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3. RECALIBRATION (Continuation)

Type III INJURY Accidents

The AMFs derived for INJURY accidents for Type III intersections are intersection SKEW angle, commercial driveways on major road, hazard rating on major road, peak truck percentage on major road, and peak turning percentage. The sensitivity test results for these AMFs are presented below.

Table 211. Sensitivity of Safety to Skew Angles for Type III INJURY Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

SKEW Angle (degrees)

A

B

A

B

A

B

A

B

A

B

0

10

15

30

45

400

50

0.002

0.002

0.002

0.002

0.002

0.003

0.003

0.003

0.004

0.003

100

0.002

0.002

0.003

0.003

0.003

0.003

0.004

0.003

0.005

0.004

400

0.003

0.003

0.004

0.004

0.004

0.004

0.005

0.005

0.007

0.005

1,000

100

0.008

0.008

0.009

0.010

0.010

0.010

0.013

0.012

0.016

0.012

500

0.012

0.012

0.014

0.015

0.015

0.016

0.019

0.018

0.025

0.019

1,000

0.014

0.014

0.017

0.018

0.018

0.019

0.023

0.021

0.030

0.023

3,000

100

0.033

0.033

0.039

0.042

0.043

0.044

0.054

0.050

0.069

0.053

500

0.051

0.051

0.060

0.064

0.065

0.068

0.083

0.076

0.106

0.081

1,000

0.061

0.061

0.072

0.076

0.078

0.082

0.100

0.092

0.128

0.098

3,000

0.082

0.082

0.097

0.102

0.105

0.109

0.134

0.123

0.171

0.131

5,000

100

0.066

0.066

0.077

0.082

0.084

0.087

0.107

0.098

0.137

0.105

500

0.101

0.101

0.119

0.126

0.129

0.134

0.164

0.151

0.210

0.161

1,000

0.121

0.121

0.143

0.151

0.155

0.161

0.197

0.181

0.252

0.193

3,000

0.162

0.162

0.191

0.202

0.207

0.215

0.264

0.242

0.337

0.258

5,000

0.185

0.185

0.218

0.231

0.237

0.246

0.302

0.277

0.386

0.296

10,000

100

0.166

0.166

0.195

0.206

0.212

0.220

0.270

0.248

0.345

0.264

500

0.254

0.254

0.299

0.316

0.324

0.337

0.414

0.379

0.528

0.405

1,000

0.305

0.305

0.359

0.380

0.389

0.405

0.497

0.456

0.635

0.486

3,000

0.408

0.408

0.480

0.508

0.521

0.542

0.665

0.610

0.849

0.650

5,000

0.467

0.467

0.549

0.582

0.596

0.620

0.761

0.698

0.972

0.745

10,000

0.561

0.561

0.660

0.699

0.716

0.745

0.915

0.839

1.168

0.895

Note: Group B AADT base model was used

A: AMF derived from full models.

B: AMF derived from regression models.

Table 212. Sensitivity of Safety to Commercial Driveways on Major Road for Type III INJURY Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

Commercial Driveways on Major Road (density)

0

5

10

15

400

50

0.002

0.003

0.004

0.005

100

0.002

0.003

0.004

0.006

400

0.003

0.005

0.006

0.008

1,000

100

0.008

0.011

0.014

0.020

500

0.012

0.016

0.022

0.030

1,000

0.014

0.019

0.027

0.036

3,000

100

0.033

0.046

0.062

0.085

500

0.051

0.070

0.096

0.131

1,000

0.061

0.084

0.115

0.157

3,000

0.082

0.112

0.154

0.210

5,000

100

0.066

0.090

0.123

0.169

500

0.101

0.138

0.189

0.258

1,000

0.121

0.166

0.227

0.310

3,000

0.162

0.222

0.303

0.415

5,000

0.185

0.254

0.347

0.475

10,000

100

0.166

0.227

0.310

0.424

500

0.254

0.347

0.475

0.650

1,000

0.305

0.417

0.571

0.781

3,000

0.408

0.558

0.763

1.044

5,000

0.467

0.639

0.874

1.196

10,000

0.561

0.767

1.050

1.436

Note: Group B AADT base model was used

The AMF for Commercial driveways on major road was derived from full models.

