Soil and Earth Works Introduction to construction Industry Faculty of Applied Engineering and Urban Planning Introduction to construction Industry Civil Engineering Department 2nd Semester 2008/2009 Soil and Earth Works Lecture 2 - Week 1 UP Copyrights 2008

Content Objectives, components, applications of Soil Index Properties of soil. Types of Soil Soil Characteristics Subsurface Investigation Soil Report Excavation

Objectives, components, applications of Soil The objectives of Soil mechanics science: To determine physical properties of soil. to use the physical information properties for design works of foundations. To improve soil science by researches… Soil mechanics components: Theoretical studying of physical properties. Practical studying of physical properties.

Objectives, components, applications of Soil Engineering applications related to soil mechanics: Foundations: Every foundations of structures, bridges, dams, tunnels,…etc must be established on or under soil. Soil as a structure material: Soil can be used as a filling material and as a construction material in damps, roads, bridges…etc. Excavations and slopes: Under ground structures & brace structure: Such as basements, military structures,…etc

Objectives, components, applications of Soil Problems related to soil works: Soil Stability Problems.مشاكل ثبات التربة Soil Settlement Problems مشاكل هبوط التربة Environmental Related Problems.مشاكل ناجمة عن البيئة Seepage Problems.مشاكل ناجمة عن تسرب المياه Excavation Related Problems. مشاكل ناجمة عن الحفر

Problems related to soil works: C) هبوط التربة ادي الي انهيار جسر.C)

Objectives, components, applications of Soil Soil of Mechanics Definition: It is the science which investigate the properties, behavior of soil as a construction and foundation material. Soil Formation Residual Soil. (granite, basalt, limestone,…etc) Transported Soil. Soil Structure: Coarse grained soil (cohesive less soil) diameter > 0.002 mm (Gravel زلط , sand رمل ….etc) Fine grained soil (cohesive soil)- diameter < 0.002 mm (Clay طين , silt طمي , …etc )

Index Properties of soil Soil Volumes and Weights Relationship:

Index Properties of soil Water content.المحتوي المائي Specific Gravity.الوزن النوعي In-site density.الكثافة الموقعية Relative density. الكثافة النسبية Consistency (Atterberg) limits. حدود القوام (حدود أتربرج) Particle size distribution التوزيع الحبي للحبيبات

Soil Consistency (Atterberg) limits: حدود القوام (حدود أتربرج) Definition of Consistency of soil: is the ability to formation based on the fineness of grain, water content. Consistency of soil cases: Liquid State الحالة السائلة Plastic State الحالة اللدنة Semi-solid state الحالة شبه الصلبة Solid State الحالة الصلبة According to consistency limits soil can be classified

Soil Classification:

1. Soil Classification according to (USA Standard ASTM-ASCE) Clay Silt Sand Gravel Cobbles Boulders Fine Med. Coarse 0.002 0.006 0.02 0.06 0.2 0.6 2 6 20 60 200 (mm) حجر صغير حجر كبير طمي رمل زلط طين

2. Soil Classification according to (Particles Size)

نظام التوحيد القياسي لتصنيف التربة Soil Classification according to (Unified Soil Classification System) نظام التوحيد القياسي لتصنيف التربة

- Peat بقايا نباتات, muck وحل, etc. Types of Soil Organics: very weak soils and retain water; usually removed. - Peat بقايا نباتات, muck وحل, etc.

Soil Characteristics Who needs to know soil characteristics? the structural engineer, to determine how to support the building; the architect, to site the building; the contractor, to estimate the time and cost of the building; the owner, because all the above affect the final price of the land.

Soil Characteristics When do they need to know them? the engineer needs this information prior to the design; the contractor, prior to pricing and planning; the owner, prior to deciding if the project is feasible.

Soil Characteristics How is that knowledge obtained? A visual exploration of the site and adjacent buildings; test pits are dug to visually see the soils below; deeper studies require borings and dynamic penetrometers, samples, laboratory tests and a final report.

Field (site) tests of Soil Static punching test. Shear test. bearing test. Pressure test. Permeability test. Bonding test.

Site report In the following a sample for geotechnical report content from Arab center for engineering studies.

Site Instigation Report Boring: A boring is defined as a cylindrical hole drilled into the ground for the purposes of investigating subsurface conditions, performing field tests, and obtaining soil, rock, or groundwater specimens for testing.

Excavation Common Excavation and Backfill Problems. Unforeseen and differing conditions, such as a higher water table than predicted; unexpected large rock masses, or large boulders; unsuitable materials (undetected garbage pits, old foundations, abandoned utilities, etc.). Weather. The site must have access at all times. Therefore, the contractor may have to maintain all-weather roads. Borrow pits must also be used in all weather conditions. Variable excavation volumes. Every site has some amount excavation.

Excavation In good soil conditions and with shallow foundations, the excavation consists of scraping and stockpiling the organic topsoil. This topsoil will be valuable for all the landscaping needs of the finished project. The good sub-grade material is also scraped and stockpiled to create a compacted mat, or leveling pad, upon which is built the structure’s foundations. Excavation must provide a natural slope so that rain or seepage will drain the water to a corner of the site, where it can be disposed of through pumps. In poor surface soils, deeper excavations may be required to reach a stratum which has adequate bearing capacity. Otherwise, deep foundations (more expensive) may be required.

Excavation Units of Measure: for excavation and backfill: cubic meter for grading: square meter Major Productivity Issues: Type of operation (large sites versus confined spaces) Type of soil conditions (from the best – rock to the worst - clays) Transportation of fill (large distance to borrow pit, or moving within the site) Expected Environmental Conditions (cold winters, hot summers, labor problems)

Field Compaction Methods of field compaction: Sand Cone Method طريقة مخروط الرمل Rubber Balloon Method طريقة البالون المطاطي Nuclear Method الطريقة النووية Equipments of Compaction in the Field: Smooth-wheel rollers مداحل اسطوانية ملساء Pneumatic or rubber-tired rollers مداحل بعجلات مطاطية Sheep foot rollers مداحل أرجل الغنم Vibratory rollers مداحل اهتزازية

Smooth-wheel rollers مداحل اسطوانية ملساء Pneumatic or rubber-tired rollers مداحل بعجلات مطاطية Sheep foot rollers مداحل أرجل الغنم Vibratory rollers مداحل اهتزازية

Questions?!