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（安徽建筑大學(xué)土木工程學(xué)院， 合肥 230601）

［摘要］試驗(yàn)研究了不同粒徑、不同含量聚苯乙烯泡沫混凝土(EPS混凝土)的劈裂性能。線彈性模型的計(jì)算結(jié)果表明：EPS混凝土劈裂強(qiáng)度表現(xiàn)出一定程度的粒子尺寸效應(yīng)，粒子尺寸效應(yīng)隨相對(duì)密度的降低而減小。通過劈裂試樣破壞形態(tài)可以看出，由于EPS混凝土在EPS顆粒與水泥漿體界面之間以及斷裂過程區(qū)存在大量的微裂紋，試樣在劈裂破壞中會(huì)出現(xiàn)一定數(shù)量的次生裂紋，EPS混凝土表現(xiàn)出明顯黏性特性。建立EPS混凝土抗拉強(qiáng)度黏聚裂紋模型，計(jì)算結(jié)果表明：按黏聚裂紋模型計(jì)算的EPS混凝土的劈裂強(qiáng)度也表現(xiàn)出明顯的粒子尺寸效應(yīng)，且其計(jì)算結(jié)果略高于按彈性理論計(jì)算的結(jié)果，并且兩者之間的差異隨相對(duì)密度的增加而逐漸減小。

［關(guān)鍵詞］聚苯乙烯泡沫混凝土； 劈裂試驗(yàn)； 粒子尺寸效應(yīng)； 黏聚裂紋模型； 斷裂能

中圖分類號(hào)：TU528.1      文獻(xiàn)標(biāo)識(shí)碼：A     文章編號(hào)：1002-848X(2015)08-0050-04

Study on static splitting performance of EPS concrete

Hu Jun, Ding Kewei

（College of Civil Engineering, Anhui Jianzhu University, Hefei 230601, China）

Abstract:An experimental investigation was carried out to study the splitting behavior of polystyrene foam concrete（EPS concrete）with different contents and polystyrene bead sizes. The linearelastic model calculation results show that the particle size effect  of the polystyrene foam affects the splitting strength of EPS concrete, and the particle size effect reduces with the decrease of relative density. Secondary cracks were observed in broken EPS concrete specimens. The secondary cracks were believed to be initiated from a large number of microcracks distributed in the mortar matrix around polystyrene foam beads and along the fracture pathways. It is concluded that the viscosity properties of EPS concrete has great impact on the behavior of the concrete. A cohesive crack model was established to study the splitting properties of EPS concrete. The results show that the particle size effect also exists. The solution from the cohesive crack model is slightly higher than that from elastic theoretic model, and the difference decreases with the increase of relative density.

Keywords:polystyrene foam concrete； splitting test；

particle size effect； cohesive crack model； fracture energy

*國(guó)家自然科學(xué)基金資助項(xiàng)目（11472005，51478002），安徽省自然基金重點(diǎn)項(xiàng)目（KJ2013A068），安徽建筑大學(xué)博士基金項(xiàng)目（20130103）。

作者簡(jiǎn)介：胡俊，博士，副教授，碩士生導(dǎo)師，Email：jhu0805@163.com。

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