Based on the fictitious soil pile model, the effect of sediment on the vertical dynamic impedance of rock-socketed pile with large diameter was theoretically studied by means of Laplace transform technique and impedan...Based on the fictitious soil pile model, the effect of sediment on the vertical dynamic impedance of rock-socketed pile with large diameter was theoretically studied by means of Laplace transform technique and impedance function transfer method. Firstly, the sediment under rock-socketed pile was assumed to be fictitious soil pile with the same sectional area. The Rayleigh-Love rode model was used to simulate the rock-socketed pile and the fictitious soil pile with the consideration of the lateral inertial effect of large-diameter pile. The layered surrounding soils and bedrock were modeled by the plane strain model. Then, by virtue of the initial conditions and boundary conditions of the soil pile system, the analytical solution of the vertical dynamic impedance at the head of rock-socketed pile was derived for the arbitrary excitation acting on the pile head. Lastly, based on the presented analytical solution, the effect of sediment properties, bedrock property and lateral inertial effect on the vertical dynamic impedance at rock-socketed pile head were investigated in detail. It is shown that the sediment properties have significant effect on the vertical dynamic impedance at the rock-socketed pile head. The ability of soil-pile system to resist dynamic vertical deformation is weakened with the increase of sediment thickness, but amplified with the increase of shear wave velocity of sediment. The ability of soil pile system to resist dynamic vertical deformation is amplified with the bedrock property improving, but the ability of soil-pile system to resist vertical vibration is weakened with the improvement of bedrock property.展开更多
AIM:To determine whether the levator palpebrae superioris(LPS)/superior rectus(SR)muscle complex,can influence the position of the upper lid and fornix in acquired anophthalmic sockets.METHODS:This comparative non-ran...AIM:To determine whether the levator palpebrae superioris(LPS)/superior rectus(SR)muscle complex,can influence the position of the upper lid and fornix in acquired anophthalmic sockets.METHODS:This comparative non-randomized and non-interventional study included retrospective data of 21 patients with unilateral acquired anophthalmic sockets repaired with spheric implants.High-resolution computed tomography(CT)measurements of the LPM/SR muscle complex and clinical topographic position of the upper lid,superior and inferior fornix depth in primary gaze position were evaluated.Demographic data were presented as frequency and percentage proportions and quantitative variables comparing the socket measurements with the normal contralateral orbit was statistically analyzed using non-parametric tests considering P<0.05.RESULTS:The anophthalmic orbits had a significantly shorter LPS length(P=0.01)and significantly thicker SR(P=0.02)than the normal orbit.Lagophthalmos was present in anophthalmic sockets but not in normal orbits(P=0.002),while levator function was normal in both(P>0.05,all comparisons).The superior fornix depth was similar in the anophthalmic socket and the contralateral normal orbit(P=0.192)as well the inferior fornix depth(P=0.351).CONCLUSION:Acquired anophthalmic sockets repaired with spheric implants have shorter LPS,thicker SR,and more lagophthalmos than normal orbits.The relationship of the LPS and SR with other orbital structures,associated with passive or active forces acting in the final position of the lids and external ocular prosthesis should be further investigated.展开更多
Piles socketed in soft rock were traditionally regarded as end bearing piles, and the loads transferred from superstructure were assumed in design to be shouldered totally by the piles. This paper was designated to ...Piles socketed in soft rock were traditionally regarded as end bearing piles, and the loads transferred from superstructure were assumed in design to be shouldered totally by the piles. This paper was designated to deal with the interaction between the piles socketed in weak rock and surrounding soil through field measurement. The pile head reaction and ground pressure under piled raft foundation were monitored, respectively. The analysis of the data measured in situ shows the characteristics of the pile embedded in weak rock are similar to that of friction pile to some extent. The rock socketed pile, together with the surrounding soil, shoulders the weight of the superstructure. It is suggested that soil bearing should be considered in designing the soft rock socketed piles, which can make the design more economical.展开更多
