高延性地聚合物与既有混凝土界面的黏结性能

Interfacial Bonding Performance between High Ductility Geopolymer and Existing Concrete

关键词:  地聚合物  界面黏结性能  失效模式  塑性极限分析

Key words:  geopolymer  interfacial bonding performance  failure mode  plastic limit analysis

摘要:

对65个高延性地聚合物（HDGC）与既有混凝土的黏结试件进行了斜剪试验，研究了界面黏结角度、既有混凝土强度、HDGC延伸率和界面粗糙度对其界面黏结性能的影响，并基于Mohr-Coulomb屈服准则进行塑性极限分析，建立了破坏应力与界面黏结角度、内聚力和内摩擦角的计算式.结果表明：界面黏结角度对试件的失效模式起主要控制作用，界面黏结角度越大，试件的界面黏结强度越小；当既有混凝土强度提高时，试件的界面黏结强度略有降低；当HDGC延伸率为6.77%时，试件的界面黏结强度最大；随着界面粗糙度的增大，试件的界面黏结强度逐渐提高，但提高幅度呈降低趋势；建立的计算式计算结果与试验结果吻合较好.

Abstract:

Slant shear tests were carried out on 65 bonding specimens of high ductility geopolymer（HDGC） and existing concrete. The effects of interface bonding angle， existing concrete strength， HDGC elongation and interface roughness on HDGC-existing concrete interfacial bonding performance were studied. Based on Mohr-Coulomb yield criterion， the plastic limit analysis was carried out， and a formula was established to calculate failure stress using interface bonding angle， cohesion and internal friction angle. The results show that the interface bonding angle controls the failure mode. The slant shear bonding strength decreases with the increase of the interface bonding angle. As the compressive strength of existing concrete increases， the slant shear bonding strength is slightly reduced. When the HDGC elongation is 6.77%， the slant shear bonding strength is the largest. With the increase of interface roughness， the slant shear bonding strength increases， but the increasing rate decreases. The calculated results form the established formula are in good agreement with the experimental results.