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The cost reduction of hydrogen stations is a must in order to spread fuel cell vehicles. Generally, the PSA device in the hydrogen station occupies 30% of the construction cost. We have already proposed the cost reduction by replacing the PSA and CO shift converter with a membrane reactor to which CO2 selective facilitated transport membrane is built in 2011. Although the CO2 facilitated transport membrane achieved the CO2/H2 selectivity of 100 or more even if the operation temperature was 160°C, the durability was poor. Therefore, it is necessary to improve the heat resistance and the rate of reaction between carrier and CO2 furthermore so that it can be adopted for the membrane reactor. In order to improve the membrane performance at 160°C by keeping high water content of membrane, graphite rubbish was added to the membrane as it was expected to function as grain for water absorption. As a result, the CO2 selectivity of the membrane improved more than that of the previous membrane by 3 times.

The hydrogen station in Japan is only 17 points though Toyota began to sell FCV from 15th November, 2014. The main reasons for which the spread of HS is late are a high construction cost and the indefinitely of spread prospect of FCV. However, it became clear that FCV in Japan spreads surely because the order for FCV exceeded 1000 from release in one week. The remaining problem is to reduce the cost of construction of 300 million yen. Therefore, we proposed membrane reactor composed of the reformer and the CO2 facilitated transport membrane to reduce the construction cost. It is necessary to achieve heat resistance of 160°C so that it is adopted for the membrane reactor. Therefore, we aim to optimize the operating condition (humidity, partial pressure of CO2 and differential pressure) of NDP to obtain the indicator of the heat resistance improvement at first. As a result, it is clear that the optimum operating condition of NDP is 80% of relative humidity, 200kPaG of the differential pressure and 40kPaG of the CO2 partial pressure.

Polymer cement mortar exhibits high gas shielding performance and adhesiveness by formation of polymer film. By these reasons, polymer cement mortar is used as material of the repair and the reinforcement of reinforced concrete structure. As it is attached to surface of concrete, however, sufficient wet curing is difficult in many cases. Therefore, the study has been aimed at clarifying impacts of quantity of polymer and cement hydration on gas shielding performance of polymer cement mortar. The gas shielding performance was evaluated based on gas diffusion coefficient in the study. Results of the study are described as follows. Quantity of the polymer in a range from 0 to 60kg/m³, while gas diffusion coefficient was little affected when quantity of polymer was within the range from 0 to 20kg/m³, it was decreased when the quantity of polymer increased to above the range. In addition, cement hydrate increased and gas diffusion coefficient was decreased according to increase in the number of days for wet curing at early age. Gas diffusion coefficient was inversely proportional to cement hydrate content. From these results, as similarly to a case of ordinary cement mortar, it has been proved that wet curing at early age is also important for polymer cement mortar.ポリマーセメントモルタルは、ポリマーフィルムの形成により緻密性に優れ、建物の補修などに使用されている。しかし、施工上十分な養生を行うことが困難な場合も多い。そこで本研究は、温度20℃、相対湿度60％の環境下におけるポリマーセメントモルタルの気体拡散係数へのポリマー量やセメントの水和の影響を明らかにすることを目的に、実験検討を行った。その結果、本研究のポリマー量0～60kg/m³において、ポリマー量が0から20kg/m³まで増加しても気体拡散係数はほとんど変化しないものの、それ以上増加すると比例して減少した。また、材齢初期の湿潤養生期間が長くなるほどセメントの水和は進行し、気体拡散係数は小さくなることが明らかとなった。

Series of tests were carried out on reinforced concrete knee joints with/ without upper column stub to validate the anchor details of beam rebars and the stub size suggested in AIJ Standard of RC. The column stub was effective on the anchorage strength and the strut mechanism in case of larger than the half of the beam depth as recommended in the Standard, while it was not effective in case of the smaller stub. The 180 degree hooks only at the four corner of the stub top were effective, though the splitting failure could be induced due to the stress concentration.

Experiments were carried out to examine the anchorage of column rebars for RC buildings with pilotis floor where the column depth greatly reduces. All the specimens failed in raking-out before the flexural yielding. It is important to avoid greatly reducing the column depth. When it is unavoidable to reduce the column depth; to transfer the column stresses to other members surely, note that: (1) the depth of beam over the pilotis floor should be as large as the column rebars are developable, (2) the beam bottom should be reinforced longitudinally enough.