Giới thiệu University of Liverpool

Giới thiệu University of Liverpool

TRƯỜNG ĐẠI HỌC LIVERPOOL

KHOA CÔNG TRÌNH

CÁC DỰ ÁN NGHIÊN CỨU SINH 2004

THÍ NGHIỆM KHÔNG PHÁ HOẠI TRONG XÂY DỰNG CÔNG TRÌNH

Người hướng dẫn : Giáo sư J H Bungey

Công ngh ệ thí nghi ệm kh ông ph á ho ại k ết c ấu đ ư ợc s ử d ụng trong x ây d ựng c ông tr ình cho ph ép x

ác đ ịnh ch ính x ác b ản ch ất v à đi ều ki ện l àm vi ệc c ủa c ác k ết c ấu Khoa c ó r ất nhi ều king nghi ệm v à

th ực ti ễn v ề l ĩnh v ực n ày v à c ó th ể h ư ớng d ẫn NCS v ề c ông ngh ệ v à gi ải th ích roc k ết qu ả

and can offer a range of PhD level work focussing on applications of techniques and interpretation of results The use of such results to permit estimates of future lifetime prediction will be important when planning maintenance and refurbishment programmes, as well as identifying the cause and extent of damage and establishing continued serviceability Such projects are likely to involve a combination of theoretical studies, experimental work (possibly

on site) and computer modelling

A wide range of non-destructive testing techniques are used within Civil Engineering to permit in-situ evaluation and assessment of the nature and condition of structures The Department has extensive experience and expertise in this field and can offer a range of PhD level work

focussing on applications of techniques and interpretation of results The use of such results to permit estimates of future lifetime prediction will be important when planning maintenance and refurbishment programmes, as well as identifying the cause and extent of damage and

establishing continued serviceability M ỗi d ự án th ư ờng bao g ồm s ự k ết h ợp gi ữa nghi ên c ứu l ý thuy ết, c ác c ông t ác th í nghi ệm th ực t ế (c ó th ể ở c ông tr ư ờng) v à m ô h ình m áy t ính

IN-PLACE STRENGTH ASSESSMENT OF HIGH STRENGTH CONCRETE

Supervisors: Professor J H Bungey and Dr M N Soutsos

A range of techniques are available to assess the in-place strength of structural concrete on the basis of non-destructive and partially destructive testing With the growing usage of High Strength Concrete world-wide it is necessary to investigate the applicability of these established techniques to these new materials (which may additionally incorporate fibres) to develop guidelines for the most appropriate testing and interpretation procedures This work would involve theoretical studies, computer modelling and laboratory experimental studies

APPLICATIONS OF SUB-SURFACE RADAR

Supervisors: Professor J H Bungey, and Dr S G Millard.

This approach to investigations within civil engineering has grown in popularity in recent years The department has a strong reputation amongst the world leaders in terms of research into applications/interpretation especially in the field of assessment of concrete structures and bridge

scour problems Current activities involve the use of neural networks and numerical modelling

to assist interpretation, and there is considerable scope for further projects in this area

HIGH PERFORMANCE CONCRETE AND PRECAST CONCRETE PRODUCTS MADE WITH RECYCLED DEMOLITION RUBBLE.

Supervisor: Dr M N Soutsos

For environmental and other reasons the number of readily accessible disposal sites around major cities in the world have decreased in recent years Both disposal volume and maximum sizes of wastes have been restricted The UK Government has taken a proactive stance on this issue and has indicated that as much as 25% of construction aggregate demand should, in future

be met from secondary and recycled sources Large-scale recycling of demolished concrete will contribute not only to the solution of a growing waste disposal problem but will also help to conserve natural resources of sand and gravel and to secure future supply of reasonably priced aggregates for building and road construction purposes within large urban areas It is the purpose

of this research project to examine current concerns with recycled aggregates and to promote their safe and economical use in high performance concrete and precast concrete products This work would involve theoretical studies, computer modelling and laboratory experimental studies

FAST TRACK CONSTRUCTION WITH POZZOLANIC MATERIALS SUCH AS

GROUND GRANULATED BLAST FURNACE SLAG AND PULVERISED FUEL ASH Supervisor: Dr M N Soutsos

The use of ground granulated blast furnace slag (ggbs) and pulverised fuel ash (pfa) and ternary systems with condensed silica fume (csf) in concrete although economic has not gained popularity in fast track construction because of the slower strength gain of these mixes at standard curing temperatures There are however indications that ggbs and pfa are heavily penalised by the standard curing regimes The high early age temperatures occurring inside structural elements appear to provide the activation energy needed for the pozzolanic reaction to

