In the years preceding the 1979 national elections, ideology featured prominently in political debates and consultations regarding the new constitutional order. Proponents of a social democratic system were particularly prominent. However, the actual formation of political parties, governed by the new requirements for national representation, and the resurgence of veteran...
A half-century of high revenues from petroleum export has failed to elevate more than a small percentage of Nigerians above the poverty level. The failure to manage the vicissitudes of global oil markets, and to grow other sectors of the economy, has led to constant budget deficits and unsustainable national...
The issues discussed in this essay - the fundamental objectives of the Nigerian state, public accountability, and a code of conduct for state officials - have been central concerns throughout its post- colonial history. Underlying these debates have been differing views about the best political economy model for Nigeria. The...
The gradual evolution of the material properties of a cement-based material, i.e. the stiffness of cement paste, is the result of the continuous change of the microstructure with the progress of the hydration process. Based on an existing micromechanical model for the simulation of the shear and elastic modulus of...
In this paper, the correlation of reflection loss measured by an ultrasonic shear wave reflection
method and the microstructure in cement-based material is investigated. Three cement pastes
(Portland cement type I) with different water-cement ratios (0.35, 0.50 and 0.60) cured at 25
°C were examined. The ultrasonic shear wave reflection...
The paper deals with the behavior of fluid cement pastes, formulated from Self Consolidating Concretes (SCCs), and the experimental correlation of fundamental rheological properties, such as the yield stress and the viscosity, with measurements from field tests, such as the mini-cone slump flow test. As a matter of fact, several...
An empirical procedure for fitting a complementary error function (erfc) to settlement and lateral ground movement data in a direction parallel to an excavation support wall is proposed based on extensive optical survey data obtained around a 12.8 m excavation in Chicago. The maximum ground movement and the height and...
Several three-dimensional effects were observed in the performance monitoring data collected during excavation for the Ford Engineering Design Center (FEDC) in Evanston, Illinois. These responses are related to lateral deformations of the soil around the excavation walls, forces in the cross-lot and diagonal bracing that supported the temporary wall and...
This paper presents the results of 159 finite element simulations conducted to define the effects of excavation geometry, i.e., length, width and depth of excavation, wall system stiffness, and factor of safety against basal heave on the 3-dimensional ground movements caused by excavation through clays. The results of the analyses...