Soil Characterisation using Screw Driving Sounding (SDS) data

Research papers, The University of Auckland Library

The Screw Driving Sounding (SDS) method developed in Japan is a relatively new insitu testing technique to characterise soft shallow sites, typically those required for residential house construction. An SDS machine drills a rod into the ground in several loading steps while the rod is continuously rotated. Several parameters, such as torque, load and speed of penetration, are recorded at every rotation of the rod. The SDS method has been introduced in New Zealand, and the results of its application for characterising local sites are discussed in this study. A total of 164 SDS tests were conducted in Christchurch, Wellington and Auckland to validate/adjust the methodologies originally developed based on the Japanese practice. Most of the tests were conducted at sites where cone penetration tests (CPT), standard penetration tests (SPT) and borehole logs were available; the comparison of SDS results with existing information showed that the SDS method has great potential as an in-situ testing method for classifying the soils. By compiling the SDS data from 3 different cities and comparing them with the borehole logs, a soil classification chart was generated for identifying the soil type based on SDS parameters. Also, a correlation between fines content and SDS parameters was developed and a procedure for estimating angle of internal friction of sand using SDS parameters was investigated. Furthermore, a correlation was made between the tip resistance of the CPT and the SDS data for different percentages of fines content. The relationship between the SPT N value and a SDS parameter was also proposed. This thesis also presents a methodology for identifying the liquefiable layers of soil using SDS data. SDS tests were performed in both liquefied and non-liquefied areas in Christchurch to find a representative parameter and relationship for predicting the liquefaction potential of soil. Plots were drawn of the cyclic shear stress ratios (CSR) induced by the earthquakes and the corresponding energy of penetration during SDS tests. By identifying liquefied or unliquefied layers using three different popular CPT-based methods, boundary lines corresponding to the various probabilities of liquefaction happening were developed for different ranges of fines contents using logistic regression analysis, these could then be used for estimating the liquefaction potential of soil directly from the SDS data. Finally, the drilling process involved in screw driving sounding was simulated using Abaqus software. Analysis results proved that the model successfully captured the drilling process of the SDS machine in sand. In addition, a chart to predict peak friction angles of sandy sites based on measured SDS parameters for various vertical effective stresses was formulated. As a simple, fast and economical test, the SDS method can be a reliable alternative insitu test for soil and site characterisation, especially for residential house construction.

Upon the Upland Road Photograph 1

Images, UC QuakeStudies

A photograph of the installation 'Upon the Upland Road' on the former site of the Harbour Light in Lyttelton. The installation shows the last three lines of James K Baxter's poem, 'High Country Weather', written in the nautical flag alphabet.

Upon the Upland Road Photograph 2

Images, UC QuakeStudies

A photograph of the installation 'Upon the Upland Road' on the former site of the Harbour Light in Lyttelton. The installation shows the last three lines of James K Baxter's poem, 'High Country Weather', written in the nautical flag alphabet.

Paul and Sam Corliss's Street Art Photograph (2012:11:06 03:44:18)

Images, UC QuakeStudies

A photograph of street art attached to a fence in the former site of a building on the corner of Bowhill Road and Marine Parade. The artwork has been created on a sheet of metal and depicts ChristChurch Cathedral.

Simulation and Validation of Topographic Effectds on Mt Pleasant, Christch…

Research papers, University of Canterbury Library

Damage distribution maps from strong earthquakes and recorded data from field experiments have repeatedly shown that the ground surface topography and subsurface stratigraphy play a decisive role in shaping the ground motion characteristics at a site. Published theoretical studies qualitatively agree with observations from past seismic events and experiments; quantitatively, however, they systematically underestimate the absolute level of topographic amplification up to an order of magnitude or more in some cases. We have hypothesized in previous work that this discrepancy stems from idealizations of the geometry, material properties, and incident motion characteristics that most theoretical studies make. In this study, we perform numerical simulations of seismic wave propagation in heterogeneous media with arbitrary ground surface geometry, and compare results with high quality field recordings from a site with strong surface topography. Our goal is to explore whether high-fidelity simulations and realistic numerical models can – contrary to theoretical models – capture quantitatively the frequency and amplitude characteristics of topographic effects. For validation, we use field data from a linear array of nine portable seismometers that we deployed on Mount Pleasant and Heathcote Valley, Christchurch, New Zealand, and we compute empirical standard spectral ratios (SSR) and single-station horizontal-to-vertical spectral ratios (HVSR). The instruments recorded ambient vibrations and remote earthquakes for a period of two months (March-April 2017). We next perform two-dimensional wave propagation simulations using the explicit finite difference code FLAC. We construct our numerical model using a high-resolution (8m) Digital Elevation Map (DEM) available for the site, an estimated subsurface stratigraphy consistent with the geomorphology of the site, and soil properties estimated from in-situ and non-destructive tests. We subject the model to in-plane and out-of-plane incident motions that span a broadband frequency range (0.1-20Hz). Numerical and empirical spectral ratios from our blind prediction are found in very good quantitative agreement for stations on the slope of Mount Pleasant and on the surface of Heathcote Valley, across a wide range of frequencies that reveal the role of topography, soil amplification and basin edge focusing on the distribution of ground surface motion.

