CIVENG 3P04 Chapter : 3P notes.docx

• School: McMaster University
• Department: Civil Engineering
• Course: CIVENG 3P04
• Professor: T A

Document Summary

Ch1 less water: +strength, permeability, +resistance to weathering, better nodding, shrinking/cracking. Workability: method of transport, quantity and charactaristics of materials, slump, grading, shape, texture of aggregate, air content, water content, air temperature, admixtures. Bleeding: layer of water ontop of the fresh concrete due to settlement of solids, some bleeding is okay, causes settlement shrinkage, caused by. Well graded aggregate (less cement paste required) Durable: done by vibrating the concrete. 90% of portland cement is made of: tri calcium silicate, dicalcium silicate, tricalcium aluminate, tetracalcium aluminoferrite. Calcium silicates: 75% of cement, react with water to make. Setting hardening strength and stability depend on this. Contains lime (cao) and silicate (sio2) 3 to 2 ratio: as concrete hardens these compounds give the strength, weakness is in voids filled with water and air. Heat of hydration can protect the concrete during the winter, but can also cause temperature differentials in larger structures (thermal cracking)