A new comprehensive set of data(n = 178) is compiled by adding a data set(n = 72) collected by Arioglu et al.(2007) to the data set(n = 106) presented in Rezazadeh and Eslami(2017). Then, the compiled data s...A new comprehensive set of data(n = 178) is compiled by adding a data set(n = 72) collected by Arioglu et al.(2007) to the data set(n = 106) presented in Rezazadeh and Eslami(2017). Then, the compiled data set is evaluated regardless of the variation in lithology/strength. The proposed empirical equation in this study comprises a wider range of uniaxial compressive strength(UCS)(0.15 MPa 〈 σ_(rc) 〈156 MPa) and various rock types. Rock mass cuttability index(RMCI) is correlated with shaft resistance(r_s) to predict the shaft resistance of rock-socketed piles. The prediction capacity of the RMCI versus r_s equation is also found to be in a fair good agreement with the presented data in Rezazadeh and Eslami(2017). Since the RMCI is a promising parameter in the prediction of shaft resistance, the researchers in the rock-socketed pile design area should consider this parameter in the further investigations.展开更多
Semi-deep foundations socketed in rocks are considered to be a viable option for the foundations in the presence of heavy load imposed by high-rise structures, due to the low settlement and high bearing capacity. In t...Semi-deep foundations socketed in rocks are considered to be a viable option for the foundations in the presence of heavy load imposed by high-rise structures, due to the low settlement and high bearing capacity. In the optimum design of semi-deep foundations, prediction of the shaft bearing capacity, rs, of foundations socketed in rocks is thus critically important. In this study, the unconfined compressive strength(UCS), qu, has been applied in order to investigate the shaft bearing capacity. For this, a database of 106 full-scale load tests is compiled with UCS values of surrounding rocks, in which 34 tests with rock quality designation(RQD), and 5 tests with rock mass rating(RMR). The bearing rocks for semi-deep foundations include limestone, mudstone, siltstone, shale, granite, tuff, granodiorite, claystone, sandstone, phyllite, schist, and greywacke. Using the database, the applicability and accuracy of the existing empirical methods are evaluated and new relations are derived between the shaft bearing capacity and UCS based on the types of rocks. Moreover, a general equation in case of unknown rock types is proposed and it is verified by another set of data. Since rock-socketed shafts are supported by rock mass(not intact rock), a reduction factor for the compressive strength is suggested and verified in which the effect of discontinuities is considered using the modified UCS, qu(modified), based upon RMR and RQD in order to take into account the effect of the rock mass properties.展开更多
Fractures to the orbital walls and floor must be appropriately managed to avoid severe conditions.This results in particularly challenging anatomical reconstructions.The main issues are the implant’s proper shaping,p...Fractures to the orbital walls and floor must be appropriately managed to avoid severe conditions.This results in particularly challenging anatomical reconstructions.The main issues are the implant’s proper shaping,placement,and orientation onto the eye socket.A new,customized implant-shaping mould has already been developed to shape patient-specific implants.However,it still does not address the implant positioning in the fractured orbital cavity.展开更多
Introduction: Leukocyte and platelet-rich fibrin (L-PRF) is an emerging material in dentistry, however, there are controversies surrounding its effectiveness. Despite the amount of literature available, debates regard...Introduction: Leukocyte and platelet-rich fibrin (L-PRF) is an emerging material in dentistry, however, there are controversies surrounding its effectiveness. Despite the amount of literature available, debates regarding its effect continue. This review aims to summarize and clarify the data surrounding the use of L-PRF in promoting the healing of extraction sockets, which may offer a better outcome for future treatments. Purpose: The purpose of this review is to evaluate the current literature on the use of L-PRF in promoting the healing of extraction sockets, and to provide a comprehensive overview of the available evidence. Methods: A comprehensive computer-based search of databases such as PubMed, Medline, and Cochrane Library was conducted. Results: The results of this review suggest that L-PRF has shown promise in promoting early healing of extraction sockets, but the evidence for its effectiveness over a longer period is limited. Conclusion: Although L-PRF has shown promising results in the early healing periods, its effectiveness over a longer healing period cannot be confirmed based on the available data. More clinical trials with standardized protocols and consistent measurement methods are needed to establish the role of L-PRF in enhancing the healing of extraction sockets.展开更多
