Shear failure experiments of concrete beams containing a weak layer were conducted with a focus on the bifurcation of shear localization appearing at the boundary between structure and soil foundation. Low-strength concrete, which is analogous to artificial soft rocks and strengthened foundation, was used to create a weak layer that caused dispersal and bifurcation of the shear localization area, resulting in ductile fracturing of members. Pulverization of hardened cement paste and gravelization (the loss of aggregate particle’s cementation) were observed in shear planes appearing in the weak layer. This confirmed the difficulty of simulating bifurcating shear localization solely by the constitutive law of concrete, which assumes firm cementation by hardened cement paste. In reference to the simulation of the disintegrated concrete slabs for bridge decks under fatigue loads, the transient model from hardened concrete to gravelized assembly was proposed, and it was successfully applied to the bifurcating shear localization of weak layers of low-strength concrete.

进行了包含薄弱层的混凝土梁的剪切破坏试验，重点是在结构与土壤基础之间的边界处出现的剪切局部化分支。低强度混凝土类似于人造软岩并具有坚固的地基，被用来形成弱层，导致剪切局部区域的分散和分叉，从而导致构件的延性断裂。在薄弱层中出现的剪切平面上观察到硬化水泥浆的粉碎和砾化（骨料颗粒胶结的损失）。这证实了仅通过混凝土的本构法来模拟分叉剪切局部化的困难，而本构法假定通过硬化的水泥浆进行牢固的胶结。