Module 1 - Precast Concrete PDF

ARB 426 BUILDING TECHNOLOGY 5: ALTERNATIVE BUILDING CONSTRUCTION SYSTEMS Ar. Jaerica Mae S. Espeleta, uap, RMP Registered and Licensed Architect and Master Plumber OUTLINE: 1.What is a precast concrete? 2.What are the components of a precast concrete system? 3.What are the considerations...

ARB 426 BUILDING TECHNOLOGY 5: ALTERNATIVE BUILDING CONSTRUCTION SYSTEMS Ar. Jaerica Mae S. Espeleta, uap, RMP Registered and Licensed Architect and Master Plumber OUTLINE: 1.What is a precast concrete? 2.What are the components of a precast concrete system? 3.What are the considerations when using a precast concrete system? 4.What are the comparisons between cast in place concrete and precast concrete? WHAT IS A PRECAST CONCRETE? Precast concrete is a construction material created by pouring concrete into a pre-shaped mold. The concrete is then left to cure in an appropriate environment. Once cured, the mold is removed and reused. The precast concrete product is then taken to the job site and used for the project TYPICAL USES OF PRECAST CONCRETE Walls, Floors, Beams, Columns, Stairs, and Modules CAST IN PLACE CONCRETE VS. PRE CAST CONCRETE CAST IN PLACE PRECAST Waiting time is longer because labor and space is required to be ready Casting Ready for immediate placement on a construction site. for on-site casting. Better quality due to controlled environment of production i.e. Water Quality Control More susceptible to compromised quality due to workmanship error Cement Ratio Labor Efficiency Involves manual work that increases labor costs and overheads. Less need for skilled labor and easy assembly leading to lower manhours Speed Time consuming process waiting time for concrete strength (28 days) Less time on site no waiting for full strength less false/form works of Construction CAST IN PLACE CONCRETE VS. PRE CAST CONCRETE CAST IN PLACE PRECAST Concrete needs another 7 days before a concrete member can be Curing conditions for precast concrete are factory-controlled. Workers Curing Conditions placed or connected to the previous one. can speed them up while maintaining the product’s strength and quality. Rain does not disrupt the installation of precast members on site and Weather Conditions An unexpected rainstorm can grind on-site casting work to a halt. the contractor can still lift them into place. Economy Higher Cost and Material waste Lower Cost (specially in labor and raw materials) Formworks Good for customized structural element Good for repetitive structural elements CAST IN PLACE CONCRETE VS. PRE CAST CONCRETE CAST IN PLACE PRECAST Handling Less use of heavy equipment Reliance on heavy equipment and machineries Joints are very critical component of the system and need utmost Joints Less joints and most of the system is monolithic attention in design Earthquake Resilience Resilient Resilient Contractor Generic Specialized CAST IN PLACE CONCRETE VS. PRE CAST CONCRETE CAST IN PLACE PRECAST Environmental Impact Higher negative impact due to generated construction waste Lesser impact (some can be reused and easily disassembled) less waste Plastering Needs to be finished with plastering Less plastering requirements due to better molding conditions CHARTER ARTS SCHOOL | BETHLEHEM, PA HERSHEY MEDICAL CENTER | HERSHEY, PA WHEN DO WE USUALLY USE PRECAST SYSTEM? Projects with repetitive elements Big projects that requires with longer span Ideal site and logistics conditions because precast become relatively cheaper than cast in place CAST IN PLACE IS USUALLY USED FOR: Structures with high variability Smaller projects Sites with limited access or logistics problems  THANK YOU Ar. Jaerica Mae S. Espeleta, uap, RMP Registered and Licensed Architect and Master Plumber