Observatory Tower Photograph 28

Images, UC QuakeStudies

A photograph of the rubble of the Observatory tower in the South Quad of the Christchurch Arts Centre. The tower collapsed during the 22 February 2011 earthquake. A digger was used to clear the rubble away from the building. In the foreground is Chris Whitty, Site Manager of the Christchurch Arts Centre.

Photograph by Neil Macbeth 648

Images, UC QuakeStudies

A view across Worcester Street in Linwood to a block of shops, including Easy Traders Whiteware and Furniture. Masonry, structural components and the Easy Traders building's veranda have collapsed onto the road. The whole back section of the shops has also collapsed. The site is enclosed by a safety fence.

Julia Holden's 2013 Photographs 162

Images, UC QuakeStudies

A photograph of the corner of Manchester Street and Cashel Street. The site has been fenced off and there is building rubble on the ground. There is a coloured tape installation on the fence, and an image of Homer Simpson on the exposed wall of the second storey of the building.

BeckerFraserPhotos October 2011 photograph 597

Images, UC QuakeStudies

Photograph captioned by BeckerFraserPhotos, "The city blocks encompassed by Manchester Street, Gloucester Street, Latimer Square and Hereford Street are amongst those with the most demolished buildings in the city centre at the moment".

BeckerFraserPhotos March 2012 photograph 010

Images, UC QuakeStudies

A shield on the side of one of the Wards Brewery buildings, also known as the Crichton Cobbers site. The photograph has been captioned by BeckerFraserPhotos, "These decorative shields, which are still intact, are a good example of the fine workmanship that was found on this industrial complex of buildings".

Milk Fight Photograph 3

Images, UC QuakeStudies

A photograph of participants signing in at the registration table for Milk Fight - a dairy-fuelled urban food fight by local artist Gaby Montego. The event was part of FESTA 2014. Milk Fight was held on the former Convention Centre site at 100 Peterborough Street.

Milk Fight Photograph 13

Images, UC QuakeStudies

A photograph of local artist Gaby Montejo in a cow onesie before his Milk Fight event. Milk Fight was a dairy-fuelled urban food fight, which was part of FESTA 2014. It was held on the former Convention Centre site at 100 Peterborough Street.

Milk Fight Photograph 12

Images, UC QuakeStudies

A photograph of local artist Gaby Montejo in a cow onesie before his Milk Fight event. Milk Fight was a dairy-fuelled urban food fight, which was part of FESTA 2014. It was held on the former Convention Centre site at 100 Peterborough Street.

Julia Holden's 2013 Photographs 163

Images, UC QuakeStudies

A photograph of the corner of Manchester Street and Cashel Street. The site has been fenced off and there is building rubble on the ground. There is a coloured tape installation on the fence, and an image of Homer Simpson on the exposed wall of the second storey of the building.

BeckerFraserPhotos December 2011 photograph 0337

Images, UC QuakeStudies

An aerial photograph captioned by BeckerFraserPhotos, "Central city blocks bounded by Colombo Street, Hereford Street, Cashel Street, and High Streets".

WEMO ERT Set 1 - March 2011 - Photograph 78

Images, UC QuakeStudies

A photograph of the earthquake-damaged Oxford Terrace Baptist Church. Steels bracing has been used to stabilise the front of the building. Crumbled masonry and other rubble is still lying in front. Wire fences have been placed around the building site as a cordon.

WEMO ERT Set 1 - March 2011 - Photograph 77

Images, UC QuakeStudies

A photograph of the earthquake-damaged Oxford Terrace Baptist Church. Steels bracing has been used to stabilise the front of the building. Crumbled masonry and other rubble is still lying in front. Wire fences have been placed around the building site as a cordon.

