Due to rapid urbanization and industrialization, water supply and sewer line systems are also developed relevantly. Manhole is an essential component structure of the pipeline system. Manhole is a structure constructed to accommodate the direction, dimension, differences in level, and easy of maintenance in the pipeline system. In this paper we present the result of investigations pertaining to the structural behavior of PVC sewer manhole buried underground. In the paper mechanical properties of PVC material are reported. In addition, by the finite element analysis (FEA), we confirmed that a PVC double-wall corrugated pipe manhole, when it is buried underground, is safe for the stress as well as buckling strength if the manhole is constructed within the suggested limit of buried depth.

A bake-out process using auto switchgear was carried out to evaluate the reduction effect of the concentration of volatile organic compounds (VOCs) and formaldehyde in newly-built apartments for seven days. The reduction rate of VOCs was observed as followings: 19%, 38%, 89%, 90%, and 96% for benzene, toluene, ethylbenzene, xylene, and styrene, respectively, which satisfies at the indoor air quality standards of newly-built apartment houses in Korea. The reduction rate of formaldehyde was 75%. Those results proved that the bake-out process using auto switchgear was effective for reducing indoor air pollutants.

The feasibility study of using converter slag as a solidifying agent of digested sewage sludge cake has been performed. The availability of converter slag as solidifying agent has been investigated by several trial tests. Based on the trial test results, the optimum mixing ratios of sludge cake and solidification additive are estabilished. Finally the solidification characters of sludge cake are elucidated by SEM and EDS. It is ascertained that converter slag with a small amount of quicklime enhences the solidification. From the result of pH test, overall pH of specimens tends to decrease slowly with curing time. After solidifying specimens had been cured for 7 days, these are water-cured for 24 hours. The weight and strength of all the specimens are nearly the same regardless of the mixed ratios of solidifying agent. The result of leaching tests for four heavy metal ions, Cd, $Cr^{6+}$, Pb and Cu show that the leaching strength becomes below the decision criteria of the specific wastes, respectively. The SEM observation of the delicate structure shows that needlelike crystals appear after solidification which are not observed before. From the EDS analysis, it is found that the main ingredients of needlelike crystals are Ca, Si, Al and O.

The mock-up test was carried out to evaluate applicability of unmanned coating method to prevent asbestos scattering from fiber insulation board in same vibration condition of school. Fiber insulation boards were cut into uniform size and attached in checker figure. Bang machine and rubber hammer were used to scatter asbestos sufficiently. Sodium silicate was used as a asbestos scattering inhibitor. The asbestos concentration was counted by PCM (Phase Contrast Microscope) and TEM (Transmission Electron Microscope). Asbestos concentration was 0.014 (1st day) and 0.021 (14th day) f/cm3, respectively in case of without coating. Asbestos concentration was 0.006 (1st day) and 0.008 (14th day) f/cm3, respectively in case of unmanned coating method. It was satisfied the standard of asbestos concentration in indoor air quality management law. So unmanned coating method was applicable to prevent asbestos scattering from fiber insulation board in buildings.

In this site, TBM tunnel section was composed of weak-to-moderate fine sedimentation layer, mixing claystone with gypsum. Maximum advance rate of shield TBM hits a record of digging during the tunnel work period. It is to be compared the site's cycle time data with planning stage.

Throughout this basic study of the design items for standardization in foundation structures are suggested. Reliablity-based methods of desin skills and data analysis are suggested in this paper for standardization. Limit state design method for retaining wall structures are standardized as the National Design Guide.