Table 213. Sensitivity of Safety to Hazard Rating on Major Road (HAZRAT1) for Type III INJURY Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

HAZRAT

1

3

5

7

400

50

0.002

0.003

0.005

0.007

100

0.002

0.004

0.006

0.009

400

0.003

0.006

0.008

0.012

1,000

100

0.008

0.014

0.020

0.029

500

0.012

0.021

0.030

0.044

1,000

0.014

0.025

0.037

0.053

3,000

100

0.033

0.059

0.086

0.125

500

0.051

0.090

0.131

0.192

1,000

0.061

0.108

0.158

0.230

3,000

0.082

0.145

0.211

0.308

5,000

100

0.066

0.116

0.169

0.247

500

0.101

0.178

0.259

0.378

1,000

0.121

0.213

0.311

0.454

3,000

0.162

0.286

0.417

0.608

5,000

0.185

0.327

0.477

0.696

10,000

100

0.166

0.292

0.426

0.622

500

0.254

0.447

0.652

0.952

1,000

0.305

0.537

0.784

1.144

3,000

0.408

0.719

1.049

1.530

5,000

0.467

0.823

1.200

1.751

10,000

0.561

0.988

1.442

2.104

Note: Group B AADT base model was used

The AMF for HAZRAT1 was derived from full models.

Table 214. Sensitivity of Safety to Peak Truck Percentage (PKTRUCK) for Type III TOTAL Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

PKTURCK (percent)

0

5

10

15

400

50

0.002

0.002

0.001

0.001

100

0.002

0.002

0.002

0.002

400

0.003

0.003

0.003

0.002

1,000

100

0.008

0.007

0.006

0.005

500

0.012

0.010

0.009

0.008

1,000

0.014

0.013

0.011

0.010

3,000

100

0.033

0.029

0.026

0.023

500

0.051

0.045

0.040

0.035

1,000

0.061

0.054

0.048

0.042

3,000

0.082

0.072

0.064

0.056

5,000

100

0.066

0.058

0.051

0.045

500

0.101

0.089

0.078

0.069

1,000

0.121

0.107

0.094

0.083

3,000

0.162

0.143

0.126

0.111

5,000

0.185

0.163

0.144

0.127

10,000

100

0.166

0.146

0.129

0.113

500

0.254

0.224

0.197

0.174

1,000

0.305

0.269

0.237

0.209

3,000

0.408

0.359

0.317

0.279

5,000

0.467

0.411

0.362

0.319

10,000

0.561

0.494

0.435

0.384

Note: Group B AADT base model was used.

The AMF for PKTRUCK was derived from full models..

Table 215. Sensitivity of Safety to Peak Turning Percentage (PKTURN) for Type III TOTAL Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

PKTURN (percent)

0

10

20

30

400

50

0.002

0.002

0.003

0.004

100

0.002

0.003

0.004

0.005

400

0.003

0.004

0.005

0.007

1,000

100

0.008

0.010

0.013

0.017

500

0.012

0.015

0.020

0.025

1,000

0.014

0.018

0.024

0.030

3,000

100

0.033

0.043

0.055

0.071

500

0.051

0.066

0.085

0.109

1,000

0.061

0.079

0.102

0.131

3,000

0.082

0.106

0.136

0.176

5,000

100

0.066

0.085

0.109

0.141

500

0.101

0.130

0.168

0.216

1,000

0.121

0.156

0.201

0.259

3,000

0.162

0.209

0.269

0.347

5,000

0.185

0.239

0.308

0.397

10,000

100

0.166

0.214

0.275

0.355

500

0.254

0.327

0.422

0.544

1,000

0.305

0.393

0.507

0.653

3,000

0.408

0.526

0.678

0.874

5,000

0.467

0.602

0.776

1.000

10,000

0.561

0.723

0.932

1.202

Note: Group B AADT base model was used.

