ABSTRACT
A b s t r a c t In the past years, extensive research has been c a r r i e d out at the I n s t i t u t e of B u i l d i n g M a t e r i a l s and M a t e r i a l s T e s t i n g a t the U n i v e r s i t y of Hanover i n the f i e l d of f r e s h concrete technology. One of the aims of t h i s work was to describe the connections between the v a r y i n g consistency behaviour of concretes produced i n ready mixed p l a n t s and l a b o r a t o r i e s •
The t e s t r e s u l t s showed that i n i t i a l c o n s i s t e n c i e s of pl a n t and laboratory t e s t s b u i l d a good c o r r e l a t i o n , i f the comparable po i n t of time i s defined e x a c t l y , and i f the act u a l water content i s taken i n t o c o n s i d e r a t i o n . Apparently higher s t i f f e n i n g of f r e s h concrete i n the la b o r a t o r y t e s t can be r e l a t e d to the app l i e d t e s t i n g procedure. Keywords ; Fresh Concrete, Consistency, S t i f f e n i n g , Ready Mixed Concrete, Laboratory Concrete
1 Introduction
One of the important tasks i n the production and the d e l i - very of ready mixed concrete i s to ensure t h a t , a t the time of s i t e d e l i v e r y , the required consistency should be achieved under any c o n d i t i o n . The s o l u t i o n of t h i s task presupposes t h a t the in f l u e n c e s on the i n i t i a l consistency and the s t i f f e n i n g are known. Among other things these i n f l u e n - ces are the concrete c o n s t i t u e n t s , the concrete composit i o n , the concrete mixing, the concrete temperature and time.
