Report on Site Visit at Thomson Road

Prepared for

Mr Tan Kim Leong

Lecturer

Singapore Polytechnic

By

Fairuz Sufyan

Student, DCEM/FT/2B/04

Singapore Polytechnic

Content

Summary

1. Introduction1.1 Purpose1.2 Background1.3 Method of Investigation1.4 Scope of Investigation

2. Machineries and plants 2.1 Machineries used2.2 Plants used

3. Substructure System4. Method Statement on Site Visit

4.1 Safety4.2 Piling

5. Types of Geotechnical Ground Instruments

Appendix

References

Summary

On the 23/11/2009, we went to the VIVA site @ Thomson Tiong Aik Site for some hands on/review on an actual construction site. The objective of the site visit was mainly to familiarise ourselves with the operations at a construction site.

During the site visit, we were exposed to various construction methods, machineries and also had the chance to observe the construction of piles. At that time of the visit, the construction works were only at the piling stage. Thus, there was nothing much to observe. However, we were also given the opportunity to experience the construction machineries at work. We learnt the importance of a tidy and organised working environment, as well as safety equipments.

The site consisted of many possible death threats or potential threats where fatal accidents can occur. Upon arrival, we were all inspected – the management had to ensure that we were all properly attired with safety gear and covered shoes before we were allowed to go in. It was a standard protocol at all construction sites. Safety is after all the most important aspect in a construction project.

This outdoor experience provided us with a more in-depth and hands on experience on Civil Engineering Construction. We were able to question, understand and absorb the logic behind the machineries, construction techniques, and methodology theory learnt in class.

Fairuz SufyanDCEM/FT/2B/0

1. Introduction1.1 Purpose of visit –

The purpose of the site visit was simple – we needed to understand and visualise the theory taught in class. The site visit would allow us to have a hand on review and a clear understanding on constructing.

1.2 Background –

Developer of VIVA : Thomson Peak Pte Ltd (Subsidiary of Allgreen Properties Limited)

The proposed condominium would consist of 3 – blocks of 30 – storey condominium with a basement car park, communal facilities and a swimming pool.

Site Location: 28, Suffolk Walk

Site Area: 11,901.30 sq m / 128,105.59 sq ft

Total Units: 235

Expected Date of Completion: 30 June 2016

Recreational Facilities @ Viva:

Lap PoolKids PoolJacuzzi Kids PlaygroundBBQ PavilionsLandscape PavilionsTennis CourtsBasketball Half-CourtGolf Practice RangeBadminton CourtOutdoor Fitness StationsFunction Room With GymChildren's Room

Project Consultant:

Architect : Design Link Architects

Landscape Consultant

: Belt Collins International (S) Ltd

Showflat ID : Suying Design Pte Ltd

Main Contractor : Tiong Aik Construction Pte Ltd

Solicitor :

Ramdas & Wong36, Robinson Road, #10-01, City House Singapore 068877

1.3 Method of Investigation

All data collated for the report have been gathered from various internet websites, and the during the site visit itself.

1.4 Scope of Investigation

The collated data has been cross referred for validity in this (VIVA) project.

2. Machineries and Plants

2.1 Machineries

i) Excavator

A Caterpillar excavator has a backhoe with "thumb" attachment. The bucket is raked toward the machine to create a trench or pit. The lower jaw "thumb" enables large objects to be moved and 'grabbing' building components during demolition. Most excavators have the bucket fitted without the thumb attachment.

ii) Bulldozer

A bulldozer is a crawler (caterpillar tracked tractor), equipped with a substantial metal plate (known as a blade) used to push large quantities of soil, sand, rubble, etc., during construction work and typically equipped at the rear with a claw-like device (known as a ripper) to loosen densely-compacted materials.

iii) Pile Driver

A pile driver is a mechanical device used to drive piles into soil to provide foundation support for buildings or other structures. The term is also used in reference to members of the construction crew that work with pile-driving rigs.

iv) Crane

A crane is a lifting machine, generally equipped with a winder (also called a wire rope drum), wire ropes or chains and sheaves, that can be used both to lift and lower materials and to move them horizontally. It uses one or more simple machines to create mechanical advantage and thus move loads beyond the normal capability of a human. Cranes are commonly employed in the transport industry for the loading and unloading of freight, in the construction industry for the movement of materials and in the manufacturing industry for the assembling of heavy equipment.

(Picture of crane parts : http://en.wikipedia.org/wiki/File:Crane_machine_slewing_platform.svg)

3. Substructure System

Substructure system of the Site

During the site visit, I noticed how well the place was organised. There were sufficient and adequate substructures used to aid in the construction of the site.

