Research at structural concrete laboratory

Shear strength of concrete slabs and shells

The shear strength can become a controlling factor for some configurations of slabs without transverse reinforcement (i.e. slabs subjected to very intense distributed loads, foundation slabs, retaining walls, slabs subjected to concentrated loads in the vicinity of linear supports, shells in the vicinity of supports, ...)
 
The Critical Shear Crack Theory, initially developed for the punching of flat slabs, also allows considering these cases with a very good accuracy. This model was adopted in the Swiss SIA 262 code (2003 and 2013). Furthermore, an experimental and analytical test campaign has demonstrated that shear has a strong influence on the plastic deformation capacity of members without transverse reinforcement.
 
Research currently under way focuses on a better understanding of the behaviour of elements subjected to uniform loading (with a portion of the load being directly transferred to the supports), the case of concentrated loads acting in the vicinity of linea supports (capacity of redistribution of internal forces) and the fatigue strength of bridge deck slabs.
 

Reference Publications

Strength of one-way slabs

  • Fernández Ruiz M., Muttoni A., Sagaseta, J.Shear strength of concrete members without transverse reinforcement: A mechanical approach to consistently account for size and strain effects, Engineering Structures, 2015, pp. 360-372.
  • Muttoni A., Fernández Ruiz M., Shear strength of members without transverse reinforcement as function of critical shear crack width, ACI Structural Journal, V. 105, No 2, Farmington Hills, USA, 2008, pp. 163-172.
  • Influence of shear on the deformation capacity in bending

  • Vaz Rodrigues R., Muttoni A., Fernández Ruiz M., Influence of Shear on Rotation Capacity of Reinforced Concrete Members Without Shear Reinforcement, ACI Structural Journal, V. 107, n° 5, Reston, USA, 2010, pp. 516-525.
  • Interpretation of shear-transfer actions

  • Cavagnis F., Fernández Ruiz M., Muttoni A., Shear failures in reinforced concrete members without transverse reinforcement: An analysis of the critical shear crack development on the basis of test results, Engineering Structures, pp. 157-173, UK, 2015.
  • Campana S., Fernández Ruiz M., Anastasi A., Muttoni A., Analysis of shear-transfer actions on one-way RC members based on measured cracking pattern and failure kinematics, Magazine of Concrete Research, 19 p., UK, 2013.
  • Shear strength of shells and arch-shaped members

  • Campana S., Fernández Ruiz M., Muttoni A., Shear Strength of Arch-Shaped Members without Transverse Reinforcement, ACI Structural Journal, V. 111, USA, 2014.
  • Slabs with concentrated loads in the vicinity of linear supports

  • Natário F., Fernández Ruiz M., Muttoni A., Experimental investigation on fatigue of concrete cantilever bridge deck slabs subjected to concentrated loads, Engineering structures 89, 2015, pp. 191-203.
  • Natário F., Fernández Ruiz M., Muttoni A., Shear strength of RC slabs under concentrated loads near clamped linear supports, Engineering structures 76, 2014, pp. 10-23.
  • Vaz Rodrigues R., Fernández Ruiz M., Muttoni A., Shear strength of R/C bridge cantilever slabs, Engineering structures, Vol. 30, Netherlands, 2008, pp. 3024-3033.
  • Members with distributed loads and/or variable depth

  • Pérez Caldentey A., Padilla P., Muttoni A., Fernández Ruiz M., Effect of load distribution and variable depth on shear resistance of slender beams without stirrups, ACI Structural Journal, V. 109, USA, 2012, pp. 595-603.
  • Fatigue in shear of one-way slabs

  • Fernández Ruiz M., Zanuy C., Natario, F., Gallego, J. M., Albajar, L., Muttoni A.Influence of fatigue loading in shear failures of reinforced concrete members without transverse reinforcement, Journal of Advanced Concrete Technology, V. 13, 2015, pp. 263-274.