One of the important issues in the production of concrete is environmental variability that affects the concrete and elements constructed from this material. Due to the importance of different characteristics of concrete in short- and long-term conditions, this article aims to investigate the influence of initial temperature conditions of self-compacting concrete on its long-term characteristics and determine the initial optimal temperature of concrete. For these purposes, several experiments under three temperature conditions of 5, 20, and 40 degree-of-Celsius were conducted to evaluate the rheology and Mechanical Properties of fresh concrete in the range of 7 and 28 days. In these experiments, alternative mineral admixtures of cement such as micro-silica, fly ash, and zeolite were used to build the concrete specimens. Results demonstrate that the Mechanical Properties of the specimens increase with increasing initial temperature in the short term, while such Properties significantly decrease in the long term compared to the specimens constructed under lower initial temperature. Moreover, the fluidity of self-compacting concrete increases with increasing initial temperature.

Irregularities are inherent to virtually all fibers, including the conventional textile fibers, the high-performance brittle fibers and newly developed nano-fibers. These irregularities can fall into two main categories: dimensional or geometrical irregularity (external) and structural irregularity (internal). For natural fibers such as wool, diameter variation along fiber length is a typical example of fiber dimensional or geometrical irregularity, while the presence of flaws and defects within a fiber signifies structural irregularity. The irregularities of fibers are bound to have major impact on the Mechanical behavior of fibers. In recent years, there has been a growing awareness of the importance of this particular fiber attribute – fiber irregularity, particularly the within-fiber diameter variation. Instruments have been developed to accurately measure fiber diameter variations. In addition, with the development of computing technology, numerical modeling technique has been applied to examine the impact of fiber irregularity on fiber Mechanical Properties. This paper reviews research progress in the area of fiber geometrical irregularity and its effect on important fiber Mechanical Properties.

To determine some Mechanical Properties of garlic bulb and its cloves, some Mechanical tests was performed on a variety of Talesh local garlic at three levels of storage period with 70-day intervals. Mechanical tests are performed on three levels of loading speed and three levels of storage period. Compressive tests were performed on bulb, cloves, and on cylindrical samples taken from the tissue of garlic cloves. According to analysis of variance based on factorial experiment in randomized complete block design, the value of module of elasticity, maximum force required to rupture and toughness of cloves were measured respectively 2.762MPa to 7.091MPa, 105.043N to 167.27N and 62.358mJ/mm3 to 101.44mJ/mm3 and also the value of young module of elasticity, the maximum force required to rupture and toughness of cylindrical samples taken from tissue of garlic cloves were measured 3.368MPa to 6.981MPa, 12.606N to 25.762N and 0.173mJ/mm3 to 0.33mJ/mm3 respectively. The ranges of value of force required to loosen the bulb, while loading along the height and width direction, were measured 127.023N to 228.001N and 45.52N to 106.97N respectively.

Structural fire safety capacity of concrete is very complicated because concrete materials have considerable variations. In this paper, constitutive models and relationships for concrete subjected to fire are developed, which are intended to provide efficient modeling and to specific fire-performance criteria of the behavior of concrete structures exposed to fire. They are developed for unconfined concrete specimens that include residual compressive and tensile strengths, compressive elastic modulus, compressive and tensile stress-strain relationships at elevated temperatures. In this paper, the proposed relationships at elevated temperatures are compared with experimental result tests and pervious existing models. It affords to find several advantages and drawbacks of present stress-strain relationships and using these results to establish more accurate and general compressive and tensile stress-strain relationships. Additional experimental test results are needed in tension and the other main parameters at elevated temperatures to establish well-founded models and to improve the proposed relationships. The developed models and relationships are general, rational, and have good agreement with experimental data.