Jun 20, 2008
Testing Building Materials Vital for Construction Industry
Posted by : tootoo
Cement & Sand Privately-promoted building projects have born the brunt of thescourge which has to a large extent spared public-works buildingprojects. Lapses of standard and safely rules are arguably moreprevalent in privately-promoted building projects. The lapses inmany cases are a result of lack of professional input by qualifiedand licensed engineers and architects in spite of technicalcomplexity. The works are also let out to incompetent contractors, they areirregularly procured and engaged without basing on known conditionsof contract. Under such scenario, the risks are transferred tounsuspecting gullible private owners. The need for testing construction materials One industry practice that a number of private developers haveignored yet it has dire consequences is that of testingconstruction materials. Most building constructions like sand,cement, aggregates, timber, steel, water and bricks are used tomake concrete, which is the most widely used material ofconstruction the world over. It is Obvious that there werefatalistic lapses in how these materials were specified and appliedin the works at most of the collapsed buildings, whichcoincidentally were all concrete structures. Improving standards and quality in the construction industry startswith how materials are specified, tested and utilised in works soas not to impair the structural integrity of the resultantbuildings. Uganda consumes about 75,000 tonnes of cement a month and thisconsumption is growing at about 8% a year. Concrete is a complexmaterial of construction whose site use should be competently andprofessionally guided and managed for good results. For instance, the right concrete class must be specified basing onthe level of hostility of the environment which requires properselection and testing of the ingredient materials in competentlaboratories to determine quality and relative quantities toproduce concrete of a desired class. Environment considerations Cement, as the main glue used in concrete, must not only beunadulterated but also be of the type that physically andchemically suits the environment at the site of use. For instance,rapid-setting cement may be used in wet environments where there islikelihood of washout of the fresh paste before it sets andhardens, while sulphate-resisting cement may be used where tracesof sulphate is detected in ground water. It is only throughplanning and testing that these quality breaches may be detectedand avoided. Sand for structural concrete use should be approved only on therecommendation of a qualified material engineer basing onlaboratory test results for strength and purity. The minimum valuerequired of these characteristics exist in specifications but needprofessional input for interpretation and guidance. Aggregates have to be tested to establish not only their mechanicalstrength but also their chemical and mineralogical composition soas to predict their likely reaction with the chemicals in cement.Alkali-silica reactivity is a typical phenomenon that afflicts theintimacy of aggregate and cement paste and leads to unsightlycracks that compromise the strength of the building. This appliesto water for making and curing concrete, timber to support theconcrete in fresh form and steel for reinforcement. Without undertaking rigorous material testing, it is nearlyimpossible to predict and assure the performance of the buildingunder construction and service loads. Unfortunately, niggardlyowners of construction sites are complicit in this undesirablepractice all in the name of cutting costs. In building sites wherematerial testing is strenuously practiced, the structural integrityof the buildings is guaranteed. Role of regulatory bodies The Government-owned Central Materials Laboratory at Kirekaprovides material testing services and technical advice forconstruction works. Some higher institutions of learning andprivate contractors also do the same but to varying levels ofsophistication.
Continuing the discussion
...
TrackBack URL for this entry is :
http://portal.blogfusion.com/_ping.cfm?blogID=5900
http://portal.blogfusion.com/_ping.cfm?blogID=5900
Comments
There are no comments at this time.
Post a Comment
Related Entries
Search
About The Author
Links
Recent Comments
-
Watchesblog:
<
ED Hardy clothing ,Breitling Replica Watches ...
[ View ] -
xiangxiang:
<
Blu RayリッピングiPad動画変換DVDiPad変換iPhone 着メロ作成
[ View ] -
xiangxiang:
<
Blu RayリッピングiPad動画変換DVDiPad変換iPhone 着メロ作成
[ View ] -
yuxuan1515:
<
The biggest surprise on a busy night of inter...
[ View ]
Other Stuff
    |
       |
|
 |