observed cavities were because of the dissolution of certain minerals constituting the weathering crust due to the infiltration and the seasonal variation in the level of the watercourses. The cavities were almost entirely empty such as in the cases of pylons 213 and 210 indicated that the weathering crust is due to the groundwater infiltration and the seasonal variations in the river flow level. The finding of this study showed that the ERT method have a good applicability in the detection of underground cavities in the study area.
Detailed Analysis of Shrinkage and Creep Effect of Concrete in Prestressed Box Girder Bridge
Authors: Tan Donglian , Ding Wenyuan , Zhao Yue , Yan Chuqin 
Published: June 2023

AbstractFor a 60 m prestressed concrete box girder bridge using structural analysis software as ANSYS and MIDAS/civil, combined with several creep prediction models, a reasonable creep prediction model has been obtained. Considering the influence of prestressed tendon relaxation on the shrinkage and creep of concrete, a refined finite element model is established for numerical analysis and compared with the experimental data. The comparison results show that the calculated value of the refined finite element model with reasonable prediction models and considering the effect of prestress relaxation is closer to the measured value. Finally, the finite element model of solid elements considering the effect of prestress relaxation with the GL2000 creep prediction model is used to analyze the shrinkage and creep effect of a prestressed concrete continuous rigid frame bridge.
On the decoherence of primordial gravitons
Authors: Ning Sirui , Sou Chon Man , Wang Yi 
Published: June 2023

Abstract
It is well-known that the primordial scalar curvature and tensor perturbations, ζ and γij, are conserved on super-horizon scales in minimal inflation models. However, their wave functional has a rapidly oscillating phase which is slow-roll unsuppressed, as can be seen either from boundary (total-derivative) terms of cosmological perturbations, or the WKB approximation of the Wheeler-DeWitt equation. Such an oscillatory phase involves gravitational non-linearity between scalar and tensor perturbations. By tracing out unobserved modes, the oscillatory phase causes faster decoherence of primordial gravitons compared to those by bulk interactions. Our results put a stronger lower bound of decoherence effect to the recent proposals probing squeezed primordial gravitons.
Technology‐assisted anterior cruciate ligament reconstruction improves tunnel placement but leads to no change in clinical outcomes: a systematic review and meta‐analysis
Authors: Yavari Ehsan , Moosa Sabreena , Cohen Dan , Cantu‐Morales David , Nagai Kanto , Hoshino Yuichi , de SA Darren 
Published: June 2023

AbstractPurposeTo investigate the effect of technology‐assisted Anterior Cruciate Ligament Reconstruction (ACLR) on post‐operative clinical outcomes and tunnel placement compared to conventional arthroscopic ACLR.MethodsCENTRAL, MEDLINE, and Embase were searched from January 2000 to November 17, 2022. Articles were included if there was intraoperative use of computer‐assisted navigation, robotics, diagnostic imaging, computer simulations, or 3D printing (3DP). Two reviewers searched, screened, and evaluated the included studies for data quality. Data were abstracted using descriptive statistics and pooled using relative risk ratios (RR) or mean differences (MD), both with 95% confidence intervals (CI), where appropriate.ResultsEleven studies were included with total 775 patients and majority male participants (70.7%). Ages ranged from 14 to 54 years (391 patients) and follow‐up ranged from 12 to 60 months (775 patients). Subjective International Knee Documentation Committee (IKDC) scores increased in the technology‐assisted surgery group (473 patients; P = 0.02; MD 1.97, 95% CI 0.27 to 3.66). There was no difference in objective IKDC scores (447 patients; RR 1.02, 95% CI 0.98 to 1.06), Lysholm scores (199 patients; MD 1.14, 95% CI − 1.03 to 3.30) or negative pivot‐shift tests (278 patients; RR 1.07, 95% CI 0.97 to 1.18) between the two groups. When using technology‐assisted surgery, 6 (351 patients) of 8 (451 patients) studies reported more accurate femoral tunnel placement and 6 (321 patients) of 10 (561 patients) studies reported more accurate tibial tunnel placement in at least one measure. One study (209 patients) demonstrated a significant increase in cost associated with use of computer‐assisted navigation (mean 1158€) versus conventional surgery (mean 704€). Of the two studies using 3DP templates, production costs ranging from $10 to $42 USD were cited. There was no difference in adverse events between the two groups.ConclusionClinical outcomes do not differ between technology‐assisted surgery and conventional surgery. Computer‐assisted navigation is more expensive and time consuming while 3DP is inexpensive and does not lead to greater operating times. ACLR tunnels can be more accurately located in radiologically ideal places by using technology, but anatomic placement is still undetermined because of variability and inaccuracy of the evaluation systems utilized.Level of evidenceLevel III.
Language proficiency of migrants: the relation with job satisfaction and skill matching
Authors: Bloemen Hans G. 
Published: June 2023

AbstractWe empirically analyse the relation between language proficiency and job level of migrants in the Netherlands. A lack of language skills may induce the migrant to work in jobs of a lower level leading to lower job satisfaction. We analyse information about job satisfaction, the fit between the migrant’s education and skill level and the job, and professional level. Men with a higher proficiency level are more satisfied with their type of work and are employed at a higher professional level. For women, no impact of language proficiency can be found.
Does classification of green aid flows matter for environmental quality?
Authors: Apergis Nicholas , Pinar Mehmet , Unlu Emre 
Published: June 2023

AbstractClimate change imposes an existential threat on the globe and has already had sizeable economic costs to countries. Environmental aid flows aim to alleviate the rising concerns of climate change in the developing world. Even though the existing literature has examined the effectiveness of green aid flows for reducing carbon dioxide emissions in the recipient countries, no existing study has examined the effectiveness of different classifications of green aid. Examining the green aid flows to 97 developing countries between 2002 and 2018, we find that all types of green aid significantly reduce carbon dioxide emissions; however, the aid flows targeting the environmental objectives are more effective in reducing carbon dioxide emissions compared to the aid flows that do not target environmental objectives or are not screened. The findings highlight that more aid should be screened and targeted for environmental objectives to increase the effectiveness of green aid flows in developing countries.
Hopf Bifurcations of Moore-Greitzer PDE Model with Additive Noise
Authors: Meng Yiming , Namachchivaya N. Sri , Perkowski Nicolas 
Published: June 2023

AbstractThe Moore-Greitzer partial differential equation (PDE) is a commonly used mathematical model for capturing flow and pressure changes in axial-flow jet engine compressors. Determined by compressor geometry, the deterministic model is characterized by three types of Hopf bifurcations as the throttle coefficient decreases, namely surge (mean flow oscillations), stall (inlet flow disturbances) or a combination of both. Instabilities place fundamental limits on jet-engine operating range and thus limit the design space. In contrast to the deterministic PDEs, the Hopf bifurcation in stochastic PDEs is not well understood. The goal of this particular work is to rigorously develop low-dimensional approximations using a multiscale analysis approach near the deterministic stall bifurcation points in the presence of additive noise acting on the fast modes. We also show that the reduced-dimensional approximations (SDEs) contain multiplicative noise. Instability margins in the presence of uncertainties can be thus approximated, which will eventually lead to lighter and more efficient jet engine design.