Non-destructive testing with an infrared thermography camera is focused in the paper to apply the method for field investigation for airport asphalt pavement so that stripping damages in between the pavement layers are efficiently detected. Generally the field investigation should be carried out within a few hours during nights so as not to hinder airplanes' landing and taking off. In the study, specimens modeling detached layers of asphalt concretes were made. Then they were cured under artificial day and nights' conditions with the automatic adjustment of temperature and sunlight volume in the atmosphere environment simulating room. During the nights, surface temperatures of the specimens were measured periodically with the infrared thermography camera. Based on the surface and internal temperature distributions obtained, discussions are made on what kinds of stripping damages are detectable with the infrared thermography camera and also on what sorts of pavement environment are preferable for the field survey.

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Soilbag is one of the most commonly used reinforced ground in civil engineering long ago and has being used increasingly recently in many construction fields as a reinforced ground. There are few researchers, however, related to the establishment of a numerical analysis aimed to clarify its mechanism systematically. In this research, we conduct the numerical analysis of the ground reinforced by soilbag with elastoplastic finite element analysis (FEM), to describe the results obtained from a series of two-dimensional model tests with aluminum rods. The FEM conducted in this paper is based on subloading t_ij model proposed by Nakai and Hinokio (2004). Finite deformation scheme is also adopted in the FEM due to the large deformation happened in the model tests. The numerical results show good agreement between calculation and test qualitatively and quantitatively.

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This paper describes results of geotechnical monitoring and laboratory soil tests of the execution to understand the behavior of alluvial cohesive soils according to the seawall construction for the performance design. Lots of devices, methods of measuring and evaluating data, were necessary for geotechnical monitoring system because of the instruments damage by the large ground deformation and the data lack at the stormy weather. So it could obtain the high accuracy data concerning the behavior of alluvial cohesive soils at the marine construction site. Result of analyzing monitoring data in detail, it has been confirmed that the ground consolidation is progressing along the e_˜log p curve obtained by the consolidation tests with stage loading of the soil executed beforehand. Moreover, the shearing strains of the soils are done by depth and the stratum as the seawall embankments progresses, the strain level and the speed are different and it has been understood that the deformation doesn't stop at once after loading.

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Soil improvement methods are frequently used to reduce the displacement of earth retaining wall in soft ground excavation. This paper describes the detail behavior of earth retaining wall with strut-type soil improvement in soft ground and the validity of reducing the displacement by this soil improvement method based on field measurements at three sites. Then, this paper proposes the beam-spring analytical model of earth retaining wall with strut-type soil improvement and demonstrates the effectiveness of the proposed method.

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