【作者】 刘小映；

【导师】 邹银生；

【作者基本信息】 湖南大学 ， 结构工程， 2006， 硕士

【摘要】 在各种自然灾害中,地震灾害是造成人员伤亡和经济损失最严重的灾害之一。结构的抗震设计对防灾减灾具有重要意义,抗震措施是抗震设计的重要内容之一,它包括内力调整和抗震构造措施。本文在参阅国内外抗震措施的试验及理论研究的基础上,通过与新西兰、欧共体、美国等抗震规范条文对比,对我国混凝土结构抗震措施的合理性进行了分析。本文分析了底层柱底抗弯能力增强措施对钢筋混凝土框架抗震性能的影响,并介绍了国内对我国抗震混凝土结构强度级差措施有效性所做的识别工作以及所做的各种与轴压比相关因素的对比试验。为了保证在大震作用下框架结构的稳定性,借鉴国外规范“柱-梁承载力级差系数”的思想,本文提出了对部分抗震等级的框架结构的柱端抗弯能力增强系数应予以提高,以降低框架柱屈服的可能性;参照国外有关规范的发展,本文建议对于正、负剪力反向且比值较大的框架梁宜增加交叉斜筋,以防止沿垂直裂缝发生严重的剪切错动。本文分析表明,在高烈度地区按我国规范设计的框架结构延性偏小,主要原因是潜在塑性铰区长度偏小,建议对二、三级抗震等级的框架结构,其箍筋加密区的长度应适当增加;对9度区的框架结构在离开柱边一定距离的潜在正弯矩塑性铰区应增加相应的抗震构造措施;我国混凝土结构对一级抗震等级框架梁、柱的最小配筋率的规定是合理的,但对二、三、四级抗震等级的要求明显偏低,本文提出应提高二、三、四级抗震等级框架梁、柱的最小配筋率的建议;限制框架柱的轴压比对提高框架结构的延性具有重要意义,可以通过提高配箍率、采用连续复合螺旋箍等措施来适度放宽框架柱轴压比的限值。更多还原

【Abstract】 Earthquake disaster is one of the most serious disasters, which may result in heavy casualties and economic losses. Seismic design is important Based on experimentations and analysis about seismic fortification measures in domestic and overseas, and by comparing seismic design provisions with seismic codes in New Zealand, European Community, the United States, it is analyzed the rationality of seismic fortification measures of concrete structure in China.To guarantee the stability of the frame in strong earthquake motion, and on the basis of analysis on the concept of“Capacity Design”in the above three countries seismic design provisions, it is advised that the moment amplification coefficients at the bottom sections of columns for the frame structures in some seismic intensity be increased to reduce the possibility of the frame column yielding. Taking the above three countries seismic codes as reference, it is recommended that it be added details of seismic design by using diagonal shear reinforcement to safeguard beams against sliding shear failure, When the Positive-Negative shear forces are reverse and the ratio is high. The ductility of the frame structures in high intensity regions in China is low. The main reason is that the length of potential plastic hinge regions in beams is short. It is advised that the length of potential plastic hinge regions for seismic grade 2 and 3 be increased. And it is recommend that it be added some details of seismic design in potential positive plastic regions for frame structures in intensity 9. The minimum reinforcement ratios of the frame beam and column of seismic grade 1 given in Chinese code is reasonable. But those of seismic grade 2, 3, 4 are low. It is recommended that those of seismic grade 2, 3 and 4 be enhanced. It is important for good ductility for concrete structures by restricting the axial compression ratios of columns, which may be increased by increased the ratios of hoops and by using continuous compound spiral reinforcement columns.更多还原