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Altered thermal sensitivity in facial skin in chronic whiplash-associated disorders 被引量:1
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作者 Birgitta Hggman-Henrikson Ewa Lampa Erik Nordh 《International Journal of Oral Science》 SCIE CAS CSCD 2013年第3期150-154,共5页
There is a close functional relationship between the jaw and neck regions and it has been suggested that trigeminal sensory impairment can follow whiplash injury.Inclusion of manageable routines for valid assessment o... There is a close functional relationship between the jaw and neck regions and it has been suggested that trigeminal sensory impairment can follow whiplash injury.Inclusion of manageable routines for valid assessment of the facial sensory capacity is thus needed for comprehensive evaluations of patients exposed to such trauma.The present study investigated facial thermal thresholds in patients with chronic whiplash-associated disorders(WADs)with both a qualitative method and quantitative sensory testing(QST).Ten women with pain and dysfunction following a whiplash injury were compared to 10 healthy age-matched women.Thermal detection thresholds were assessed by qualitative chair-side testing and by QST according to the method-of-limits.Seven test sites in the facial skin(overlying each trigeminal branch bilaterally,and the midpoint of the chin)were examined.The detection warm and cold thresholds were defined as the mean values of 10 individual thresholds.For the WAD patients,the qualitative assessment demonstrated both reduced and increased sensitivity compared to the healthy,whereas QST systematically showed significantly higher detection thresholds(i.e.,decreased sensitivity)for both cold and warm stimuli.For the individuals who were assessed as having increased sensitivity in the qualitative assessment,the QST displayed either normal or higher thresholds,i.e.,decreased sensitivity.The results suggest that QST is more sensitive for detecting thermal sensory disturbances in the face than a qualitative method.The impaired thermal sensitivity among the patients corroborates the notion of altered thermal detection capacity induced by WAD-related pain. 展开更多
关键词 JAW NECK quantitative sensory testing thermal thresholds TRIGEMINAL whiplash injury
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Correlation between expectations of recovery and injury severity perception in whiplash-associated disorders 被引量:3
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作者 Robert FERRARI Deon LOUW 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2011年第8期683-686,共4页
Objective:To assess the correlation between expectations of recovery and whiplash patients' perceptions of injury severity using a simplified instrument.Expectations of recovery have been shown to predict rate of ... Objective:To assess the correlation between expectations of recovery and whiplash patients' perceptions of injury severity using a simplified instrument.Expectations of recovery have been shown to predict rate of recovery from whiplash injury in population-based studies.The perception of having more severe pathology or more ominous diagnostic labels has also been associated with a worse prognosis.Methods:Consecutive patients with whiplash-associated disorder grade 1 or 2,presenting in the acute stage to a primary care centre,were asked "do you think that your injury will…" with response options "get better soon;get better slowly;never get better;don't know." Injury severity perception (ISP) was measured with a numerical rating scale which ranged from 0-10,on which subjects were asked to rate how severe (in terms of damage) they thought their injury was.The anchors were labeled "no damage" (0) and "severe,and maybe permanent damage" (10).The primary outcome measure was the correlation between the subject's ISP score and expectation of recovery.Results:A total of 94 subjects (34 males,60 females,and mean age (40.6±10.0) years,range 19-60 years) were included.The initial responses to expectation of recovery were:get better soon (29/94);get better slowly (22/94);never get better (11/94);don't know (32/94).The mean ISP score was 4.9±1.7 (range 2-9 out of 10).There was a high correlation between expectations and ISP scores (Spearman's rank correlation coefficient 0.68).Those who expected to recover soon and those who expected to get better slowly had the lowest ISP scores.Conclusions:The more slowly whiplash patients expect to recover,or the less sure they are of recovery,the more severe their initial perceptions of injury. 展开更多
关键词 whiplash-associated disorders (WAD) Expectations of recovery Injury severity perception (ISP)
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Development of a symptom expectation questionnaire for whiplash injury
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作者 Robert Ferrari Deon Louw 《Journal of Sport and Health Science》 SCIE 2012年第3期174-177,195,共5页
Background:Expectations and beliefs appear to be important predictors of outcome following whiplash injury.Instruments for measuring these expectations in the general population have not been well studied.The objectiv... Background:Expectations and beliefs appear to be important predictors of outcome following whiplash injury.Instruments for measuring these expectations in the general population have not been well studied.The objective of this study was to develop a simple symptom expectation questionnaire for whiplash injury for use in future research studies. Methods:An existing database of 179 injury-naive subjects who completed a 56-item checklist of expected symptoms for whiplash injury was analyzed to determine which items could correctly identify an a priori case definition of an expecter(a subject who expected at least one of these symptoms would remain chronic following whiplash injury).A total of seven of the 56 items were found to be discriminatory.The identified, discriminatory items were then tested in additional subject groups against the original questionnaire. Results:From the original database of 179 subjects completing a 56-item symptom expectation checklist,119 expected at least one of the 56 symptoms would be chronic following whiplash injury.The 119 expecters.however,all chose at least one of seven items:headache,anxious or worried,depressed,neck pain,problems sleeping,back pain,or jaw pain.Using these seven items,in two new groups of subjects given the 56- item symptom expectation checklist and then a new shortened(7-item) symptom expectation checklist one week later(and the same done for another group of 100 subjects in reverse order),all those who endorsed one of the 56 symptoms as likely to be chronic following whiplash injury (expecters) could also be identified on the 7-item checklist. Conclusion:A shortened(7-item) symptom expectation checklist of commonly reported symptoms following whiplash injury(headache, anxious or worried,depressed,neck pain,problems sleeping,back pain,and jaw pain) correctly identifies subjects who expect at least one symptom will be chronic following minor head injury(i.e.,an expecter).This shortened(7-item) symptom expectation checklist can be used in future population-based studies to understand the prevalence of belief patterns and expectations for whiplash injury. 展开更多
关键词 EXPECTATION QUESTIONNAIRE SYMPTOMS whiplash injuries
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Evaluation of the test-retest repeatability of the Injury Severity Perception score in patients with acute whiplash-associated disorder
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作者 Robert Ferrari 《Journal of Sport and Health Science》 SCIE 2015年第4期396-398,共3页
