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The internal stress calculation of continuous fiber reinforced composites under transverse loads is a complex problem. This paper established a stress calculation model based on "equal strain method", which greatly simplify the formula derivation. Three internal stress formulas under the transverse loads were derived based on the model. The first is the fiber stress formula, which shows that the ratio of fiber stress to load gradually decreases with increasing of fiber volume fraction. The second is the matrix stress formula, which shows the ratio of matrix stress to load gradually increases with increasing of fiber volume fraction. The third is the formula of average shear stress at the interface of fiber and matrix, which curve shows there is a maximum value of interfacial shear stress. The three formulas have important role for checking intensity.

The present status of reinforced concrete structure confined by FRP is introduced, and the recent technical researches of reinforced concrete beams and columns confined by BFRP are summarized. Based on those researches, the mechanical properties and calculation models are analyzed. At the same time, the seismic performance of reinforced concrete beams and columns confined by BFRP is also explored.

Solving the internal stresses of continuous fiber reinforced composite materials is a complex problem, which was studied usally by experimental or numerical calculation method. This paper proposed the equal strain method with virtual external force compensation instead of considering the shear stress in the calculation of the stress in the fiber and matrix of composite materials. By the equal strain method, the formula of longitudinal elastic modulus of continuous fiber reinforced composite materials is derived. The same result was given by other literatures with other methods, which indirectly proved correctness of the equal strain method. Further the internal stress calculation formulaes of the fiber and matrix are derived. The formulaes show that the internal stress of fiber (or matrix) is proportional to the external load and the elastic modulus of the fiber (or matrix), and is inversely proportional to the elastic modulus of the composite material.

In order to determine the fiber direction distribution statistical characteristic of short fiber reinforced concrete, this paper put forward the equal projection model. According to the isotropic assumption of large volume of short-fiber reinforced concrete, in the three-dimensional coordinate system, when the concrete loads along all coordinate axes are equal, it is believed that a representative short fiber projection components in all axes are equal. According to the deduction, the cosine of the angle of the representative fiber and the force direction is equal to the reciprocal value of the square root of 3. On this basis, as an application example, the formula for the prediction of fiber reinforced concrete elastic modulus was deduced. The formula shows that the elastic modulus of short fiber reinforced concrete is equal to the sum of 1/3 of the elastic modulus of long fiber concrete in fiber length direction and 2/3 of the elastic modulus of long fiber concrete in the vertical direction.

The current research situation of basalt fiber reinforced concrete was analyzed on the basis of the previous research results. When concrete is incorporated with basalt fiber, the compressive performance of concrete is instable, the tensile strength changes along with the fiber content, but the durability improves significantly , and the bending performance and impact resistance has more obvious improvement. According to the characteristics of chopped basalt fiber reinforced concrete, the prospect of the application of basalt fiber reinforced concrete is explored.

It has been demonstrated in previous studies that the evaluation of soundscape was influenced by not only social characteristics but also some behavioral characteristics of persons. In this study, more than 600 questionnaire survey has been undertaken at waiting halls of 4 railway stations in capital cities of China, to determine how the users’ behavioral characteristics influence their evaluation of soundscape. The results show that the relationships between evaluation of acoustics and passengers’ waiting time, rest or partners is not significant (p>0.1), but visiting times (p

Air can be dehumidified with the porous hydrophobic wall in mostly underground tunnel in constant zone of subsurface temperature. For water vapor through the wall, it must produce a concentration difference between both sides of the wall. According to this principle, a test is done combined with repair works on an underground tunnel. The hydrophobic porous mortar is scraped on geotextile, which is pasted on the painted original tunnel wall as hydraulic conductivity layer where vapor condense and water flow away. It is recognized that temperature and mass transfer rate is relative to tunnel air velocity, air temperature and partial pressure of water vapor, the temperature in constant zone of subsurface temperature and the saturated water vapor partial pressure. Comparative test results show that the condensation dew on the wall is disappeared completely, the wall dehumidifies air effectively, and saving dehumidifier power is more than 50% in normal humidity range.

Though there have been some experimental studies to discuss laws of grounding shape and grounding pressure, the acknowledged mathematics model has not established. In order to discuss the law of tire ground pressure distribution, pressure distribution models of round rectangles grounding shape and ellipse grounding shape are advanced differently. Parameters setting method and 3-D graph of different ground pressure distribution are presented, and expressions of ground area, mean ground pressure, most ground pressure and the normal stress on the ground are deduced. Results show that the grounding shape of tire is close to ellipse or rectangle as load varying, and the distribution of grounding pressure express convex or concave under different tire pressure and loading.

The feasibility of using crumb rubber concrete (CRC) in airport pavement is discussed by analyzing the capability of crumb rubber concrete. The bending property of CRC is studied by four point loading test of small-sized rubber concrete beams. Comparing with cement concrete (CC) pavement, the board thickness of CRC pavement is analyzed. The conclusions are reached that appropriate mixing of crumb rubber could satisfy strength demand and improve durability of airport pavement, and the thickness of CRC pavement is 93 percent of that of CC pavement. As a result, airport CRC pavement has longer service life and perfect cost performance.

On the basis of diffusion mechanism of crack and stress-strain of concrete, the mathematical differential formula and the pure theoretical model of stress-strain complete process of concrete are established. It is shown that stress-strain relationship of concrete is affected by Hooke’s law and diffusion mechanism of crack, and the law of which can be expressed by an exponential formula.