## 1 Introduction  
Creep is a significant mechanical behavior of cementitious materials that causes time-dependent deformations throughout a structure's service life [1; 2; 3; 4; 5; 6]. This phenomenon occurs when deformation grows excessively under constant stress [7]. Understanding the creep mechanism in cementitious composites is a challenging task due to the environmental influences and complexity between creep and shrinkage [8] as in the absence of an applied load, shrinkage also causes the material to deform [9]. However, the uncertainty between these processes offers the opportunity to investigate the mechanical behavior of cement-based materials at various time and length scales. Research over decades has been dedicated to understanding short- and long-term creep effects, in concrete [10]. Short-term creep is identified by an instantaneous strain and elastic response of the material [11; 12]. Alternatively, long-term creep occurs when the calcium-silicate-hydrate (C-S-H) of cement paste begins to slide and rearrange leading to water diffusion that can form microcracks [13]. These small microcracks transform into larger cracks over time which allow water and sodium to seep in and corrode the reinforcement inside [14]. Additionally, creep-induced cracks in prestressed concrete structures have notably larger deflections and weaker bearing capacity [15; 16]. These types of failures have been responsible for over billions of dollars needed to maintain reinforced concrete structures [2]. Fiber additives in the form of micro- and nano-fillers in cement paste are being implemented to limit creep and enhance the overall mechanical performance of the binder [17]. [PERSON] et al. [18] studied the effects of fly ash addition into cement paste on the creep response under several loading conditions. Microindentation tests revealed that capillary water has significant influences on creep compliance [18; 19]. Meanwhile, [PERSON] et al. determined that steel fiber-reinforced cementitious composites have better creep performance than normal cement paste [20; 21]. Several other studies introduce silica fume and other reinforcements to improve the creep response of the system [22; 23; 24; 25]. Recently, researchers have been interested in naturally occurring materials, such as wollastonite [26; 27; 28]. This raw mineral is found in many regions of the world and has shown an increase in production over the last two decades [29; 30]. Wollastonite is a non-harmful material used in ceramics, paints, and polymers [31; 32]. It is recognized for exhibiting high strength, water, and heat resistance [30; 33]. The chemical structure of wollastonite contains natural chains of calcium and silicate-based inorganic compounds which is chemically very similar to calcium-silicate-hydrate (C-S-H) in cement paste. Thus, the interface between these two materials presents better chemical compatibility and bonding between fiber and matrix. Previous studies have shown significant improvement in mechanical performance with the incorporation of wollastonite fibers in cement-based composites [34; 35; 36]. [PERSON] et al. found that wollastonite fibers prevent shrinkage in hardened cement paste [37; 38]. [PERSON] et al. [39], performed microindentation experiments and finite element simulations that showed about a 33% increase in fracture toughness when 10% mass-based cement replacement by wollastonite is considered. [PERSON] et al. [40] performed multiscale numerical simulation to elucidate the influence of wollastonite microfibers on the dynamic compressive response of mortars and the results suggest about a 45% increase in dynamic energy absorption capacity with 10% mass-based replacement of cement by wollastonite fibers. While these previous studies focus primarily on the mechanical response of wollastonite-fiber-reinforced cementitious composites in terms of compressive/flexural strength and fracture under static and dynamic loading conditions, no study has been conducted thus far to evaluate the creep response.