Development of expert-friendly system for the evaluation of damage and strength of structures

1. 为了使专家友好型系统更有效，我们开发了一种新的算法。专家系统通常由几个独立的程序模块组成，为了便于进行交互分析，必须将它们连接起来。在MS-DOS系统中使用子进程解决了这些问题。最后，我们可以将疲劳强度估计系统、热冲击问题估计系统和可靠性分析估计系统结合起来。管道不稳定韧性断裂评价专家系统的开发利用常规弹塑性断裂很难理解评价结果的物理意义。在本研究中，利用载荷-位移曲线结合缺陷尺寸、J积分值，建立了评价韧性断裂稳定状态极限的体系。最后，将热应力评价系统与热冲击评价系统相结合，对热冲击现象有了更好的认识。疲劳强度评估专家系统的开发首先，将日本材料科学学会提供的在日本广泛应用的疲劳数据安装在外围数据库系统DBASE III上。接下来，通过使用原则1。，将用FORTRAN语言编写的主程序与数据库系统相结合，完成了专家友好的疲劳强度评价系统。在可靠性分析专家系统的基础上，增加可靠性分析系统，完成了对专家友好型系统的开发。该系统从数据库系统中提取出载荷和疲劳强度的统计数据，便于进行可靠性分析。相反，可以确定荷载和强度数据的散点容忍边界，以满足任意可靠度水平。

1. Development of a new algorithm for the expert-friendly systemTo make a expert-friendly effectively, we have developed a new algorithm. Normally, expert system consists of several independent program modules and they must be linked easily for the interctive analysis. Using a child process in MS-DOS system, we have solved those problems. Finally we can combine a estimation system for fatigue strength, one for thermal shock problems and one for reliability analysis.2. Development of a expert system of the evaluation for the unstable ductile fracture of pipesIt is hard to understand the physical meaning of the result by using the normal elastic-plastic fracture. In the present research, the system to evaluate the limitation of stable condition in ductile fracture has been developed by using the load-displacement curve together with the flaw size, J integral values. Finally, evaluation system for thermal stresses is combined to those system and we get to understand the thermal shock phenomena well.3. Development of a expert system for the evaluation of the fatigue strengthFirst, the fatigue data, which is provided from the Society of Materials Science, Japan and is widely prevailed in Japan, was installed on the peripheral database system DBASE III. Next, by using the principle 1., a main program written in FORTRAN language is combined to the database system and the expert-friendly evaluation system for the fatigue strength evaluation can be completed.4. Development of a expert system for the reliability analysisTotal expert-friendly system was completed by adding the reliability analysis system to the above system. By the system, the reliability analysis can be executed easily by giving the statistical prosperity of the load and the fatigue strength data which is extracted from the database system. On the contrary, the tolerable boundary of the scatter of both the load and the strength data can be decided so as to satisfy the arbitrary reliability level.