ys=yield_strength, r=r, kclosure=kclosure,
threshold=threshold)
# Kmax at Overload计算
k_max_ol = mts_analysis.DeltaKCalculating(b=thickness,
w=width,
a=aol_hold,
pmax=pol,
pmin=0)
# 塑性区系数及尺寸计算
factor = overload_analysis.FactorXiaoping(kmax=k_max_ol,
t=thickness,
ys=yield_strength)
r_ol = overload_analysis.PlasticZoneWithFactor(kmax=[k_max_ol],
ys=yield_strength,
factor=factor)
# 计算dK_eff
dkeff = []
dk_willenborg = []
for seq, value in enumerate(a_Manual):
# 只计算裂纹长度扩展到aol_hold以后的数据的dk_eff(未施加高载以前的不进行计算)
if value > aol_minrate:
k_red = k_max_ol * np.sqrt(1 - (a_Manual[seq] - aol_minrate) * 1e-3 /
r_ol) - dk_Manual[seq] / (1 - r)
kmax_eff = dk_Manual[seq] / (1 - r) - k_red
if dk_Manual[seq] * r / (1 - r) > k_red:
kmin_eff = dk_Manual[seq] * r / (1 - r) - k_red
else:
kmin_eff = 0
read_data.ReadTestInf(sequence=sequence[0])
cycles, cracklength, kmax, kmin, pmax, pmin = read_data.ReadOriginResult(
sequence[0], closure=False, cod=False)
dadn_Manual, n_Manual, dk_Manual, a_Manual = \
experiment_calculation.FCGRandDKbyOriginalData(b=thickness, w=width, n=cycles, pmax=pmax, pmin=pmin,
a=cracklength,
ys=yield_strength, r=stress_ratio, threshold=threshold)
# 实验数据读取和初步处理
kol = mts_analysis.DeltaKCalculating(b=thickness,
w=width,
a=aol,
pmax=pol,
pmin=0)
rol = overload_analysis.PlasticZoneWithFactor(kmax=np.array([kol]),
ys=yield_strength,
factor=factor)
# 高载参数计算
dadn_ola, dk_ola, n_ola, a_ola = \
mts_analysis.FCGDataSelectByThreshold(dadn=dadn_Manual, dk=dk_Manual, n=n_Manual, a=a_Manual,
threshold=aol, target='a', keepbigger=1)
# 以高载时裂纹长度aol筛选出高载后的数据
kmax_ola = np.array([dk / (1 - stress_ratio) for dk in dk_ola])
rm_ola = overload_analysis.PlasticZoneWithFactor(kmax=kmax_ola,
ys=yield_strength,
factor=factor)
# 高载段参数计算
m1, _ = overload_analysis.WheelerFittingBaseParis(a=a_ola,
specimen.a_dadn_min = 13.8055
specimen.a_kc_max = specimen.a_alpha_end
specimen.a_alpha_end += 2.5
specimen.specimen_print()
# paris参数
c_ca, m_ca = paris_and_walker.ParisParameter(r=specimen.stress_ratio)
# Overload PLZ相关参数，塑性区系数为Irwin
kol = mts_analysis.DeltaKCalculating(b=specimen.thickness,
w=specimen.width,
a=specimen.a_ol_applied,
pmax=specimen.overload,
pmin=0)
plz_ol = overload_analysis.PlasticZoneWithFactor(kmax=np.array([kol]),
ys=specimen.yield_stress,
factor=plz_factor,
t=specimen.thickness)
# 数据筛选（筛选出dadn_min后的数据，标记为1）
dadn_1, dk_1, kc_1, n_1, a_1 = specimen.data_select_by_cracklength(
lowerlimit=specimen.a_dadn_min, upperlimit=specimen.a_kc_max)
# 移动平均
if moving_average:
print('Notice: moving average working!')