There were various platforms and supports that were visible. The platforms were made to support the load of the machineries as well as the workers.

It is evident that sub structuring before a project is imminent is important.

Substructures aid constructors in building the primary structures.

4. Method Statement

4.1 Safety

The first step to determining a good construction environment would be safety. The emphasis for safety can never be enough – everyone working at the construction site would have to be geared with safety equipments. Some of the basics are like wearing a helmet, and wearing boots. This is to ensure that we would be less vulnerable to accidents.

With safety covered, workers are prepared/geared to do most of the construction jobs. There are some that still require some profession.

This is a construction technique in a way because it boosts morale by giving everyone that security of being safe, or less prone to accidents.

The safety precautions needed during the piling works are as followed:

- Safety helmet- Adequate support of all sides of excavation to prevent soil movement.- Adequate support of adjacent structures to be maintained.- Maintain safe access and exit to basement at all times.- Wear protective clothing including a belt/harness.- Erect barricades/barriers around excavated site to prevent people from

accidentally falling in.

These few precautions are visible during our site visit.

4.2Piling

During our visit, we only witnessed the early stages of a construction project. At the site, we were only able to see half-built piles. Therefore it can easily be said that they are still constructing the piles. However, I was unable to know for sure if a pile driver was used to drive the pile in. The picture provided below shows the workers and machineries being used. The erected columns visible are the incomplete piles.

Basement Excavation

The following are the common methods of excavating a basement:• Open-cut method.• Excavation supported by cofferdams.• Excavation supported by reinforced concrete diaphragm walls constructed in advance ofthe main excavation.• Excavation supported by contiguous bored piles or secant piles walls constructed inadvance of the main excavation.• Excavation supported by soldier pile walls.Whichever method is chosen, it is essential that the ground water is properly controlled.

Soldier Piles

The excavation is supported by soldier piles. Soldier piles consist of horizontal timber lagging that spans across a series of vertical wide flange steel members embedded into the ground.

They often use temporary retaining structures for excavation and construction of a basement.

These temporary structures are visible in the picture above.

The method consists of boring holes along the wall line, typically 2 to 3 m centres, placingvertical steel soldier piles within the holes and concreting the base of each joist below finalformation level. As earth is removed, horizontal timber lagging are wedged between thesoldier piles to retain the soil outside the excavation. The soldier piles and lagging may beremoved after construction of the basement has been completed.

5. Geotechnical Instrumentations

What is Geotechnical Engineering?

Geotechnical engineering is the branch of civil engineering concerned with the engineering behavior of earth materials. Geotechnical engineering includes investigating existing subsurface conditions and materials; determining their physical/mechanical and chemical properties that are relevant to the project considered, assessing risks posed by site conditions; designing earthworks and structure foundations; and monitoring site conditions, earthwork and foundation construction.

i) Geotechnical Engineering is used to analyse the ground/soil of the planned site.

Inclinometers – to monitor lateral movements in embankments and landslide areas, deflectionof retaining structures and piles, and deformation of excavation walls. It is installed in a nearvertical borehole that passes through suspected zones of movement into stable ground.

Water Standpipes - to monitor the ground water level, control the rate of dewatering inexcavation work and monitor seepage. It involves drilling a 150 mm borehole to the requireddepth, lowering the 50 mm standpipe into the borehole, backfill with sand, terminate thetubing at the surface and place a protective cap at the top of the tube.

Pneumatic Piezometers - to monitor pore pressure, to determine the stability of slopes,embankments and ground water movement.

Tilt Meters - to monitor changes in the inclination of a structure, to provide an accuratemovement of a structure and early warning of potential structural damage.

ii) Managing the instruments

It is vital to provide protection to these instruments from damage as this could lead tointermittent or complete loss of acquisition of data. Instrumentation readings can be collectedlocally or using data-loggers to provide real-time monitoring for critical areas of theconstruction to ensure grester safety on site. In order for such a comprehensiveinstrumentation scheme to be effective, it is essential that the following rules be observed:• The instrumentation must be installed properly.• The reading must be taken and recorded properly.• The readings must be interpreted correctly.Any signs of abnormal ground movement must be communicated immediately to all partiesinvolved in the construction so that effective remedial actions can be taken in a timely manneror contingency plans activated.

These are common instruments that can be found at excavation sites.

Appendix

Proposed Architecture of the VIVA condominium.

Site Plan

References

http://www.soilreport.net/soil.html

http://www.asiabuilders.com/asiabuilders/Cranes_Singapore_Product_Listing_C1_CONC64500.aspx

http://www.viva-singapore.com/amenities.html

http://en.wikipedia.org