AbstractPervious concrete contains a connected network of pores that allows water to pass through the material and can help limit surface runoff. This porosity, however, may also affect its load-bearing capacity. This work examined how nylon-fiber length influences compressive strength, splitting tensile strength, and measured void content when the fiber dosage is held constant. The laboratory program comprised 36 cylindrical specimens (150 mm × 300 mm) representing a plain mixture and mixtures reinforced with nylon fibers 20, 30, or 50 mm long. Fiber dosage was 0.9 kg/m³, and testing was performed at 28 days. Mean compressive strength was 19.43 MPa for the control, compared with 19.21, 18.89, and 18.65 MPa for the 20, 30, and 50 mm mixtures, respectively. These values represent reductions of 1.13%, 2.78%, and approximately 4.01%. Splitting tensile strength did not follow a monotonic trend: the respective means were 1.748, 1.746, 1.775, and 1.675 MPa. The 30 mm mixture had the largest measured mean, 1.775 MPa, around 1.54% above the control. Measured void content was 26.16% for the control and 26.32%, 37.89%, and 27.39% for the reinforced mixtures. Thus, fiber length was associated with different responses across the properties measured under the conditions of this experiment.Keywords: Compressive strength; Fiber length; Nylon fiber; Pervious concrete; Void content. AbstrakBeton lolos air memiliki jaringan rongga yang saling terhubung sehingga air dapat meresap melewati material dan limpasan permukaan berpotensi dikurangi. Di sisi lain, tingkat porositas tersebut dapat memengaruhi kemampuan beton menahan beban. Penelitian ini mengevaluasi pengaruh panjang serat nilon terhadap kuat tekan, kuat tarik belah, dan kandungan rongga terukur ketika kadar serat dipertahankan tetap. Pengujian laboratorium melibatkan 36 benda uji silinder berukuran 150 mm × 300 mm, yang mewakili campuran kontrol tanpa serat serta campuran dengan serat nilon sepanjang 20, 30, dan 50 mm. Dosis serat ditetapkan sebesar 0,9 kg/m³ dan pengujian dilakukan pada umur 28 hari. Kuat tekan rata-rata campuran kontrol sebesar 19,43 MPa, sedangkan campuran serat 20, 30, dan 50 mm masing-masing mencapai 19,21, 18,89, dan 18,65 MPa. Nilai tersebut menunjukkan penurunan sebesar 1,13%, 2,78%, dan sekitar 4,01%. Kuat tarik belah tidak menunjukkan pola kenaikan atau penurunan yang berurutan; nilai rata-ratanya berturut-turut adalah 1,748, 1,746, 1,775, dan 1,675 MPa. Campuran serat 30 mm menghasilkan nilai rata-rata terukur tertinggi, yakni 1,775 MPa atau sekitar 1,54% di atas kontrol. Kandungan rongga terukur pada campuran kontrol adalah 26,16%, sementara campuran 20, 30, dan 50 mm masing-masing menghasilkan 26,32%, 37,89%, dan 27,39%. Dengan demikian, panjang serat berkaitan dengan respons yang berbeda pada setiap parameter yang diuji dalam batas kondisi eksperimen ini.Kata Kunci:Beton berpori; kandungan rongga; kuat tekan; panjang serat; serat nilon.