Definitions of predefined parameters which can be used in a constraints file in order to create or modify design rules are listened in the following.


The parameter’s input is not case sensitive.

Material properties

F_CD Design compressive strength of concrete [MPa]
F_CK Nominal strength of concrete [MPa]
F_CM Mean value of compressive strength of concrete [MPa]
F_CTD Design tensile strength of concrete [MPa]
F_CTM Mean value of tensile strength of concrete [MPa]
F_BD Bond strength of concrete [MPa] (DIN EN1992-1-1, 8.4.2)
F_YK Characteristic yield strength of reinforcement [MPa]
F_YD Design yield strength of reinforcement [MPa]
F_TK Characteristic tensile strength of reinforcement [MPa]

Section & layer geometry

SECTION_HEIGHT Height of section [m]
SECTION_WIDTH Width of section [m]
LAYER_ID Number of layer
LAYER_ZS Local z-coordinate of layer [m]
LAYER_WIDTH Length of layer [m]
IS_COLUMN Boolean variable: 1=true, 0=false
IS_BEAM Boolean variable: 1=true, 0=false
ISLOWERREINFORCEMENT Boolean variable: 1=true, 0=false
ISUPPERREINFORCEMENT Boolean variable: 1=true, 0=false
ISBASEREINFORCEMENT Boolean variable: 1=true, 0=false
MAXBARSTEPDIFFERENCE Maximum step difference between base and supplemental reinforcement diameter

Longitudinal reinforcement

ISMAINDIRECTION Condition for reinforcement in main direction (Boolean variable: 1=true, 0=false)
C_ASL Cover of longitudinal reinforcement [m]
D_ASL Diameter of longitudinal reinforcement used [m]
D_KST Diameter of constructive reinforcement [m]
D_ASL Diameter of base longitudinal reinforcement [m]
D_ASL2 Diameter of supplemental longitudinal reinforcement [m]
S_ASL Spacing of longitudinal reinforcement [m]
S_ASL2 Spacing of longitudinal reinforcement [m]
ASL_REQ_MAX Required maximal longitudinal reinforcement [m2]
ASL_PRO Longitudinal reinforcement provided [m2]
N_ASL Number of longitudinal bars
ASL_UTIL Utilization factor as_req/as_pro
F_ASL Factor for over-/under-reinforcement

Shear / transverse reinforcement

ISTRANSDIRECTION Condition for reinforcement in transverse direction (Boolean variable: 1=true, 0=false)
C_ST Cover of shear reinforcement [m]
D_ST Diameter of shear reinforcement [m]
S_ST Spacing of shear reinforcement [m]
ASB_REQ_MAX Required shear reinforcement [m2/m]
ASB_PRO Minimum shear reinforcement [m2/m]
HOOK_ANGLE Angle of the hook
HOOK_LENGTH Length of the hook
F_ASB Factor for over-/under-reinforcement

Anchorage of reinforcement

IS_ANCHORAGE_STRAIGHT Boolean variable: 1=true, 0=false
IS_ANCHORAGE_BEND_BAR Boolean variable: 1=true, 0=false
IS_ANCHORAGE_HOOK Boolean variable: 1=true, 0=false
IS_ANCHORAGE_WELDED Boolean variable: 1=true, 0=false
ALPHA_1 Factor considering shape of bars
ALPHA_2 Factor considering concrete minimum cover
ALPHA_3 Effect of confinement by not welded transverse reinforcement
ALPHA_4 Effect of confinement by welded transverse reinforcement
ALPHA_5 Effect of transverse pressure
ALPHA_6 Percentage of lapped bars (DIN EN1992-1-1, 8.7.3 (2))
LB_RQD Base value of development length [m] (DIN EN1992-1-1, 8.4.3 (2))
LB_D Design value of development length [m] (DIN EN1992-1-1, 8.4.4 (1))
LB_EQ Alternative development length [m] (DIN EN1992-1-1, 8.4.4 (2))
D_MIN Mandrel diameter for longitudinal bars [m]
D_MINST Mandrel diameter for strirrups [m]
L_0 Lap length [m]
REINFORCEMENTINTENSION Boolean variable: 1=true, 0=false
REINFORCEMENTINCOMPRESSION Boolean variable: 1=true, 0=false
PERCENTAGELAPPEDBARS Percentage of lapped bars (Table 8.3)
ISBONDGOOD Boolean variable: 1=true, 0=false

Plates only

IS_FLOOR Boolean variable: 1=true, 0=false
IS_WALL Boolean variable: 1=true, 0=false
THICKNESS Thickness of Slab / wall [m]
SOFLAYERS Boolean variable: 1=true, 0=false
BASEREINFORCEMENTSYSTEM Boolean variable: 1=true, 0=false. Area reinforcement will be used for base reinforcement
BAR_LEN Minimum valid length of rebars [m]
AS_DIFF Differential As to consider a change in the reinforcement distribution [m2/m]
MERGE_LEN Maximum length to merge rebar sets [m]
MERGE_AS As to consider two reinforcement surfaces as able-to-merge [m2/m]
AS_BASE Base reinforcement [m2/m]
NO_BASE_REINFORCEMENT Create no base reinforcement
RECOGNIZE_REINFORCEMENT Consider existing reinforcement


W_FACTORS Weighting factors used in optimization
CONSTRAINTSFILE_ONLY Boolean variable: 1=true, 0=false. Ignore dialog input
CREATESINGLEBARS Boolean variable: 1=true, 0=false. Create single bars (no rebar sets)
APPLYMATCHINGXFORM Boolean variable: 1=true, 0=false. Compare exported geometry with Revit geometry to create bars in the Revit location (CDB only)
ADSJUSTTOSECTION Boolean variable: 1=true, 0=false. Adjust parametrically the reinforcement to the Revit geometry in case it is distinct to the exported model(CDB only)