为明确并提升承插式拼装桥墩抵抗压弯扭等复合荷载的能力,提出了一种结合灌浆套筒和承插口组合连接的新型承插装配式墩,通过复合荷载作用下的拟静力试验对比了现浇(reinforced concrete,RC)、灌浆套筒(grouting and sleeve,GS)、承插口(...为明确并提升承插式拼装桥墩抵抗压弯扭等复合荷载的能力,提出了一种结合灌浆套筒和承插口组合连接的新型承插装配式墩,通过复合荷载作用下的拟静力试验对比了现浇(reinforced concrete,RC)、灌浆套筒(grouting and sleeve,GS)、承插口(socket with ultra-high performance concrete,SU)和结合套筒连接钢筋的新型承插(grouting sleeve and socket with ultra-high performance concrete,GSU)连接拼装桥墩的损伤机理和滞回性能,结合有限元模型重点讨论了承插口深度对滞回性能的影响。结果表明:4个构件的破坏模式都是以受弯破坏为主的弯扭破坏,其中SU构件出现了轻微拔起的现象,而对应的GSU构件并未出现该现象,与RC构件接近;各构件的剪力-墩顶位移骨架发展趋势比较一致,由于GSU构件纵向钢筋连续,具有更好的整体性能,其抗弯承载力与RC构件接近,且明显大于SU和GS构件,4个构件弯曲滞回耗能较为接近;承插口深度为1.0倍截面宽度的GSU构件抗扭承载力略高于RC构件,且明显大于其余装配式墩,GSU构件的扭转刚度、延性系数和耗能能力均大于其他3个墩;当承插口深度采用0.5倍构件截面宽度时,新型承插GSU构件的抗弯和抗扭承载力均略高于整体现浇构件,具有良好的抵抗压弯扭荷载的能力,可以实现浅承插口连接。研究结果可为压弯扭复合作用下装配式墩的应用提供试验依据。展开更多
基金Projects(51109084/E09070151308234/E08061) supported by the National Natural Science Foundation of China+1 种基金Project(2013J05079) supported by the Natural Science Foundation of Fujian Province,ChinaProject(Z012002) supported by the Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering(Institute of Rock and Soil Mechanics,Chinese Academy of Sciences),China
文摘Based on the fictitious soil pile model, the effect of sediment on the vertical dynamic impedance of rock-socketed pile with large diameter was theoretically studied by means of Laplace transform technique and impedance function transfer method. Firstly, the sediment under rock-socketed pile was assumed to be fictitious soil pile with the same sectional area. The Rayleigh-Love rode model was used to simulate the rock-socketed pile and the fictitious soil pile with the consideration of the lateral inertial effect of large-diameter pile. The layered surrounding soils and bedrock were modeled by the plane strain model. Then, by virtue of the initial conditions and boundary conditions of the soil pile system, the analytical solution of the vertical dynamic impedance at the head of rock-socketed pile was derived for the arbitrary excitation acting on the pile head. Lastly, based on the presented analytical solution, the effect of sediment properties, bedrock property and lateral inertial effect on the vertical dynamic impedance at rock-socketed pile head were investigated in detail. It is shown that the sediment properties have significant effect on the vertical dynamic impedance at the rock-socketed pile head. The ability of soil-pile system to resist dynamic vertical deformation is weakened with the increase of sediment thickness, but amplified with the increase of shear wave velocity of sediment. The ability of soil pile system to resist dynamic vertical deformation is amplified with the bedrock property improving, but the ability of soil-pile system to resist vertical vibration is weakened with the improvement of bedrock property.
文摘AIM:To determine whether the levator palpebrae superioris(LPS)/superior rectus(SR)muscle complex,can influence the position of the upper lid and fornix in acquired anophthalmic sockets.METHODS:This comparative non-randomized and non-interventional study included retrospective data of 21 patients with unilateral acquired anophthalmic sockets repaired with spheric implants.High-resolution computed tomography(CT)measurements of the LPM/SR muscle complex and clinical topographic position of the upper lid,superior and inferior fornix depth in primary gaze position were evaluated.Demographic data were presented as frequency and percentage proportions and quantitative variables comparing the socket measurements with the normal contralateral orbit was statistically analyzed using non-parametric tests considering P<0.05.RESULTS:The anophthalmic orbits had a significantly shorter LPS length(P=0.01)and significantly thicker SR(P=0.02)than the normal orbit.Lagophthalmos was present in anophthalmic sockets but not in normal orbits(P=0.002),while levator function was normal in both(P>0.05,all comparisons).The superior fornix depth was similar in the anophthalmic socket and the contralateral normal orbit(P=0.192)as well the inferior fornix depth(P=0.351).CONCLUSION:Acquired anophthalmic sockets repaired with spheric implants have shorter LPS,thicker SR,and more lagophthalmos than normal orbits.The relationship of the LPS and SR with other orbital structures,associated with passive or active forces acting in the final position of the lids and external ocular prosthesis should be further investigated.
文摘Piles socketed in soft rock were traditionally regarded as end bearing piles, and the loads transferred from superstructure were assumed in design to be shouldered totally by the piles. This paper was designated to deal with the interaction between the piles socketed in weak rock and surrounding soil through field measurement. The pile head reaction and ground pressure under piled raft foundation were monitored, respectively. The analysis of the data measured in situ shows the characteristics of the pile embedded in weak rock are similar to that of friction pile to some extent. The rock socketed pile, together with the surrounding soil, shoulders the weight of the superstructure. It is suggested that soil bearing should be considered in designing the soft rock socketed piles, which can make the design more economical.
