Seven coral aggregate reinforced concrete beams (CARCBs) with different types of reinforcement were designed in this study to investigate their shear behavior and calculation model. The shear behavior of CARCB was tested

and the deformation and shear capacity were investigated. The relationships of bending moment-midspan deflection

load-steel strain

and load-crack width were established. A calculation model for the ultimate bearing capacity (Vcs) of CARCB was proposed. Results show that normal section cracking load (Vcr) and Vcs of CARCB followed the rule: 316 stainless steel > common steel > zinc-chromium coated steel > organic new coated steel. The common steel had serious corrosion in the CARCB

which led to the degradation of stiffness. The CARCB crack width increased with the increase of load for different reinforcement types. In the initial loading stage

flexural cracks occurred at the midspan of the beam

which developed slowly. Inclined cracks were formed from the support to the concentrated force point with increasing loads

which widened rapidly

leading to beam failure. Therefore

with comprehensive consideration on the effects of reinforcement corrosion and high-strength concrete on the Vcs of CARCB

a calculation model for the Vcs of CARCB was proposed.