论文部分内容阅读
张文倬-贺行军(水利电力部昆明勘测设计院):钟秉章等同志对埋藏式压力钢管设计提出了新的方法。通过学习,感到该文对今后工作有很大帮助,我们准备将它应用到工程设计中去。现对原文提出几点浅见如下: (一)原文的主要贡献在于使钢管与混凝土和围岩联合受力,并且将钢管应力传递到围岩上去,从而节省钢材。原文提出的按弹塑性设计原理和方法的核心是:充分利用围岩应力。因此,围岩承载能力是主要研究的问题之一。可以设想,如果围岩稳定,在钢管应力产生的变形进入塑性阶段,但还未破坏情况下,钢管应力虽然越过弹性状态而进入塑性状态工作,它是决不会破坏的。因为围岩已经把钢管箍住,从而限制了钢管变形的扩展。这样,就归结为如何保证围岩承载能力的可靠性问题。 (二)原文在推导内水压力作用下的管壁厚度计算公式时,采用的变位相容条件为:
Zhang Wenyu-He Xingjun (Ministry of Water Conservancy and Electric Power Kunming Institute of Survey and Design): Zhong Bingzhang and other comrades proposed a new method for the design of embedded penstocks. Through learning, I feel that the article will be of great help to the future work and we are ready to apply it to engineering design. The following is a brief summary of the original text: (a) The main contribution of the original text lies in the joint force between the steel pipe and the concrete and surrounding rock, and the stress transfer of the steel pipe to the surrounding rock to save steel. The core of the elasto-plastic design principle and method proposed in the original text is: to make full use of the surrounding rock stress. Therefore, the carrying capacity of surrounding rocks is one of the major research issues. It can be assumed that if the surrounding rock is stable, the deformation caused by the stress in the steel pipe enters the plastic stage, but under the condition that it has not been damaged, the stress of the steel pipe will never be destroyed even though it goes through the elastic state and enters the plastic state. Because the surrounding rock has already bound the steel pipe, the expansion of the steel pipe is limited. In this way, it comes down to how to ensure the reliability of the carrying capacity of the surrounding rock. (2) When the original formula for calculating the thickness of the wall under the effect of internal water pressure is deduced, the compatibility conditions used for the displacement are: