Brick problems Dr S Pavia Dept of Civil Engineering TCD.

Slides:

Advertisements

Similar presentations

EQ: What is chemical and mechanical weathering?

Advertisements

Materials used in the external walls. Brick Bricks are probably the oldest manufactured material we have today. Although the method of production has.

Weathering I. Definitions: the process by which rocks and minerals break down at or near the Earth’s surface Weathering: Produces soil, releases the minerals.

MOULDING SAND Granular particles from the breakdown of rocks by frost, wind, heat and water currents Complex Composition in different places At bottom.

Weathering – the physical & chemical breakdown of rocks. Atmosphere (gas) Atmosphere (gas) Lithosphere (solid) Lithosphere (solid) Hydrosphere (liq.) Hydrosphere.

Chapter 2 Weathering & Soil

CEMENT DEFINITION Cement is often confused with concrete. Cement is a finely ground, usually grey colored mineral powder. When mixed with water, cement.

LECTURE 2 CEMENT.

Mechanical Weathering

Weathering and Erosion

 Rocks are continually recycled on the Earth’s surface and in Earth’s interior, on a geological time scale.  Rock is often exposed to an environment.

Weathering Essential Vocabulary.

Weathering, and Soil Formation

Weathering Processes Formation of Soils By Diana L. Duckworth Rustburg High School Campbell County, VA.

Limestone and its uses. These are chalk cliffs made from a type of limestone formed from the shells of tiny sea plants.

Rock Cycle Metals The Air

Chemical & Mechanical Weathering How is soil formed?

Earth’s Surface: Chapter 4 Section 1 Mechanical and Chemical Weathering Learning Targets: 1) I can describe how mechanical weathering breaks down rocks.

Weathering and Erosion

Weathering. Weathering: the disintegration, or breakdown of rock material.

 M INERALS MAKE UP MOST ROCKS  D IFFERENT MINERALS HAVE DIFFERENT PROPERTIES.  R OCKS ARE BROKEN DOWN TO FORM SEDIMENTS.

Ag.Mechanics Pd. 2,4,5,6.  Name what the two aggregates are in the cement mixture.  What 3 things make up the cement mixture.

Weathering & Erosion.

8-1 Rocks and Weathering How do rocks and weathering affect Earth’s surface? What are the causes of mechanical weathering ands chemical weathering? What.

Weathering Process of disintegration of rock, minerals, and soil.

Sedimentary Processes and products Weathering Processes.

Weathering is the break- up of rock due to exposure to the atmosphere.

Weathering and Soil Formation

Weathering and Erosion. Weathering The process that breaks down rocks and other materials of Earth’s crust into smaller pieces.

1. 2 Engineering Geology and Seismology Lecture#07 Department of Civil Engineering CECOS University of Engineering and Technology, Peshawar.

Chapter 14 Weathering and Erosion

Chapter 6 Weathering and Soil

Weathering. What is Weathering? The physical, chemical, and biological processes that break down rocks and minerals, turning large particles into smaller.

The Chemistry of Limestone. Question 1 The diagram shows a simple lime kiln. When the limestone is heated, it decomposes. Match words from the list with.

The landscape of the Black Mountain Why does it look like this?

WEATHERING Big Rocks Into Small Rocks. 2 Types – Physical/Mechanical & Chemical   Physical/Mechanical Weathering – The physical breakdown of rocks into.

Mechanical and Chemical. _ jpg

Weathering and Erosion

Weathering of Rocks. Why we see weathering 1.Most minerals are not stable at the Earth’s surface 2.The Earth wants to be flat – lowest energy state Topography.

EQ: What is chemical and mechanical weathering?

Who Wants To Be A Millionaire?

The Nature of soil. Dirt is what you find under your fingernails. Soil is what you find under your feet. Think of soil as a thin living skin that covers.

WEATHERING AND EROSION WEATHERING AND EROSION Questions: What is meant by weathering? How does weathering happen? What areas tend to have more weather.

1.Initial setting time of cement:  40 to 60min  30 to 60min  15 to 60min  35 to 60min.

Land and Water Forms Wearing Down Landforms

WEATHERING Breaking down of rock in Earth’s surface.

Rocks and Building 1.5 Cement and concrete. Learning objectives Understand how cement and concrete are produced Understand how cement and concrete are.

Cycles Respiration, Photosynthesis, Evaporation and Condensation, The Weathering of Rock, and the Decay of Organic Matter.

Weathering - the break down of rocks on the Earth’s surface.

PLASTERING AND POINTING Building Construction

Weathering – the physical & chemical breakdown of rocks.

The Shape of the Earths Surface

Weathering – the physical & chemical breakdown of rocks.

3.1 - Weathering Define mechanical and chemical weathering.

CEN 213 CIVIL ENGINEERING MATERIALS

Chapter-3 Bricks.

Civil Engineering Materials

Weathering and Erosion Mr. Scichilone

Bell Ringer What kind of rock is formed by applying heat and pressure to existing rock? What would be required to turn a sedimentary rock into an igneous.

TOPIC INCLUDES- STONE BRICK LIME.

Chapter 5 Weathering, Soils, & Mass Movements

BUILDING STONES A Natural material of construction which is obtained from by suitable method is called a stone. The stone which is used for the construction.

Materials for making concrete

Warm-Up: Thur 5/1 What is the difference between weathering and erosion?

Presentation transcript:

Brick problems Dr S Pavia Dept of Civil Engineering TCD

Cracking caused by rapid heating or cooling. Defective pointing Brick suction rate determines the effectiveness of the bond between mortar and brick. A smoothed vitreous surface will have a lesser bonding capacity.

Aggressive blasting causing entire loss of superficial material or fire skin.

Iveagh buildings near Christchurch Cathedral Clay brick: Material loss by abrasive blasting.

Material loss by abrasive blasting.

Kiss marks dark areas produced on faces of bricks which were in contact during firing. The exposed areas of the brick will be oxidised in the kiln atmosphere during firing whereas the contact faces will experience reduction. Lime-popping or lime-blowing, generated due to expansion induced by hydration of lime particles (limestone fragments in the raw clay would have become lime during firing, when exposed outdoor this lime takes water –slakes- expanding and fracturing the brick).

Scum forms on the brick surface by deposition of sulphur dioxide which originates from sulphur in the raw clay or the kiln fuel.

Black core in a Dublin brick dating from 1780, made with boulder clay and probably clamp fired: ware in contact with fuel (reducing atmosphere, lack of O2 thus no oxidation of C and S within the clay) or insufficient firing time for organic material within the clay (C, S) to burn out (mix with O2).

Presence of cinders, added to the raw clay as a fuel to assist firing.

efflorescence

St Patrick’s Cathedral Memorial Material sulphation resulting from atmospheric pollution Trinity College. Portland stone

Identify causes of decay: a retaining wall, as a result, additional moisture travels through the porous brick. weak porous brick -underfiring materials later introduced in the memorial may be sources of salt. combined action of moisture and salt acting on weak brick has produced material loss and alveolar erosion.