Multifractal to monofractal evolution of the London's street network

TL;DR

This study analyzes London's street network evolution from 1786 to 2010, showing a transition from multifractal to monofractal structure, influenced by growth constraints like a green belt, using multifractal analysis and simulations.

Contribution

It demonstrates the multifractal to monofractal transition in London's street network and links it to growth constraints, providing new insights into urban morphological evolution.

Findings

London's street network evolved from multifractal to monofractal.

Growth constraints like a green belt influence fractal evolution.

Simulations show constrained diffusion limited aggregation leads to monofractality.

Abstract

We perform a multifractal analysis of the evolution of London's street network from 1786 to 2010. First, we show that a single fractal dimension, commonly associated with the morphological description of cities, does not su ce to capture the dynamics of the system. Instead, for a proper characterization of such a dynamics, the multifractal spectrum needs to be considered. Our analysis reveals that London evolves from an inhomogeneous fractal structure, that can be described in terms of a multifractal, to a homogeneous one, that converges to monofractality. We argue that London's multifractal to monofracal evolution might be a special outcome of the constraint imposed on its growth by a green belt. Through a series of simulations, we show that multifractal objects, constructed through di usion limited aggregation, evolve towards monofractality if their growth is constrained by a non-permeable boundary.