"kick-in" earlier This results in in-situ/air-cured or standard cured strength ratios of 2.0 to 2.4 as compared to ratios of 1.0 to 1.4 for ordinary Portland cement concrete mixes The main aim of this project will be to investigate the early age strength development of ggbs, pfa, ggbs/csf and pfa/csf composite cements under simulated in-situ temperature histories in order to give guidance for their use in fast track construction It is important that techniques for monitoring the strength development on site, e.g., pull-out tests, microcores and maturity measurements, are validated for these composite cements This work would involve theoretical studies, computer modelling and laboratory experimental studies

THERMAL STRESSES IN CONCRETE AT EARLY AGES.

Supervisor: Dr M N Soutsos

Thermal cracking in the structural concrete of foundations, bridges, tunnel linings and other medium-sized elements has become an increasing problem in the past decades Previous methods of predicting thermal cracking and stresses in concrete structures have until now relied entirely on empirical knowledge of previous construction Now, with the advent of powerful computer processing capabilities, it is proposed that a more rigorous and theoretically valid approach needs to be adopted Equipment will be developed together with practical experimental procedures for determining the heat of hydration and early age mechanical properties of concrete specimens undergoing the same temperature cycles as they would in a real structure These will

comprise the increasing compressive and tensile strength, the increase of stiffness and the decrease of relaxation capacity, the coefficient of thermal expansion and the influence of chemical reactions on the deformation These properties can then be used in conjunction with numerical modelling techniques to look at the many ramifications of the heat problem This will include the effects of concrete strength, i.e normal and high, binder type and content, size of structural element, casting and ambient temperatures, formwork type and time of removal on the maximum temperature rise and magnitude of the thermal stresses

ASSESSMENT OF STEEL REINFORCEMENT CORROSION IN STRUCTURAL CONCRETE

Supervisor: Dr S G Millard

The corrosion of reinforcement in steel reinforced concrete structures represents one of the major problems challenging the civil engineering industry with a greater expenditure in the UK

on repair and refurbishment of old structures than on construction of new ones An effective and efficient means of assessing the location and the rate of reinforcement corrosion is required The PhD student will gain familiarisation with the electrochemical methods available of assessing the rate of reinforcement corrosion and will seek to develop new techniques and methodology suitable for a rapid on-site assessment of the magnitude of existing corrosion problems

MIX DESIGN AND MECHANICAL PROPERTIES OF HIGH STRENGTH CONCRETE PRODUCED IN THE UK.

Supervisor: Dr M N Soutsos

Concretes with compressive strengths up to 150N/mm2 now being investigated in laboratories have been the culmination of over 30 years of research within the UK A real attempt to use the material for anything other than academic research will also have to be a gradual process The first step will be to convince consultants and contractors that higher strengths than are currently being used locally are advantageous and higher strength concretes are readily available and can

be produced economically In this project, it is therefore proposed to carry out a national survey

to determine the highest concrete strengths that can be produced on a regional basis These strengths will depend on the regionally available aggregates and ready mixed concrete batching plant facilities If these strengths are to be produced easily and economically then the ready mixed concrete suppliers will need guidelines for the optimisation of the concrete mix proportions for these high strengths In addition the consulting engineering firms will need to be able to predict the properties of these concretes, e.g., moduli of elasticity and rupture and tensile splitting strength, from relationships with compressive strength This project will aim to provide such information

MIX DESIGN, MECHANICAL PROPERTIES AND IMPACT RESISTANCE OF REACTIVE POWDER CONCRETE (RPC).

Supervisor: Dr M N Soutsos, Prof J H Bungey and Dr S G Millard

Ultra high performance fibre reinforced concretes (UHPFRCs) which have been developed in an attempt to improve the mechanical performance of cementitious materials, especially strength and ductility under tension Typical composition of UHPFRC is as follows: A very low water-cementitious ratio ranging from 0.16 to 0.24 achieved by using high cement content (955kg/m3) and a high silica fume content (240kg/m3) and a high dosage of a superplasticiser (15 litres/m3) The only “aggregate” used is fine (150-400 m) quartz sand (1050kg/m3) A high percentage by volume (2.5 to 10%) of special types of steel fibres (24 or 12 mm length and 0.16mm in diameter) are used The compressive strengths of Reactive Powder Concrete, one type of UHPFRC, are likely to be between 170 to 230 MPa depending on the post-set heat treatment (20

to 900C) Values for flexural strengths are likely to be between 30 and 60 MPa, fracture energies between 20,000 and 40,000 J.m-2 and moduli of elasticity between 50 to 60 GPa RPC appears to

be a promising new material not only because of its enhanced ductility but also because the mixing and casting procedures are no different to existing procedures for normal and high strength concretes

