brittleness index

According to the discuss of brittleness and brittleness index for concrete, as a true brittle material from microstructure point, magnitude of brittleness of concrete is relate to the dimension of plastic zone.

对混凝土脆性及脆性指标分析的结果表明，混凝土作为微观真脆性的材料，其脆性大小最终应归结为塑性区尺寸的大小；

Experimental results show that brittleness index values of rubberized concrete whose coarse aggregate replaced by rubber powder or rubber block were lower than that of normal concrete, which meant that rubberized concrete had better ductility performance.

试验数据表明，与普通混凝土相比，分别用橡胶粉或者橡胶块代替粗骨料的橡胶混凝土的脆性指数有不同幅度的降低，材料的延性有所改善。

Because brittleness behavior of concrete is influenced by size of specimen, brittleness index must not including size effect. Most existing brittleness index is not exact for its including parameters vary with size.

由于试件的尺寸显著影响混凝土的脆性行为，脆性指标必须不包含尺寸因素，即不随试件尺寸发生改变，现有的绝大多数脆性指标由于所含参数具有尺寸效应而不确切；

And it is found that the model can duplicate the transference of deformation mode from the strain softening under the low confining pressures to the strain hardening under the high confining pressures; and the brittleness index gradually reduces when the confining pressure is increased.

模拟结果表明：这一模型可以模拟低围压下的应变软化到高围压下的应变硬化现象，并且脆性指数随着围压的增大而逐渐减小。

Upon loading, unloading, and reloading on prepared cylindrical specimens, the hysteresis loops were drawn and brittleness index values were obtained.

对橡胶混凝土圆柱体进行循环加载，得到它们的滞回曲线，从而求得橡胶混凝土的脆性指数。

Numerical examples show that high brittleness index can improve the bearing capacity stability of the structure and the existence of crack set up in advance will increase the ductility of the structure, but it may result in the reduction of ultimate bearing capacity.

数值计算表明：增加脆性指数可以提高结构的承载稳定性；初始预制缝可以增加结构延性但会降低极限承载力。

In the paper a brittleness index B is proposed and used to describe the brittleness variety of geomaterials under loading or unloading conditions.

建议了一个可以描述材料脆性变化的脆性指数B，并验证了B指标能较好地描述岩土材料在加卸荷时的脆性变化。