Influence of glycol, which is the main composition of the most frequently used aircraft dicer, on the freeze-thaw durability of Portland cement concrete were investigated. Freeze-thaw durability of Portland cement concrete was tested by accelerated freeze-thaw test. Four kinds of solutions, namely tap water, 3.5% NaCl solution, glycol solutions and a LBR-A type commercial aircraft deicer were employed to be the freezing-thawing mediums. Results show that freeze-thaw durability of concrete exposed to glycol solutions is closely related to the solution concentrations. Failure of concretes exposed to 3.5% glycol solution is similar to that of those exposed 3.5% NaCl solution, which are attributed to serious surface scaling. While damage of concrete exposed to 12.5% and 25% glycol solutions are postponed, and the durability of concrete are increased. Compared with glycol solution, the commercial aircraft deicer demonstrated much more negative effect to concrete freeze-thaw durability, and the degree even exceeds 3.5% NaCl solution. Consequently, the commercial aircraft deicer is not a kind of environmental friendly deicer as usually considered.

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Abstract:In the construction industry, according to the study on the skin effect of some scholars, showing the skin effect of the wooden structure not only has important significance in strengthening the structural strength and reduces the use of building materials, but also the use of skin effect in a small vibration shows better stiffness and improves the comfort when live in the wooden architecture. Because of wood environmentally friendly, wooden architecture has typical of the green ecological characteristics of wooden architecture increasingly welcomed by the people. The article will study the skin effect of bamboo waferboard wooden architecture. Analysis the models of the wall and wooden architecture which consider skin effect and do not consider the skin effect by using finite element software The working principle of the skin effect is: the enclosure plate and purline and board and board are connected by different fasteners, forming a series of partitions with purline as its rib. This board has quite a large stiffness in the plane, is similar to the web, a thin-walled deep beam purlin is similar to the stiffener thin-walled deep beam, plate connection around the wall beam or purlin is similar to the flange of a thin-walled deep beam, which can be used to transfer plate plane shear, all sorts of plate under in-plane loading . The skin structure is mainly composed of the skin plate, frame structure and fittings. the structure of the monskin plate Wood structure of pedal mainly USES plywood, plywood is by the logs by wood square plane rotary cut veneer or cut it into two sub-companies named seaport, reoccupy adhesive agglutination of three layer or layers of plate material, usually with an odd number of veneer, and make the fiber direction perpendicular agglutination adjacent veneer. A set of veneer usually is formed by the vertical forming of the blank in the direction of the adjacent layer of wood grain. Usually the plate and the inner plate are configured on both sides of the center or the core of the board. The plate is crisscrossed with wood grain in the direction of wood grain, and it is compressed by heating or not heating. The number of layers is usually odd, and the few have even Numbers. The physical and mechanical properties of the transverse direction are small. Commonly used plywood type has 3 plywood, 5 plywood and so on. Plywood can improve wood utilization and is a main way to save wood. The following are some common plywood, as shown in figure 1, figure 2, figure 3, as shown