Wind loading is one of the most important loads for controlling the design of large-span roof structures. Equivalent static wind loads, which can generally aim at determining a specific response, are widely used by st...Wind loading is one of the most important loads for controlling the design of large-span roof structures. Equivalent static wind loads, which can generally aim at determining a specific response, are widely used by structural designers. A method for equivalent static wind loads applicable to multi-responses is proposed in this paper. A modified load- response-correlation （LRC） method corresponding to a particular peak response is presented, and the similarity algorithm implemented for the group response is described. The main idea of the algorithm is that two responses can be put into one group if the value of one response is close to that of the other response, when the structure is subjected to equivalent static wind loads aiming at the other response. Based on the modified LRC, the grouping response method is put forward to construct equivalent static wind loading. This technique can simultaneously reproduce peak responses for some grouped responses. To verify its computational accuracy, the method is applied to an actual large-span roof structure. Calculation results show that when the similarity of responses in the same group is high, equivalent static wind loads with high accuracy and reasonable magnitude of equivalent static wind distribution can be achieved.展开更多
在高内压循环作用下地下储气库衬砌易产生裂缝与渗透通道,密封层受力与裂缝控制问题尤为关键。基于有限-离散元方法(finite-discrete element method,简称FDEM),建立了连续-非连续的围岩-衬砌-密封层整体模型,系统研究了平钢板与波拱两...在高内压循环作用下地下储气库衬砌易产生裂缝与渗透通道,密封层受力与裂缝控制问题尤为关键。基于有限-离散元方法(finite-discrete element method,简称FDEM),建立了连续-非连续的围岩-衬砌-密封层整体模型,系统研究了平钢板与波拱两类钢衬及预设缝设计参数对衬砌裂缝演化与密封性能的影响。结果表明,平钢板型密封层应力水平和裂缝数量较高,整体性差,预设缝改善衬砌开裂与密封结构受力作用有限;波拱型结构能显著降低峰值应力并改变裂缝分布,使得裂缝多集中在波拱底部,整体裂缝数量减少,但波拱处的裂缝开裂宽度更大。采用波拱+预设缝相结合的方案可进一步均匀化开裂,减少密封钢衬应力。随着波拱和预设缝数量增加,应力分布趋于均匀,裂缝扩展受控,但最大裂缝宽度呈先减后增趋势,钢衬应力模式由拉应力向弯-剪应力转变。当缝设于拱底时,裂缝可沿预设路径均匀扩展,并可结合防排水措施降低渗透风险。总体而言,波拱+预设缝复合设计在引导裂缝、释放应变和提升密封渗透性能方面具有显著优势,为储气库密封-衬砌协同优化设计提供参考。展开更多
基金Ministry of Science and Technology of China Under Grant No.SLDRCE10-B-04the National Natural Science Foundation Under Grant No.50621062
文摘Wind loading is one of the most important loads for controlling the design of large-span roof structures. Equivalent static wind loads, which can generally aim at determining a specific response, are widely used by structural designers. A method for equivalent static wind loads applicable to multi-responses is proposed in this paper. A modified load- response-correlation （LRC） method corresponding to a particular peak response is presented, and the similarity algorithm implemented for the group response is described. The main idea of the algorithm is that two responses can be put into one group if the value of one response is close to that of the other response, when the structure is subjected to equivalent static wind loads aiming at the other response. Based on the modified LRC, the grouping response method is put forward to construct equivalent static wind loading. This technique can simultaneously reproduce peak responses for some grouped responses. To verify its computational accuracy, the method is applied to an actual large-span roof structure. Calculation results show that when the similarity of responses in the same group is high, equivalent static wind loads with high accuracy and reasonable magnitude of equivalent static wind distribution can be achieved.
文摘在高内压循环作用下地下储气库衬砌易产生裂缝与渗透通道,密封层受力与裂缝控制问题尤为关键。基于有限-离散元方法(finite-discrete element method,简称FDEM),建立了连续-非连续的围岩-衬砌-密封层整体模型,系统研究了平钢板与波拱两类钢衬及预设缝设计参数对衬砌裂缝演化与密封性能的影响。结果表明,平钢板型密封层应力水平和裂缝数量较高,整体性差,预设缝改善衬砌开裂与密封结构受力作用有限;波拱型结构能显著降低峰值应力并改变裂缝分布,使得裂缝多集中在波拱底部,整体裂缝数量减少,但波拱处的裂缝开裂宽度更大。采用波拱+预设缝相结合的方案可进一步均匀化开裂,减少密封钢衬应力。随着波拱和预设缝数量增加,应力分布趋于均匀,裂缝扩展受控,但最大裂缝宽度呈先减后增趋势,钢衬应力模式由拉应力向弯-剪应力转变。当缝设于拱底时,裂缝可沿预设路径均匀扩展,并可结合防排水措施降低渗透风险。总体而言,波拱+预设缝复合设计在引导裂缝、释放应变和提升密封渗透性能方面具有显著优势,为储气库密封-衬砌协同优化设计提供参考。
