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弥漫性子宫腺肌病病人PUSH术的加速康复外科路径构建
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作者 余颖娟 谢日华 《护理研究》 北大核心 2025年第10期1613-1619,共7页
目的:构建针对弥漫性子宫腺肌病病人的弥漫性子宫病变重建生育力手术(PUSH)的加速康复外科(ERAS)路径。方法:通过文献回顾、德尔菲法构建弥漫性子宫腺肌病病人PUSH术的ERAS路径。结果:2轮专家函询问卷回收率分别为100.00%和95.65%,专家... 目的:构建针对弥漫性子宫腺肌病病人的弥漫性子宫病变重建生育力手术(PUSH)的加速康复外科(ERAS)路径。方法:通过文献回顾、德尔菲法构建弥漫性子宫腺肌病病人PUSH术的ERAS路径。结果:2轮专家函询问卷回收率分别为100.00%和95.65%,专家权威系数均为0.88,二级指标的肯德尔和谐系数分别为0.249和0.259,三级指标的肯德尔和谐系数分别为0.209和0.241(均P<0.001)。最终形成的弥漫性子宫腺肌病病人PUSH术的ERAS路径包含7项一级指标、44项二级指标、76项三级指标。结论:构建的弥漫性子宫腺肌病病人PUSH术的ERAS路径具有科学性、可靠性、实用性。 展开更多
关键词 弥漫性子宫腺肌病 子宫重建 保留生育力 加速康复外科(ERAS) push 临床路径 德尔菲法 护理
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Therapeutic Efficacy of Yizhichan Pushing Manipulation on Qinggan Mingmu Acupoint in Combination with Pediatric Tuina for the Treatment of Pseudomyopia
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作者 Yuanyang ZHANG 《Medicinal Plant》 2025年第4期74-76,共3页
[Objectives]To investigate the therapeutic effects of combined treatment on children diagnosed with pseudomyopia,based on the theoretical framework that the liver is associated with eye health in traditional Chinese m... [Objectives]To investigate the therapeutic effects of combined treatment on children diagnosed with pseudomyopia,based on the theoretical framework that the liver is associated with eye health in traditional Chinese medicine.[Methods]A multicenter randomized controlled trial was conducted involving 100 children,with the treatment group consisting of 50 participants receiving a combined treatment,while the control group,also comprising 50 participants,received conventional tuina.In the treatment group,the Yizhichan Pushing Manipulation was applied at a frequency of 120 times/min and a strength of 0.5-1.0 kg,targeting acupoints such as Ganyu and Guangming.The alterations in naked eye visual acuity,diopter measurements,and ciliary muscle regulation function were compared between the two groups of children both prior to and following treatment,and the clinical efficacy was assessed.[Results]The treatment group demonstrated a statistically significant enhancement in visual acuity(1.74±0.49 lines vs.1.02±0.52 lines),diopter improvement(0.91±0.29 D vs.0.46±0.25 D),and overall efficiency(96%vs.78%)when compared to the control group(all P<0.01).[Conclusions]This combined treatment exerts a therapeutic effect through a dual mechanism that involves the regulation of liver meridian qi and blood,as well as the enhancement of ciliary muscle function.This approach merits further dissemination and application in the prevention and management of myopia in children. 展开更多
关键词 Qinggan Mingmu acupoint Yizhichan pushing Manipulation Pediatric tuina PSEUDOMYOPIA Therapeutic efficacy
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Big Push for Rural Revitalization in 2025
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作者 MA LI 《China Today》 2025年第4期60-62,共3页
Rural revitalization was a major focus during this year’s“two sessions.”THE drive to advance China’s all-around rural revitalization comprises advances in agriculture,revitalization of rural areas,and well-being o... Rural revitalization was a major focus during this year’s“two sessions.”THE drive to advance China’s all-around rural revitalization comprises advances in agriculture,revitalization of rural areas,and well-being of rural residents–the“three rural work,”as emphasized by Premier Li Qiang in the 2025 government work report. 展开更多
关键词 RURAL push RURAL
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Simulation of Fiber Pushing-out Test
