本文關(guān)鍵詞： 大壩混凝土 裂縫 斷裂 隨機(jī)損傷 黏聚律　出處：《水利學(xué)報(bào)》2016年01期 　論文類型：期刊論文

【摘要】：本文基于損傷耗散能與斷裂耗散能等效原理,并假設(shè)極限應(yīng)變服從對(duì)數(shù)正態(tài)分布,建立了混凝土的微彈簧隨機(jī)損傷模型,進(jìn)一步給出了混凝土裂縫黏聚律的求解方法。依據(jù)所提方法,分別獲得了骨料最大粒徑dmax依次為80 mm和40 mm的大壩混凝土和濕篩混凝土的黏聚律的具體表達(dá)式。基于求解出的黏聚律,分別模擬了大壩和濕篩混凝土的帶切口三點(diǎn)彎曲梁裂縫擴(kuò)展全過(guò)程,并將計(jì)算得到的荷載-裂縫口張開(kāi)位移的曲線與試驗(yàn)曲線進(jìn)行了比較,兩者吻合良好,從而驗(yàn)證了模型與求解方法的合理性與有效性。進(jìn)一步采用建立的模型與方法分析了大壩混凝土和濕篩混凝土材料特征高度的合理取值范圍,結(jié)果表明:對(duì)于本文計(jì)算所用的大壩混凝土和濕篩混凝土試件,其材料特征高度值可取6~10倍骨料最大粒徑dmax。
[Abstract]:Based on the principle of equivalent damage dissipation energy and fracture dissipative energy, and assuming that the limit strain suit is logarithmic normal distribution, a random damage model of concrete micro-spring is established in this paper. Furthermore, the method to solve the concrete crack cohesion law is given. The concrete expressions of aggregation law of dam concrete and wet sieve concrete with dmax of 80 mm and 40 mm respectively are obtained. The whole process of crack propagation of three-point curved beam with notch in dam and wet screen concrete is simulated, and the calculated curve of load-crack opening displacement is compared with the experimental curve, which is in good agreement with each other. The rationality and validity of the model and solution method are verified. The reasonable value range of material characteristic height of dam concrete and wet screen concrete is analyzed by using the established model and method. The results show that the material characteristic height of the dam concrete and wet sieve concrete specimen used in this paper can be 6 ~ 10 times the maximum particle size d _ max of aggregate.
【作者單位】： 河北工業(yè)大學(xué)土木工程學(xué)院;清華大學(xué)水沙科學(xué)與水利水電工程國(guó)家重點(diǎn)實(shí)驗(yàn)室;華北水利水電大學(xué)土木交通學(xué)院;
【基金】：國(guó)家自然科學(xué)基金項(xiàng)目(51309073;51209094) 清華大學(xué)水沙科學(xué)與水利水電工程國(guó)家重點(diǎn)實(shí)驗(yàn)室開(kāi)放基金(sklhse-2014-C-02) 高等學(xué)校博士學(xué)科點(diǎn)專項(xiàng)科研基金(20131317120012) 河北省自然科學(xué)基金項(xiàng)目(E2014202257) 河北省高等學(xué)�？茖W(xué)技術(shù)研究重點(diǎn)項(xiàng)目(ZD2015028)
【分類號(hào)】：TV544
【正文快照】： 2.清華大學(xué)水沙科學(xué)與水利水電工程國(guó)家重點(diǎn)實(shí)驗(yàn)室,北京100084;3.華北水利水電大學(xué)土木交通學(xué)院,河南鄭州450011)1研究背景混凝土材料抗拉強(qiáng)度僅為抗壓強(qiáng)度的1/8~1/12[1],因此,當(dāng)環(huán)境變化和荷載等作用下產(chǎn)生的拉應(yīng)力超過(guò)混凝土自身抗拉強(qiáng)度后會(huì)出現(xiàn)裂縫。對(duì)于重要水工混凝土建，

本文編號(hào)：1443018