Prof Johnson Zhang's Supervisions (5)

PhD
Doctorate

Level	Doctorate
Student	Shen Minhe
Status	Current
Part Time	No
Years	2021
Project Title	Prestressed Bamboo-Timber Composite structure
Awarding Institution	Edinburgh Napier University
Director of Studies	Johnson Zhang
Second Supervisor	Ahmed Mohamed

PhD
Doctorate

Level	Doctorate
Student	Richard Wallace
Status	Current
Part Time	No
Years	2020
Project Title	Development of novel numerical tooling for simulation of subsurface hydrogen and gas mixture storage
Awarding Institution	Edinburgh Napier University
Director of Studies	Zuansi Cai
Second Supervisor	John McDougall
Additional Supervisor	Johnson Zhang

PhD
Doctorate

Level	Doctorate
Student	Dr Bernardino D'Amico
Status	Complete
Part Time	No
Years	2012 - 2015
Project Title	Numerical methods to aid the design of free-form timber grid-shell structures
Project Description	This thesis aims to provide a set of tools for analysis and design of free-form timber grid-shells. It provides a brief introduction on the relationship between shape and structural behaviour of grid-shells, followed by an introduction to actively-bent structural systems. The design issues are then individuated and three main themes are defined, namely: Form-finding, Structural Analysis and Optimisation. The development and use of a numerical framework, based on a six Degree-of-Freedom (DoF) co-rotational beam-element in conjunction with the Dynamic Relaxation method, has formed the basis, on which a unified procedure for the Form-finding and Structural Analysis tasks are denied. A two-step analysis procedure allows seeing a target shape for the grid-shell with the aid of a reference surface, whilst taking into account the effect of internal (bending) reactions on the final geometry. Coupling constraints are numerically simulated by development of a single-node cylindrical joint. An algorithm for grid cutting (mesh manipulation) is described, as well as a modified co-rotational beam-element, based on assumption of ‘equivalent’ bending stiffness. The modified formulation allows taking into account the change in stiffness of the double-layer members, when passing from the Form-finding to the analysis of the structure under working loads, by simply seeing a dimensionless parameter. A numerical framework for optimisation of the members’ cross-section is then introduced. The optimisation problem is decomposed in two main sub-problems, to be separately solved by iterative techniques: e seeking of an ‘allowable’ thickness, for the laths under bending action, is pursued with a procedure based on Newton-Raphson method, whilst: a local-search approach is used to find (for a given load configuration) the optimal variation in thickness of the composite cross-section. The proposed methods are validated by several numerical and full-size experimental test, as well as comparison with the corresponding analytical solution, where available.
Awarding Institution	Edinburgh Napier University
Second Supervisor	Johnson Zhang

PhD
Doctorate

Level	Doctorate
Student	Dr Aamir Khokhar
Status	Complete
Part Time	No
Years	2005 - 2011
Project Title	The use of torsion test method to evaluate the shear modulus and the shear strength of timber joists
Awarding Institution	Edinburgh Napier University
Director of Studies	Johnson Zhang
Second Supervisor	Dan Ridley-Ellis

PhD in Civil Engineering
Doctorate

Level	Doctorate
Student	Dr Ahmed Mohamed
Status	Complete
Part Time	No
Years	2010 - 2016
Project Title	Photogrammetric and stereo vision techniques for evaluating material properties in timber and timber-based composite structures
Awarding Institution	Edinburgh Napier University
Director of Studies	Johnson Zhang