The safety and economic section of a masonry retaining wall can be obtained by using the complexphase for structure optimization design of the wall.

This paper analyses the dissolve erosion destroy of the white scar on the surface of hydraulic structure concrete which is a kind of concrete dissolve damage occurred by the combining action of the calcium and CO2 in the cement,and the project quality and frost and thaw.

The authors of the paper have presented their new views on the correlation of compressive strength and other performance indexes of hydraulic structure concrete based on a series of normal mix proportion tests, thus providing sound bases for study of diagnosing ageing of hydraulic concrete structure and for establishing an accurate diagnosis mathematic model.

Variation of chloride-permeation resistance of concrete for ocean construction with time at early ages was studied through measurement of compressive strength,chloride permeability and pore structure.

For ocean construction, the durability of concrete for ocean construction was very important, because the caustic ions in the ocean environment would erode the concrete.

In this thesis, the influences of combinations of slag and expansive agent at different rations on the mechanical properties and durability of high performance Concrete for ocean construction were studied.