The AMF for PKTURN was derived from full models.

3.6.4 Type IV Intersections

The predicted TOTAL and INJURY accident frequencies per year for each AMF derived from the full models and regression base models are presented in tables 216 through 224.

Type IV TOTAL Accidents

The AMFs derived for TOTAL accidents for Type IV intersections are intersection SKEW angle, right sight distance from minor road, peak truck percentage, peak through percentage on minor road, and peak left-turn percentage. The sensitivity test results for these AMFs are presented in tables 216 through 220.

Table 216. Sensitivity of Safety to Skew Angles for Type IV TOTAL Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

SKEW Angle (degrees)

0

10

15

30

45

400

50

0.01

0.01

0.01

0.01

0.01

100

0.01

0.01

0.01

0.01

0.01

400

0.02

0.02

0.02

0.02

0.02

1,000

100

0.02

0.03

0.03

0.04

0.04

500

0.06

0.07

0.07

0.08

0.09

1,000

0.08

0.10

0.11

0.12

0.13

3,000

100

0.10

0.13

0.13

0.15

0.16

500

0.23

0.29

0.31

0.35

0.37

1,000

0.32

0.41

0.44

0.49

0.52

3,000

0.57

0.72

0.77

0.87

0.92

5,000

100

0.19

0.24

0.26

0.29

0.31

500

0.44

0.55

0.59

0.66

0.71

1,000

0.62

0.79

0.84

0.95

1.01

3,000

1.09

1.39

1.48

1.67

1.78

5,000

1.42

1.80

1.93

2.17

2.31

10,000

100

0.46

0.59

0.63

0.71

0.75

500

1.06

1.35

1.44

1.62

1.72

1,000

1.51

1.92

2.05

2.31

2.46

3,000

2.66

3.38

3.61

4.06

4.32

5,000

3.46

4.39

4.69

5.27

5.62

10,000

4.93

6.27

6.69

7.53

8.02

Note: Group B AADT base model was used.

The AMF for Intersection SKEW angle was derived from regression base models.


Table 217. Sensitivity of Safety to Right Sight Distance from Minor Road (SDR2) for Type IV TOTAL Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

SDR2

0

500

1,000

1500

400

50

0.005

0.005

0.003

0.002

100

0.007

0.006

0.005

0.003

400

0.015

0.013

0.010

0.006

1,000

100

0.024

0.021

0.015

0.010

500

0.055

0.048

0.035

0.022

1,000

0.079

0.068

0.050

0.032

3,000

100

0.099

0.085

0.063

0.040

500

0.226

0.195

0.144

0.092

1,000

0.323

0.278

0.206

0.131

3,000

0.567

0.488

0.362

0.231

5,000

100

0.191

0.164

0.121

0.077

500

0.435

0.375

0.278

0.177

1,000

0.622

0.535

0.396

0.253

3,000

1.093

0.940

0.697

0.444

5,000

1.420

1.222

0.906

0.577

10,000

100

0.463

0.399

0.296

0.188

500

1.059

0.912

0.675

0.431

1,000

1.512

1.301

0.964

0.615

3,000

2.658

2.288

1.695

1.081

5,000

3.455

2.974

2.203

1.405

10,000

4.932

4.245

3.145

2.005

Note: Group B AADT base model was used.

The AMF for SDR2 was derived from full models.

Table 218. Sensitivity of Safety to Peak Truck Percentage (PKTRUCK) for Type III TOTAL Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

PKTRUCK

0

5

10

15

400

50

0.005

0.004

0.003

0.003

100

0.007

0.006

0.005

0.004

400

0.015

0.012

0.009

0.007

1,000

100

0.024

0.019

0.015

0.012

500

0.055

0.043

0.034

0.027

1,000

0.079

0.062

0.049

0.038

3,000

100

0.099

0.078

0.061

0.048

500

0.226

0.178

0.140

0.110

1,000

0.323

0.254

0.200

0.157

3,000

0.567

0.447

0.351

0.277

5,000

100

0.191

0.150

0.118

0.093

500

0.435

0.343

0.270

0.212

1,000

0.622

0.489

0.385

0.303

3,000

1.093

0.860

0.677

0.533

5,000

1.420

1.118

0.880

0.692

10,000

100

0.463

0.365

0.287

0.226

500

1.059

0.834

0.656

0.516

1,000

1.512

1.190

0.937

0.737

3,000

2.658

2.092

1.646

1.296

5,000

3.455

2.719

2.140

1.684

10,000

4.932

3.882

3.055

2.404

Note: Group B AADT base model was used.

