Effects of superabsorbent polymer particles on flexural properties and self-healing behavior of ECC  

高吸水性树脂对水泥基复合材料弯曲性能和自愈合行为的影响（英文）

作　　者：Deng Hanwen 邓涵文(东南大学交通学院,南京210096)

机构地区：[1]School of Transportation,Southeast University,Nanjing 210096,China

出　　处：《Journal of Southeast University(English Edition)》2018年第1期95-103,共9页东南大学学报（英文版）

基　　金：The National Natural Science Foundation of China(No.51278097);Start-up Grant Provided by Nanyang Technological University(No.M4081208)

摘　　要：In order to improve the self-healing behavior and the recovery of mechanical properties of engineered cementitious composites(ECC),the approach of incorporating superabsorbent polymer(SAP)in mixtures is investigated.The rapid water penetration test and four-point bending test were conducted to evaluate the effects of self-healing on the water permeability and mechanical properties of pre-damaged ECC.The self-healing process and self-healing products were observed by the environment scanning electron microscope(ESEM)and energy dispersive X-ray spectroscopy(EDS).The experimental results show that all ECC mixtures exhibit excellent flexural capacity,meanwhile maintaining a crack width below 50μm.The incorporation of SAP particles in ECC can apparently improve the mechanical recovery of ECC mixtures after 10 healing curing cycles,such as flexural deformation and flexural stiffness.The flexural stiffness of ECC containing 4%SAP particles after self-healing can be recovered to 80%.The self-healing test results show that when the water permeability of ECC mixtures incorporating SAP particles is close to zero,only three healing cycles are needed.When ECC incorpora ting more SAP particles,the accelerated self-healing process can be finished in the first three cycles,and self-healing product is mixed Ca(OH)2/CaCO 3 with CaCO 3 being a major component in the later stage.It is,therefore,feasible to produce ECC materials incorporating SAP particles,while simultaneously maintaining higher material ductility and self-healing behavior.为了提高工程水泥基复合材料(ECC)的自愈合行为和力学恢复性能,将高吸水性树脂(SAP)定量地掺加在混合物中.采用快速渗透试验和四点弯曲试验研究了自愈合对已破损ECC试件的透水性和力学性能的影响,利用环境扫描电镜和X射线能谱分析研究了ECC的自愈合过程和自愈合产物.实验结果表明:所有ECC试件均具有良好的弯曲能力,同时还能维持裂缝宽度在50μm以下;经过10个养护循环后,结合有SAP的ECC试件的力学恢复性能如弯曲变形和弯曲韧性得到明显提高;掺量为4%SAP的ECC试件,其弯曲韧性在自愈合后可恢复到80%.此外,自愈合试验结果显示:在掺加SAP的ECC混合物中,当其渗透性接近为0时,仅需要3个愈合循环养护;当ECC试件掺加更多SAP颗粒时,其自愈合过程能加速在头3个循环内完成;自愈合产物为Ca(OH)_2和CaCO_3的混合物,且后期以CaCO_3为主要产物.研究表明:利用SAP材料制备高延性、高自愈合的ECC是可行的.

关 键 词：engineered cementitious composites(ECC) SELF-HEALING superabsorbent polymer(SAP) mechanical property 

分 类 号：U414[交通运输工程—道路与铁道工程]