基金support of Yapi Merkezi Construction and Industry Inc.,Istanbul,Turkey
文摘A new comprehensive set of data(n = 178) is compiled by adding a data set(n = 72) collected by Arioglu et al.(2007) to the data set(n = 106) presented in Rezazadeh and Eslami(2017). Then, the compiled data set is evaluated regardless of the variation in lithology/strength. The proposed empirical equation in this study comprises a wider range of uniaxial compressive strength(UCS)(0.15 MPa 〈 σ_(rc) 〈156 MPa) and various rock types. Rock mass cuttability index(RMCI) is correlated with shaft resistance(r_s) to predict the shaft resistance of rock-socketed piles. The prediction capacity of the RMCI versus r_s equation is also found to be in a fair good agreement with the presented data in Rezazadeh and Eslami(2017). Since the RMCI is a promising parameter in the prediction of shaft resistance, the researchers in the rock-socketed pile design area should consider this parameter in the further investigations.
文摘Semi-deep foundations socketed in rocks are considered to be a viable option for the foundations in the presence of heavy load imposed by high-rise structures, due to the low settlement and high bearing capacity. In the optimum design of semi-deep foundations, prediction of the shaft bearing capacity, rs, of foundations socketed in rocks is thus critically important. In this study, the unconfined compressive strength(UCS), qu, has been applied in order to investigate the shaft bearing capacity. For this, a database of 106 full-scale load tests is compiled with UCS values of surrounding rocks, in which 34 tests with rock quality designation(RQD), and 5 tests with rock mass rating(RMR). The bearing rocks for semi-deep foundations include limestone, mudstone, siltstone, shale, granite, tuff, granodiorite, claystone, sandstone, phyllite, schist, and greywacke. Using the database, the applicability and accuracy of the existing empirical methods are evaluated and new relations are derived between the shaft bearing capacity and UCS based on the types of rocks. Moreover, a general equation in case of unknown rock types is proposed and it is verified by another set of data. Since rock-socketed shafts are supported by rock mass(not intact rock), a reduction factor for the compressive strength is suggested and verified in which the effect of discontinuities is considered using the modified UCS, qu(modified), based upon RMR and RQD in order to take into account the effect of the rock mass properties.
文摘Fractures to the orbital walls and floor must be appropriately managed to avoid severe conditions.This results in particularly challenging anatomical reconstructions.The main issues are the implant’s proper shaping,placement,and orientation onto the eye socket.A new,customized implant-shaping mould has already been developed to shape patient-specific implants.However,it still does not address the implant positioning in the fractured orbital cavity.
文摘Introduction: Leukocyte and platelet-rich fibrin (L-PRF) is an emerging material in dentistry, however, there are controversies surrounding its effectiveness. Despite the amount of literature available, debates regarding its effect continue. This review aims to summarize and clarify the data surrounding the use of L-PRF in promoting the healing of extraction sockets, which may offer a better outcome for future treatments. Purpose: The purpose of this review is to evaluate the current literature on the use of L-PRF in promoting the healing of extraction sockets, and to provide a comprehensive overview of the available evidence. Methods: A comprehensive computer-based search of databases such as PubMed, Medline, and Cochrane Library was conducted. Results: The results of this review suggest that L-PRF has shown promise in promoting early healing of extraction sockets, but the evidence for its effectiveness over a longer period is limited. Conclusion: Although L-PRF has shown promising results in the early healing periods, its effectiveness over a longer healing period cannot be confirmed based on the available data. More clinical trials with standardized protocols and consistent measurement methods are needed to establish the role of L-PRF in enhancing the healing of extraction sockets.
文摘为明确并提升承插式拼装桥墩抵抗压弯扭等复合荷载的能力,提出了一种结合灌浆套筒和承插口组合连接的新型承插装配式墩,通过复合荷载作用下的拟静力试验对比了现浇(reinforced concrete,RC)、灌浆套筒(grouting and sleeve,GS)、承插口(socket with ultra-high performance concrete,SU)和结合套筒连接钢筋的新型承插(grouting sleeve and socket with ultra-high performance concrete,GSU)连接拼装桥墩的损伤机理和滞回性能,结合有限元模型重点讨论了承插口深度对滞回性能的影响。结果表明:4个构件的破坏模式都是以受弯破坏为主的弯扭破坏,其中SU构件出现了轻微拔起的现象,而对应的GSU构件并未出现该现象,与RC构件接近;各构件的剪力-墩顶位移骨架发展趋势比较一致,由于GSU构件纵向钢筋连续,具有更好的整体性能,其抗弯承载力与RC构件接近,且明显大于SU和GS构件,4个构件弯曲滞回耗能较为接近;承插口深度为1.0倍截面宽度的GSU构件抗扭承载力略高于RC构件,且明显大于其余装配式墩,GSU构件的扭转刚度、延性系数和耗能能力均大于其他3个墩;当承插口深度采用0.5倍构件截面宽度时,新型承插GSU构件的抗弯和抗扭承载力均略高于整体现浇构件,具有良好的抵抗压弯扭荷载的能力,可以实现浅承插口连接。研究结果可为压弯扭复合作用下装配式墩的应用提供试验依据。