The project will aim to supplement and develop existing expertise and data available to the supervisors to permit reliable estimation of the behaviour of RPC under impact and explosion loading conditions This will make use of state-of-the-art equipment, computer modelling techniques and software Specific objectives include:

 Determine guidelines for the production (selection of materials and mix proportions, and curing regimes) of RPCs,

 Experimentally determine the mechanical properties, compressive and flexural strengths, fracture energies, moduli of elasticity, of RPC to provide accurate input data for the computer programs

 Numerically and experimentally investigate the impact load resistance of RPC, with different reinforcement details

 Develop guidelines for the design and detailing of RPC elements to resist impact and explosion loads

 Develop computer simulation programs that will be able to provide accurate predictions of the behaviour of RPC under impact and explosion loading

Success of these objectives can be measured by the ability to develop a library of typical behaviour of RPC under impact and explosion loading situations which will encompass a range

of mix compositions, size of structural element, as well as reinforcement detailing, for direct comparison with laboratory models

FORENSIC AND CONSERVATION ENGINEERING

Supervisor: Mr K G Smith

The study of why things fail invites research into new practices These techniques have applications in the conservation of our oldest and most famous structures It is of commercial, cultural and scientific importance, especially in a cultural centre like Liverpool A multi-disciplinary approach is possible with a specialisation in appropriate aspects For example these could range from structural analysis to construction history Current interests include:

 Stability of listed facades during alterations

 Computer induced failures

 Studies of historical failures and the development of design philosophies

There would be scope for interaction with consulting engineers, government agencies and other universities Applications are encouraged from people wishing to study part-time and those whose first degree is not in civil engineering

MANAGEMENT STUDIES.

Supervisor: Mr K G Smith

From the relatively new discipline of Facilities Management, to conventional project

management, this wide area offers scope for reassessment and improvement of practice It is particularly suitable for mature students with some experience, not necessarily in engineering, and wishing to study part time Current interests include:

 Influence of computers on globalisation of trading practice

 Quality systems take-up in developing economies

 Decision tools for strategic Facilities Management

Some topics may suit overseas students wishing to efficiently transfer best practice by using a combination of analytical and case study approaches in their own country

GEOTECHNICAL ENGINEERING

Supervisor: Dr E A Dickin

Physical modelling of problems in geotechnical engineering can be greatly improved by conducting tests on relatively small models in a centrifuge The models are thereby subjected to the stress levels anticipated by their full-scale prototypes and hence scaling errors are largely overcome The approach has considerable advantages over full scale testing, which is both time consuming and expensive While the centrifuge testing technique is now well established worldwide, very few Civil Engineering Departments in the UK possess such a facility The machine at the University of Liverpool has formed the cornerstone of the experimental research

in geotechnics In general this experimental approach has been carried out in parallel with finite element modelling work using hyperbolic stress/strain models to represent the soil and structure/ soil interface Numerous studies investigating the interaction between soil and retaining or buried structures have been conducted using this philosophy These include the behaviour of piles and pile groups, cantilever and anchor walls, the uplift behaviour of plate anchors, under-reamed piles and pipelines, the moment-carrying capacity of pier foundations and the stability of transmission tower foundations

Studies currently in progress involve:

 The enhancement of the anchoring capacity of a spread foundation by means of geogrid

reinforcement;

 The bearing capacity of shallow foundations subject to inclined and eccentric loading;

 The uplift behaviour of pyramid-shaped transmission tower foundations experiencing

inundation;

 The moment–carrying capacity of railway gantry and mast foundations;

 The influence of soil deposits on the seismic hazard

STRUCTURAL INTERACTION DURING EARTHQUAKES

Supervisors: Mr C Thomas

The theoretical modelling of the dynamic behaviour of structures and also the ground during a seismic event is possible using the finite element technique Although both aspects have been studied in considerable detail the interaction between a structure, ground properties and adjacent

structures has not been fully researched The recent introduction of non-linear elements into the finite element method now allows a reasonably accurate presentation of ground deformations In this proposal the Dyna 3D computer package will be used This package is approved internationally and allows the ground to be represented by non linear elements and also fully allows for structure-ground interaction Liverpool is in the unique position of being allowed the use of this advanced computer package by Ove Arup Associates, as one of the supervisors is closely associated with them

