The sampling test by accelerating test at load level(0.3)0Q can save time 14% in comparison with that at normal load level(0.25)Q,and the test at 0.33Q save time 25% than test at level 0.25Q.

Especially, it should also be noted that the Kaiser effect appeares at lower loading level, but the Felicity effect isincreasingly apparent with the raise of load level for two types of specimens.

The restraint distribution of a mixed crack contained in an actual structure satisfies the HRR character that the restraint level is independent of loading level and distance from crack tip.

Based on these linear expressions,a new experimental method is developed to predict the fatigue life of RC beam strengthened with CFL,that is,to predict the fatigue life by loading the RC beam with some circulatory nondestructive loads under a appointed fatigue loading level,with a recommended cyclic number of 10~1000.

In order to study the metal magnetic memory(MMM)signal character of describing the position of stress concentration,the sample with precut crack was detected by means of MMM at different tensile stress.

The specific creep of high-performance concrete (HPC) incorporated with mass fraction(the same below) of 12%, 30%, 50% and without fly ash were tested under stress strength ratios of 33% in order to clarify the effect of fly ash on creep behavior. The tests were made under controlled temperature (20±1) ℃ and humidity (60±5)% conditions.

The fretting and damage behavior of 2091 aluminum lithium alloy under radial and composite (tangential and radial) fretting against SAE-52100 steel at various loads and inclined angles were investigated in a ball-on-plate configuration.

The deformation characteristics of the fine-sandstone is studied under the loading and unloading conditions at the three different deformation-rates and the two different stress-levels. The experimental results show that there is really the plastic-loop in the deformation curve for the loading deformation curve is different from the unloading deformation curve.

We thus arrive at the fault severity factor which is fairly independent of the load level and the inertia value of the induction motors.

Experiments with a press are carried out in the regime of discrete changes in the axial load level.

Random Early Detection (RED) is a typical AQM algorithm, but it is known that it is difficult to configure its parameters and its average queue length is closely related to the load level.

Based on these, the fault severity factor which is completely independent of the inertia and load level is defined.

The damage zone in front of pre-crack tip in rubber-modified specimen (15 wt% rubber) began to form at about 13 % level of the fracture load and grew in size until 57 % load level.

The most important factors influencing the silt behaviour are porosity, confining pressure, consolidation state, cyclic loading level and number of cycles.

The effects of loading level and test temperature on rutting resistance of asphalt overlay structure were evaluated by means of multilayer specimens.

The maximum magnetoelectric effect voltage coefficient, (dE/dH)33max, of the sandwich composites is higher than that of three-phase composites at their own optimal loading level of Terfenol-D.

The emission intensity of TMA-nano-FAU treated with PMS increased with the Nd(III)-loading level.

The emission decays did not follow simple first-order kinetics and the average lifetime became longer with increasing Nd(III)-loading level.

With a view to apply the J-integral to the fracture analysis of welded joints or multilayered composites, a study of the J-integral on crack problems of layered non-homogeneous medium is made. The J-integral values for nonhomogeneous strips with a sandwiched soft layer containing a centre crack parallel or perpendicular to the bi-inaterial interfaces are computed at various load levels using elastoplastic FEM and the method for numerical evaluation of J-integral for layered media given in this paper. In the...

With a view to apply the J-integral to the fracture analysis of welded joints or multilayered composites, a study of the J-integral on crack problems of layered non-homogeneous medium is made. The J-integral values for nonhomogeneous strips with a sandwiched soft layer containing a centre crack parallel or perpendicular to the bi-inaterial interfaces are computed at various load levels using elastoplastic FEM and the method for numerical evaluation of J-integral for layered media given in this paper. In the computations, the Rice's definition of J-integral is adopted for the parallelly cracked layered strips, and a modified definition of J-integral proposed in this paper which is applicable to general multilayered medium crack problems is used for the perpendicularly craoked strips. The effect of relative width of soft layer upon the J-integral values is investigated.

The distribution of effective stress and plastic zone is analysed for compact tension (CT) specimen in 3-D deformation state using ADINA (AUTOMATIC DYNAMICAL INCREMENTAL NOLINEAR ANALYSIS) finite element program. The tendency that the effective stress and the plastic zone vary in the thickness direction and the reason that this tendency is caused are studied according to the analytical results. It is indicated that the triaxiality of the stress for Mode I fracture can not be neglected.

The author used the chevron notched short-rod specimen for fracture toughness test suggested by ISRM in his experiment. The specimen is Kallax gabbro from Sweden with diameter of 71.4mm. Under a certain load level, flourescent penetrant is injected into the crack of specimen. It is then divided into some slices with 4～8mm thick and length of each crack is measured to obtain the crack front in the specimen. It is found that crack fronts can be considered to be straight. Crack length estimated by unloading tangent...

The author used the chevron notched short-rod specimen for fracture toughness test suggested by ISRM in his experiment. The specimen is Kallax gabbro from Sweden with diameter of 71.4mm. Under a certain load level, flourescent penetrant is injected into the crack of specimen. It is then divided into some slices with 4～8mm thick and length of each crack is measured to obtain the crack front in the specimen. It is found that crack fronts can be considered to be straight. Crack length estimated by unloading tangent and secant compliances are approximately equal to the traction-free segment of crack and the measured crack length respectively. The difference between them equals the length of FPZ approximately which is about 10mm.

本实验研究采用国际岩石力学学会建议的V型切口短棒岩石断裂韧度试件,岩石为瑞典的卡莱克思(Kallax)辉长岩,试件直径为71.4mm。把试件加载至不同的载荷水平后,向裂纹注入荧光渗透剂;然后,把试件切成厚度为4～8mm的岩片并测量每一岩片上的裂纹长度,以获得各试件的裂纹前端曲线。结果表明,裂纹前端曲线可以被认为是直线。分析表明,根据卸载切线柔度估计的裂纹长度近似地等于裂纹的无表面力段长度,根据割线柔度估计的裂纹长度等于测量的裂纹长度;两者的差值近似地等于FPZ(Fracture Process Zone)长度,其值约为10mm.