dadn_ave, dk_ave = closureanalysis.DoubleDataSelectMovingAverage(
data=specimen.dadn, reference=specimen.dk, ratio=0.2, numofaverage=7)
_, a_ave = closureanalysis.DoubleDataSelectMovingAverage(
data=specimen.dadn, reference=specimen.a, ratio=0.2, numofaverage=7)
dadn_temp, dk_temp = closureanalysis.DoubleDataSelectMovingAverage(
data=dadn_1, reference=dk_1, ratio=0.2, numofaverage=7)
_, a_temp = closureanalysis.DoubleDataSelectMovingAverage(data=dadn_1,
read_data.ReadTestInf(sequence=sequence[0])
cycles, cracklength, kmax, kmin, pmax, pmin = read_data.ReadOriginResult(
sequence[0], closure=False, cod=False)
dadn_Manual, n_Manual, dk_Manual, a_Manual = \
experiment_calculation.FCGRandDKbyOriginalData(b=thickness, w=width, n=cycles, pmax=pmax, pmin=pmin,
a=cracklength,
ys=yield_strength, r=stress_ratio, threshold=threshold)
# 高载参数计算
kol = mts_analysis.DeltaKCalculating(b=thickness,
w=width,
a=a_ol,
pmax=pol,
pmin=0)
rol = overload_analysis.PlasticZoneWithFactor(kmax=np.array([kol]),
ys=yield_strength,
factor=1 / math.pi)
# 以高载时裂纹长度aol筛选出高载后的数据
dadn_ola, dk_ola, n_ola, a_ola = \
mts_analysis.FCGDataSelectByThreshold(dadn=dadn_Manual, dk=dk_Manual, n=n_Manual, a=a_Manual,
threshold=a_fcgr_min, target='a', keepbigger=1)
# 高载段参数计算
kmax_ola = np.array([dk / (1 - stress_ratio) for dk in dk_ola])
rm_ola = overload_analysis.PlasticZoneWithFactor(kmax=kmax_ola,
ys=yield_strength,
factor=1 / math.pi)
# Wheeler模型指数系数m1拟合
m1, _ = overload_analysis.WheelerFittingBaseParis(a=a_ola,
# 计算塑性区大小
# 2018/10/15 Version 1.0
# Lu Yunchao
from FCGAnalysisLib import overload_analysis
from FCGAnalysisLib import mts_analysis
from FCGAnalysisLib import paris_and_walker
import numpy as np
sequence = ["yang-baoban_Lu-420-05"]
specimen_data = paris_and_walker.test_database2(specimen=sequence[0])
ys = 0.365 # GPa
a_ol = np.array([specimen_data["a_ol_applied"]]) # mm
p_ol = specimen_data["overload"] # N
p_max = specimen_data["maxload"]
a_kc_max = specimen_data["a_kc_max"]
print('specimen:'+sequence[0]+',a_ol_applied:'+str(a_ol)+'mm,overload:'+str(p_ol)+'N, maxload:'+str(p_max))
b = 2.5 # mm
w = 40 # mm
k_ol = np.array([mts_analysis.DeltaKCalculating(b=b, w=w, a=a_ol, pmax=p_ol, pmin=0)])
k_kc_max = np.array([mts_analysis.DeltaKCalculating(b=b, w=w, a=a_kc_max, pmax=p_max, pmin=0)])
factor = overload_analysis.FactorXiaoping(kmax=k_ol, t=b, ys=ys)
print(factor)
print(str(1/np.pi))
r_ol = overload_analysis.PlasticZoneWithFactor(kmax=k_ol, ys=ys, factor='Xiaoping', t=b)
r_kc_max = overload_analysis.PlasticZoneWithFactor(kmax=k_kc_max, ys=ys, factor='Xiaoping', t=b)
print("r_ol:", r_ol)
print("r_kc_max:", r_kc_max)
def BiSelection(a,
b,
const,
t,
w,
ys,
a_ol_applied,
pmax,
plz_factor,
accu=0.001):
# 利用二分法计算主导位置变化
# 裂纹自高载后的扩展长度+循环塑性区尺寸是已知值，但循环区尺寸是扩展长度的函数且不易解，故采用二分法求解
# 求解的方程可表示为求解长度da使方程：
# da + plz,reversing(da) - plz,ol * precentage(44% for OLR = 2, 80% for OLR = 1.5）= 0
# input arguments:
# a, b: 二分法的左右两端
# const：高载塑性区尺寸乘比例（44% or 80%）
# t, w, ys: 试件的thickness、width和yielding stress，可由类读取
# a_ol_applied：试验高载时对应裂纹长度，可由类读取
# pmax：试验中循环载荷峰值，可由类读取
# plz_factor：塑性区尺寸，可输入常数或Xiaoping，若输入Xiaoping则会自动根据试件尺寸计算
# accu：二分法精度，默认为0.001
# return arguments:
# result: 数组，第0位为解的值x，第1位为此时函数的值
i = 0 # 计数器
# 计算二分法左端的函数值
ka = mts_analysis.DeltaKCalculating(b=t,
w=w,
a=a_ol_applied + a,
pmax=pmax,
pmin=0)
plza = overload_analysis.PlasticZoneWithFactor(kmax=[ka],
factor=plz_factor,
ys=ys,
t=t)
ya = a + plza - const
# 计算二分法右端的函数值
kb = mts_analysis.DeltaKCalculating(b=t,
w=w,
a=a_ol_applied + b,
pmax=pmax,
pmin=0)
plzb = overload_analysis.PlasticZoneWithFactor(kmax=[kb],
factor=plz_factor,
ys=ys,
t=t)
yb = b + plzb - const
result = []
# 若两端为0的情况：
if ya == 0:
result.append(a)
result.append(ya)
elif yb == 0:
result.append(b)
result.append(yb)
else:
# 若两端不为零->进入二分法
while i >= 0:
c = (a + b) / 2
# 计算中点的函数值
kc = mts_analysis.DeltaKCalculating(b=t,
w=w,
a=a_ol_applied + c,
pmax=pmax,
pmin=0)
plzc = overload_analysis.PlasticZoneWithFactor(kmax=[kc],
factor=plz_factor,
ys=ys,
t=t)
yc = c + plzc - const
# 判断解的范围精度是否满足accu的设定
if np.abs(b - a) < accu:
result.append(c)
result.append(yc)
print('Find Zero_point due to tolrance at c=' + str(c))
break
if yc == 0:
result.append(c)
result.append(yc)
print('Find Zero_point due to Midpoint_value=0 at c=' + str(c))
break
elif yc * ya < 0:
b = c
i = i + 1
continue
elif yc * yb < 0:
i = i + 1
a = c
continue
else:
print(
'ERROR: Unexpected situation come across.Check the process.'
)
break
return result