CHAPTER Il, SECTION 1B In conjunction with the above tests, additional tests and surveys were made on coral concretes in regard to: (1) effect of temperature on curing rate; (2) effect of use of salt water in mixes: (3) use of admixtures; (4) methods of processing, including membranes; (5) study of variations of water content; (6) study of shear patterns. Placement of concrete was required cn 25 different isiand sites in the two atolls. Seven stockpiles and seven central concrete batch pla. *s were established. Figure 2-23 shews the start uc a typical stockpile. The fine aggregate pile . in the right foreground; the coarse aggregate is in the background. With the placement cf concrete, compressive strength cylinders were made and shipped to the laboratory at Elmer. A total of 800 cvlingers were tested for quality. This amounted to one control cvlinder tested for every 32 cubic yards of concrete poured during the Operation. A breakdown of the results obtained from tes.ing these 200 quality-control cylinders from all classes of conerete is tabulated as follows: Class of Concrete Averages at 28 days Eniwetok Bikin: 2000 2590 3609 3300 24593 2808 3943 3690 psi psi psi pst sites required required required required sites psi psi psi pai 2546 34563 3612 3866 psi psi psi psi The laborator, provided a variety of testing services other than mix design and quality control on concrete and concrete aggregates, An Figure 2-22. extensive senes of soil plate bearing tests were Tn me -. . Lee : ee hoe oe eee, lng : “ewer a ia pr. -_ oo Twenty-eight Day Concrete Test Cylinder ee a ta . ra ver: ™. aes eo "Fr + a!* ¢n- ousgreen . - _™ *, -_ om oa “7 ~ : «tf Figure 2-23. tol a~ : Ly * * . -. ~\ . : ee coe Crusher Plant at Site Charlie Page 2-48 OF Seaneee” cemr * Tere nae ee ee ee Sa a ett nae ae ee ee rane cama - : “ oeee ee acd celeTie ls ade Sa © Aatlldill oi Ser ada A me Oct mt atirMela anand is