This paper deals with a evaluation method for moisture codition in concrete by using a humidity test paper pated on concrete. The moisture evaporation rate and the moisture cotent can be estimated from the color changes of the paper. This method could be applicable to the easy judgement the period of concrete finishing. In this paper, the effects of period after pasting the paper, individual differnces of visual evaluating, temperature, the water cement ratio, the difference of member and demolding age on the relationship between the moisture evaporation rate and the color of the paper were examined. The results obtaained are summarized as follows.(1) A moisture cindition in concrete can be almost by pasting a humidity test paper on concrete approximately evalusted within 10 minutes.(2) The proposed method has nothing to do with the individual differences of visual evaluating, the testing temperature, the water cement ratio, the demolding age, the variety of member and the drying area per volume.(3) Relationship between the color estimation of a humidity test paper and the moisture evaporation rate from concrete is established.(4) Relationship between the color estimation of the paper and the moisture content of surface concrete is presented.

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Vapor permeability properties of surface finishing materials, such as paints, coatings or plasters, are important to prevent the surface from having blister or coming off, however the evaluation method is not established. In this paper, two trpes of vapor permeablility tests, which are called water cup methods, are investigated experimentally. In the tests, ground materials for finishing materials are different, one is ALC panel and the other is filter paper. Results show that time-weight change curves of the tests are linear, and it is possible to use the vapor permeability rate as an index of the vapor permeability. It is necessary to use the test method with filter paper in order to evaluate high vapor permeability materrials.

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In order to evaluate the suitable types of stainless steels for building materials in marine environment, structural simulations and exposure experiments using a test house have been performed. The experimental results show that the degrees of rusting in SUS304 and SUS316 are similar and that stainless steels whose pitting index (i.e.,[Cr]+3[Mo]+16[N]) isequal to 35 or more are required for restraint of rusting. The amount of sea salt deposit are also investigated in this work. It is shown that the sea salt deposit to roofs is ranging from 0.1 to 0.2 mg/dm^2 in C1-ions, regardless of the distance from sea, while the deposit to eaves is increasing up to apporximately 6 mg/dm^2 in C1-ion with approaching sea.

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