In this study, the effects of fibre volume fraction, fibre type, and aspect ratio on various shrinkages of the ultra-high performance fibre reinforced concretes (UHPFRCs) were experimentally investigated. Single fibre pull-out tests were conducted and the corresponding results were incorporated to explore the underlying mechanism governing the magnitudes of both autogenous and drying shrinkages. In general, the presence of randomly distributed steel fibres was found to reduce both the total and autogenous shrinkage, and more specifically, an increase in fibre volume fraction or fibre aspect ratio results in significant mitigation in both total and autogenous shrinkages. Hook-end fibres were found to be more effective in restraining autogenous shrinkage compared to straight fibres and consequently blended fibre mixes that include straight fibres were less effective at restraining shrinkage than only hooked-end fibres.

在这项研究中，实验研究了纤维体积分数，纤维类型和长宽比对超高性能纤维增强混凝土（UHPFRC）各种收缩率的影响。进行了单纤维拉出试验，并结合了相应的结果，以探讨控制自发和干燥收缩幅度的潜在机理。通常，发现无规分布的钢纤维的存在会降低总收缩率和自收缩率，更具体地说，纤维体积分数或纤维长径比的增加会显着缓解总收缩率和自收缩率。