At any stage of hydration, the hardened paste consists of:
1. crystallized hydrates of the various compounds (calcium silicates hydrate, tricalcium aluminates hydrate and calcium ferrite) , referred to collectively as gel.
2. Crystals of Ca(OH)2 produced from the hydration of the silicates.
3. Some minor components.
4. unhydrated cement.
5. Voids Capillary pores
Gel pores
a- Capillary pores: the capillary pores at any stage of hydration represent that part of the gross volume which has not been filled by the products of hydration. The volume of the capillary system is reduced with the progress of hydration.
Gel pores: The gel pores are interconnected interstitial spaces between the gel particles. The gel pores are much smaller than the capillary pores. It could be contain large amount of evaporable water.
Water held in hydrated cement paste
We can see that water in hydrated cement is held with varying degrees of firmness and can be classified as:
1. Free water: present in the capillary pores – with weak firmness, and evaporate quickly leaving the paste.
2. Chemically combined water: form a definite part of the hydrated compounds.
3. Gel water: which found
a) Gel pores
b) Part of it is held by the surface force of the gel particles
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
الرجوع الى لوحة التحكم
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