Recent seismic events have shown how identical structures, located close together, have suffered greatly varying damage, this has been graphically shown by the varying degree of collapse of three identical tower blocks in Mexico City Similar behaviour has since been observed in more recent seismic events In this proposal it is intended to use the finite element method to investigate the cause of such varying behaviour of identical and adjacent structures

POUNDING OF ADJACENT STRUCTURES DUE TO VARIABLE GROUND MOTION DURING A SEISMIC EVENT

Supervisor: Mr C Thomas

Several multi-storey structures have recently been completed in city centres Whilst the new structures have been extensively analysed for possible seismic forces nobody has considered the effect on the structures already existing There seems to be a distinct possibility that the ground movement could be modified in intensity and direction, therefore producing twisting movements

in the other structures, which in all possibility have not been designed for such loads The proposal would involve the finite element modelling of a structure and adjacent structures, two dimensionally, and seeing the difference the presence of the second structure has on the behaviour of the first and also any possible modification of the ground movement input This would then be expanded to three dimensional cases such as the three towers in Mexico City that were close together but collapsed in completely different ways It has possibilities in that it could

be expanded to experimental work on the Bristol University shaking table and more complex models Some of the work carried out by Mrs Majid on pounding could be useful in considering the modes of collapse

DIFFUSION OF SEDIMENTS BY SUBMERGED BUOYANT JETS

Supervisor: Dr K H M Ali

Transfer problems in hydraulics are of extreme practical importance The transfer of soluble matter and of discrete foreign particles in turbulent flows are all governed by the same general principles, except for certain special considerations in each case It is extremely useful to predict the distribution of the quantity transferred from a knowledge of the flow characteristics, the physical characteristics of the fluid and of the quantity transferred This topic will deal with the suspended sediment transport in two and three dimensional, horizontal and vertical buoyant jets

in a stagnant ambient fluid and under the influence of a steady current The effect of thermal stratification of the ambient fluid will also be considered The research will involve theoretical and experimental work Instantaneous, continuous and pulsed inputs will be dealt with

LOCAL SCOUR AROUND SINGLE AND MULTIPLE PILES IN UNIFORM, GRADED AND LAYERED SEDIMENT BEDS, WITH SPECIAL REFERENCE TO LIQUEFACTION AND SHEET FLOW

Supervisors: Dr K H M Ali, Dr S Pan and Professor R Burrows

The main objective of this work is to investigate thoroughly the complex three-dimensional scour around single and multiple piles under specific well-defined conditions Work on single piles will involve the study

of:-(i) local scour caused by uniform currents, current and waves and flood and tidal waves

Uniform sediment bed will be used;

(ii) velocity and shear stress distributions in scour holes formed at different times These

will be obtained for deep and very shallow water depths Uniform sediment will be used; (iii) local scour produced by a uniform currents using layered, graded and beds formed from

different mixtures of coarse sand and clay;

(iv) the effect of enhanced turbulence on local scour around a single pile using artificial

roughness elements Uniform sediment will be used;

(v) local scour caused by sheet flow Uniform and graded sediments will be used;

(vi) dishpan scour for different combinations of waves and currents using several

arrangements of multiple piles in the form of offshore structures, uniform sediment will

be used Measurement of pore pressures and verification of three-dimensional numerical pore pressure model

WATER QUALITY MANAGEMENT IN LAKES AND IMPOUNDMENTS

Supervisors: Dr K H M Ali and Professor R Burrows

This research involves various studies into the efficiency of using mixers, jets and air-bubble plumes to break down thermal stratification and improve circulation in large water bodies Of special interest is the reoxygenation potential of these different engineering strategies and their potential impact on algae populations, both aspects being of considerable importance in environmental management

NEARSHORE WAVE/CURRENT CLIMATES

Supervisors: Dr S Pan

Predicting coastal wave/current climates using computer models has been a major topic in the Department for many years and has been worked on by a range of previous PhD students During the past decades, the Maritime research group in the Department has accumulated a considerable volume of data from large scale laboratory experiment, such as the UK Coastal Research Facility (CRF) at HR Wallingford and from fields in both the UK and Europe through the EPSRC and EU funded projects, which have been focused on investigating the hydrodynamics and morphodynamics due to waves and tides