Objective: To determine the test retest repeatability of the Injttry Severity Perception (ISP) score in participants with acute whiplash-associated disorders (WADs). Methods: Consecutive patients with WAD, prese... Objective: To determine the test retest repeatability of the Injttry Severity Perception (ISP) score in participants with acute whiplash-associated disorders (WADs). Methods: Consecutive patients with WAD, presenting in the acute stage to a primary care center, were asked to complete the 1SP score. ISP was measured with a numerical rating scale that ranged from 0 to 10, on which subjects were asked to rate how severe (in terms of damage) they thought their injury was. The anchors were labeled "no damage" (0) and "severe, and maybe permanent damage" (10). The ISP questionnaire was administered to the participants at the time of recruitment and again 7 days later. Repeatability was evaluated by calculating percentage agreement and Cohen kappa statistic between the two time points of measurement. Results: A total of 94 subjects (34 males, 60 females, mean age 40.6 ± 10.0 years, range 19-60 years) were included. The mean 1SP score was 4.9 ± 1.7 (range 2-9 out of 10) at the time of recruitment and 5.1 ± 2.1 (range 2-9 out of 10) 7 days later. The percentage agreement between the two repeat measures of the ISP was 86% and the kappa coefficient was 0.79. Conclusion: This study suggests that the test-retest repeatability for the ISP is high and that it is thus likely to have a low risk of classification bias in prognostic studies. The ISP likely has adequate reliability for use in epidemiological research of WADs. 展开更多
关键词 INJURY Injury Severity Perception PAIN whiplash injury
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Correlation between self-reported recovery and central sensitization in whiplash patients
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作者 Robert Ferrari 《Journal of Sport and Health Science》 SCIE 2012年第1期61-64,共4页
Central sensitization has been associated with chronic pain in whiplash patients.Methods:Consecutive whiplash patients were assessed at 3 months post-whiplash injury with the brachial plexus provocation test(BPPT)as a... Central sensitization has been associated with chronic pain in whiplash patients.Methods:Consecutive whiplash patients were assessed at 3 months post-whiplash injury with the brachial plexus provocation test(BPPT)as a sign of central sensitization.Self-reported recovery was assessed by the response to the question ‘Do you feel you have recovered fully from your accident injuries?'Results:Sixty-nine subjects(32 males,37 females,age 37.5±13.0 years(mean±SD),range 18-71)were included.Of these,34 reported a lack of recovery,and 35 reported recovery at 3 months post-injury.The mean BPPT elbow extension(from 180°)was 41.5±23.0°,and the mean VAS score for the BPPT was 2.2 ± 1.2(out of 10).Those who reported recovery had a mean BPPT elbow extension angle of 25.1±15.8 while those who did not report recovery had a mean BPPT angle of 58.4 ± 15.9(P<0.05).The visual analogue scale(VAS)score for recovered subjects was 1.8 ± 1.1 and 2.7 ± 1.1(P<0.05)for non-recovered.There was a moderate correlation between self-reported recovery and BPPT elbow extension angle(-0.44)and a lower correlation between self-reported recovery and VAS score(-0.30).Conclusion:Self-reported recovery correlates well with a lower likelihood of signs of central sensitization.Copyright(c)2012,Shanghai University of Sport.Production and hosting by Elsevier B.V.All rights reserved. 展开更多
关键词 Brachial plexus provocation test Central sensitization Self-reported recovery whiplash injury
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Assessment of the Biological Damage in Whiplash Syndrome: Role of Digital Infrared Thermal Imaging (DITI) and Ultrasonography (US)
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作者 Gian Carlo Parenti Enzo Gualtieri +2 位作者 Francesco Fontana Aleardo Benelli Fabrizio Albarello 《Open Journal of Radiology》 2013年第4期222-230,共9页
Objectives: To compare DITI vs US in a cohort of patients with whiplash syndrome for assessing soft tissues injuries of the cervical and dorsal spine. Methods: 70 patients presenting to clinic with traumatic cervical ... Objectives: To compare DITI vs US in a cohort of patients with whiplash syndrome for assessing soft tissues injuries of the cervical and dorsal spine. Methods: 70 patients presenting to clinic with traumatic cervical and/or dorsal spine injury and with a clinical diagnosis of whiplash syndrome underwent both DITI (AVIO TVS 2000) and US (GE Logic 5) of the following muscles: sternocleidomastoid, splenius, trapezius, longus colli and paravertebral muscles. DITI considered positive in the region with the most altered temperature among the injured area examinated (normal range 0℃ - 0.8℃). US valued the cervical and dorsal region with a comparative examination of the soft tissues. The images taken with DITI were compared with the clinical and the sonographic outcomes respectively. US and DITI were considered a) congruent whether both had a positive outcome for the same muscle clinically injured;b) not congruent whether one of the two instruments had a different outcome then the clinical evidence. Wilcoxon paired test was used for statistical analysis. Results: DITI and US matched 153 of 233 (65%) injured muscles. The association between DITI and US in the evaluation of the injured muscles was statistically significant for the following muscles: left trapezius (p Conclusions: According to our preliminary study, DITI and US were both helpful for assessing soft tissues injuries in patients with whiplash syndrome, defining the extent of the biologic damage for a correct clinical-therapeutical management. 展开更多
关键词 whiplash SYNDROME DIGITAL Infrared Termography Imaging Ultrasongraphy LEGAL MEDICINE
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Predictive Factors for Persistent Pain and Poor Recovery of Health Status 1 Year after Whiplash Injury (Quebec Grade 1 and 2): Results from the ESPARR Cohort
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作者 Inès Khati Laetitia Chossegros +4 位作者 Pierrette Charnay Hélène Tardy Anne-Laure Perrine Bernard Laumon Martine Hours 《Pain Studies and Treatment》 2014年第2期36-49,共14页
Background: A large number of studies have addressed whiplash injury, and many meta-analyses have sought to highlight chronicity factors;the implicated processes, however, remain a matter of debate. The present study ... Background: A large number of studies have addressed whiplash injury, and many meta-analyses have sought to highlight chronicity factors;the implicated processes, however, remain a matter of debate. The present study used data from the ESPARR cohort (an on-going prospective study of a representative cohort of road accident victims in the Rh?ne administrative département of France). The objectives were to describe the consequences of whiplash injury and to determine prognostic factors for poor recovery and persistent pain at 1 year post-accident. Methods: The cohort included 255 “pure” whiplash victims, 173 of whom responded to the 1-year follow-up questionnaire. Correlations between explanatory variables and health and pain status were explored by modified Poisson regression to provide adjusted relative risk (RR) values. Results: Half of the victims had not fully recovered health status by 1 year. The main factor associated with non-recovery was pain (RR = 1.3;1.0-1.7). A birth in the family preceding the accident emerged as another factor (RR=1.5;1.2-1.9). Victims responsible for their accident were twice as likely to report being free of pain as those not responsible (RR = 0.5;0.3-0.8). No correlation emerged with accident-related characteristics or PTSD. Conclusions: The present results extend our understand- ing of whiplash injury. Residual pain is the fundamental factor causing whiplash victims to feel that they have not recovered good health. Our findings suggest this may be bound up with physical factors (gender susceptibility);external factors such as having to carry weights (such as a baby) and with perceiving oneself as a victim are not incompatible with this hypothesis. 展开更多
