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The driven pile designs in intermediate geomaterials (IGMs) entail relatively significant levels of uncertainty because of the transitional properties of IGMs between soil and hard rock. The performance and acceptability of driven piles in IGMs are typically evaluated using dynamic load test (DLT) approaches. Even though dynamic techniques have significant technological and financial advantages, a static pile load test (SLT) is required to comprehend the static behavior of driven piles in IGMs. This study presents three distinct SLT systems (independent, integrated, and innovative) that are performed on steel H-piles driven in IGMs in Iowa, Wyoming, and Colorado, respectively. Test pile 2 (TP2) is driven into siltstone in Wyoming, whereas test pile 1 (TP1) and test pile 3 (TP3) are driven into shale in Iowa and Colorado, respectively. DLTs are conducted using Wave Equation Analysis Program (WEAP) and Pile Driving Analyzer (PDA) with a signal-matching analysis utilizing the Case Pile Wave Analysis Program (CAPWAP). The ultimate pile resistances are evaluated using six distinct failure criteria. According to the Davisson criterion, TP1 has the ultimate pile resistance of 305 kips, which is 11% and 2% less than the CAPWAP and WEAP analyses, respectively. For TP2, ultimate pile resistances based on all SLT criteria are higher than that from the DLTs, except for the 5%B criterion with ultimate pile resistance at 7% lower than CAPWAP. It is evident from TP3 that the ultimate resistances acquired from SLTs are higher than the resistances obtained from dynamic analysis.

In the present work, we investigate how pressure affects the valence change of cerium in cerium-based compounds CeX (X= O, S, Te, P, As, Sb, and Bi). The valence of cerium at a certain high pressure is estimated by comparing the experimentally observed unit cell volume and the calculated unit cell volume of stable trivalent cerium ion in the compound. The change in unit cell volume with pressure is estimated by employing the Birch equation of state. It is found that the valence of Ce in the CeX is significantly influenced by both the applied pressure as well as the chemical environment around the Ce ion. J. Bangladesh Acad. Sci. 46(2); 147-154: December 2022

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