Strut-and-tie model

These forces were then applied to a model that could accurately represent how the loading would be shared between the four beams in a given load combination, as two of the beams are 6.6 m deep and the other two beams are 11.6 m deep. Once the force distribution was established, the forces were placed in the strut-and-tie model. 

The strut-and-tie model was developed and the internal force distribution was determined. Concrete stresses were checked to ensure they were below the allowable code criteria, and reinforcing steel was placed in the tension tie regions. The analysis yielded a maximum factored tie force of 21,500 kN, equivalent to the breaking strength of strength of approximately nine 2" diameter full locked coil ropes. 

ACI 318 Sections RD.5.2.9 and RD.6.2.9 state that in sizing the anchor reinforcement, the use of strength reduction factor (j) = 0.75 is recommended as is used for the strut-and-tie models (ACI 318 Section 9.3.2.6), implying that the use of the STM design approach in designing anchor reinforcement is an acceptable design approach. 

Alternate Model for Tension Loading Using the Strut-and-Tie Model... 

FORCE DISTRIBUTION IN THE TRUSS MODEL AFTER DIVIDING BY = 0.75 (SECTION 9.3.2.6 OF Aa 31S08 F( THE STRUT-AND-TIE MODEL IS 0.75) ... 

Vollum RL, Newman JB (1999) Strut and tie models for the analysis/design of external beam-column joints. Mag Concr Res 51(6) 415-425 Walker SG (2001) Seismic performance of existing RC beam-column joints. MSc thesis. University of Washington... 

The strength of shear keys can be derived from sophisticated models such as strut and tie ones or simplified ones, usually based on the shear friction concept. Bozorgzadeh et al. (2006) proposed the following relationship for the nominal capacity of a shear key ... 

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