关键词 whiplash One Year-Follow-up Recovered Health PAIN Predictive Factor
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Effect of a pain diary use on recovery from acute whiplash injury: a cohort study
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作者 Robert FERRARI Deon LOUW 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第11期1049-1053,共5页
Previously,it was shown that the use of a symptom diary for two weeks,even in generally healthy subjects,results in increased recall of daily symptoms and increased perception of symptom severity(Ferrari and Russell,2... Previously,it was shown that the use of a symptom diary for two weeks,even in generally healthy subjects,results in increased recall of daily symptoms and increased perception of symptom severity(Ferrari and Russell,2010).In that study,generally healthy female subjects were asked to recall symptoms experienced in the previous two weeks,after keeping a symptom diary for two weeks,while a control group was asked to recall symptoms experienced in the previous two weeks without having kept a symptom diary.While both groups had 展开更多
关键词 a cohort study Effect of a pain diary use on recovery from acute whiplash injury
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New Concept of Whiplash Injuries Rehabilitation
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作者 Piotr Godek Michal Guzek Jakub Przychodzeń 《Journal of Human Physiology》 2021年第1期11-19,共9页
Whiplash injuries are a global health problem and a significant financial burden for both health care systems,and insurance providers.The diverse symptomatology after whiplash injury both in the somatic,emotional and ... Whiplash injuries are a global health problem and a significant financial burden for both health care systems,and insurance providers.The diverse symptomatology after whiplash injury both in the somatic,emotional and behavioral sphere prompted separation of the Whiplash Associated Disorders(WAD)as a separate category of diseases.The exact mechanism of whiplash injury is still under debate and theories explaining pathogenesis of WAD are very diverse ranging from purely biomechanical to neurophysiological,emphasizing central sensitization but the core disability seems to be strictly connected to somatosensory dysfunction.As a result,the optimal algorithm of rehabilitation has not been established and data published in the current literature on effectiveness of such algorithms are inconsistent.Based on the presented here of Head Neutral Reference Point(HNRP),the objective of central desensitization is to restore valid somatosensory output from Cranio-cervical Junction(CCJ).This new concept of rehabilitation after whiplash presented here is based on clinical observations and is supported by initial results. 展开更多
关键词 whiplash injuries REHABILITATION Somatosensory disorder Craniocervical injury Pain management
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Postmortem MSCT Diagnosis of Whiplash Injuries in a Traffic Accident:A Case Report and Review of the Literature 被引量:3
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作者 CHEN Min HUANG Ping +7 位作者 WAN Lei ZHANG Jian -hua LIU Ning -guo ZOU Dong -hua LI Zheng-dong SHAO Yu QIN Zhi-qiang CHEN Yi-jiu 《法医学杂志》 CAS CSCD 2014年第2期148-150,共3页