Milk Fight Photograph 4

Images, UC QuakeStudies

A photograph of Melanie Oliver (Director, The Physics Room), addressing participants and spectators at Gaby Montejo's Milk Fight. This dairy-fuelled urban food fight was part of FESTA 2014, and was held on the former Convention Centre site at 100 Peterborough Street.

BeckerFraserPhotos March 2012 photograph 009

Images, UC QuakeStudies

A shield on the side of one of the Wards Brewery buildings, also known as the Crichton Cobbers site. The photograph has been captioned by BeckerFraserPhotos, "These decorative shields, which are still intact, are a good example of the fine workmanship that was found on this industrial complex of buildings".

Ray Whelan WEMO Photograph 20

Images, UC QuakeStudies

A photograph of the site of a demolished building on Gloucester Street, near the intersection of Colombo Street. A Southern Demolition excavator is being used to clear the rubble away. In the background are the Forsyth Barr building, the Copthorne Hotel and the PricewaterhouseCoopers building.

Photograph of Pavilions & Lighting Devices 2012:10:19 17:23:13

Images, UC QuakeStudies

A photograph of organisers of LUXCITY on the corner of Manchester Street and Gloucester Street. A site hazards board is leaning against a white van, in front of students in high-visibility vests who are setting up the Pavilions & Lighting Devices market.

BeckerFraserPhotos November 2011 photograph 105

Images, UC QuakeStudies

Photograph captioned by BeckerFraserPhotos, "Site of the old Press Building in Cathedral Square and from left to right, Novatel Hotel, Price Waterhouse Coopers Building, Isaac Theatre Royal (behind the crane), new Press Building, Tramway Junction with the Rendevous Hotel showing above".

Photograph by Neil Macbeth 586

Images, UC QuakeStudies

A view across London Street in Lyttelton to The Volcano Cafe, The Lava Bar, and Coastal Living Design Store. Masonry from the buildings has collapsed onto the footpath, and the site has been cordoned off with wire fencing. The buildings' yellow recycling bins are still waiting on the curb for collection.

Photograph of Gap Filler project 13 (6)

Images, UC QuakeStudies

A garden in Sydenham created by Greening the Rubble, a community project in Christchurch which aims to create temporary public parks and gardens on the sites of demolished buildings. To the left, the 10 square metre office building can just be seen as well as a mural in the background.

BeckerFraserPhotos February 2011 photograph 185

Images, UC QuakeStudies

Scaffolding that has been constructed on the Manchester Street face of the Octagon Live Restaurant (formerly Trinity Church), which is being repaired. Masonry has fallen from one of the building's gables, and the resultant gap has been weather proofed with plywood and a tarpaulin. The site has been enclosed in a safety fence that cuts off one lane of the road.

BeckerFraserPhotos December 2011 photograph 0349

Images, UC QuakeStudies

An aerial photograph of the Majestic Theatre on the corner of Lichfield and Manchester Street. The photograph has been captioned by BeckerFraserPhotos, "Cashel Street running across the top of the photograph from Manchester Street (just out of shot on the left of the photo) towards Madras Street. Avonmore House is now an empty site".

River of Flowers - Te Waitohi Maumahara

Images, eqnz.chch.2010

Friday 22 February 2013. Official Supported Site for River of Flowers: Horseshoe Lake Riverbank on Lake Terrace Road, opposite the bus stop between Oregon and Tangmere Places Hosted by: Burwood Primary School and Community. File reference: CCL-2013-02-22-River-of-FlowersDSC_03401.JPG From the collection of Christchurch City Libraries. ...

BeckerFraserPhotos October 2011 photograph 410

Images, UC QuakeStudies

A pile of rubble from a demolished building on Worcester Street. In the background, the partially demolished Warners Hotel can be seen as well as the Novotel and the PricewaterhouseCoopers Building in the distance. A digger and long-reach excavator can also be seen.

BeckerFraserPhotos February 2011 photograph 181

Images, UC QuakeStudies

Scaffolding that has been constructed on the Manchester Street face of the Octagon Live Restaurant (formerly Trinity Church), which is being repaired. Masonry has fallen from one of the building's gables, and the resultant gap has been weather proofed with plywood and a tarpaulin. The site has been enclosed in a safety fence that cuts off one lane of the road.

Photograph by Neil Macbeth 271

Images, UC QuakeStudies

A member of the New Zealand Fire Service in a cherry picker spraying water at the fire burning in the collapsed Canterbury Television Building. Smoke is billowing out of the intact section of the building. Below, emergency personnel are searching the rubble for trapped people. A piece of corrugated plastic is being used to slide pieces of debris off the site.