[mimosi]

如题，我用的是SESAM，在风浪流作用下耦合分析计算得到悬链线式系泊锚链的张力，算了3个小时，0.1s的步长，其中有两个点出现了负的张力值，分别是在6000多秒和8000多秒，请问各位，有没有遇到这样的问题，原因一般是什么呢？

[gadfly_lee]

我觉得负张力是可能的，而且不影响统计结果

[bobo]

负值大概多少？一点点应该没问题。关键是看整个3小时的分布是不是成周期状的

[gehen]

If it is chain, not a big problem; if it is wire, something more complex and should be careful.

[gehen]

By the way, how to be the "认证会员" ? Or this is forum of some company or college?

[bobo]

我也想成为“认证会员”，这是个大众论坛吧。

[gadfly_lee]

1，积极发言

2，提出有水平的见地

然后，相信你很快就可以成为认证会员。

[gehen]

are u sure? It seemed to be more students from shanghai jiaotong university and guys of CNOOC. Most questions were quite strange and they were lack of experience apparently. I read very few high level answers as you said, but I can see more "认证会员" . That is why I am conspicious this forum is part of some company.

[shaopizi]

1. 术业有专攻，你认为某些方面 学识和经验不如你的人，在其他方面可能可以做你的老师
2. 此论坛卧虎藏龙，有一些这个行业的老前辈。你多发点有意义的见解，才能调动他们的积极性，这样你就能看到更多high level answers
3. 是否能成为认证会员，水平高不高，跟是否来自交大或者中海油，应该没有直接关系吧？

[gadfly_lee]

引用框（gehen ＠ 2009-12-18）

are u sure? It seemed to be more students from shanghai jiaotong university and guys of CNOOC. Most questions were quite strange and they were lack of experience apparently. I read very few high level answers as you said, but I can see more "认证会员" . That is why I am conspicious this forum is part of some company.

I am sure.
Yes, there are a lot of fresh guys in this forum, but on other hands, there exist very experienced experts for site work, project management, engineering design and even research.
They come from:
1, domestic organizatin such as CNOOC, CSSRC, DISC, STARI, MARIC, COSCO, RAFFLES, HEU, SJTU, TJU, DIT, etc.
2, foreign organization such as TAMU, NUS, NTNU, KEPPEL, etc.

I think you can talk with them and learn useful things from them no matter how "experienced" or "high level" you are.

If you think you are "high level", you can spear more, then you can mobilize more "high level answers".

If you think you are not, then uncessary to say sth like "strange" or "lack of experience".

First, just pay attention to what you have done to this forum before you speak sth.

As to "认证会员", this is not for "high level" guys but do nothing to this forum, but for guys who can attribute sth valuable to this forum, such as more non-meaningless speech, more non-worthless talk, even what he said is not "high level".

[gehen]

baicaibz
“不要埋怨自己当前的工作不是金领，不要埋怨自己当前的工作薪水很低。如果你心中有长远的目标以及相应的规划，相信经过长久的坚持不懈的努力，终究可以成功的。如果只是把眼光放在暂时的物质的收入和享受上，难成大器。 ”
不想对你进行攻击，但拿大的价值观，来判断当前的形式，显然是无稽之谈。所有宣传的正统价值取向，如同你所认为的，这些都是骗这些年轻人的，希望你不要再为虎作伥。你的文字和那些所谓的青年偶像如出一辙，好似在台上作报告宣扬廉洁自律的领导，而真正的情况，下面坐着的年轻人是不清楚的。
20 Jan 2009 - 10:06

That is for you? I agree!

[Striking]

你的悬链线是否可以受压？如果定义受拉的张力为正的话，那么受压的时候则为负值。
有的悬链线是可以受压的。

[gadfly_lee]

引用框（gehen ＠ 2009-12-19）

baicaibz
“不要埋怨自己当前的工作不是金领，不要埋怨自己当前的工作薪水很低。如果你心中有长远的目标以及相应的规划，相信经过长久的坚持不懈的努力，终究可以成功的。如果只是把眼光放在暂时的物质的收入和享受上，难成大器。 ”
不想对你进行攻击，但拿大的价值观，来判断当前的形式，显然是无稽之谈。所有宣传的正统价值取向，如同你所认为的，这些都是骗这些年轻人的，希望你不要再为虎作伥。你的文字和那些所谓的青年偶像如出一辙，好似在台上作报告宣扬廉洁自律的领导，而真正的情况，下面坐着的年轻人是不清楚的。
20 Jan 2009 - 10:06

That is for you? I agree!

呵呵。一笑置之。

[gadfly_lee]

引用框（Striking ＠ 2009-12-20）

你的悬链线是否可以受压？如果定义受拉的张力为正的话，那么受压的时候则为负值。
有的悬链线是可以受压的。

en. Seems resonable.

[mimosi]

引用框（gadfly_lee ＠ 12-05-2009 - 14:02）

我觉得负张力是可能的，而且不影响统计结果

原来有这么解答呢，这里表示感谢。之前一直以为是模型错误，调整了很长的时间，总之谢谢各位。

[Brutallus]

引用框（mimosi ＠ 05-25-2010 - 01:06）

引用框（gadfly_lee ＠ 12-05-2009 - 14:02）

我觉得负张力是可能的，而且不影响统计结果

原来有这么解答呢，这里表示感谢。之前一直以为是模型错误，调整了很长的时间，总之谢谢各位。

可能是运动的幅度太大，导致悬链线拉直，拉直以后是有可能出现负数的，这种case以前碰到过，在浅水里面很容易出现。