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作者 张亚芳 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第6期965-969,共5页
The stress distribution on the failure progress of fiber pushed-out test was studied. A numerical program, developed by meso-damage mechanics, was adopted to simulate the whole failure process of interface debonding a... The stress distribution on the failure progress of fiber pushed-out test was studied. A numerical program, developed by meso-damage mechanics, was adopted to simulate the whole failure process of interface debonding and fiber pushing out. From the simulation, it can be concluded that, the interfacial stress on load side and support side is larger than other portions. Simultaneously, the shear stress in both sides becomes larger when thickness of sample reduces. Furthermore, when the diameter of fiber increases, the shear stress on load side is getting larger but in support side it is diminishing. On the other hand, changes of the support hole’s diameter only affect the interfacial shear stress on the support side. 展开更多
关键词 push out fiber reinforcement interface DEBONDING HETEROGENEOUS
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Finite Element Analysis of Push-Out Test of SiC Fiber Reinforced Titanium Matrix Composites 被引量:1
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作者 Yuan M N Yang Y Q Huang B Zhang R J 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2009年第A03期50-53,共4页
Based on the interphase layer model and the spring layer model, an improved interface model was developed to evaluate the interfacial shear strength of Titanium matrix composites(TMCs) and to analyze the effects of va... Based on the interphase layer model and the spring layer model, an improved interface model was developed to evaluate the interfacial shear strength of Titanium matrix composites(TMCs) and to analyze the effects of various parameters on the interfacial properties. The results showed that the improved interface model is more suitable for calculating the interfacial properties of SiC fiber reinforced titanium matrix composites. The interfacial shear strength of SiC/Timetal-834 predicted is 500 MPa. In addition, in order to better understand the interfacial properties of composites, some push out phenomenon were analyzed. 展开更多
关键词 复合材料 剪切强度 碳化硅纤维 物理性能
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Pull Breech out versus Push Impacted Head up in Emergency Cesarean Section: A Comparative Study 被引量:2
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作者 Hend S. Saleh Gamal A. Kassem +2 位作者 Mohamed El Said Mohamed Moustafa A. Ibrahiem Manal M. El Behery 《Open Journal of Obstetrics and Gynecology》 2014年第6期260-265,共6页
Objective: To compare maternal and fetal outcome associated with two methods Reverse breech extraction versus Head pushing to deliver the impacted fetal head in advanced labor requiring emergency Cesarean section. Met... Objective: To compare maternal and fetal outcome associated with two methods Reverse breech extraction versus Head pushing to deliver the impacted fetal head in advanced labor requiring emergency Cesarean section. Method: A prospective comparative study was conducted on 80 pregnant women at term with cephalic presentation in advanced labour, requiring emergency Cesarean Section. Reverse breech extraction technique (pull method) was used in 40 cases (group I) and pushing the head up through the vagina (“push” method) was tried in (group II) 40 cases. The maternal outcome was assessed by extension of the uterine Incision, bladder injury, intra and postoperative blood transfusion, Postpartum hemorrhage, wound infection and duration of hospital stay. Fetal outcome