In the previous article “Vertical Transportation Design and Traffic Calculations – Part One”, we explained the following points:
 Applicable Standards and Codes Used In This Course,
 The Need for Lifts,
 The Efficient Elevator Design Solution
 Parts of Elevator System Design Process
 Overview of Elevator Design and Supply Chain Process.
Today we will explain the following points:
 The Concept of Traffic Planning,
 Methods of Traffic Design Calculations
 Principles of Interior Building Circulation.
Sixth:
Introduction to Traffic Planning and Design

1 The Concept of Traffic Planning

As a Vertical transportation system designer, the first
question you will ask to the client is about The building parameters which are listed in step#2 in article “Vertical Transportation Design and Traffic Calculations – Part One”, which were:
The second question will be what is the status of the
building? is it existing or new building? The answer will be used to assign
the tools used to estimate the building population of the building to start
the traffic / circulation planning as follows:
* Patient plus three others (doctors, nurses, porters, etc.).
Table1 Estimation of population
As a general, The Traffic planning in building projects is
dependent on the “traffic analysis” study. We can define the Traffic analysis
study as follows:
The Traffic Analysis Study:
It is the study of
the population distribution and their predicted pattern of flow within the
day.
Therefore, the “traffic analysis” study will vary
according to the
type of building and its use, and the type of occupier. For example, an office building typically requires more
elevators than an apartment building due to heavier loads & traffic.
The traffic analysis study helps in selecting:
In the traffic analysis
study, there are two key factors affecting the
efficiency of an elevator system:
A The Quantity of
Service:
The quantity of service
factor shows how many people will use the lift system over a defined period
of time which is represented by the handling capacity.
The Handling Capacity Of Elevator System:
it is the total number of passengers that the system can
transport within a certain period of time, (usually 5 minutes i.e. 300
seconds) during the peak traffic conditions (usually the morning uppeak)
with a specified average car loading (usually 80% of the rated capacity of
the elevator).
If the
handling capacity of a lift system is too small, there will be lot of people
queuing for the lifts during up peak. Also, the lift cars will have to go
more round trips in order to clear off the queue. Thus system with too small
handling capacity will degrade the quality of service.
B The Quality of
Service:
The quality of service
factor shows how
long the passengers must wait for an elevator and represented by passenger waiting time. The shorter the
passengers waiting time the better the quality of service.
However, passenger
waiting times cannot be easily measured. Some designers, therefore, use the
interval of car arrivals at the main terminal as an indication of service
quality.
The interval of car
arrival of the lift system must be short enough so the handling capacity of
the lift system will be suitable to the arrival rate of the passengers at the
morning 5 minutes uppeak period.
This means
that for efficient lift system design:
Rule#1
The
handling capacity of the lift system ≥ the arrival rate at morning 5 minutes
uppeak period
Otherwise the
design will be nonefficient.
Notes:
As a
conclusion:
the concept
of traffic planning for sizing lift
systems is to match the quality of service (passenger waiting time or arrival rate) with the
quantity of service (handling capacity) and get an economic solution
based on the above Rule#1.

2 Methods
of Traffic Design Calculations

There are (4) methods
used for the traffic design and analysis as follows:
First: Calculation methods,
which includes:
Second: Simulation
methods, which includes:
1 The FormulaBased Method
(Classical Method)
The formulabased method
is based on formulas used to size the lift system to serve the demands of a
building’s occupants by matching the demands for transportation with the
handling capacity of the installed lift system for the worst 5minute period
during the morning uppeak traffic condition to get an economic solution. The FormulaBased Method will not be used for some special conditions like:
2 The Monte Carlo
Simulation Method
The Monte Carlo simulation is a
practical means to calculate the round trip time for an elevator during the
uppeak (incoming) traffic conditions, under a combination of any or all of
the above special conditions (not solved by the FormulaBased Method) such as multiple
entrances, top speed not attained within one or more floor journeys, unequal
floor heights and unequal floor populations.
The block
diagram of the Monte Carlo Simulation method for the calculation of the round
trip time of the elevator during up peak conditions is shown in Fig.1. It
comprises the following main blocks:
In addition a
master module controls the three blocks above to run each block and produce
the final result and interface with the user.
Fig.1: Block diagram of the Monte
Carlo Simulation round trip time tool
3&4  The Simulation methods
They are based on
analysis of a discrete digital simulation of the building, its lifts and the
passenger dynamics with the other major conditions (down peak, interfloor
and twoway). These methods greatly reduces the possibility of errors
compared to the formulabased method and can handle more complex design
cases.
Note:
In this course, we will
explain only the first method which is The FormulaBased Method (Classical
Method).

Important
Notes for Traffic Planning by using The FormulaBased Method (Classical
Method)

From above explanation,
the key parameters in traffic analysis study are as follows :
To design the best
handling capacity of any lift or escalator system, we must start with a
consideration of the traffic flows “circulation” through the building.
Circulation is defined by Dober, 1969 as the act of passing from place to
place.
Building circulation,
both horizontal and vertical, is the lifeblood of any building, and hence if
a successful building is to be designed it is essential that the architect
take expert advice at conception at early stage of the project.

3 Principles of Interior Building Circulation

The study of the circulation of people in the interior of buildings
is very important because it affects the ability of the transportation system
to receive and dispatch the passengers efficiently and effectively. The study
of Interior Circulation is based on many principles which the designer must
be familiar with them, these principles are:

First: Efficiency of Interior
Circulation

The efficiency of
interior circulation inside the buildings is affected by many factors like:

1 Movement Mode:
People will generally
moving horizontally inside their place of work. Then, they may change their
mode of movement from horizontal to vertical, in order to reach a higher or
lower level. To do this they will use stairs, moving walks and ramps
(passenger conveyors), escalators or lifts.

2 Movement Type:
People will move
naturally inside the place without the help of any mechanical equipment
(moving walks and passenger conveyors, escalators or lifts), but when using
moving walks and ramps (passenger conveyors), escalators or lifts, their
movement will be mechanically assisted.
Note:
People are generally
referred to as pedestrians when moving on foot and as passengers when
mechanically transported.

3 Human Behavior:
The movement of people
around a building is a complex movement because each one has:
So, there is
unpredictability in humans behavior reflects to unpredictability in their
movement inside the buildings.

4 Building Shape and
Its Interior Design:
For example, both tall/slender
and low/squat buildings are inefficient while The ideal shape is “compact”.
The circulation efficiency is affected by some factors related to the
interior design of the building like:
So, interior design of the
building
must be coordinated to ensure:
Notes:

Requirements
of Efficient Interior Circulation in a Building
The welldesigned
interior circulation in a building must fulfill the following points:

In the next article, we will continue
explaining other Principles of Interior Building Circulation. Please, keep following.
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