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71.
碳纤维加固钢筋混凝土梁受弯性能非线性有限元分析 总被引:1,自引:0,他引:1
于龙 《水利与建筑工程学报》2010,8(2):113-116
研究混凝土、受拉钢筋和CFRP在开裂、屈服、破坏各阶段的工作状态和受力特点,对认识CFRP加固机理和性能有着重要意义。应用ANSYS建立碳纤维加固钢筋混凝土梁有限元模型,利用单元生死技术模拟CFRP的不同工作状态,对试件梁开裂、屈服、破坏全过程进行非线性有限元分析。分析表明:在钢筋屈服后,CFRP加固钢筋混凝土梁在后期抗弯刚度、延性和极限承载能力方面均有增强;在结构承受较大初始荷载情况下,二次受力问题对加固梁的抗弯刚度、极限承载能力、延性存在一定影响;由于CFRP是在钢筋进入屈服阶段,应力停止增长后才发挥巨大作用,二次受力时的加固也能取得较好效果;分析结果与实测数据吻合。 相似文献
72.
Despite the universal and understandable distress associated with the death of a child from pediatric illness, do psychologists help surviving families in ways that match their need for assistance? Many families do not seek psychological help and cope adaptively with their loss. Indications for psychotherapy with bereaved families are based largely on experience with families who engage in treatment and who have greater distress. Other families may not receive sufficient services but are at risk for ongoing difficulties and unlikely to engage in treatment. Suggestions for intervention are made, with attention to the fit of therapeutic approaches with family needs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
弗洛伊德认为人类存在着死亡本能。死亡本能的目的是结束有机体的生命,使其回归原始的无机状态。试通过对人类死亡之本能这一心理倾向的挖掘,来审视某些文学现象,并进而关注现代人当下的精神生态风貌。 相似文献
74.
Abstract. This study provides new methods of assessing the adequacy of the Poisson autoregressive time-series model for count data. New expressions are given for the score function and the information matrix and these lead to the construction of new types of residuals for this model. However, these residuals often need to be supplemented by formal statistical procedures and an overall test of the model adequacy is given via the information matrix equality that holds for correctly specified models. The techniques are applied to a monthly count data set of claimants for wage loss benefit, in order to estimate the the expected duration of claimants in the system. 相似文献
75.
This study examines the possibility that volunteer support can influence how long terminally ill patients survive. Hospice patient files (N=290) were coded for marital status and volunteer support condition, respectively, the latter on the basis of whether visits from volunteers were requested and received (n=94), requested but not received (n=28), or neither requested nor received (n=168). Baseline health, disease type, and demographic dimensions were comparable across support conditions. Results indicated that when a baseline health status effect was controlled for (p 相似文献
76.
M.M. Mahapatra G.L. Datta B. Pradhan N.R. Mandal 《International Journal of Pressure Vessels and Piping》2006
Achieving adequate top and bottom reinforcement is important to minimize angular distortions in single-pass submerged arc welded (SAW) butt joints. This is achieved in the present work by using a reusable flux-filled backing strip and proper SAW process parameters without resorting to costly distortion mitigation techniques. The butt joints were made without edge (square butts) preparation. The process was also modeled by using three-dimensional finite element analysis by incorporating the top and bottom reinforcements into the modeling. Filler material deposition was also simulated. Temperature distributions and angular distortions obtained from the modeling closely matched with the experimental values. Thus, the cost effective experimental methodology established in the present work can be utilized for minimizing angular distortions in SAW square butts. The modeling methodology adopted can be used for predicting the angular distortions in SAW square butts with top and bottom reinforcements. 相似文献
77.
Comments on the article by K. T. Herbst-Damm and J. A. Kulik (see record 2005-02260-012) entitled Volunteer support, marital status, and the survival times of terminally ill patients. Can a simple and low-cost intervention, such as a visit by a volunteer, extend the life of terminally ill patients? The answer, according to a study by Herbst-Damm and Kulik (2005), is yes. When it comes to quality of life, however, the effects of volunteer visits remain murky. Thus, it is critical that we look beyond effects on longevity and assess how such a program would influence quality of life. Extending the life of terminally ill patients might not always a blessing. Prolonging their life might even cause harm, as it can extend unwanted physical and mental suffering. It may also go against some patients' desire to hasten their death. Despite Herbst-Damm and Kulik's important findings, the current author remains unconvinced as to the merits of implementing volunteer visits as an intervention policy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
I.A. TAUB F.E. Feeherry E.W. Ross K. Kustin C.J. Doona 《Journal of food science》2003,68(8):2530-2537
ABSTRACT: The "quasi-chemical" kinetics model accounts for all 4 phases of the microbial lifecycle based on a proposed series of chemical rate equations. The model fits continuous growth-death kinetics for Staphylococcus aureus in intermediate moisture bread in various conditions of water activity, pH, and temperature. Growth rates evaluated using the quasi-chemical model are compared with values obtained with the Gompertz model. Kinetics data obtained with the quasi-chemical model are integrated with a probabilistic approach to estimate the boundary between growth and no-growth conditions. Continuous modeling of microbial growth/death kinetics in actual foods advances predictive modeling that conventionally separates growth and death models. 相似文献
79.
王薇 《安徽冶金科技职业学院学报》2010,20(3):59-64
Arthur Dimmesdale in The Scarlet Letter and Henry Hurstwood in Sister Carrie have little in common in passion,guilt and death though they follow almost the same pathroad of life.From the comparison between them——their different beliefs,social environments and author's different ideas,we know that the differences under the almost same surface makes literature more colorful which enriches our life. 相似文献
80.
为分析沉积层应变的变化情况,并找出温度与形变的变化规律,采用有限元分析软件ANSYS计算并绘制不同时刻以及不同位置沉积层内的温度及应力应变曲线,在建立传热模型过程中考虑了金属液滴向沉积层的传热以及沉积层向系统外的热量散失等问题.采用在厚度方向以微小层逐层叠加来模拟涂层的增厚,并以此为基础构造沉积层有限元计算模型,应用单元生与死逐层激活层单元参与计算过程.实现移动边界以充分模拟真实的喷涂沉积过程.通过分析不同时刻以及不同位置沉积层内的应力应变曲线,获得了沉积层应力应变变化规律.结果表明,沉积层内存在残余塑性应变,且沉积层与母模接触部位等效应力最大,是最易翘曲的地方,验证了沉积层失稳的一般形式. 相似文献