请问用过pile单元的大侠们，在结果输出的时候对于弯矩和剪力一般都有两个，分别是My 、Mz；Fy、 Fz ；
问题（1）对于这两组值，My是由Fz产生的吗？Mz是由Fy产生的吗？我看我输出的结果中Fz为0时，弯矩My是0。
sel-cid node Fx Fy Fz
--------- ------ ----------- ----------- -----------
1 1 -1.160e+003 8.050e+003 0.000e+000
3 -1.160e+003 8.050e+003 0.000e+000
2 3 -1.272e+004 1.213e+004 0.000e+000
4 -1.272e+004 1.213e+004 0.000e+000
3 4 -2.683e+004 8.534e+003 0.000e+000
5 -2.683e+004 8.534e+003 0.000e+000
4 5 -3.213e+004 -3.060e+003 0.000e+000
6 -3.213e+004 -3.060e+003 0.000e+000
5 6 -2.561e+004 -9.568e+003 0.000e+000
7 -2.561e+004 -9.568e+003 0.000e+000
6 7 -2.104e+004 -7.072e+003 0.000e+000
8 -2.104e+004 -7.072e+003 0.000e+000
7 8 -1.622e+004 -4.509e+003 0.000e+000
9 -1.622e+004 -4.509e+003 0.000e+000
8 9 -1.210e+004 -2.635e+003 0.000e+000
10 -1.210e+004 -2.635e+003 0.000e+000
9 10 -8.240e+003 -1.292e+003 0.000e+000
11 -8.240e+003 -1.292e+003 0.000e+000
10 11 -4.067e+003 -3.965e+002 0.000e+000
12 -4.067e+003 -3.965e+002 0.000e+000
11 12 -1.707e+003 -1.012e+002 0.000e+000
2 -1.707e+003 -1.012e+002 0.000e+000
Flac3D>print sel pile moment
Moment vector acting at ends of each SEL. . .
(expressed in SEL local system)
sel-cid node Mx My Mz
--------- ------ ----------- ----------- -----------
1 1 0.000e+000 0.000e+000 -4.833e+000
3 0.000e+000 0.000e+000 -8.055e+003
2 3 0.000e+000 0.000e+000 -8.060e+003
4 0.000e+000 0.000e+000 -2.019e+004
3 4 0.000e+000 0.000e+000 -2.018e+004
5 0.000e+000 0.000e+000 -2.872e+004
4 5 0.000e+000 0.000e+000 -2.872e+004
6 0.000e+000 0.000e+000 -2.566e+004
5 6 0.000e+000 0.000e+000 -2.565e+004
7 0.000e+000 0.000e+000 -1.608e+004
6 7 0.000e+000 0.000e+000 -1.607e+004
8 0.000e+000 0.000e+000 -9.000e+003
7 8 0.000e+000 0.000e+000 -9.015e+003
9 0.000e+000 0.000e+000 -4.506e+003
8 9 0.000e+000 0.000e+000 -4.485e+003
10 0.000e+000 0.000e+000 -1.850e+003
9 10 0.000e+000 0.000e+000 -1.833e+003
11 0.000e+000 0.000e+000 -5.404e+002
10 11 0.000e+000 0.000e+000 -5.100e+002
12 0.000e+000 0.000e+000 -1.135e+002
11 12 0.000e+000 0.000e+000 -1.004e+002
2 0.000e+000 0.000e+000 8.291e-001
（2）为什么剪力有时候只有一个方向有值，另外一个方向是0；有时候又两个方向都有？明明是一样的加桩方法啊。
