5. Conclusions

The relationship between UPV, fc (compressive strength), and dry density for the mix proportions in Table 8 is presented in Figures 8 and 9. It can be observed that for the LWC in this study, as the dry density increases, UPV and fc also increase, but the results are scattered when working with LWC. To be able to compare these results from those of NWC, mixes of NWC with similar compositions but without any LWA were produced, and results were presented in

Figures 10 and 11. It is observed that the result for the relationship between UPV, fc and, dry density for LWC is more scattered than similar test result for NWC.

Figure 8.

Figure 9.

Figure 10.

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UPV versus dry density for LWC.

fc versus dry density for NWCUPV versus dry density for NWC.

fc versus dry density for LWC.

Compressive Strength of Concrete

There are different types of LWC available in the industry that depending on the method which is used for production of each type, the properties of the LWC can be completely different. Lightweight aggregate concrete (LWAC), foamed concrete (FC), and autoclaved aerated concrete (AAC) are among the most common types. On the other hand, structural and nonstructural lightweight concrete can be produced for different purposes. Lightweight aggregate concrete, such as the one discussed in this study, are being used nowadays in the advancement of concrete technology, but it is proven that each type of LWA needs to be tested before being used in structures and even for nonstructural purposes. Compressive strength of LWC is an important characteristic of LWC that can be measured or predicted with few methods such as NDT methods. Ultrasonic pulse velocity was utilized to assess the compressive strength, fc, of the LWC containing EGA in the present study. In this chapter it was observed that LWA can replace NWA to achieve smaller bulk densities and UPV can be used as a method for evaluation of compressive strength of LWC. Based on the case study conducted in the present chapter, it was showcased that as the dry density of the LWC decreased, UPV and fc decreased, respectively. Comparisons of actual fc values obtained from CTM proved UPV can be related to fc, and the results showed similar characteristics to previous works, while the previous work's equations cannot be used for the aggregates used in this study. The results of the present study are limited to the mix design and materials that were used in this work, and it should be noted that these results cannot be extended to other types, sizes, etc. of aggregates and different mix designs.

Compressive Strength of Concrete
