ACI 318 Building Code (American Concrete
Institute)
- provides minimum requirements for the design
and construction of structural concrete members
of any structure
AISC 360 (American Institute of Steel
Construction)
- authoritative reference in the US for
steel building structure design
National Structural Code of the Philippines
(NSCP)
- local counterpart of ACI 318 and governing
code in the Philippines
American Society for Testing and Materials
(ASTM)
- develops and publishes voluntary consensus
technical standards for a wide range of materials,
products, systems, and services
American Association of State Highway and
Transportation Officials (AASHTO)
- specifications, test protocols and guidelines
which are used in highway design and
construction
PNS (Philippine National Standards)
- Local standards formulated by Bureau of
Product Standards (BPS) and/or adopted relevant
international or foreign standards to help
industries produce quality products or services
and raise productivity
Concrete
- safe, strong and simple building material
- made by mixing cement, water, coarse & fine
aggregates, admixtures
- 6% air, 11% portland cement, 41%
gravel/crushed stone, 26% sand, 16% water
Cement
- when mixed with water, forms a paste
- This paste acts like glue and holds or bonds the
aggregates together
●​ Non-hydraulic - Needs dry conditions
and the presence of carbon dioxide (CO₂)
to set and cure.
●​ Hydraulic – The cement hardens by
hydration in the presence of water.
- contains limestone, clay, cement rock, and iron
ore blended and heated to 1200 °C to 1500 °C.
- Gypsum is added to control setting time
Aggregates
●​ Coarse aggregates – crushed rock, gravel
or screenings. Particles greater than
4.75mm and comprises 40% - 45% of the
mixture.
●​ Fine Aggregates – natural sand or
crushed stone with particles smaller than
4.75mm. Generally accounts for 30% 35% of the mixture
Water Cement Ratio
𝑊/𝐶 =
𝑊𝑎𝑡𝑒𝑟 (𝑚𝑙)
𝐶𝑒𝑚𝑒𝑛𝑡 (𝑔)
Subsidiary of International Code Council
(ICC)
- does technical evaluations of building products,
components, methods, and materials
Specific Gravity
𝐺𝑠 =
𝑊 (𝑠𝑝𝑒𝑐𝑖𝑚𝑒𝑛)
(𝐹𝑖𝑛𝑎𝑙 − 𝑖𝑛𝑖𝑡𝑖𝑎𝑙) 𝑟𝑒𝑎𝑑𝑖𝑛𝑔
Construction Material Testing (CMT)
laboratories
- These laboratories fulfill the requirements of
ASTM Engineering Standards
𝐺𝑠 =
ρ𝑚𝑎𝑡𝑒𝑟𝑖𝑎𝑙
ρ𝑤𝑎𝑡𝑒𝑟
Admixtures
●​ Chemical Admixtures - Materials added to
alter the properties of concrete
●​ Mineral Admixtures - augmenting the
strength and density of the finished
concrete
Compaction
- removing the air from concrete
Curing
- keeping concrete damp for a period, to allow it
to reach maximum strength
Weather
- Warmer weather will cause concrete to have a
higher early strength
Type of Cement
- Different types of cement will affect concrete
properties
Slump test
- used to measure the workability of concrete
Compression Test
- shows the best possible strength concrete can
reach in perfect conditions
Defects in Concrete
Color Variation
- Difference in color across the surface of
concrete
- Uneven or variable curing conditions
- Applying a different brand or type of cement to
the surface as ‘drier’
Crazing
- network of fine cracks across the surface of
concrete
- minor surface shrinkage in rapid drying
conditions
Dusting
- fine powder on the concrete surface which
comes off on your fingers
- Finishing before the bleed water has dried
- Not curing properly, or the surface is drying too
quickly
- Concrete subject to severe abrasion or of too
low a grade for the end use
Rain Damage
- surface has bits washed away or many small
dents
- Heavy rain while concrete is setting or rainwater
being allowed to run across the concrete surface
Spalling
- slab edges and joints chip or break leaving an
elongated cavity
- heavy loads or impact with hard objects
- Entry of hard objects into joints
- Poor compaction of concrete at joints
Efflorescence
- white crystalline deposit sometimes found on the
surface of concrete soon after it is finished
- water with dissolved mineral salts collect on the
concrete surface as water evaporates
- Excess bleeding
Honeycombing
- too much coarse aggregate appears on the
surface
- Poor compaction, segregation during placing or
paste leakage from forms
Blistering
- hollow, low profile bumps on the concrete
surface filled with either air or bleed water
- fresh concrete surface is sealed by troweling
while trapping air or bleed water under the surface
Hardwood
- produced from broad leaf trees that lose their
leaves in winter (deciduous)
Softwood
- produced from trees that do not lose their leaves
(coniferous)
- grow much quicker than the hardwood ones
(cheaper and more available)
Engineered Lumber
●​ Laminated Veneer Lumber (LVL) bonding together softwood veneers using
waterproof adhesive
●​ Glued Laminated Lumber (Glulam) bonding several layers of wood together
with strong adhesives
●​ Cross-Laminated Timber (CLT) gluing layers of solid lumber in a
crosswise pattern
●​ I-Beams - with LVL or solid wood
flanges and a plywood or OSB web;
Commonly used for floor and roof joists
Manufactured Board
- made by gluing wood layers or wood fibers
together
Properties of Wood
Anisotropic, Hygroscopic, Viscoelastic
Moisture Content - freshly cut lumber can range
from 30% to 200%
Fiber Saturation Point - point at which the cell
cavities are empty but the cell walls are full of
water
𝑊𝑜𝑜𝑑 𝐷𝑒𝑛𝑠𝑖𝑡𝑦 (ρ) =
𝑂𝑣𝑒𝑛 𝐷𝑟𝑦 𝑀𝑎𝑠𝑠 𝑜𝑓 𝑊𝑜𝑜𝑑
𝑉𝑜𝑙𝑢𝑚𝑒 𝑜𝑓 𝑊𝑜𝑜𝑑
Deterioration
- loss of the ability of a wood product to serve its
intended purpose
Defect
- any irregularity or deviation from the qualities
that make wood suitable for a particular purpose
Polymer
- Natural or Synthetic substance composed of
Macromolecules with repeated monomers
Ceramics
- mixtures of clay, earthen elements, powders, and
water and shaping them into desired forms
Composites
- include concrete, reinforced plastics, cement,
steel– reinforced concrete, and composite
wooden beams