## Calculator Description

This online engineering calculator computes the actual bending and shear stresses and allowable bending and shear stresses for a wood glulam member in bending and shear according to the National Design Specification for Wood Construction 2015 (NDS 2015)

https://www.engineeringexamples.net/engineering-calculator-for-analysis-of-wood-glulam-member-in-bending-and-shear-nds-2015/

## Input Parameters

Bending Moment, M

Member Width, b

Member Depth, d

Load Duration Factor, Cd – NDS 2015, Section 5.3.2

Wet Service Condition Factor, Cm – NDS 2015, Section 5.3.3

Temperature Factor, Ct – NDS 2015, Section 5.3.4

Beam Stability Factor, CL – NDS 2015, Section 5.3.5

Volume Factor, Cv – NDS 2015, Section 5.3.6

Flat Use Factor, Cfu – NDS 2015, Section 5.3.7

Curvature Factor, Cc – NDS 2015, Section 5.3.8

Stress Interaction Factor, CI – NDS 2015, Section 5.3.9

Shear Reduction Factor, Cvr – NDS 2015, Section 5.3.10

Reference Bending Stress, Fb – NDS Supplement 2015

Reference Shear Stress Parallel to grain, Fv – NDS Supplement 2015

## Output Parameters

Cross-Sectional Area, A

Section Modulus, S

Actual Bending Stress, fb

Actual Maximum Shear Stress, fv

Allowable Bending Stress, Fb‘ – NDS 2015 Table 5.3.1

Allowable Shear Stress Parallel to Grain, Fv‘ – NDS 2015 Table 5.3.1

Bending Check

Shear Check

## Calculator Description

This online engineering calculator computes the actual bending and shear stresses and allowable bending and shear stresses for a wood sawn lumber member in bending and shear according to the National Design Specification for Wood Construction 2015 (NDS 2015)

https://www.engineeringexamples.net/engineering-calculator-for-analysis-of-wood-sawn-lumber-member-in-bending-and-shear-nds-2015/

## Input Parameters

Bending Moment, M

Member Width, b

Member Depth, d

Load Duration Factor, Cd – NDS 2015, Section 4.3.2

Wet Service Condition Factor, Cm – NDS 2015, Section 4.3.3

Temperature Factor, Ct – NDS 2015, Section 4.3.4

Beam Stability Factor, CL – NDS 2015, Section 4.3.5

Size Factor, CF – NDS 2015, Section 4.3.6

Flat Use Factor, Cfu – NDS 2015, Section 4.3.7

Incising Factor, Ci – NDS 2015, Section 4.3.8

Repetitive Member Factor, Cr – NDS 2015, Section 4.3.9

Reference Bending Stress, Fb – NDS Supplement 2015

Reference Shear Stress Parallel to grain, Fv – NDS Supplement 2015

## Output Parameters

Cross-Sectional Area, A

Section Modulus, Sx

Actual Bending Stress, fb

Actual Maximum Shear Stress, fv

Allowable Bending Stress, Fb‘ – NDS 2015 Table 4.3.1

Allowable Shear Stress Parallel to Grain, Fv‘ – NDS 2015 Table 4.3.1

Bending Check

Shear Check

## Calculator Description

This online engineering calculator computes the actual tensile and bending stresses and allowable tensile and bending stresses for a wood glulam member in tension + bending according to the National Design Specification for Wood Construction 2015 (NDS 2015)

https://www.engineeringexamples.net/engineering-calculator-for-analysis-of-wood-glulam-member-in-tension-plus-bending-per-nds-2015/

## Input Parameters

Tensile Force, P

Bending Moment, M

Member Width, b

Member Depth, d

Net Cross-Sectional Area, An

Load Duration Factor, Cd – NDS 2015, Section 5.3.2

Wet Service Condition Factor, Cm – NDS 2015, Section 5.3.3

Temperature Factor, Ct – NDS 2015, Section 5.3.4

Beam Stability Factor, CL – NDS 2015, Section 5.3.5

Volume Factor, Cv – NDS 2015, Section 5.3.6

Flat Use Factor, Cfu – NDS 2015, Section 5.3.7

Curvature Factor, Cc – NDS 2015, Section 5.3.8

Stress Interaction Factor, CI – NDS 2015, Section 5.3.9

Reference Tension Stress Parallel to Grain, Ft – NDS Supplement 2015

Reference Bending Stress, Fb – NDS Supplement 2015

## Output Parameters

Section Modulus, Sx

Actual Tensile Stress, ft

Actual Bending Stress, fb

Allowable Tension Stress Parallel to Grain, F’– NDS 2015, Table 5.3.1

Allowable Bending Stress without Stability Factor, Fb* – NDS 2015, Section 3.9.1

Allowable Bending Stress withthout Volume Factor, Fb** – NDS 2015, Section 3.9.1

Combined Tension and Bending Check – NDS 2015, Equation 3.9-1

Buckling on the Compression Face Check – NDS 2015, Equation 3.9-2

## Calculator Description

This online engineering calculator computes the actual tensile and bending stresses and allowable tensile and bending stresses for a wood sawn lumber member in tension + bending according to the National Design Specification for Wood Construction 2015 (NDS 2015)

https://www.engineeringexamples.net/engineering-calculator-for-analysis-of-wood-sawn-lumber-member-in-tension-plus-bending-per-nds-2015/

## Input Parameters

Tensile Force, P

Bending Moment, M

Member Width, b

Member Depth, d

Net Cross-Sectional Area, An

Load Duration Factor, Cd – NDS 2015, Section 4.3.2

Wet Service Condition Factor, Cm – NDS 2015, Section 4.3.3

Temperature Factor, Ct – NDS 2015, Section 4.3.4

Beam Stability Factor, CL – NDS 2015, Section 4.3.5

Size Factor, CF – NDS 2015, Section 4.3.6

Flat Use Factor, Cfu – NDS 2015, Section 4.3.7

Incising Factor, Ci – NDS 2015, Section 4.3.8

Repetitive Member Factor, Cr – NDS 2015, Section 4.3.9

Reference Tension Stress Parallel to Grain, Ft – NDS Supplement 2015

Reference Bending Stress, Fb – NDS Supplement 2015

## Output Parameters

Section Modulus, Sx

Actual Tensile Stress, ft

Actual Bending Stress, fb

Allowable Tension Stress Parallel to Grain, F’– NDS 2015, Table 4.3.1

Allowable Bending Stress without Stability Factor, Fb* – NDS 2015, Section 3.9.1

Allowable Bending Stress with Stability Factor, Fb** – NDS 2015, Section 3.9.1

Combined Tension and Bending Check – NDS 2015, Equation 3.9-1

Buckling on the Compression Face Check – NDS 2015, Equation 3.9-2

In this post, I will provide a brief overview of determining thermal factors, Ct, for calculating flat roof snow loads on structures per ASCE 7-10, Table 7-3. The thermal factors are based on the thermal condition of the roof.

## Thermal Factors for Structures Based on Thermal Conditions

Structures kept just above freezing and other with cold, ventilated roofs in which the thermal resistance (R-value) between the ventilated space and the heated space exceeds 25 °F x h x ft2/Btu (4.4 K x m2/W), Ct = 1.1

Unheated and open air structures, Ct = 1.2

Structures intentionally kept below freezing, Ct = 1.3

Continuously heated greenhouses with a roof having a thermal resistance (R-value) less than 2.0 °F x h x ft2/Btu (0.4 K x m2/W), Ct = 0.85

All other structures, Ct = 1.0