A recently completed EU project, which involved international collaborations with 21 institutes and was co-ordinated by Professor O’Connor, was to study the tidal inlet dynamics using a site

at Algarve, southern Portugal In this project, a wide-range of remote sensing equipments, including HF Radar, X-Band Radar, Video monitoring system as well as ADV, ABS systems, have been used to measure the wave and current conditions, while a variety of computer models, ranging from 1D to 3D, have been also used to achieve better understanding of hydrodynamics and morphodynamics behind the capacity of the field measurements and in greater details The data sets obtained from these research projects are unique and valuable for calibrating and

validating the computer models, some of which have not been fully processed Opportunity exists, therefore, for computer literate students to undertake a PhD study in the area of computer modelling of near-shore circulations using the existing data sets In addition, the student would also become involved in the design and collect new laboratory and field data at sites both in the

UK and Europe through the on-going EPSRC and EU sponsored projects

INVESTIGATION OF THE DYNAMICS OF HIGH CONCENTRATION MUD SUSPENSIONS AND FLUID MUD

Supervisors: Dr K H M Ali, Dr S Pan and Professor R Burrows

This research will enhance understanding of the behaviour of High-Concentrated Mud Suspensions (HCMS) and Fluid Mud under a variety of flow conditions using the Liverpool Race Track Mud Flume and the Liverpool Wind-Wave-Current Flume Investigation of the following objectives will be made:

(i) Influence of suspensions of cohesive sediment on the turbulent flow structure;

(ii) Incorporation of more sediment fractions into recent flocculation models;

(iii) Erosive and mixing capability of waves;

(iv) parameterisation of latest flocculation model results to ease their use in

three-dimensional numerical cohesive transport models This research will entail extensive numerical and physical modelling

EXPERIMENTAL STUDIES IN OPEN CHANNEL FLOW AND HYDRAULIC STRUCTURES.

Supervisors: Dr K H M Ali and Professor R Burrows

Interesting studies on various aspects of environmental hydraulics often arise from consultancy activities and these can normally be extended into PhD and MPhil research Notable earlier examples include model studies on storm overflow structures, siphons and pump sumps in urban drainage and weir, spillway and control gate studies in dam and river engineering

HYDRAULIC CONDITIONS WITHIN LONG SEA OUTFALL DIFFUSERS

Supervisor: Dr K H M Ali and Professor R Burrows.

An experimental and analytical study will be conducted on stratification and salt-wedge formation in long sea outfalls Detailed velocity measurements will be made using a new ultrasonic velocity meter Interfacial shear stresses and friction factors will be calculated Detailed velocity-measurements will also be made to study the effect of bed forms obtained using cohesive and non-cohesive sediments The experimental results will be compared with predictions from the FLUENT computational fluid dynamics software package

WATER QUALITY MANAGEMENT IN RIVERS SUBJECT TO TIDAL SALT INTRUSION

Supervisors: Professor R Burrows and Dr K H M Ali

An investigation of natural processes of mixing and entrainment between the fresh and salt waters will be conducted using both experimental (laboratory) methods and Computational Fluid Dynamics(CFD) through the FLUENT -computer package The rivers Tyne and Lagan (Belfast),

as well as the ‘barraged’ Tawe in Swansea and Wansbeck (Nothumberland) will be considered

as initial case studies Special attention will be given to the viability of introduction of artificial

means of mixing (through air injection, jets or propeller mixers) to remedy problematic water quality conditions such as low levels of dissolved oxygen etc The study might also extend to further development of novel systems for control of saline intrusion Some collaboration with a leading environmental consultancy firm can be expected

POLLUTION IMPACTS FROM COASTAL WASTEWATER OUTFALLS.

Supervisors: Professor R Burrows, Dr K H M Ali, and Dr S Pan.

