( 4 ) the relationship between electric emission pluse and the propagation of cracks in concrete under quasi - static loading is exhibited ( 4 )揭示了混凝土在準(zhǔn)靜載下裂紋擴(kuò)展與電發(fā)射脈沖之間的關(guān)系。
This concentration of stress further accelerates cartilage wear with thinning of outer layers and propagation of cracks and fissures in the deeper layers 集中的應(yīng)有盡有力進(jìn)一步加速外民支軟骨磨損及變薄,也加速深層碎裂和裂隙的擴(kuò)布。
It is shown that the first resonant frequency and the first anti - resonant frequency decrease synchronously due to the propagation of crack 從該曲線可以發(fā)現(xiàn),梁的第一階諧振頻率和反諧振頻率都隨裂紋的出現(xiàn)而減小,并且頻率減少量隨裂紋尺寸的增大而增加。
The results show that the thermal fatigue cracks after forming propagate preferentially in the hard phase , and the propagation of crack is stoped and dulled when it meet steel basic phase 結(jié)果表明:萌生后的熱疲勞裂紋優(yōu)先在硬質(zhì)相中擴(kuò)展,遇到鋼基體相后受阻、鈍化。
( 3 ) the methods of detecting sub - critical propagation of cracks in concrete dams are explored by use of grey system theory , motion stability theory and catastrophe theory , and three criteria for sub - critical crack propagation are given ( 3 )采用灰色系統(tǒng)理論、運(yùn)動(dòng)穩(wěn)定性理論和突變理論,研究了混凝土壩裂縫亞臨界擴(kuò)展識(shí)別方法,給出了三個(gè)裂縫亞臨界擴(kuò)展判據(jù)。
In this paper , through the statistical analysis of the random factors in the stage of sub - critical propagation of cracks , the statistical correlation equations between the two material coefficients are obtained and can be generalized . furthermore , it can be concluded that cracks propagation rate is influenced greatly by material coefficients in the condition considered in this study 本文主要通過(guò)對(duì)亞臨界裂紋擴(kuò)展階段各種隨機(jī)因素的統(tǒng)計(jì)分析,找到了可以推廣應(yīng)用的,體現(xiàn)兩材料系數(shù)之間具有強(qiáng)負(fù)相關(guān)性的統(tǒng)計(jì)相關(guān)式,并驗(yàn)證了在一定條件下,材料系數(shù)是影響裂紋擴(kuò)展速率的主要因素。