was Apgar score and admission to neonatal intensive care unit. Results: Extension of the uterine incision was significantly lower in women undergoing reverse breech extraction compared to cephalic delivery (20% versus 50%;p = 0.001). The mean operative time (pull group) was lower than that in the (push group) 59.7 ± 4.2, versus 75.2 ± 6.1 p = 0.001 and blood loss was significantly lower in the (pull group) than that in the (push group) 878 ± 67 ml, versus 1321 ± 57 ml, p = 0.001. No significant difference between groups regarding maternal and neonatal outcome. Conclusion: Reverse breech extraction (pull) is safer than pushing head up through vagina (push) for delivery of a deeply impacted fetal head in advanced labour sensitizing emergency Cesarean Section and is associated with the least maternal complications. 展开更多
关键词 Deeply Engaged HEAD OBSTRUCTED Labor CESAREAN Section Reverse BREECH Extraction HEAD push Method
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Failure characterization of fully grouted rock bolts under triaxial testing 被引量:2
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作者 Hadi Nourizadeh Ali Mirzaghorbanali +3 位作者 Mehdi Serati Elamin Mutaz Kevin McDougall Naj Aziz 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期778-789,共12页
Confining stresses serve as a pivotal determinant in shaping the behavior of grouted rock bolts.Nonetheless,prior investigations have oversimplified the three-dimensional stress state,primarily assuming hydrostatic st... Confining stresses serve as a pivotal determinant in shaping the behavior of grouted rock bolts.Nonetheless,prior investigations have oversimplified the three-dimensional stress state,primarily assuming hydrostatic stress conditions.Under these conditions,it is assumed that the intermediate principal stress(σ_(2))equals the minimum principal stress(σ_(3)).This assumption overlooks the potential variations in magnitudes of in situ stress conditions along all three directions near an underground opening where a rock bolt is installed.In this study,a series of push tests was meticulously conducted under triaxial conditions.These tests involved applying non-uniform confining stresses(σ_(2)≠σ_(3))to cubic specimens,aiming to unveil the previously overlooked influence of intermediate principal stresses on the strength properties of rock bolts.The results show that as the confining stresses increase from zero to higher levels,the pre-failure behavior changes from linear to nonlinear forms,resulting in an increase in initial stiffness from 2.08 kN/mm to 32.51 kN/mm.The load-displacement curves further illuminate distinct post-failure behavior at elevated levels of confining stresses,characterized by enhanced stiffness.Notably,the peak load capacity ranged from 27.9 kN to 46.5 kN as confining stresses advanced from σ_(2)=σ_(3)=0 to σ_(2)=20 MPa and σ_(3)=10 MPa.Additionally,the outcomes highlight an influence of confining stress on the lateral deformation of samples.Lower levels of confinement prompt overall dilation in lateral deformation,while higher confinements maintain a state of shrinkage.Furthermore,diverse failure modes have been identified,intricately tied to the arrangement of confining stresses.Lower confinements tend to induce a splitting mode of failure,whereas higher loads bring about a shift towards a pure interfacial shear-off and shear-crushed failure mechanism. 展开更多
关键词 Rock bolts Bolt-grout interface Bond strength push test Triaxial tests
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Effect of addition of chitosan to self-etching primer:antibacterial activity and push-out bond strength to radicular dentin
