APPENDIX

A.1. Default Load Case and Combination Factors

Each load is applied to the wall under one of the 26 (A through Z) load cases. The wall is analyzed and designed under load combinations. A load combination is the algebraic sum of each of the load cases multiplied by a load factor.

Load combinations are categorized into service-level and ultimate-level. For each service-level and ultimate-level load combinations, nodal displacement, internal forces in plate and stiffener elements, and reactions are calculated. Additionally, wall cross-sectional forces are calculated for ultimate-level load combinations. The output is available only when solution criteria are met for all load combinations.

For the design of reinforced concrete elements, the required area of steel is calculated due to the element internal forces from the ultimate level combinations. On the other hand, displacement envelopes are determined using the displacement from the service level combinations.

Basic load cases and the corresponding load factors for service and ultimate load combinations are provided as suggested defaults in the input file templates (activated in SETTINGS / STARTUP DEFAULTS) to facilitate user’s input. The default load cases and load combination factors should be modified as necessary at the discretion of the user to meet code provisions and project requirements.

The following default load cases are suggested: A – Dead (D), B – Live (L), C – Snow (S), D – Wind (W), and E – Earthquake (E). Service-level load values are considered for all load cases except case E, in all design codes, and case W, in ACI 318-14 and ACI 318-11 only, which are taken at ultimate level. The suggested default load combination factors for service and ultimate levels are shown below. Under the service load level, allowable stress design load factors are considered per related IBC and NBCC edition. Under the ultimate load level, the load factors are considered per related ACI 318, and CSA A23.3 edition. The user should introduce a new set of service level and ultimate level load combinations for specific project and modeling needs such as checking displacement, drift limits or different applications such as liquid containing tank walls, tilt-up walls, shear walls, retaining walls to name a few. The suggested and subsequently generated load combinations in the Program are just suggestions and they must be thoroughly reviewed by the design professional to ensure their suitability for the specific project at hand and must be updated or modified as required.

For example, in ACI 318-14/11/08/05/02, for service load combinations, the user may choose to utilize the corresponding ASCE 7, Commentary on Appendix C, Serviceability Considerations. The service level load combinations per this criterion are given below for informational purposes only. The design professional shall ensure their suitability for the specific project at hand and these factors must also be updated or modified as required.

For ACI 318-14/11

• Service load combination¹

S1 = 1.0D + 1.0L

S2 = 1.0D + 0.5S

S3 = 1.0D + 0.5L

S4 = 1.0D + 0.5L + 1.0W

S5 = 1.0D + 0.5L - 1.0W

Wind load value, W, above is taken at ultimate level in ASCE 7-10 and applicable to ACI 318-14/11. The service level load factor for W can be calculated as W_a/W, where W_a is the service-level wind load. A factor of 1.0 is provided conservatively as the default load factor since the W_a/W ratio depends on location, occupancy category, exposure, and MRI. The user should modify the factor based on the actual W_a/W ratio. Alternatively, the user may represent service and ultimate wind load levels (W_a and W respectively) by defining them directly under separate load cases and by modifying their corresponding load factors to 0.0 and 1.0 so that the service level wind load is active only in service level combinations and the ultimate level wind load is active only in the ultimate level combinations.

For ACI 318-08

• Service load combination²

S1 = 1.0D + 1.0L

S2 = 1.0D + 0.5S

S3 = 1.0D + 0.5L

S4 = 1.0D + 0.5L + 0.7W

S5 = 1.0D + 0.5L - 0.7W

For ACI 318-05/02

• Service load combination³

S1 = 1.0D + 1.0L

S2 = 1.0D + 0.5S

S3 = 1.0D + 0.5L

S4 = 1.0D + 0.5L + 0.7W

S5 = 1.0D + 0.5L - 0.7W

Any load combination in the Tables below is VALID only if all Principal Loads exist for a given load combination. The Companion Load has no impact in the validity of a given load combination.

A.1.1. For ACI 318-14-11

• Service load combinations:

• Ultimate load combinations:

A.1.2. For ACI 318-08-05

• Service load combinations:

• Ultimate load combinations:

A.1.3. For ACI 318-02

• Service load combinations:

• Ultimate load combinations:

A.1.4. For CSA A23.3-14-04-94

• Service load combinations:

• Ultimate load combinations for CSA A23.3-14:

• Ultimate load combinations for CSA A23.3-04:

• Ultimate load combinations for CSA A23.3-94: