Kebutuhan material dalam konstruksi beton semakin meningkat namun persediaan material agregat halus, pasir sungai mulai mengecil sehingga perlu memikirkan alternatif penggunaan pasir pantai untuk pengerjaan konstruksi beton. Penelitian  bertujuan untuk mengetahui karakteristik material dan kuat tekan beton. Jumlah benda uji masing-masing 15 buah slinder untuk beton yang menggunakan material dicuci dan tidak dicuci. Perawatan beton dilakukan perendaman umur 3 hari, 7 hari, 28 hari. Hasil pengujian karakteristik agregat halus dari Desa Wolowa Baru Kecamatan Wolowa, kadar lumpur pasir 1,96 %, kadar air pasir 1,40 %, berat volume pasir kondisi lepas 1,40 dan kondisi padat 1,60, berat jenis pasir nyata 3,40, berat jenis pasir dasar kering 2,83, berat jenis pasir kering permukaan 2,90, modulus kehalusan 2,53 serta absorpsi 2,42. Kadar lumpur kerikil 0,19 %, kadar air kerikil 0.73%, berat volume kerikil kondisi lepas 1,42, berat volume kondisi padat 1,60, absorpsi 1,44 %, berat jenis nyata kerikil 1,94, berat jenis kerikil dasar kering 1,89, berat jenis kerikil kering permukaan 1,92 dan modulus kekasaran 8,86. Pada umur 3 hari kuat tekan beton material tidak dicuci sebesar 8,34 Mpa, 7 hari sebesar 12,71 Mpa, dan 28 hari sebesar 18,38 Mpa dan kuat tekan beton material dicuci pada umur 3 hari sebesar 10,19 Mpa, 7 hari sebesar 13,25 Mpa, dan umur 28 hari 19,43 Mpa. Hasil kuat tekan beton 28 hari menunjukan beton menggunakan material tidak dicuci lebih rendah dari beton menggunakan material dicuci. Peningkatan kuat tekan material dicuci sebesar 5,71 % terhadap nilai kuat tekan beton material tidak dicuci.

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<p>The Wave Catcher Shore Protection Dual-Slope (WCSP-DS) model in this study is a model of a dual function beach building as a beach protector and a catcher of wave energy, which has two walls, namely upright and inclined walls with an angle of 45°. The WCSP-DS building also has a reservoir at its top to accommodate wave runoff (overtopping). This study aims to determine the reflection in front of the model with variations in the freeboard height of the Wave Catcher Shore Protection Dual-Slope (WCPS-DS) building in a zigzag position. The test was carried out using a 1:20 scale 3D physical model at the Coastal and Environmental Engineering Laboratory, Faculty of Engineering, Hasanuddin University, Makassar. Simulation and data acquisition were carried out in a wave basin measuring 15 meters long, 10 meters wide using a regular wave generation system and the wave height data on the wave probe was recorded automatically. The simulation was carried out with 5 variations of freeboard height on 3 variations of waves, namely wave height and period and 3 variations of water depth. The results showed that there was a significant effect of freeboard height, wave steepness and water level position on WCSP-DS vertical wall height or water depth relative to the wave reflection coefficient in front of the model. The value of the reflection coefficient (Kr) in the relationship between freeboard height and water depth (Fb/d) at a depth of 0.4 meters (d/z = 1.143) ranges from 0.42 – 0.74, at a depth of 0.35 meters (d /z = 1) ranged from 0.44 – 0.74 and at a depth of 0.3 meters (d/z = 0.857) ranged from 0.35 – 0.71.</p>