A 45-year-old male car driver died in a traffic accident of four cars rear-end collision on the highway.He was found to have died after a respiratory and cardiac arrest at the scene.No sign of skin injuries was observ... A 45-year-old male car driver died in a traffic accident of four cars rear-end collision on the highway.He was found to have died after a respiratory and cardiac arrest at the scene.No sign of skin injuries was observed from the external inspection.The autopsy was not permitted by the family members because of the local culture.Multislice computed tomography(MSCT)was applied to the current case,showing dislocation of C3~4cervical vertebrae withⅡdegree,C4vertebral plate fractures,and spinal stenosis.Post-mortem MSCT confirmed the diagnosis as whiplash injuries.MSCT was verified to be effective in showing the severity of whiplash injuries,thus providing certain objective evidence for medicolegal expertise. 展开更多
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Biomechanics of whiplash injury 被引量:1
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《Chinese Journal of Traumatology》 CAS 2009年第5期-,共10页
Despite a large number of rear-end collisions on the road and a high frequency of whiplash injuries reported, the mechanism of whiplash injuries is not completely understood. One of the reasons is that the injury is n... Despite a large number of rear-end collisions on the road and a high frequency of whiplash injuries reported, the mechanism of whiplash injuries is not completely understood. One of the reasons is that the injury is not necessarily accompanied by obvious tissue damage detectable by X-ray or MRI. An extensive series of biomechanics studies, including injury epidemiology, neck kinematics,facet capsule ligament mechanics, injury mechanisms and injury criteria, were undertaken to help elucidate these whiplash injury mechanisms and gain a better understanding of cervical facet pain. These studies provide the following evidences to help explain the mechanisms of the whiplash injury: (1) Whiplash injuries are generally considered to be a soft tissue injury of the neck with symptoms such as neck pain and stiffness, shoulder weakness, dizziness, headache and memory loss, etc. (2) Based on kinematical studies on the cadaver and volunteers, there are three distinct periods that have the potential to cause injury to the neck. In the first stage, flexural deformation of the neck is observed along with a loss of cervical lordosis; in the second stage, the cervical spine assumes an S-shaped curve as the lower vertebrae begin to extend and gradually cause the upper vertebrae to extend; during the final stage, the entire neck is extended due to the extension moments at both ends. (3)The in vivo environment afforded by rodent models of injury offers particular utility for linking mechanics, nociception and behavioral outcomes. Experimental findings have examined strains across the facet joint as a mechanism of whiplash injury, and suggested a capsular strain threshold or a vertebral distraction threshold for whiplash-related injury,potentially producing neck pain. (4) Injuries to the facet capsule region of the neck are a major source of post-crash pain. There are several hypotheses on how whiplash-associated injury may occur and three of these injuries are related to strains within the facet capsule connected with events early in the impact. (5) There are several possible injury criteria to correlate with the duration of symptoms during reconstructions of actual crashes. These results form the biomechanical basis for a hypothesis that the facet joint capsule is a source of neck pain and that the pain may arise from large strains in the joint capsule that will cause pain receptors to fire. 展开更多
关键词 whiplash injuries PAIN BIOMECHANICS NECK Zygapophysel joint
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Distribution Characteristics of Meridian Sinew(Jingjin) Syndrome in 313 Cases of Whiplash-Associated Disorders 被引量:1
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作者 陈业孟 赵燕 +8 位作者 薛晓琳 张群策 吴秀艳 李蕙 郑欣 赵振平 何东来 孔军辉 王天芳 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2015年第3期234-240,共7页
