CIVIL ENGINEERING, SCIENCE AND TECHNOLOGY CHALLENGES : STRUCTURAL ENGINEERING AND CONSTRUCTION MATERIALS

The book is based on scientific and technological advances in various Structural Engineering and Construction Materials areas of Civil Engineering. It nurtures therefore the exchange of discoveries among research workforces worldwide including those focusing on the vast variety of facets of the fundamentals and applications within the Structural Engineering and Construction Materials arena. To offer novel and rapid developments, this book contains original contributions covering theoretical, physical experimental, and/or field works that incite and promote new understandings while elevating advancement in the Structural Engineering and Construction Materials fields. Works in closing the gap between the theories and applications, which are beneficial to both academicians and practicing engineers, are mainly of interest to this book that paves the intellectual route to navigate new areas and frontiers of scholarly studies in Structural Engineering and Construction Materials

MODIFIED CEMENT SYSTEM: DURABILITY AND AESTHETICS

Concrete deterioration is one of the most concerning matters in the construction world. Significant decay such as efflorescence should not be ignored. The efflorescence is a deposit of salts, usually white, formed on the surface of the concrete. The efflorescence is not a significant problem that leads to structural defects, but it can build unattractiveness to the structure, such as brick walls and concrete mortar. The way to prevent the efflorescence occurrence is by studying the results of testing such as absorption and efflorescence itself to reduce the efflorescence. The non-modified cement system can reduce efflorescence but cannot avoid it because of the reaction of cement hydration itself. This study proves that using a modified cement system such as Pulverized Fly Ash (PFA) and Polymers (water-based latex grade 29Y46), the efflorescence of the mortar can be prevented. This study proved that the modified mortar, a sample with PFA and Polymers, has higher strength, durability, and minor efflorescence than the non-modified cement system

MODIFIED CEMENT SYSTEM : DURABILITY AND AESTHETICS

Concrete deterioration is one of the most concerning matters in the construction world. Significant decay such as efflorescence should not be ignored. The efflorescence is a deposit of salts, usually white, formed on the surface of the concrete. The efflorescence is not a significant problem that leads to structural defects, but it can build unattractiveness to the structure, such as brick walls and concrete mortar. The way to prevent the efflorescence occurrence is by studying the results of testing such as absorption and efflorescence itself to reduce the efflorescence. The non-modified cement system can reduce efflorescence but cannot avoid it because of the reaction of cement hydration itself. This study proves that using a modified cement system such as Pulverized Fly Ash (PFA) and Polymers (water-based latex grade 29Y46), the efflorescence of the mortar can be prevented. This study proved that the modified mortar, a sample with PFA and Polymers, has higher strength, durability, and minor efflorescence than the non-modified cement system

Laboratory study of water absorption of modified mortar

This study investigates the effects of polymer additives namely polyvinyl acetate (PVAc) on water absorption and compressive strength of mortar. Twelve mortar mixtures were investigated for water absorption test and compressive strength test. Results showed that water absorption were inversely proportional to the percentage of PVAc addition. Final analysis showed that addition of PVAc had significant effects on water absorption. Samples with 1%, 3% and 5% addition of PVAc showed an increase of water absorption capacity in comparison to control mortar

Effect of PFA on strength and water absorption of mortar.

Partial replacement of cement by mineral admixtures or pozzolans can possibly improve the durability of mortar which directly related to its water absorption. Pulverized Fuel Ash (PFA) is one of the pozzolans that is locally available. Laboratory studies have been conducted on mortar mixes of 0.3w/c, 0.4w/c and 0.5w/c ratios with 10%, 20% and 30% PFA replacements. Mortar cubes were tested to determine their water absorption rates and compressive strengths as they mature. Amount of PFA replacements in the mortar has significant effects on the strength development and water absorption rate of the mortar. Results shows that 20% PFA mortars of 0.5w/c ratio is the best mix to reduced rate of water absorption and achieved higher compressive strength

Laboratory study of water absorption of modified mortar.

This study investigates the effects of polymer additives namely polyvinyl acetate (PVAc) on water absorption and compressive strength of mortar. Twelve mortar mixtures were investigated for water absorption test and compressive strength test. Results showed that water absorption were inversely proportional to the percentage of PVAc addition. Final analysis showed that addition of PVAc had significant effects on water absorption. Samples with 1%, 3% and 5% addition of PVAc showed an increase of water absorption capacity in comparison to control mortar

Effect of PFA on strength and water absorption of mortar

Partial replacement of cement by mineral admixtures or pozzolans can possibly improve the durability of mortar which directly related to its water absorption. Pulverized Fuel Ash (PFA) is one of the pozzolans that is locally available. Laboratory studies have been conducted on mortar mixes of 0.3w/c, 0.4w/c and 0.5w/c ratios with 10%, 20% and 30% PFA replacements. Mortar cubes were tested to determine their water absorption rates and compressive strengths as they mature. Amount of PFA replacements in the mortar has significant effects on the strength development and water absorption rate of the mortar. Results shows that 20% PFA mortars of 0.5w/c ratio is the best mix to reduced rate of water absorption and achieved higher compressive strength

INITIAL SURFACE ABSORPTION OF POZZOLAN AND POLYMER MODIFIED MORTAR

This study involves the investigation of water absoption of mortar modified with combinations of polymer and pozzolan by using initial surface water absorption test (ISAT). Since surface of mortar or concrete serves as medium that will be most easily penetrated by moisture that can cause corrosion of reinforcement bars that leads to durability problem, it is imperative to make it durable.Polymer additive and pozzolanic cement replacement used in this study was Styrene Butadiene Rubber (SBR) and Fly Ash (FA) respectively. Mixes were prepared with two water to cement ratios (w/c) of 0.3 and 0.4 with different combinations of 5%, 7% & 10% SBR additive and 10%, 20% and 30% FA cement replacement. Results showed that modified mortar with combination of higher percentages of polymer additive and lower percentages of pozzolonic cement replacement have the lowest initial surface absorption rate compare to unmodified mortar. It can be concluded based on this study that high percentage of polymer addition and low percentage of pozzolanic cement replacement in mortar can enhance its resistance to water absorption