At 14:28:04 local time on May 12th, 2008, a great earthquake (M=9) occurred in the mid-west part of China. The earthquake was remarkably large in terms of the length of the activated fault, and therefore affected areas, estimates of rehabilitation costs etc. With the Grants-in-Aid for Scientific Research, Ministry of Education, Culture, Sports, Science and Technology, Japan, the network of Japanese experts in the field of seismology, geology and earthquake engineering planned to organize a team (with the first author as the leader) asking collaboration from Chinese organizations and experts with the China Earthquake Administration as its core. Japanese nominees and experts from CEA have come up to a firm conviction that China-Japan joint investigation would contribute remarkably to learning lessons from the tragic devastations in a scientific manner and therefore to quick and rational rehabilitations. Based on the authors’ first reconnaissance trip, this quick report summarizes some geotechnical aspects of the damage. [This abstract is not included in the PDF]

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   A M7.4 Earthquake jolted south of the inland of Iwate Prefecture at 8:43 JST on Saturday morning, June 14. Even though the peak acceleration of 4022 cm/s2 was the largest on records, damage to dwellings did not seem to be serious. Much more serious issues were about landslides, debris flows etc. The authors in the field reconnaissance from June 15 to 17, from July 12 to 14 and from Sept. 8 to 9 have compiled the results in forms of figures shown in this report. The latest version can be found at: http://shake.iis.u-tokyo.ac.jp/home-new/
At this moment, the drawing reflects the authors own opinions and views, but the figures will be updated with the help of more detailed field information and other experts’ opinions. [This abstract is not included in the PDF]

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   At 8:43 on June 14, 2008, the mainshock of the Iwate- Miyagi Nairiku earthquake with a JMA magnitude of 7.2 hit the mountainous areas in Iwate, Miyagi and Akita prefectures, Japan. Based on a site investigation performed four days after the earthquake, the following damage to roads in Akita prefecture was reported: a road closing caused by slope failure adjacent to a bend of a river, settlement of approach embankments for highway bridges due to large displacement of reinforced retaining walls having low stability, a failure of a road constructed by cut and fill, and a large slope failure including road embankment. [This abstract is not included in the PDF]

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   Damage to nonstructural components, suspended ceilings, in Large roof buildings, failed during the Iwate-Miyagi Nairiku Earthquake and Iwateken-Engan Hokubu Earthquake in 2008, is reported. Tohoku area has been often hit by major earthquakes in recent years and these buildings experienced such earthquakes several times. Through our investigation it was clearly noticed that the same damage have been repetitively occurring in these buildings without improvements since the governments only care the cost to the recover and nothing for the improvements. [This abstract is not included in the PDF]

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   Tokyo area has high risk of the Tokyo Inland Earthquake that may cause huge damage in the near future. In this paper, the number of heavily injured victims, who should be transported to key disaster hospitals or emergency hospitals in case of the expected Tokyo Inland Earthquake was estimated. The probability that heavily injured victims being transported to hospitals after rescue operation was described by the entropy model. Various scenarios were simulated by changing the parameters of the model in order to quantify the possible disaster situations. It was verified that not only the hospitals in the heavily affected area, but also the hospitals in the surrounding area should increase disaster response capacity and conduct countermeasures beforehand.

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   This study aims to compile and comprehensively to compare the values of shear modulus of Toyoura sand evaluated in laboratory tests by several researchers using various techniques in Institute of Industrial Science (IIS), The University of Tokyo in the last 5 years. Triaxial Compression (TC) and Torsional Shear (TS) tests were performed to observe small strain cyclic loading where is known as static measurement. Meanwhile for dynamic measurement, independent tools of Trigger Accelerometer (TA), Bender Element (BE), or Plate Transducers (PT) was employed, that was attached to triaxial and torsional apparatuses as additional tools. By considering different researchers with various techniques (specimen sizes, densities, dry and saturated conditions, apparatuses), small strain measurements on Toyoura sand yielded the values of shear modulus with no significant scattered. However, the values of shear modulus obtained with trigger accelerometer methods resulted in about 30% higher than those with bender element and plate transducers methods. [This abstract is not included in the PDF]

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   Plate type transducers were newly developed and installed in a triaxial apparatus. The performance of the plate type transducers were successfully conducted and compared with other types of dynamic measurement, such as bender element method and Trigger Accelerometer method, and static measurements. Overall, it was found that the plate transducers were less affected by the bedding error inevitably encountered with bedding errors and free from boundary conditions imposed upon trigger-accelerometer system. As such, it would be very useful to use plate transducers to conduct dynamic measurements precisely on soil samples if sample disturbance is to be avoided, especially in case of undisturbed soils. However, currently its use could only be limited to fine grained soils as the amplification level is not high enough to produce detectable output deformation for coarse grained soils. [This abstract is not included in the PDF]

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   Cyclic triaxial tests were carried out to evaluate the deformation characteristics of granular materials made from recycled glass bottles under simulated traffic loading. In the tests, effects of bedding error due to possible existence of loose zones near the top and bottom ends of the specimen that contact with rigid platens were concerned. In order to evaluate these effects on the deformation properties under cyclic loading, specimens with different heights were tested. Moreover, local deformation transducers were used in order to evaluate these effects precisely. [This abstract is not included in the PDF]

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   In order to investigate the seismic behavior of soil retaining walls, a series of model shaking tests was conducted, and generation of negative pore air pressure in backfill soil was observed. Such negative pore air pressure was possibly caused by outward wall displacement relative to the backfill soil, not by dilative behavior of the backfill soil. A simplified numerical procedure while considering the effects of the negative pore air pressure was proposed, which could reasonably simulate the measured values of the seismic earth pressure and the angle of failure plane in the backfill soil. [This abstract is not included in the PDF]

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   The KMSKS motif is the ATP binding motif for aminoacylation process of class I aminoacyl-tRNA sythetases. Various researches on the motif have been performed to reveal its catalytic properties. Most of the researches were based on motif searches and structural analyses from protein databases, and some interesting properties were discussed. Although researches based on natural proteins inform us about the contribution of natural amino acid sequences for the catalysis, they have difficulties in discussing the other alternative sequences and prohibited sequences for the motif to maintain the catalytic ability. In order to reveal such the conditions for the alternative and prohibited sequences, it is important to investigate a library of various mutants for the motif. Such the library should include inactive mutants as well as active mutants of the KMSKS motif, in order to discuss boundary conditions of active and inactive mutants. For that purpose, we build a library of more than two hundred mutants substituting the KMSSS loop, Lys204-Met205-Ser206-Ser207-Ser208, in tyrosyl-tRNA synthetase of Methanococcus jannaschii, and their degrees of catalytic were examined by the Amber suppression method. In this paper, activity degrees of all the mutants are represented in detail and some suggestion for the condition of the motif is discussed. [This abstract is not included in the PDF]

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   We demonstrated large enhancement of photoluminescence (PL) from crystalline silicon with photonic crystal (PC) nanocavities. PL intensity from the nanocavity was more than 300 times stronger than that from non-pattered Si sample at room temperature. Detail analysis of the result shows ~5-fold improvement of internal quantum efficiency. This is due to the enhanced light-matter interaction in PC nanocavities. This is the first demonstration of an improvement of light emission efficiency of crystalline silicon by engineering electromagnetic fields. We believe this result is an important step for realizing silicon-based light sources. [This abstract is not included in the PDF]

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