## 1 Introduction  
During the last few decades, most countries have intensified their efforts to mitigate the adverse effects of the construction industry on the environment. From this point of view, developing and implementing effective technological solutions to produce concrete with improved performance parameters, especially fracture properties, is essential. The rational approach to properly selecting concrete constituents results in producing more durable materials and, in addition to environmental benefits, reducing investment costs. This corresponds to the requirements of sustainable construction. With the implementation of standards from the ISO 14000 family, the awareness of the Life Cycle Assessment (LCA) methodology has grown globally. This methodology serves as an assessment tool that yields consistent analytical outcomes, addressing various environmental issues [1]. Supplementary cementitious materials (SCMs), especially aluminosilicates (fly ash, zeolitic tuff, silica fume, etc. ), offer numerous advantages to the transportation infrastructure and construction sector [2; 3; 4]. These materials are highly beneficial due to their availability, cost-effectiveness (especially when easily accessible), long-term mechanical properties, and ability to enhance durability [5; 6]. Of particular interest is zeolitic tuff, which exhibits significant pozzolanic activity [7; 8]. Abundant mineable zeolite deposits are found across numerous countries around the world. The yearly production of natural zeolites has remained relatively stable for the past decade, with an approximate output of 3 million tons. The use of zeolitic tuff in concrete has been proven to enhance its durability significantly [9; 10], along with its mechanical [11] and mass transport [12] properties. Previous studies [13; 14] have demonstrated that replacing 10% by mass of cement with natural zeolite and using chemical admixtures leads to enhanced concrete properties and improved durability. For industrial and civil construction, it is crucial to find new additives to concrete that would satisfy operational parameters [15; 16; 17; 18; 19; 20; 21]. [PERSON] et al. [22] studied modified zeolite's influence on the freeze-thaw and de-icing salt resistance of hardened cement paste; their results showed a significant improvement in density, strength, and frost resistance as well as resistance to the adverse effects of salts. Study [23] found that the frost resistance of zeolite-containing concrete exhibits a slightly lower performance than control concrete during the initial phase of freeze-thaw cycles. As the cycles progress, the frost resistance of zeolite-containing concrete significantly surpasses that of conventional concrete, which is related to the internal curing effect. However, the above-mentioned studies did not study the joint effect of the use of both zeolite and air-entraining agent. The water absorption and freeze-thaw resistance of hardened concrete are essential parameters for bridge and pavement applications. According to [PERSON] et al. [24], it is predominantly influenced by factors such as the size, type, and distribution of pores and capillaries in concrete. Closed and tiny pores in such a structure are not entirely saturated with water, resulting in what is known as reserve pores. During freezing conditions, water may migrate towards these reserve pores, creating voids that accommodate ice expansion. Air-entraining admixtures proved to be a reliable method to improve fresh-concrete properties [25] and hardened-concrete performance, especially in a freeze-thaw environment [26]. However, there is a lack of studies regarding the influence of entrained air on the fracture parameters of concrete. It is well known that concrete failure involves the formation and propagation of cracks: it exhibits a quasi-brittle behavior, combining characteristics of both brittleness and elastic-plasticity [27].