Objective:To investigate and analyze the characteristics of Meridian Sinew(Jingjin) syndrome in patients with whiplash-associated disorders(WAD).Methods:From August 2010 to September 2011,313 WAD cases from New ... Objective:To investigate and analyze the characteristics of Meridian Sinew(Jingjin) syndrome in patients with whiplash-associated disorders(WAD).Methods:From August 2010 to September 2011,313 WAD cases from New York and California states were collected.The survey mostly collects the information of "Sinew Knotted Points" and symptoms of four types of Meridian Sinew differentiation—Taiyang,Shaoyin,Shaoyang and Yangming.Results:Among the cases which are on the average of medium injury level,the higher frequency of "Sinew Knotted Points" tenderness were found on Jianwaishu(SI 14),Jianzhongshu(SI 15),Tianchuang(SI 16),C3-6 Spinous Process,Dazhui(GV 14),Fengchi(GB 20),Tianliao(SJ 15) and Tianding(LI 17).The most commonly presented symptoms were widespread spasm and tenderness in the neck(Taiyang),difficulty in lateral flexion(Shaoyang),problems of extension and flexion(Taiyang),and stiffness and pain during neck movement(Yangming).Among the cases,237 cases(75.72%) were related to Taiyang Meridian Sinew syndrome,82 cases(26.20%) to Shaoyin syndrome and 175(55.91%) and176(56.23%) cases to Shaoyang and Yangming syndrome respectively.The most of cases presented in a combination format.The syndrome distribution under Grade Ⅰ,Ⅱ and Ⅲ reflected that more combination of the Meridian Sinew syndromes in the whiplash injury patients which is resulted from more severity of injury.Conclusion:It is practical to identify the location of abnormality through Meridian Sinew differentiation,considering both "Sinew Knotted Points" tenderness and corresponding symptoms,for the local neck symptoms of WAD. 展开更多
关键词 whiplash-association disorders Meridian Sinew(Jingjin)syndrome Sinew Knotted Point
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强震区水电站地面厂房上部结构地震响应分析和抗震措施研究
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作者 刘彪 李志远 +3 位作者 郭胜山 赵建军 赵宗国 董丹丹 《中国水利水电科学研究院学报(中英文)》 北大核心 2025年第4期383-392,共10页
地面厂房上部采用排架柱结构具有节省材料、空间利用高等优点。但由于上下部结构存在显著的质量和刚度突变,地震时将导致上部结构产生强烈的鞭梢效应。因此,厂房排架柱的抗震安全评价及抗震措施研究是排架柱设计的关键问题。其中,排架... 地面厂房上部采用排架柱结构具有节省材料、空间利用高等优点。但由于上下部结构存在显著的质量和刚度突变,地震时将导致上部结构产生强烈的鞭梢效应。因此,厂房排架柱的抗震安全评价及抗震措施研究是排架柱设计的关键问题。其中,排架柱二阶效应的合理模拟是抗震安全评价里的重点和难点,尤其对于国际水电工程设计,如何基于国际规范正确地考虑二阶效应以及降低结构鞭梢效应是目前厂房抗震研究的热点之一。针对上述问题,以印度尼西亚某水电站地面厂房为例开展了厂房上部结构地震响应分析,对比分析了上部结构为排架柱和墙体两种不同设计方案在地震作用下的动力响应特性。研究表明:从基础传来的地震波经厂房下部结构放大后,对上部结构的地震反应影响显著。上部为墙体结构的动力响应小于排架柱结构,增加剪力墙能有效提高厂房的抗震性能。 展开更多
关键词 水电站地面厂房 排架柱结构 鞭梢效应 二阶效应 抗震措施
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某车辆前排座椅鞭打防护性能递进式优化研究
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作者 李仕锋 徐莉 +3 位作者 张新华 涂其川 吴建林 应关 《汽车实用技术》 2025年第23期73-78,共6页
针对某车型前排座椅在《中国新车评价规程(C-NCAP)》2024版鞭打试验中初始性能不达标的问题,该研究基于鞭打损伤机理与“几何-刚度-交互”关键路径分析,提出一套数据驱动的递进式优化方法。通过“几何参数优化-靠背刚度重构-复合结构协... 针对某车型前排座椅在《中国新车评价规程(C-NCAP)》2024版鞭打试验中初始性能不达标的问题,该研究基于鞭打损伤机理与“几何-刚度-交互”关键路径分析,提出一套数据驱动的递进式优化方法。通过“几何参数优化-靠背刚度重构-复合结构协同(引入发泡聚丙烯吸能结构)”三阶段迭代设计,系统调控头后间隙、靠背刚度分布与吸能结构匹配。物理试验结果表明,座椅鞭打性能总分从1.85分提升至4.48分,上颈部弯矩由41.64 Nm降至8.31 Nm,颈部伤害指数(NIC)及其他关键载荷指标均显著改善。研究验证了“机理引导-路径协同-试验验证”系统工程方法的有效性,为汽车座椅鞭打防护性能的优化提供了具有实践参考价值的技术路径。 展开更多
关键词 汽车座椅 鞭打性能 递进式优化 颈部防护 C-NCAP
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高层建筑塔冠钢结构抗震性能影响因素分析
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作者 肖波 《结构工程师》 2025年第1期84-91,共8页
塔冠钢结构与下部主体混凝土结构共同组成了钢-混凝土竖向混合结构,此类结构由于在结合处存在质量、刚度及阻尼比的突变,地震“鞭梢效应”明显,其在地震作用下的整体动力特性、构件的破坏机理目前还缺乏深入的研究。本文采用数值模拟的... 塔冠钢结构与下部主体混凝土结构共同组成了钢-混凝土竖向混合结构,此类结构由于在结合处存在质量、刚度及阻尼比的突变,地震“鞭梢效应”明显,其在地震作用下的整体动力特性、构件的破坏机理目前还缺乏深入的研究。本文采用数值模拟的方法对多遇地震作用下塔冠钢结构的地震响应进行研究,分析了结构阻尼比、塔冠等效质量比以及塔冠与下部结构连接形式等因素对其抗震性能的影响。研究表明:进行整体结构抗震分析时可以采用Rayleigh比例阻尼模拟整个结构的阻尼比;对钢结构塔冠进行抗震分析时,整体模型可采用钢结构的阻尼比;对下部混凝土结构进行抗震分析时,整体模型可采用钢结构和混凝土结构的平均阻尼比。随着塔冠钢结构等效质量比的减小,塔冠钢结构对整个结构地震作用的影响减小。塔冠钢结构与下部混凝土结构在设计时应尽量采用刚接的形式,以最大限度地控制塔冠的变形和连接部位地震剪力。 展开更多
关键词 塔冠钢结构 竖向混合结构 鞭梢效应 抗震分析 阻尼比
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Numerical investigation of the effects of pre-crash braking on occupant neck whiplash injury
