纤维沥青碎石封层层间粘结性能及其影响因素

Interlayer Bonding Properties and Influencing Factors of Fiber Asphalt Chip Seal

为了研究纤维碎石封层层间粘结性能的影响因素，在碎石封层强度形成机理及抗裂机理理论分析的基础上，采用直接拉拔试验和正压扭剪试验评价碎石封层层间抗拉性能和层间抗剪性能，利用正交试验深入分析乳化沥青用量、碎石用量、纤维用量、纤维长度4个因素对纤维碎石封层层间粘结性能的影响。研究发现影响层间抗拉强度的程度表现为：乳化沥青用量〉碎石用量〉纤维长度〉纤维用量；影响层间抗剪强度的程度表现为：乳化沥青用量〉碎石用量〉纤维用量〉纤维长度；通过直接拉拔试验和正压扭剪试验表明，当纤维沥青碎石封层采用5～10mm集料粒径时，碎石撒布量13kg／m^2、乳化沥青洒布量2．0kg／m^2、纤维用量100g／m^2、纤维长度60mm，纤维碎石封层可取得最佳的层间粘结性能。有关结论可为纤维沥青碎石封层设计与施工提供参考。

In order to study influencing factors of bonding properties of fiber asphalt chip seal, this paper used the direct drawing test and positive pressure torsional shear test to evaluate the interlayer tensile and shear performances of fiber as phalt chip seal,based on the strength formation mechanism and crack resistance mechanism of chip seal. The main four kinds of influencing factors of the interlayer tensile and shear properties were put forward combining with orthogonal ex periment, which are, respectively, emulsified asphalt content, gravel content, fiber length and fiber content. The influence degrees of the mentioned four factors to interlayer tensile strength are shown as： emulsified asphalt content~ gravel con- tent~ fiber length 〉 fiber content; The influence degrees to interlayer shear strength are shown as： emulsified asphalt content ~ gravel content 〉 fiber content 〉 fiber length. Through direct drawing test and positive pressure torsional shear tests, the results show that： fiber asphalt chip seal can obtain the optimal interlayer bonding performance, when the fiber asphalt chip seal adopts the particle sizes which are range from 5 to 10 mm, sprinkling gravel is 13 kg/m2, emulsified asphalt is 2. 0 kg/m2, fiber content is 100 g/m2 and fiber length is 60 ram. The relevant conclusions can provide a refer- ence for design and construction of fiber asphalt chip seal.