Abstract:
ABSTRACT
Over time, cases of collapsing buildings have increased. Mavoko water from Ukambani region of Kenya is
prone to a combination of several salts attributed to decreasing concrete stability. This study aimed at analyzing
the extent by which this water affects concrete compressive strength, soundness and setting time. Ordinary
Cement (OPC) and Pozzolanic Portland Cement (PPC) containing 20% filler (PPC-1) and 30% filler (PPC-2)
were moulded using different water samples and their setting time, strength and soundness monitored. The
results proved Mavoko water retarded concrete compressive strengths, increased soundness and fluctuated
setting times. Concrete expansion increased by 2.5mm. This water had large margins of up to 54±2 minutes
between early and late setting times recorded. The water gave retarded values for both early (30.51MPa) and
late (40.12MPa) compressive strengths. Concrete containing Mavoko water gave outlier late compressive
strengths for both cement brands (p ≤ 0.05, n= 14). This study highlighted the need for stricter regulations to
be put on this water used in major constructions.
Key words: Concrete, Mavoko water, soundness, setting-time, concrete strength
