A wind turbine blade is presented. The blade includes an upper shell member 110 having a spar cap 130 disposed on an internal surface of the upper shell, and a lower shell member having a spar cap disposed on an internal surface of the lower shell. The spar cap 130 of the upper shell member, the spar cap of the lower shell member or both the spar caps include at least one cavity structure along a longitudinal length of the blade. A shear web 124 extends between the spar caps 130 along the longitudinal length of the blade, with a transverse end of the shear web 124 positioned in a cavity 140 of the at least one cavity structure, wherein a ratio of a width of the shear web 124 to a bond thickness of the shear web 124 with a side wall of the cavity structure 140 is between about 1:1 and about 15:1.