The assessment of a soil’s liquefaction potential can often have major financial implication for infrastructure projects. An overly conservative assessment can lead to unnecessary expenditure on foundations or ground improvement. The assessment of liquefaction potential in recent deposits of alluvial soils with grains of lithic…
This paper presents a simplified procedure for predicting earthquake-induced level and sloped ground failure, namely liquefaction and shear failure. It consists of a framework where cyclic stress ratio (CSR), static stress ratio (SSR) and undrained shear strength (USS) are formulated considering simple shear conditions, which…
Predicting the severity of liquefaction induced ground damage is the key outcome from a liquefaction assessment. Ishihara (1985) developed a simple and logical method to predict the occurrence of sand boils, ground fissures and other features of liquefaction damage. This paper examines the effectiveness of…
The damage to Christchurch’s lifelines has been observed widely across the region as a result of the Canterbury earthquake sequence. In order to incorporate earthquake resilience into infrastructure repair and design, a cost effective and non-intrusive method of liquefaction mitigation is required. Commonly applied methods…
During past major earthquakes in Christchurch, enormous damage to engineered structures and lifelines has been caused by liquefaction-induced ground failures. Standard penetration test is the most commonly used in situ test for soil characterization of liquefaction resistance. However this test has some limitations. A major…
This paper sets out a simplified approach by which the practical foundation designer can undertake the relevant calculations to satisfy the requirements for deep foundation design in seismic areas. The following matters are dealt with: Design issues that should be addressed; Pile design for axial…
In most design codes, soils are classified as either sand or clay, and appropriate design equations are used to represent their behaviour. For example, the behaviour of sandy soils is expressed in terms of the soil’s relative density, whereas consistency limits are often used for clays. However, sand-clay…
The soil site spectra for site classes D and E in the current NZ design code impose a significant increase in the displacement demands, between 50 and 300% for a structure with a period of 1.0s or longer, compared with a rock site (class A/B)…
During both March and July, 2007 the Far North district of the North Island in New Zealand was hit by a series of severe storm events, which caused over 60 large slope failures along the roading network. Faced with the challenge of remediating such a large number…
This paper describes a case study in Fiji involving the use of pre-loading to accelerate primary consolidation settlement prior to constructing buildings over soft Holocene materials. The pre-loading involved placing a surcharge exceeding the weight of the future structures. Careful monitoring took place to ensure…