87 prismatic flexural steel fiber-reinforced reactive powder concrete (RPC) specimens with the size of 40mm×40mm×160mm were tested as well as 87 dumbbell-shaped axis tensile RPC specimens after being exposed to different high temperatures. The effect of steel fiber content and heating temperature on the flexural and tensile strength of steel fiber-reinforced RPC was analyzed. With the steel fiber content increasing, the flexural and tensile strength of steel fiber-reinforced RPC after high temperature improve significantly, and they increase first and then decrease with the heating temperature elevated, and the critical temperatures are 200¡æ and 120¡æ, respectively. Equations are established to express the relationship between the flexural and tensile strength of steel fiber-reinforced RPC and the heating temperature. The theoretical curves are in good agreement with the test data.

In May 15th 2010, a strong wind occurred in Suihua, which caused severe damage of building. In order to get information about damage of buildings caused by strong wind, an investigation was conducted in May 18th 2010. Through observing and interviewing, the first-hand information on the damage of rural buildings subjected to local strong wind were got. Combined with the investigation results after the disaster, an introduction to the hazard around the local strong wind region in Suihua is reported. For half-timber houses, the enclosure structure totally damaged and the gable wall was almost totally broken. For masonry-timber structure buildings, the whole structure collapsed in the strong wind. Some conclusions were got: Some buildings conforming to design code is better than what were anticipated, but the rural buildings without official design damaged serious.

For cement-soil pile composite subgrade under rigid foundation, a three-dimensional nonlinear finite element analysis is performed to analyse critical length-diameter ratio based on deformation, which is first introduced, according to replacement ratio, pile-soil modulus ratio and the modulus ratio of substratum and reinforced area. It is found that critical length-diameter ratio of cement-soil pile under rigid foundation mainly depends on replacement ratio, the impact of pile-soil modulus ratio and the modulus ratio of substratum and reinforced area is relatively little.

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Self- compacting concrete (SCC) has characteristics of good flow-ability, non-vibrating and self-compacting. It is the optimum to be used in concrete members with densely distributed steel bar and concrete is inconvenient to be vibrated. The mixture ratio of design grade of C20 and C40 SCC commonly used in project is given after trial mix. The compression stress-strain relation of SCC prism is obtained by MTS. The Mechanical property indexes of SCC are got. The ultimate compression strain of the extreme fiber is acquired by testing beam made of SCC, and the relation between the ultimate compression strain of the extreme fiber in flexural member and the strain at the peak of the stress-strain curve subjected to uniaxial compression is given.