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作者 Shaymaa Elsaka Amr Elnaghy 《The Journal of Biomedical Research》 CAS 2012年第4期288-294,共7页
The purpose of this study was to evaluate the antibacterial activity of a modified self-etching primer incorporating chitosan and whether this modification affected the bond strength to radicular dentin.A modified sel... The purpose of this study was to evaluate the antibacterial activity of a modified self-etching primer incorporating chitosan and whether this modification affected the bond strength to radicular dentin.A modified self-etching primer was prepared by adding chitosan solutions at 0.03%,0.06%,0.12% and 0.25%(W/W) to RealSeal selfetching primer.RealSeal primer without chitosan was used as the control.The antibacterial activity of the modified self-etching primer was evaluated using the direct contact test against Enterococcus faecalis.The bonding ability of the RealSeal system to radicular dentin was evaluated using the push-out bond strength test.The modes of failure were examined under a stereomicroscope.Data were analyzed using analysis of variance(ANOVA) and Tukey’s test,with a P-value 〈 0.05 indicating statistical significance.The results showed that the antibacterial properties of the freshly prepared and aged modified self-etching primer incorporating chitosan exhibited potent antibacterial effect against Enterococcus faecalis compared with the unmodified primer.The RealSeal system with the aged modified self-etching primer incorporating chitosan showed no significant differences in the bond strength as compared with the control(P = 0.99).The findings suggest that modified self-etching primer incorporating chitosan is a promising antibacterial primer which does not adversely affect the bond strength of the RealSeal system to radicular dentin. 展开更多
关键词 Enterococcus faecalis antibacterial activity CHITOSAN push-out PRIMER radicular dentin
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Push-out Bond Strength of Self-adhesive Methacrylate Resin-based Sealers to Root Dentin
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作者 孙燕 李宇红 樊明文 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2014年第1期108-113,共6页
This study examined the adhesive strength of two self-adhesive methacrylate resin-based sealers(MetaSEAL and RealSeal SE) to root dentin and compared them with RealSeal and AH Plus in properties. A total of 48 extra... This study examined the adhesive strength of two self-adhesive methacrylate resin-based sealers(MetaSEAL and RealSeal SE) to root dentin and compared them with RealSeal and AH Plus in properties. A total of 48 extracted human single-rooted teeth were used to prepare the 0.9-mm thick longitudinal tooth slice(each per tooth). Standardized simulated canal spaces of uniform dimensions were prepared in the middle of radicular dentin. After treated with 5.25% sodium hypochlorite(NaOCl) and 17% EDTA, tooth slices were allocated randomly to four groups(n=12) in terms of different sealers used: MetaSEAL, RealSeal SE, RealSeal, and AH plus groups. The simulated canal spaces were obturated with different sealers in each group. There were 10 slabs with 20 simulated canal spaces(n=20) used in each group for push-out testing. The failure modes and the ultrastructures of fractured sealer-dentin interfaces were examined. The remaining 2 slabs in each group underwent partial demineralization for observation of the ultrastructure of resin tags. The results showed that the push-out bond strength was 12.01±4.66 MPa in MetaSEAL group, significantly higher than that in the other three groups(P0.05). Moreover, no statistically significant