基于连续损伤力学的复合材料单剪螺栓连接强度估算策略

针对中国缺少T800级复合材料螺栓连接设计参数的问题，发展一种综合连续损伤力学（CDM）和工程算法的单剪连接强度估算策略，以替代试验，降低研究周期和成本。在该强度估算策略中，首先建立试件的CDM有限元模型，通过数值模拟得到单剪螺栓连接的设计参数，包括单剪挤压强度修正系数、无缺口层合板拉伸强度和应力集中减缓因子等。随后根据上述参数，建立工程算法，估算复合材料单剪螺栓连接的最终挤压强度。结果表明:通过该策略得到的T800级复合材料螺栓连接设计参数和强度估算结果与试验结果有较好的一致性，说明该强度估算策略的可行性。 

A continuum damage mechanics-based strength prediction strategy for single-lap,composite bolted joint

Considering the fact that the design parameters for bolted joint in T800 grade composites are extremely scarce in China, a joint strength prediction strategy substituting the tests was developed to save research time period and cost. This proposed strategy is a combination of the continuum damage mechanics (CDM) and engineering approach. First, in this strength prediction strategy, CDM finite element model for the test specimen was utilized to determine the design parameters for bolted joint structure, such as modified bearing strength parameter for single-lap, composite bolted joint, un-notched laminate tensile strength and stress concentration relief factor. Then, based on these design parameters, an efficient engineering algorithm was established to obtain the ultimate bearing strength of single-lap, composite bolted joints. It can be found that the design parameters and strength estimation results for bolted joint in T800 grade composites based on this strategy show excellent agreement with the test results. This demonstrates the strategy is feasible.