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Sustainable (environmentally friendly) modern construction is not limited only to use of natural and environmentally friendly materials. The concept of the construction is an important factor and that is applied to local materials, especially if they come from renewable sources. The sustainable (environmentally friendly) building principles, methods of construction from straw, the essential building requirements for construction from straw are discussed in the article. Straw as a building material used for a very long time, but this usage is often associated with certain mistrust, fears: the building will burn, the mice, rats are attacking, etc. Straw building uses raw materials which are agricultural waste. Buildings constructed from straw decompose in the end of their lifecycle and the construction waste in the area of construction is biodegradable, consequently, it is not necessary to take them away to a landfill. The evaluation of the global and Lithuanian experience of using straw and the structures in which straw are used shows, that the essential requirements can be provided if the straw and timber-framed buildings with straw as a heat insulating material are constructed properly, they use to meet the essential requirements according to the Law on Construction and the European Council and Parliament Regulation No 305/2011.

Concrete is one of the most popular construction materials in the world. The concrete properties depend from many factors. One of them is aggregates quality, which can be defined as an impurity level. The most unwanted materials in fine aggregates are clay and soil particles. These particles can impure aggregates due to irregular sands in quarry and during the digging process. In the present paper were estimated how impurity impact the properties of concrete. During the research the aggregates were impured with clay and soil particles. The change of fresh concrete workability, hardened concrete density, compression strength, water absorbability and frost resistance were evaluated. The results show that aggregates impurity with clay and especially with organic materials (soil) is very dangerous. The concrete workability, frost resistance is decreasing. The clay and soil have a different effect on hardened concrete density and compression strength. Soil decreased both parameters while well mixed clay increased these characteristics. However, generalizing all results, can be stated, that keeping the same level of concrete workability it is necessary to raise water and cement ratio and it will give strength loss effect.

Hydraulic structures are exploited in hard environmental conditions (impact of freeze-thaw cycling, ultraviolet, humidity and drying, acidity or salinity of water, abrasion etc.), so due to the impact of environmental factors some deteriorations will occur. The repeated cycles of freezing and thawing have significant effects on durability of concrete. They reducing durability, because of cracking and scaling of concrete. Using the research results of investigated hydraulic structures concrete average compression strength fck, water absorption by weight Wm, by formulae (1, 2) were calculated numbers of laboratory freeze-thaw cycles n50, freeze-thaw resistance of concrete rate F5 % and from themdurability indexprobable deterioration start time T5 % of investigated main hydraulic structures .( concrete strength fck loss in 5 % and 5 freeze-thaw cycles per year). Relationships between shaft spillway or retaining wall freeze-thaw resistance of concrete rate F5 % , durability index T5 % , and average compression strength of concrete fck were evaluated. These equations may be used for the durability prognosis of existing shaft spillways or retaining walls exploited in hydraulic structures.

Every year, huge amounts of natural resources are used to produce concrete. Sand and gravel resources are rapidly draining, therefore, it is necessary to reduce consumption. On the other hand, there are a lot of construction waste which can be reused in concrete production. One of possibilities is to use in concrete production ceramic waste. During the research the coarse aggregates were changed to ceramic bricks waste. The changes of fresh concrete workability, density, hardened concrete compression strength, water absorption and frost resistance were evaluated. The results show that ceramic waste has a negative effect to all concrete properties. Ceramic bricks waste should be used to replace coarse aggregate in a lower ratio, such as the possible option of replacing 10 % of coarse aggregates. The stoneware tiles waste show better results (Skominas et al., 2020). This waste can be used replacing up to 60 % concrete coarse aggregates. According to all results can be concluded that stoneware tiles waste is better choice for coarse aggregates production.