differences were noted in the push-out bond strength between RealSeal SE(5.43±3.68 MPa) and AH Plus(7.34±2.83 MPa) groups and between RealSeal SE and RealSeal(2.93±1.76 MPa) groups(P0.05). Mixed failures were predominant in the fractured sealer-dentin interfaces in MetaSEAL and AH Plus groups, while adhesive failures were frequently seen in RealSeal SE and RealSeal groups. In conclusion, after complete removal of the smear layer, MetaSEAL showed superior bond ability to root dentin. The RealSeal SE is applicable in clinical practice, with its adhesive strength similar to that of AH Plus. The self-adhesive methacrylate resin-based sealer holds promise for use in endodontic treatment. 展开更多
关键词 endodontic sealer push-out bond strength adhesive interface raidicular dentin
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A Push Motivation Model of Filipino Youth Travel
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作者 Maria Victoria P. Tibon 《Journal of Modern Accounting and Auditing》 2012年第9期1392-1397,共6页
Youth travel is of special interest, because a considerable number of Filipinos belong to the youth population. By focusing on the youth market, tourism enterprises can maximize considerable business opportunities. Th... Youth travel is of special interest, because a considerable number of Filipinos belong to the youth population. By focusing on the youth market, tourism enterprises can maximize considerable business opportunities. This study, by using several known motivations and activity preferences of travelers, identified major push motives of young students. Factor analysis of responses from 117 students revealed four push motives, namely, nature and wellness, education, meeting people and relaxation, and unique experience. Young students have been found to travel from the hustle and bustle of city life and contemplate nature, to learn, rest, and interact with other people, and to acquire different kinds of experiences. 展开更多
关键词 tourism youth travel push motivation young Filipino travelers
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PUSH技术在智能电表中的应用 被引量:1
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作者 牛延谋 杨招勇 +1 位作者 洪晶晶 徐京生 《电工技术》 2024年第8期148-149,154,共3页
介绍智能电表推送(PUSH)技术的基本原理和解决方案,并对不同解决方案进行分析和比较,最后指出应用推送技术时采用的最优化方案,并深入研究数据传输可靠性和大批量数据传输时通道堵塞技术问题,提出解决方案。
关键词 push技术 智能电表 DLMS规约
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Zhejiang’s Push for Higher Efficiency in Government Services
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作者 CHEN HUIXI LIU NIAN 《China Today》 2024年第8期35-37,共3页
A band of programs have been implemented in Zhejiang with the aim of streamlining administrative processes in the public interest.ENHANCING executive efficiency remains one of the priorities of east China’s Zhejiang ... A band of programs have been implemented in Zhejiang with the aim of streamlining administrative processes in the public interest.ENHANCING executive efficiency remains one of the priorities of east China’s Zhejiang Province,a coastal economic powerhouse.Over the past decade,it has launched a series of reforms to improve government performance and to better serve businesses and residents. 展开更多
关键词 SERVICES push EFFICIENCY
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CHINA’S PUSH FOR UNIFIED NATIONAL MARKET BRINGS NEW OPPORTUNITIES
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作者 Tom Fowdy 《China Report ASEAN》 2024年第2期79-79,共1页
