EMD265型柴油机摇壁箱划线创新及工艺设计

摇壁箱是EMD265型柴油机的零部件,属于不规则型铸造毛坯件,装夹定位较困难,孔的尺寸精度和位置精度要求较高,加工难度大,加工工艺的设计及划线创新是保证成品质量的关健。摇壁箱先进划线创新操作法的创立,是规范划线实操程序、提高作业效率、缩短工艺周期、满足生产形势的保征。对摇壁箱的加工工艺、装夹方式、工装设计、划线操作法的创新理念进行详解。同时在划线和机械制造领域中首次提出预后理论,并贯穿划线的始终。

3D打印在高分子材料成型加工实验中的探索

3D打印技术融入到高分子材料成型加工实验课程中,是对传统教学模式的改革。并进一步分析了3D打印应用于国内教育。研究表明,在高分子材料成型加工实验课程中引入3D打印可激发学生的创新精神,培养学生的创新能力,同时提高了学生的自我探索知识的能力,培养了符合时代发展的复合型创新性高分子材料与工程的人才,也为高分子材料成型加工实验课的教学改革提供思路和途径。

Proportioning Criteria for Traditional and Innovative Extrados Techniques for the Strengthening of Barrel Vaulted Structures Subjected to Rocking of the Abutments

In this paper, the behavior of barrel-vaulted structures undergoing rocking of the abutments and the effectiveness of a few retrofit solutions are discussed. The comprehension of the structural performance of vault-abutment systems is fundamental for their seismic vulnerability assessment, and for the design of efficient strengthening techniques. In the paper, traditional techniques such as extrados thin concrete slab or masonry spandrel walls as well as an innovative solution with an extrados thin improved lime mortar slab reinforced by means of glass fiber mesh are considered. The different strengthening solutions are studied and compared on the basis of the results of non linear numerical analyses and by reference to a simplified analytical approach. Numerical and analytical models are validated through comparison with the results of a recent experimental study focusing on the behavior of vaulted masonry structures subjected to rocking of the abutments. The validated models can be used by engineers for the seismic vulnerability assessment of masonry vaulted structures as well as for the proportioning of possible extrados strengthening solutions, and will be used in the future to explore different structural system configurations.