The study may consider the case of single point and continuous thermal discharge from power stations or multi-point intermittent shoreline spills from urban drainage systems following storm rainfall Numerical modelling studies are envisaged based on in-house 3-D numerical codes capable of representing tide current and wave impacts on nearshore water circulation Dispersion

of both suspended and particulate pollutants might be investigated

STUDY OF PRESSURE TRANSIENTS (‘WATERHAMMER’) IN PIPELINES

Supervisor: Professor R Burrows

A computational study drawing from earlier MPhil work on the effect of air pockets on the surge pressures resulting from pump-start or pump-trip etc The ultimate aim will be to establish software capable of conducting a diagnostic assessment of the operational state of a dedicated pumping main, including detection of leakage Some collaboration with other EC researchers and the Water Utility Companies can be expected, the latter providing the possibility of field data collection

ADVANCES IN THE MANAGEMENT OF WATER DISTRIBUTION

Supervisors: Professor R Burrows and Dr T T Tanyimboh

Continuation of recent PhD level work into such topics as hydraulic modelling of flows and pressures in pipe networks; characterisation and specification of demand; system reliability and operation under partial failure; and innovative developments in information systems, etc Close association with the local consulting sector can be expected together with collaboration from Water Utility Companies and possibly software developers/suppliers The work will involve familiarisation with such commercial support systems as Stoner, Watnet and Epanet for network modelling and Mapinfo and Strumap for GIS, in addition to extensive use of databases

REAL-TIME CONTROL OF LARGE SEWERAGE SYSTEMS FOR ENVIRONMENTAL AND ECONOMIC BENEFITS

Supervisors: Professor R Burrows

Continuation of current PhD work being conducted with the assistance of North West Water and Bechtel, and expected later to involve also the Environment Agency The present project is focused on the development of an optimal control strategy for the 28km long Liverpool Interceptor Sewer to minimise impacts of spill discharges to the river from 28 major storm overflow structures Candidate methods based on linear or dynamic programming are presently under investigation Initially overlapping with the present programme, it is expected that some further evaluation of these approaches will be tackled in the new study, to cater for more usual multi-branched network configurations Additionally, further developments in sub-catchment flow synthesis and appraisal/integration of data acquisition needs will be pursued, as a preliminary to implementation of the approach to the Liverpool case study and the assessment of its performance

RISK ASSESSMENT OF COASTAL DEFENCES

Supervisor: Eur Ing T S Hedges

Risk analysis provides a powerful framework for the design of coastal defences But progress has been slow in formulating methods and gaining confidence in design procedures based upon risk analysis At present, knowledge of coastal structures is insufficient to permit a full assessment of their safety Nevertheless, it is possible to assess their safety against specific types

of failure (i.e to consider only single failure modes)

Hedges & Reis (1999) start with a review of single failure mode probabilistic methods and introduce software which uses the Level II First Order Reliability Method (FORM) Known as PARASODE (Probabilistic Assessment of Risks Associated with Seawall Overtopping and Dune Erosion), the program concentrates on the failure modes of random wave overtopping of simple embankment seawalls and of erosion to dunes The quantity of wave overtopping is calculated using both the H&R formula and Owen's formula (Hedges & Reis, 1998); dune erosion is calculated using Vellinga's model (Vellinga, 1983) Despite its name, much of PARASODE is generic and can be adapted to other types of failure without undue difficulty Future research will continue the development of PARASODE

RANDOM WAVE OVERTOPPING OF SEAWALLS

Supervisor: Eur Ing T S Hedges

Seawalls are expensive, and fixing a seawall freeboard at too large a value has both a financial penalty and is unnecessarily damaging to the natural environment owing to the increased impact

of the structure on its surroundings On the other hand, if the crest of a seawall is set too low, then there are potential problems with structural safety and flooding from wave overtopping Hence, it is important to strike the correct balance between satisfying the structural and functional requirements of the project, avoiding unnecessary expense, and having undesirable impacts on the surrounding environment

The prediction of wave overtopping rates is usually based on empirical equations fitted to laboratory data These equations do not have any theoretical basis However, a new model has now been developed by Hedges & Reis (1998) which, unlike earlier expressions, accounts for the fact that no overtopping (apart from wind-blown spray) occurs if the seawall freeboard exceeds the maximum wave run-up on the face of the structure This fact is of practical importance because allowable overtopping discharges to ensure the safety of people and property are quite small Future research will continue development of the Hedges & Reis model

ROAD SAFETY

Supervisor: Dr L J Mountain

Road accidents are currently the eighth largest cause of death in the world and over 45,000 people are killed in road accidents in the EC alone Although Great Britain has the second best safety record in Europe (after Sweden), some 10 people are still killed on our roads every day and our child pedestrian safety is one of the worst in Europe Further research is thus vital The Department has had an active programme of road safety research for more than ten years, concentrating particularly on the statistical analysis of accident data (predictive accident