In recent years,China has implemented measures to advance the building of a unified national market,aiming to boost domestic demand and consolidate the foundations of its economic recovery.In March 2022,the Chinese go... In recent years,China has implemented measures to advance the building of a unified national market,aiming to boost domestic demand and consolidate the foundations of its economic recovery.In March 2022,the Chinese government issued a guideline on accelerating the construction of a unified national market.The issue was also a focus at the annual Central Economic Work Conference held in December 2023. 展开更多
关键词 UNIFIED push measures
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Further Studies of the Cap Pushing Response in Honey Bees (Apis mellifera)
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作者 Riley J. Wincheski Kiri Li N. Stauch +3 位作者 Laura M. Grossner Maya B. Zepeda James W. Grice Charles I. Abramson 《Natural Science》 2024年第5期45-64,共20页
The Cap Pushing Response (CPR) is a free-flying technique used to study learning and memory in honey bees (Apis mellifera). The series of experiments outlined in this paper aimed to test whether honey bees exhibit the... The Cap Pushing Response (CPR) is a free-flying technique used to study learning and memory in honey bees (Apis mellifera). The series of experiments outlined in this paper aimed to test whether honey bees exhibit the cognitive concept of “expectancy” utilizing the CPR in a weight differentiation paradigm. Five previous experiments in our laboratory have explored whether the concept of expectancy can account for honey bee performance and have all failed to support the cognitive interpretation. The first experiment examined if bees could differentiate between the two caps in the amount of force they used to push the cap and the distance the cap was pushed when the caps were presented one at a time. The second experiment explored cap weight preference by presenting bees with a choice between the two caps. The third and fourth experiments tested the bee’s ability to expect reward or punishment based on cap weight. Results revealed that bees were found to have a strong preference for the light cap and therefore were not able to expect reward or punishment based on cap weight. These experiments contribute to the debate on whether bees have “cognitive” representations and continue to support the behaviorist interpretation. 展开更多
关键词 Apis mellifera Cap pushing Response COGNITION LEARNING
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Shelton Vision pushes the needle on Al-assisted quality control
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《China Textile》 2024年第1期40-41,共2页
MANCHESTER,UK-Having successfully demonstrated its WebSpector automated fabric inspection system detecting faults on camouflage fabrics at speeds of up to 100metres a minute during ITMA 2023,BTMA member Shelton Vision... MANCHESTER,UK-Having successfully demonstrated its WebSpector automated fabric inspection system detecting faults on camouflage fabrics at speeds of up to 100metres a minute during ITMA 2023,BTMA member Shelton Vision has secured an unprecedented number of new orders in many fields of the textile industry.The company has subsequently been recruiting additional staff in order to beef up its operations to meet delivery times and to grow capacity for the ongoing increased demand. 展开更多
关键词 NEEDLE INSPECTION push
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基于多因素的钢管混凝土界面黏结性能分析与强度预测模型评价
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作者 赵轩 杨晨 +5 位作者 胡朝晖 李贤 聂影 刘俊 廖栩 刘西光 《建筑钢结构进展》 北大核心 2025年第11期75-87,共13页