The AMF for PKTRUCK was derived from full models.


Table 219. Sensitivity of Safety to Peak Through Percentage on Minor Road (PKTHRU2) for Type IV TOTAL Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

PKTHRU2

0

10

20

30

400

50

0.005

0.007

0.009

0.011

100

0.007

0.010

0.012

0.016

400

0.015

0.020

0.025

0.032

1,000

100

0.024

0.031

0.040

0.051

500

0.055

0.071

0.091

0.117

1,000

0.079

0.101

0.130

0.166

3,000

100

0.099

0.127

0.163

0.209

500

0.226

0.290

0.372

0.477

1,000

0.323

0.414

0.531

0.681

3,000

0.567

0.728

0.934

1.198

5,000

100

0.191

0.244

0.313

0.402

500

0.435

0.558

0.716

0.919

1,000

0.622

0.797

1.023

1.312

3,000

1.093

1.401

1.798

2.306

5,000

1.420

1.822

2.337

2.998

10,000

100

0.463

0.595

0.763

0.978

500

1.059

1. 359

1.743

2.236

1,000

1.512

1.939

2.488

3.191

3,000

2.658

3.409

4.373

5.610

5,000

3.455

4.432

5.685

7.293

10,000

4.932

6.327

8.116

10.410

Note: Group B AADT base model was used.

The AMF for PKTHRU2 was derived from full models.

Table 220. Sensitivity of Safety to Peak Left-Turn Percentage (PKLEFT) for Type IV TOTAL Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

PKLEFT

0

10

20

30

400

50

0.005

0.007

0.008

0.010

100

0.007

0.009

0.012

0.015

400

0.015

0.019

0.024

0.030

1,000

100

0.024

0.030

0.038

0.048

500

0.055

0.069

0.087

0.110

1,000

0.079

0.099

0.125

0.157

3,000

100

0.099

0.124

0.156

0.197

500

0.226

0.284

0.357

0.449

1,000

0.323

0.406

0.510

0.642

3,000

0.567

0.713

0.897

1.128

5,000

100

0.191

0.240

0.301

0.379

500

0.435

0.547

0.688

0.865

1,000

0.622

0.781

0.983

1.235

3,000

1.093

1.374

1.727

2.172

5,000

1.420

1.786

2.245

2.823

10,000

100

0.463

0.583

0.733

0.921

500

1.059

1.332

1.674

2.105

1,000

1.512

1.901

2.390

3.005

3,000

2.658

3.342

4.202

5.283

5,000

3.455

4.344

5.462

6.868

10,000

4.932

6.202

7.797

9.804

Note: Group B AADT base model was used.

The AMF for PKLEFT was derived from full models.

Type IV INJURY Accidents

The AMFs derived for INJURY accidents for Type IV intersections are intersection SKEW angle, major right-turn lane, peak truck percentage, and peak left-turn percentage. The sensitivity test results for these AMFs are presented in tables 221 through 224.

