하늘땅

 Precast pretensioned voided slabs 중공 프리캐스트 빔 252-New-standard-precast-concrete-bridge-beams-stage-1-identification-of-new-standard-beam-shapes 8.3.5 Transverse Design Preliminary design indicates that increasing the transverse prestress, providing continuous ducts, and increasing the depth of the grouted joints between units are likely to provide the most cost-effective solution for the hollow core deck units. On the other hand the provision of an overlay slab will increase the cost of construction because of a reduction in structural efficiency for the deck units and an increase in site construction work. 예비 설계에 따르면 횡방향 프리스트레스를 높이고, 연속 덕트를 제공하며, 유닛 사이의 그라우트 조인트 깊이를 늘리는 것이 중공 코어 데크 유닛에 가장 비용 효율적인 솔루션을 제공할 수 있는 것으로 나타났습니다. 반면에 오버레이 슬래브를 제공하면 데크 유닛의 구조 효율성이 감소하고 현장 시공 작업이 증가하기 때문에 공사 비용이 증가합니다. 8.3.6 Longitudinal Joints Between Units  The existing detail for the joint between hollow core deck units provides a grouted joint with a profiled shear key formed in the sides of the ab...

Young concrete 토목구조기술사 면접시험에 나왔다고 하길래 GPT에 물어보니 다음과 같이 답변을 해줬다. Young concrete refers to freshly mixed concrete that has not yet hardened or reached its final strength. This stage is critical in concrete construction because the properties of young concrete can significantly influence the long-term durability and strength of the structure. Here are some key aspects of young concrete: Properties Workability : Young concrete must be workable enough to be properly placed and compacted. The workability is influenced by the water-cement ratio, aggregate size, and the use of admixtures. Setting Time : This is the time it takes for the concrete to begin hardening. Setting time can be adjusted by using different types of cement and admixtures. Bleeding : The process where water rises to the surface of freshly placed concrete. Excessive bleeding can weaken the surface layer and affect the durability. Heat of Hydration : The chemical reaction between cement and water releases heat. In young conc...

 Figure D.1 Types of anchors (See Clauses D.1.2, D.2, and D.3.)