为研究混凝土骨料粒径、钢管径厚比、长径比、钢管内壁粗糙程度与疲劳荷载对钢管混凝土(concrete-filled steel tube,CFST)界面黏结性能的影响,共设计了9个试件进行推出试验,通过荷载-滑移曲线以及推出试验过程中钢管外表面纵向应变与... 为研究混凝土骨料粒径、钢管径厚比、长径比、钢管内壁粗糙程度与疲劳荷载对钢管混凝土(concrete-filled steel tube,CFST)界面黏结性能的影响,共设计了9个试件进行推出试验,通过荷载-滑移曲线以及推出试验过程中钢管外表面纵向应变与环向应变的分布情况,分析了CFST界面黏结强度与黏结刚度,研究结果表明:试件的荷载-滑移曲线均呈现出自由端的位移滞后于加载端的位移的现象,且随着加载的进行,自由端的位移增量逐渐与加载端的位移增量同步;CFST柱的黏结性能随钢管径厚比的增大而减小、随钢管内壁粗糙程度的降低而减小、随长径比的增大而减小;细骨料混凝土与疲劳作用均会降低CFST柱的黏结性能;钢管外表面纵向应变随距加载端距离的增大而增大,且黏结破坏后,荷载在钢管上呈现不均匀传递的现象;文中对现有的CFST黏结强度模型与试验数据进行了整理,并分析其吻合度,随后基于统计分析,以混凝土强度、CFST柱径厚比、长径比为参数,回归拟合出一个新的黏结强度计算公式,该公式计算结果与实际数据吻合较好。 展开更多
关键词 钢管混凝土 推出试验 界面性能 黏结滑移 黏结强度模型
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预埋型螺栓连接件的可拆换性能研究
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作者 门进杰 杜天宇 +3 位作者 李家富 张谦 王家琛 MUDASSAR Ali 《地震工程与工程振动》 北大核心 2025年第2期86-96,共11页
文中提出了一种预埋型螺栓连接件,通过设置预埋钢块和螺栓锥套,减少受载时混凝土和钢梁的损伤,实现组合梁的可拆换。设计制作了8组试件,推出试验后拆卸,并对拆卸后的组件重新使用并加载,分析其可拆换性能。探讨了螺栓直径、螺栓强度、有... 文中提出了一种预埋型螺栓连接件,通过设置预埋钢块和螺栓锥套,减少受载时混凝土和钢梁的损伤,实现组合梁的可拆换。设计制作了8组试件,推出试验后拆卸,并对拆卸后的组件重新使用并加载,分析其可拆换性能。探讨了螺栓直径、螺栓强度、有无T形钢块和预埋钢块外径等因素的影响规律。研究结果表明:试件破坏时螺栓剪断或混凝土压溃;8组试件加载后均可快速拆卸;拆卸后的钢梁和T形钢块可多次重复使用;加载后处于无损伤和轻微损伤状态的混凝土板可重复使用2次以上且试件的抗剪性能基本不变;处于损伤状态的混凝土板可重复使用1次,但试件的抗剪性能降低;处于严重损伤状态的混凝土板不可重复使用。此外,预埋型螺栓连接件具有良好的抗掀起性能;螺栓直径或强度的增加,试件的承载力和混凝土板的损伤增加;预埋钢块外径增加,试件的承载力不变,但混凝土板的损伤减少;有无T形钢块对试件的承载力基本没有影响,但可以提高可拆换性能。最后提出了混凝土板局部损伤系数η作为可拆换性能控制指标,当η在0.5左右时可拆换状态较好。 展开更多
关键词 组合梁 预埋型螺栓连接件 推出试验 可拆换性能 可拆换性能指标
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预制桥墩与承台间承插式连接直剪性能试验
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作者 姜海波 谢思源 +3 位作者 李明毅 陈明珠 周治国 孙晓立 《长安大学学报(自然科学版)》 北大核心 2025年第2期60-74,共15页
为探究不同参数对承插式连接直剪承载力的影响,以承插式连接处灌浆料类型、界面类型、接缝宽度、键齿数量为研究对象,基于试验与有限元模型研究承插式连接直剪性能的影响机制;设计12个承插式连接推出试件,采用双面剪切方式完成承插式连... 为探究不同参数对承插式连接直剪承载力的影响,以承插式连接处灌浆料类型、界面类型、接缝宽度、键齿数量为研究对象,基于试验与有限元模型研究承插式连接直剪性能的影响机制;设计12个承插式连接推出试件,采用双面剪切方式完成承插式连接直剪性能试验,并获得推出试验的开裂荷载、裂缝分布和破坏模式。研究结果表明:相较于键齿剪力槽构件,波形钢管剪力槽构件的直剪承载力下降了24.9%~46.4%,表明波形钢管剪力槽构造的界面连接性能不利于结构整体性;制备的3种C90高性能灌浆料对键齿剪力槽构件的直剪承载力影响不大,但影响了波形钢管剪力槽构件的裂缝发展程度;采用钢纤维混凝土(SFRC)作为窄缝灌浆料时试件的抗弯折性能更好,有利于抑制窄缝裂缝发展;对于键齿剪力槽构件,接缝宽度从5 cm增加到10 cm时,其直剪承载力下降了12.2%~36.5%,键齿数量从单键齿增加到双键齿时,直剪承载力提升了19.4%~47.6%;将单键齿增加为多键齿后,局部推出有限元模型扩展分析所得试件直剪承载力提高了51.45%~118.13%,界面类型从键齿剪力槽改变为波形钢管剪力槽后,试件直剪承载力降低了12.06%~33.58%;采用美国国家公路与运输协会(AASHTO)规范计算所得试件直剪承载力平均值比试验值低45.9%,而采用日本土木工程师学会(JSCE)规范计算所得试件直剪承载力平均值比试验值高11.3%,说明AASHTO规范的计算值偏保守,而JSCE规范的计算值更贴近试验值。 展开更多
关键词 桥梁工程 直剪性能 推出试验 湿接缝 承插式连接
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钢管碱激发混凝土叠合柱黏结滑移性能研究
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作者 任志刚 许天恩 +1 位作者 李旗 冯逸轩 《建筑科学与工程学报》 北大核心 2025年第6期77-86,共10页
为研究钢管碱激发混凝土叠合柱界面黏结性能,对10个钢管碱激发混凝土叠合柱试件进行推出试验,分析钢纤维体积率、含管率、体积配箍率对钢管碱激发混凝土叠合柱界面黏结性能的影响。试验加载过程中,仔细观察试件的裂缝发展和破坏形态,并... 为研究钢管碱激发混凝土叠合柱界面黏结性能,对10个钢管碱激发混凝土叠合柱试件进行推出试验,分析钢纤维体积率、含管率、体积配箍率对钢管碱激发混凝土叠合柱界面黏结性能的影响。试验加载过程中,仔细观察试件的裂缝发展和破坏形态,并得到了试件的荷载-滑移曲线,通过对荷载-滑移曲线分析和归类,总结出具有典型形式的荷载-滑移曲线。深入分析了各变化参数对特征黏结强度的影响规律,运用灰色关联理论建立了特征黏结强度计算式。结果表明:推出试验后的试件整体较为完整,外部混凝土表面无明显裂缝,加载端面混凝土有一定损伤,荷载-滑移典型曲线分为3类;特征黏结强度随钢纤维体积率和体积配箍率的增加而增加;残余黏结强度随含管率的增加而减小,存在最佳截面尺寸范围,使极限黏结强度达到最大值;灰色关联理论能够较好地反映特征黏结强度与各影响因素之间的关系,其中钢纤维体积率与极限黏结强度相关性最强,含管率与残余黏结强度相关性最强。 展开更多
关键词 碱激发混凝土 叠合柱 荷载-滑移曲线 推出试验 黏结性能
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波形腹板钢纤维PEC柱界面黏结滑移性能试验研究
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作者 王威 唐家璇 +4 位作者 李昱 柳国良 唐新耀 邱程宣 钱源明 《湖南大学学报(自然科学版)》 北大核心 2025年第9期91-102,共12页
PEC柱具有稳定性好、预制化程度高的优点,在其中加入钢纤维可有效抑制混凝土裂纹的发展.以锚固长度和钢纤维掺量为变量,设计了8个波形腹板钢纤维PEC柱试件并进行推出试验,研究了其界面黏结滑移性能.结果表明:钢纤维混凝土试件在荷载下... PEC柱具有稳定性好、预制化程度高的优点,在其中加入钢纤维可有效抑制混凝土裂纹的发展.以锚固长度和钢纤维掺量为变量,设计了8个波形腹板钢纤维PEC柱试件并进行推出试验,研究了其界面黏结滑移性能.结果表明:钢纤维混凝土试件在荷载下降段界面裂纹贯通,试件破坏模式均为界面自然黏结力失效破坏;当钢纤维掺量一定、锚固长度为650 mm时,界面黏结性能最佳;在混凝土中加入钢纤维可提升黏结性能,随着钢纤维掺量增大,初始滑移荷载与初始强度随之增大,极限荷载先减后增,当钢纤维掺量为1.5%时,极限强度达到最小值而残余强度达到最大值;钢板翼缘应变在荷载上升段随锚固长度近似呈指数分布,波形腹板应变呈波浪形;通过线性回归拟合得出试件特征黏结强度的计算式,将计算值与试验值对比,发现误差较小,可为波形腹板钢纤维PEC柱的承载力设计及应用提供参考. 展开更多
关键词 波形腹板PEC柱 钢纤维 黏结滑移 推出试验 等效应变 黏结强度
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