Pile bearing capacity of the new bridge over Zambezi River (Mozambique): predictions and performance of static load test results

Abstract

The evaluation of pile bearing capacity is dependent on the interpretation of the pilehead load-settlement curve and the determination of the shaft and toe resistances in careful andwell instrumented tests. It is then possible to calibrate design methods with load transfer curves atdifferent depths for progressive loading levels. In the New Zambezi Bridge (Caia Chimuara,Mozambique) deep foundations have been designed taking into consideration differentmethodologies: methods based directly in SPT data (Reese & ONeill) and methods based in CPTdata (Bustamante & Frank, 1999), giving rise to some scatter in final results. For the complete andtrustful solution, static load tests on some piles were executed using the Osterberg test method, inorder to obtain a simple way to evaluate shaft load transfer and define the applicability of eachempirical methodology. Results of this comparative analysis are proposed and some suggestionsare presented for regional practice.