https://doi.org/10.1007/978-981-15-0802-8_130 Experimental Correlations for the Swelling Pressure of Expansive Clays in the City of Tebessa, Algeria Adel Djellali 1 , Behrooz Saghafi 2 , Mohamed Salah Laouar 3 1 Mining institute, Larbi Tebessi University, 12002 Tebessa, Algeria. E-mail: adel.djellali@univ-tebessa.dz 2 Highway Engineer and Highways Innov8 Champion, Capita Real Estate and Infrastructure, UK. Email: behrooz.saghafi@capita.co.uk 3 Civil Engineering Department, Larbi Tebessi University, 12002 Tebessa, Algeria. E-mail: medsalah.laouar@univ-tebessa.dz Abstract. This paper aims to describe the dependency of the swelling pressure (Ps) of Tebessa clay soils to the conventional soil properties namely; Plasticity index (PI), dry density ( d ), initial moisture content (W) and carbonate content (Ca). A statistical model, capable of obtain- ing an indirect estimation of Ps based on these soil parameters, is provided. High correlation coefficient (R 2 ) of 0.93 demonstrated predictability of swelling, using multiple regression mod- eling. Although the above-mentioned parameters play important roles in the swelling behavior of the clayey soils, there is not any universally accepted, simple and quantitative method to classify swelling pressure at present. The equation, proposed in this paper, helps the engineers with evaluating soil pressure in practice. In addition, it can be popularized when environment conditions are satisfied for application in field explorations and design of structures over ex- pansive soils. Keywords: Expansive Clays, Swelling pressure, geotechnical parameters, regression analysis. 1. Introduction The soils of Tebessa city in Algeria, North of Africa, are mainly composed by layers of limestone, gravels and calcareous tufa. However, the middle part of the city pre- sents extensive clay layers and marly clays with swelling behavior [1]. In this part of city, the overall types of construction are essentially residential housing and flexible pavements, that have suffered with cracking and premature loss of serviceability, caused essentially by the swelling behavior of underlying clays. Swelling of clays affects the structural stability of the overlying infrastructure due to volume change associated with seasonal moisture content fluctuation in the underlying soils [2]. Var- ious remedial measures like soil replacement [3], pre-wetting [4], moisture control [5] and lime stabilization [6] have been practiced with varying degree of success. How- ever, these techniques have a certain limitations regarding their adaptability matters. Rational design of foundations of constructed facilities and pavements structure re- quires prediction of the swelling characteristics of clays. If soil is suspected to be expansive during preliminary site investigation, the swelling parameters are estimated using the correlations available in literature. The empirical expressions relate the © Springer Nature Singapore Pte Ltd. 2020 C. Ha-Minh et al. (eds.), CIGOS 2019, Innovation for Sustainable Infrastructure, Lecture Notes in Civil Engineering 54, 817