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作者 Chengyue Jiang Hao Yang +3 位作者 Xingyu Ming Xin Wang Lihai Ren Hailan Xu 《Transportation Safety and Environment》 2025年第3期22-29,共8页
Among vehicle collisions,rear-end collision is the main injury source of neck whiplash injury.With the increasing prevalence of autonomous emergency braking systems in new vehicles,occupant postures during rear-end co... Among vehicle collisions,rear-end collision is the main injury source of neck whiplash injury.With the increasing prevalence of autonomous emergency braking systems in new vehicles,occupant postures during rear-end collisions have become more diverse.Thus,it is imperative to study the occupant kinematics of out-of-position(OOP)passengers during rear-end collisions.This paper integrated both volunteer tests and computer-aided engineering methods to analyse the occupant kinematics and main whiplash injury indexes for OOP passengers among the braking-induced rear-end collision scenarios.The research results indicated that a larger velocity change of braking resulted in greater occupant head and chest displacements.In rear-end collisions of the same impact severity,the main injury indexes of the OOP occupants were worse when compared with those of the standard seated occupants,among which the lower neck Fz forces were 624%and 411%of the base model,respectively.Furthermore,the relative displacement increased both head and chest peak accelerations.These research results are beneficial for the development of active restraint systems,as well as the update of the whiplash test protocol. 展开更多
关键词 vehicle braking occupant displacement rear-end collision whiplash injury
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岩质边坡爆破振动速度的高程放大效应研究 被引量:107
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作者 陈明 卢文波 +3 位作者 李鹏 刘美山 周创兵 赵根 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2011年第11期2189-2195,共7页
岩质边坡爆破振动的高程放大效应是边坡上振动速度传播规律的重要研究内容之一。基于岩质边坡爆破振动高程响应机制的理论分析以及边坡开挖爆破振动的数值模拟与实例分析,研究边坡爆破振动速度的高程放大效应。结果表明,边坡爆破振动速... 岩质边坡爆破振动的高程放大效应是边坡上振动速度传播规律的重要研究内容之一。基于岩质边坡爆破振动高程响应机制的理论分析以及边坡开挖爆破振动的数值模拟与实例分析,研究边坡爆破振动速度的高程放大效应。结果表明,边坡爆破振动速度的高程放大效应是在一定的条件下产生的,受爆破振动荷载特性及边坡坡形等因素的影响。爆破振动荷载作用下,边坡坡面不同高程台阶岩体结构的自振主频率处于爆破振动荷载主频带范围内,台阶部位岩体结构的振动响应会产生"鞭梢效应",导致台阶部位岩体振动速度放大。在边坡坡形骤变、坡度增大时,边坡上一级台阶岩体的振动速度可大于下一级台阶岩体的振动速度,产生显著的振动速度高程放大效应。坡形相近的条件下,台阶坡脚处的振动速度随高程的增加逐渐减小,不出现振动速度高程放大效应。"鞭梢效应"影响下,边坡台阶边沿的振动速度较大,但应力、应变较同高程台阶坡脚处的小,边沿部位的振动速度不适宜评价边坡的稳定性。 展开更多
关键词 边坡工程 爆破振动 高程 鞭梢效应
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高层结构的鞭梢效应分析 被引量:23
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作者 曲淑英 王心健 +1 位作者 初明进 曲乃泗 《工业建筑》 CSCD 北大核心 2001年第10期28-30,共3页
系统地探讨了结构产生鞭梢效应的原因 ,发现当突出物的基本频率与整体结构的固有频率相同或相近 ,并与地面扰频相接近时 ,最易发生鞭梢效应 ,通过适当调整结构的刚度或质量分布使突出物的频率与整体结构的频率的差值增大 ,可减少鞭梢效... 系统地探讨了结构产生鞭梢效应的原因 ,发现当突出物的基本频率与整体结构的固有频率相同或相近 ,并与地面扰频相接近时 ,最易发生鞭梢效应 ,通过适当调整结构的刚度或质量分布使突出物的频率与整体结构的频率的差值增大 ,可减少鞭梢效应的影响 。 展开更多
关键词 鞭梢效应 固有频率 主体结构 高层结构 结构设计
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筒承式群仓的地震作用分析及试验研究 被引量:14
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作者 王命平 孙芳 +3 位作者 高立堂 荆超 滕锴 耿树江 《工业建筑》 CSCD 北大核心 2005年第10期29-32,8,共5页
通过模型试验及计算机分析,对钢筋混凝土筒承式群仓的自振特性及地震作用进行了研究,分析其变化规律和影响因素。提出了筒承式群仓平动自振基频、结构基本振型指数的计算公式及简化设计方法。
关键词 筒承式 群仓 自振特性 地震作用 鞭梢效应 筒承式群仓 试验研究 计算机分析 简化设计方法 钢筋混凝土
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中国汽车安全技术的现状与展望 被引量:37
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作者 赵福全 吴成明 +2 位作者 潘之杰 刘卫国 刘巍 《汽车安全与节能学报》 CAS 2011年第2期111-121,共11页
面对中国交通事故伤亡率高的现状,企业、学校、研究机构都加大了对汽车安全技术研究开发的投入,加快了安全技术研发能力的提升和产品化进程。自主品牌汽车C-NCAP五星高分的获得标志着中国被动安全技术的飞跃性发展。进一步开展对行人保... 面对中国交通事故伤亡率高的现状,企业、学校、研究机构都加大了对汽车安全技术研究开发的投入,加快了安全技术研发能力的提升和产品化进程。自主品牌汽车C-NCAP五星高分的获得标志着中国被动安全技术的飞跃性发展。进一步开展对行人保护、后排乘员保护、防后碰鞭打保护以及骑自行车人保护等被动安全研究的同时,主动安全系统、预碰撞系统、智能化汽车网络系统的研究开发已经成为关注的热点,更高层次的乘员、车和环境等相关主被动安全技术的统合协调,将推动零碰撞零伤亡汽车安全理念的实现。国家级研究开发及产业化大课题的设立、法规标准的建立和完善将会成为汽车安全技术快速发展的动力。 展开更多
关键词 汽车安全 主动安全系统 行人保护 防后碰鞭打保护 预碰撞安全 智能化交通系统
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