Table 221. Sensitivity of Safety to Skew Angles for Type IV INJURY Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

SKEW Angle (degrees)

0

10

15

30

45

400

50

0.003

0.004

0.004

0.004

0.005

100

0.004

0.005

0.006

0.006

0.006

400

0.007

0.010

0.010

0.012

0.012

1,000

100

0.012

0.016

0.017

0.019

0.020

500

0.024

0.034

0.036

0.040

0.042

1,000

0.033

0.046

0.050

0.055

0.058

3,000

100

0.046

0.064

0.069

0.077

0.081

500

0.095

0.134

0.143

0.159

0.167

1,000

0.131

0.183

0.196

0.218

0.229

3,000

0.215

0.301

0.323

0.359

0.376

5,000

100

0.087

0.122

0.131

0.145

0.153

500

0.181

0.253

0.271

0.301

0.317

1,000

0.248

0.347

0.372

0.413

0.433

3,000

0.408

0.571

0.611

0.679

0.713

5,000

0.514

0.719

0.771

0.857

0.899

10,000

100

0.208

0.291

0.311

0.346

0.363

500

0.431

0.603

0.646

0.718

0.754

1,000

0.590

0.826

0.884

0.983

1.032

3,000

0.970

1.359

1.456

1.617

1.698

5,000

1.223

1.713

1.835

2.039

2.141

10,000

1.675

2.345

2.513

2.792

2.932

Note: Group B AADT base model was used.

The AMF for Intersection SKEW angle was derived from regression base models.


Table 222. Sensitivity of Safety to Major Right-Turn Lane for Type IV INJURYAccidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

Right-Turn Lane on Major Road

No Right Turn

Right-Turn Lane on One Approach

Right-Turn Lane on Two Approaches

400

50

0.003

0.002

0.002

100

0.004

0.003

0.003

400

0.007

0.006

0.005

1,000

100

0.012

0.010

0.009

500

0.024

0.021

0.018

1,000

0.033

0.028

0.024

3,000

100

0.046

0.040

0.034

500

0.095

0.082

0.071

1,000

0.131

0.112

0.097

3,000

0.215

0.185

0.159

5,000

100

0.087

0.075

0.065

500

0.181

0.156

0.134

1,000

0.248

0.213

0.183

3,000

0.408

0.351

0.302

5,000

0.514

0.442

0.380

10,000

100

0.208

0.178

0.154

500

0.431

0.370

0.319

1,000

0.590

0.507

0.436

3,000

0.970

0.835

0.718

5,000

1.223

1.052

0.905

10,000

1.675

1.441

1.240

Note: Group B AADT base model was used.

The AMF for Major Right-Turn Lane was derived from full models.


Table 223. Sensitivity of Safety to Peak Truck Percentage (PKTRUCK) for Type IV INJURY Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

PKTRUCK

0

5

10

15

400

50

0.003

0.002

0.002

0.001

100

0.004

0.003

0.002

0.002

400

0.007

0.005

0.004

0.003

1,000

100

0.012

0.009

0.007

0.005

500

0.024

0.019

0.014

0.011

1,000

0.033

0.025

0.020

0.015

3,000

100

0.046

0.035

0.027

0.021

500

0.095

0.074

0.057

0.044

1,000

0.131

0.101

0.078

0.060

3,000

0.215

0.166

0.128

0.099

5,000

100

0.087

0.067

0.052

0.040

500

0.181

0.139

0.108

0.083

1,000

0.248

0.191

0.147

0.114

3,000

0.408

0.314

0.242

0.187

5,000

0.514

0.396

0.306

0.236

10,000

100

0.208

0.160

0.123

0.095

500

0.431

0.332

0.256

0.197

1,000

0.590

0.455

0.351

0.270

3,000

0.970

0.748

0.577

0.445

5,000

1.223

0.943

0.727

0.561

10,000

1.675

1.292

0.996

0.768

Note: Group B AADT base model was used.

The AMF for PKTRUCK was derived from full models.


Table 224. Sensitivity of Safety to Peak Left-Turn Percentage (PKLEFT) for Type IV INJURY Accidents Per Year

Major Road AADT (veh/day)

Minor Road AADT (veh/day)

PKLEFT

0

10

20

30

400

50

0.003

0.005

0.008

0.013

100

0.004

0.006

0.011

0.018

400

0.007

0.012

0.020

0.033

1,000

100

0.012

0.020

0.033

0.056

500

0.024

0.041

0.069

0.116

1,000

0.033

0.056

0.094

0.159

3,000

100

0.046

0.078

0.131

0.221

500

0.095

0.161

0.272

0.458