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Acting as a surface which is supposed to tolerate several reloading of heavy axes, pavement shall hold enough resistance against failures. Fatigue phenomenon is one of the most important causes of weakness in road pavement, which is occurred due to reloading of it. Many laboratory researches are carried out with the purpose to enhance fatigue life of asphalt concrete mix, in which researchers have tried to improve quality of asphalt concrete mix against load carrying transportation vehicles. During recent years, additives like polymer, iron powder, hydrated lime, glass wastages, crumb rubber and brick powder are also considered for improving tar and, consequently, asphalt mix properties. Generally, hot-mix asphalt (HMA) mixtures consist of three components: mineral aggregates, asphalt binder and air voids. It is well recognized that mineral fillers play an important role in the properties of mastics and hot-mix asphalt (HMA) mixtures. Better understanding of the effects of fillers on the properties of mastics and HMA mixtures is crucial to good mix design and high performance of HMA mixtures. In this stydy, the effect of brick powder on fatigue parametrs have been investigatedFiller content for mix design should be determined based on the overall performance of HMA mixtures.It has been recognised with growing concern that agricultural and industrial wastes are increasingly produced in large volume. In order to reduce environmental hazards and conserve natural resources, the use of waste materials in highway pavements would be extremely effective in terms of recycling waste materials. The main purpose of this study was to investigate the effects of waste materials as filler on the performance of hot mix asphalt (HMA) mixtures.It is well recognized that mineral fillers play an important role in the properties of mastics and hot-mix asphalt (HMA) mixtures. Better understanding of the effects of fillers on the properties of mastics and HMA mixtures is crucial to good mix design and high performance of HMA mixtures. Laboratory experiments were conducted to investigate the effect of different fillers on properties of mastics and HMA mixtures. The properties of HMA mixtures were investigated by Marshall, indirect tensile stiffness modulus and indirect tensile fatigue tests. The results indicated that WBP mixtures exhibited higher fatigue life and better performance than control mixtures. With the increase of filler content, some properties of HMA improved while others decreased. The effects of filler were exerted on HMA mixtures through the mastic. Fillers with rough particle texture (such as manufactured sand) tend to increase the stiffening effect of the mastics and mixtures. Considering the overall effects of filler on the properties of HMA mixtures, a filler content range would be required in order to ensure the performance of the mixtures. Waste materials can be mainly regarded as the following classifications: (a) industrial wastes such as cellulose waste, slag, bottom ash and fly ash; (b) municipal/household wastes such as incinerator residue, scrap rubber and waste glass; (c) mining wastes such as coalmine refuse and (d) construction and demolition Based on the results, in consequence of increased awareness of environmental issues and natural resources constraints, the studied waste materials can be advantageously utilised in road construction.

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In this research, influence of foam filling technique in sandwich beams with expanded metal sheet as core by using lightweight rigid polyurethane foam is investigation. Relationships between the force and displacement at the midspan of the sandwich beams are obtained from the experiments. Three types of Steel lattice cores both bare and foam-filled were subjected to quasi-static. The performance of sandwich structures with expanded metal sheets as core were studied under transverse bending. In the following, by studying the orientation of the core layers to evaluation the impact parameters, including Specific Energy Absorption (SEA) as discussed testing purposes. the energy absorbing system can be used in the aerospace industry, shipbuilding, automotive, railway industry and elevators to absorb impact energy. experimental results showed that foam filling technique can significantly increase specific absorbed energy. Results of three point bending crushing tests showed that the SEA of foam-filled sandwich beam increased by 74 %, comparing to the hollow beam. Also, appropriate orientation of core in the sandwich beam caused to increase the specific energy absorption by 66.5%. Finally, appropriate geometric parameters and the best examples of criteria considered with respect to the objectives, are introduced.

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In this research, an influence of topology optimization in energy absorption of lattice core sandwich beams by using ABAQUS software was an investigation. Relationships between the force and displacement at the midspan of the sandwich beams were obtained from the experiments. Two types of Steel lattice cores with three cell orientation were subjected to the low-velocity impact test under three-point bending. The core of sandwich beams was made from expanded metal sheets and a topology optimization with Solid Isotropic Microstructure with Penalization (SIMP) method was used to remove the redundant expanded metal cell. In the following, by studying the topology optimization to evaluate the impact parameters, including Specific Energy Absorption (SEA), as discussed testing purposes. The energy absorbing system can be used in the aerospace industry, shipbuilding, automotive, railway industry and elevators to absorb impact energy. Experimental and numerical results showed that topology optimization could significantly increase specific absorbed energy. Results of three-point bending crushing tests showed that the SEA of a sandwich beam with optimal core structure increased between 45% and 94% compared to the initial design structure of the core. In addition, appropriate orientation of expanded metal cell in the core of sandwich beam caused to increase the specific energy absorption by more than 90%. Finally, an appropriate optimal geometric structure with three tape of volume fraction and the best examples of criteria considered with respect to the objectives were introduced.

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   The Contract of Sale as one of the most exchanged contracts requires each parties to perform The Obligations against the other Party. According to the Vienna Convention, the Seller is required to perform the Obligations against the Buyer. The question is that whether Usage is effective in determining of The Obligations of the Seller based on the Convention on the International Sale of Goods? Parties to the contract are not required to predict and specify all details of the contract, It is sufficient to reach an agreement on the elements of the subject matter of the contract and Usage and Supplementary law determine other details and the effects of contract (specifying the rights and obligations of the parties about it). Article 220 and 225 of the Civil Code confirms this claim. Usage also have an important role based on the Vienna Convention 1980, because, in the Convention on the International Sale, in addition to being, the parties are bound by any usage to which they have agreed and by any practices which they have established between themselves, are considered, unless otherwise agreed, to have impliedly made applicable to their contract or its formation a usage of which the parties knew or ought to have known and which in international trade is widely known to, and regularly observed by, parties to contracts of the type involved in the particular trade concerned. In this Research will examine the effect of Usage and Practice in determining the Obligations of the Seller. By induction under the provisions of the Convention, we get the general result  that, in the assumption of the absence of an agreement on the determination of sellers obligations, according to Article 9 of the Convention, Usage and Practice will undoubtedly determine the sellers obligations.Therefore, in the absence of an agreement between the parties on the commitment to certain Usages and the lack of Practice among them regarding the Sellers obligations, if the conditions of the Usages referred to in paragraph 2 of Article 9 of the Convention exist, the seller will be obliged to comply with it. Finally, in the absence of decisive rules, the Seller is bound to fulfill its obligations, In accordance with the Supplementary Provisions of the Convention. The same situation exists in the Iranian law.