Study on the chemical prestressed shin panel with high expansive concrete

从施工的安全性、快速性、无噪音性以及建筑中的环境措施、地球尺度上的森林环境保护等方面考虑，用永久形式代替木形式和支撑物的施工方法已经开始推广。永久形式使用的形式就像混凝土的主体一样，与木材形式相比，它具有很高的抗应力，并且使得施工工作在浇筑后不需要将形式与混凝土分离。当用混凝土制作永久形式时，从防止自缩和干缩引起的裂缝或减轻构件截面重量的角度来看，引入预应力是可取的。就其目的而言，引入均匀预应力变得重要，以免引起挠曲，使用碳纤维网，即使是薄覆盖也不会生锈。PC面板采用2向预应力制作，大量CFRP筋必须采用特殊的预张法固定。为了使用这种张拉设备，必须进行先进的张拉管理，本研究探讨了不需要CFRP筋固定设备的化学预应力混凝土（CPC）的应用。当使用低弹性系数的预应力时，为了使有效预应力大，碳纤维布预应力的张拉应超过JSCE混凝土规范规定的应变700 μ。从材料组成、膨胀机理、膨胀压力、配合比、养护方式、约束程度、聚合物掺合等方面对CPC在高膨胀条件下的预应力引入特性进行了耐久性改善试验研究。

The method of construction which uses the permanent form instead of an wood form and supports have begun to spread from the viewpoint of construction's safety, the quickness, making noiseless, and the environment measure in building, the forest environment protection at the earth scale and so on.The permanent form which uses a form just as it is as the body of concrete has high proof stress compared with the wood form, and makes the construction work possible without separation of the form from the concrete after casting.When making an permanent form from concrete, it is desirable to introduce a prestress from the viewpoint of the crack prevention due to the self shrinkage and the dry shrinkage or the reduction of weight of the member's cross section.For its purpose, the introduction of uniform prestress becomes important so as not to causes a deflection, using the carbon fiber meshes which is not rust even if it is thin cover.Making the PC panel by 2 directions prestress, a lot of CFRP tendons must be fixed by special pre tensioning method. To use such tensioning equipment, the advanced tensioning management became necessary, it examined the application of chemical prestressed concrete (CPC) which doesn't need the fixing equipment of the CFRP tendon in this study.When using a tendons with low elasticity coefficient, to make an effective pre stress big, it is necessary to tense in the CFRP tendons beyond 700 μ of strain which is prescribed with the concrete specification of JSCE.It examined experimentally from the aspect of durable-ness improvement by the material composition, the expansion mechanism, the expansion pressure, the mix proportion, the curing method, the degree of the restriction, and the polymer mixing about the pre stress introduction characteristic by CPC under such high expansion.