Aslani Farhad, Asif Zohaib
Senior Lecturer, School of Civil, Environmental, and Mining Engineering, University of Western Australia, Perth, WA 6009, Australia.
Adjunct Associate Professor, School of Engineering, Edith Cowan University, Perth, WA 6027, Australia.
Materials (Basel). 2019 Mar 4;12(5):740. doi: 10.3390/ma12050740.
Ambient-cured heavyweight geopolymer concrete (HWGC) is a new type of concrete that combines the benefits of both heavyweight concrete (HWC) and geopolymer concrete (GC). HWGC provides proper protection from the sources that emit harmful radiations in medical and nuclear industries. Furthermore, HWGC may also be used in offshore structures for pipeline ballasting and similar underwater structures. In this study, heavyweight aggregates (magnetite) have been used and replaced by normal-weight coarse aggregates in GC at volume ratios of 50, 75, and 100% to attain heavyweight classification according to British standards. This study investigates the impacts of high temperatures on standard ambient-cured geopolymer concrete and ambient-cured HWGC through its residual properties regarding compressive and tensile strengths, mass loss, spalling intensity, and flexural strength. The residual properties were examined by heating 100 × 200 mm cylinder specimens to 100, 300, 600, and 900 °C. The results indicated that the maximum compressive strengths of 40.1 and 39.0 MPa were achieved by HWGC at 300 and 100 °C, respectively. The overall result shows that the strength of HWGC increases by increasing magnetite aggregate proportion, while the mass loss, intensity of spalling, and loss of strengths is proportional to temperature after a certain point. Minor spalling with holes and cracking was observed only at 900 °C in HWGC.
常温养护的重型地质聚合物混凝土（HWGC）是一种新型混凝土，它兼具了重型混凝土（HWC）和地质聚合物混凝土（GC）的优点。HWGC能为医疗和核工业中发出有害辐射的源头提供适当防护。此外，HWGC还可用于海上结构的管道压载及类似水下结构。在本研究中，使用了重型骨料（磁铁矿），并按50%、75%和100%的体积比取代了GC中的普通重量粗骨料，以达到英国标准的重型分类。本研究通过标准常温养护地质聚合物混凝土和常温养护HWGC在抗压强度、抗拉强度、质量损失、剥落强度和抗弯强度方面的残余性能，研究了高温对它们的影响。通过将100×200毫米的圆柱体试件加热到100、300、600和900°C来检测残余性能。结果表明，HWGC在300°C和100°C时分别达到了40.1和39.0MPa的最大抗压强度。总体结果表明，HWGC的强度随着磁铁矿骨料比例的增加而提高，而在某一温度点之后，质量损失、剥落强度和强度损失与温度成正比。在HWGC中，仅在900°C时观察到有小孔和裂缝的轻微剥落现象。
