双层集装箱平车重车垂向振动加速度值偏大的原因分析

针对双层集装箱平车重车垂向振动加速度值偏大的实际情况，根据线路运行测试结果，从车辆弹性振动的角度分析了加速度值偏大的原因。     

闸瓦间隙自动调整器控制杆弯曲的原因及改进建议

随着我国铁路货车的不断更新，装用ST2-250型闸瓦间隙自动调整器的新型车辆被越来越多地投入运用。     

汽车前轮发摆原因分析及解决办法初探

本文通过对汽车前轮发摆进行多角度分析，找出原因所在。通过一系列措施，解决汽车制动时的安全隐患，提高市场占有率。     

曲轴两端中心孔修正工艺

采用圆角淬火工艺的曲轴在淬火工序完成后,中间挡主轴颈弯曲变形超过0.50 mm的曲轴,磨削时会产生主轴颈磨不出的问题,只能通过增加热定型工序,减少弯曲变形,这样就增加了曲轴的加工成本.为降低曲轴加工成本,设计了一台曲轴修两端中心孔专机.     

乳化橡胶沥青水泥砼疲劳性能及应用研究

论述乳化橡胶沥青水泥砼的弯曲疲劳试验结果及疲劳方程，通过对试件疲劳寿命的修正推导抗弯拉强度结构系数方程，结合试验路工程，对ＥＲＡＣＣ路面及造价进行初步分析。     

螺栓预涂胶的拧松剪切力矩的测量

本文主要对螺栓预涂胶的拧松剪切力矩(Ccd)的测量方法作了介绍，并结合自己的经验对实际工作中经常遇到的问题作了说明。     

The effect of plastic constraint on the initiation of ductile tears in shipbuilding structural steels

In this paper, the effect of plastic constraint on the initiation of ductile tears in four different shipbuilding structural steels has been experimentally studied by measuring the J-integral and crack opening displacement COD at initiation in three-point bend specimens with deep and shallow notches. Experimental results of seven groups of different strength alloy steels show that both Si and Ji values of ductile tear from the shallow crack specimens which have less constraint flow field are significantly higher than those of deeply notched specimens. Slip-line-field analysis shows that, for shallow crack, the hydrostatic stress is lower than that from standard deeply cracked bend specimen, which develops a high level of crack tip constraint, provides a lower bound estimate of toughness, and will ensure an unduly conservative approach when applied to structural defects, especially if initiation values of COD and J-integral are used.