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摘要: 根据三层BP神经网络模型和弹性层状体系理论, 结合JILS FWD研究了层状体系路面的模量反算。通过理论和实测弯沉盆的反算, 比较了精确网络与噪音网络的反算能力, 从而提出了人工神经网络实现模量反算的关键技术。噪音网络与国内外常用反算程序的比较结果表明, 神经网络法的反算结果具有良好的精度和可靠性Abstract: The backcalculation of pavement layer moduli for layered system is researched with JILS FWD according to the model of 3 layered BP neural network and the theory of elastic layered system.The backcalculating ability of accurate network and noise network is compared through the backcalculation of theoretical and measured deflection basins. The key techniques are presented for the backcalculation of moduli with artificial neural networks.The comparisions of the noise network to the common backcalculation programs show that the backcalculation results for the method of neural networks are good in accuracy and reliability.
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表 1 弯沉盆数据
Table 1. Data of deflection basins
数据来源 序号 板厚/cm 荷载/kN 测点位置/cm, 弯沉盆数据/0.01 mm 0 30 40 70 100 130 160 D1 D2 D3 D4 D5 D6 D7 实测数据 1 21 51.20 13.39 12.75 12.40 10.95 9.50 8.10 6.91 2 25 51.73 11.20 10.57 10.39 9.32 8.23 7.09 6.10 3 25 54.18 14.25 13.61 13.36 11.81 10.36 8.74 7.52 理论数据 4 23 48.00 15.30 13.86 13.25 11.34 9.54 7.97 6.66 5 25 50.00 13.73 12.88 12.51 11.29 10.03 8.84 7.75 6 27 52.00 13.39 12.81 12.55 11.69 10.74 9.79 8.87 表 2 精确网络反算模量结果
Table 2. Results of backcalculation of moduli with the accurate BP network
数据来源 序号 面板模量E1/地基模量E0/MPa 精确网络 理论值 实测数据 1 150000/237.4 — 2 150000/4.4 — 3 150000/0.1 — 理论数据 4 30016.6/140.0 30000/140 5 49960.3/120.0 50000/120 6 69965.7/100.0 70000/100 表 3 模量反算结果比较表
Table 3. Comparisons of results for backcalculation of moduli
数据来源 序号 面板模量E1/地基模量E0/MPa, 弯沉平均误差δ/% 噪音网络 EVERCALC MODULUS WESDEF 遗传算法 实测数据 1 67629.2
138.9
(0.90)64661.8
141.2
(0.74)67037.8
140.0
(0.85)67852.3
141.5
(0.80)65522.9
140.9
(0.81)2 59318.7
153.0
(1.27)56786.0
157.5
(0.95)61163.4
154.4
(0.85)59056.6
157.9
(0.90)56602.8
157.4
(0.96)3 42901.3
130.5
(2.00)41511.8
135.3
(1.41)44698.7
132.4
(1.40)43474.8
134.9
(1.40)41432.0
135.1
(1.42)理论数据 4 28921.0
138.3
(1.67)29831.2
140.5
(0.07)29585.4
140.7
(0.10)31254.8
140.5
(0.10)30047.6
139.9
(0.02)5 50691.3
118.2
(0.86)50332.1
119.8
(0.05)50711.0
120.7
(0.05)51331.6
120.3
(0.10)50028.4
120.0
(0.03)6 71550.9
99.4
(0.18)70300.8
99.4
(0.03)70685.1
99.3
(0.08)71307.5
99.7
(0.10)69993.7
100.0
(0.02)注: () 中数据为弯沉平均误差δ (%)。 -
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