7层框架，折减前振动周期(秒)、振型参与质量%第一振型怎么调到50%以下？

1.折减前振动周期(秒)、振型参与质量

振型号 周期(秒) 单个振型参与质量(%) 累加振型参与质量(%)
X平动 Y平动 扭转 X平动 Y平动 扭转
1 1.211094 24.84 0.11 63.37 24.84 0.11 63.37
2 1.013563 8.18 76.38 4.70 33.01 76.49 68.08
3 0.986475 57.61 12.53 20.87 90.63 89.02 88.95
4 0.403199 2.42 0.03 5.67 93.04 89.05 94.61
5 0.330914 0.13 8.28 0.12 93.17 97.34 94.73
6 0.320098 4.39 0.31 1.99 97.57 97.64 96.73
7 0.231240 0.54 0.00 1.44 98.11 97.64 98.17
8 0.188628 0.70 0.18 0.05 98.81 97.82 98.22
9 0.182067 0.07 1.25 0.00 98.88 99.07 98.22
10 0.161264 0.14 0.00 0.22 99.02 99.07 98.44
11 0.152015 0.24 0.01 0.21 99.26 99.08 98.65
12 0.150642 0.01 0.00 0.28 99.27 99.08 98.93
13 0.129858 0.00 0.34 0.00 99.27 99.43 98.93
14 0.122376 0.25 0.01 0.02 99.52 99.44 98.95
15 0.119189 0.03 0.00 0.17 99.56 99.44 99.12
16 0.110481 0.01 0.15 0.00 99.56 99.59 99.12
17 0.099363 0.02 0.00 0.03 99.58 99.59 99.16
18 0.095498 0.10 0.01 0.03 99.68 99.59 99.19
19 0.089336 0.01 0.12 0.00 99.69 99.71 99.19
20 0.079187 0.03 0.00 0.01 99.72 99.71 99.20
21 0.073981 0.00 0.03 0.00 99.72 99.75 99.20
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合计: 99.72 99.75 99.20


应该怎么调、？还有为什么？？求大神