An-Najah National University Faculty Of Engineering Civil Engineering Department Al-Najjar Building Footing Design Systems Alternative Prepared by : Mohammed Yaish Ali Hamdan Mohammed Jabe Submitted to: Dr. Isam Jardaneh

Introduction of Our Project Chapter One presents the introduction of the whole project. Chapter Two presents general types of foundation system Chapter Three presents the structural system of the building that analyzed by two methods which are; tributary area and SAP2000 ver.14 program to find the loads applied on columns and walls.

Chapter Four presents site investigation report including the main aspects of geotechnical prosperities Chapter Five presents design of foundation and which type we choose. The rest chapters present the design of foundations system for the proposed project. In Chapter Six, the design of mat foundation, including mat thickness, settlement, mat reinforcement. while Chapter Seven presents design of pile foundation. Single pile capacity is estimated using several methods, group of piles is found, and pile cap is designed.

Chapter One General Definition of the Project Our project is aim to design the foundation of a commercial building (AL-Najar Building) which consists of ten stories, eight stories above the ground surface & two stories are below the ground surface. The site has an area of 800 m2 and the proposed building will have a plan of about 450m2.

Chapter Two Review Of Engineering Foundations It’s function is to transfer the load of the structure to the soil on which it’s resting.

Types of Foundation There are two main types of foundations: 1) Shallow Foundations Isolated, combined, mat (raft) foundations 2) Deep Foundations Piles foundation

Depending on the structure and soil Characteristics, type of foundation is used: 1-Raft or mat foundation

2-Pile foundation

Chapter Three Structural System The main objective of this chapter is to find the loads applied on columns using two methods which are: Tributary area method and analysis using software called SAP14.

Loads applied on columns

Chapter Four Site Investigation Report Summary of Test’s Results

The site consists of layers of sedimentary dark brownish silty clay of high plasticity soil with pebbles. Unit Weigh = 17 KN/ m 2 Cohesion = 90 KN/m 2 Angle of Internal Friction = 0 The allowable bearing capacity will be taken 1.5 Kg/cm 2 (150 KN/m 2 ).

CHAPTER FIVE DESIGN OF FOUNDATIONS First of all we will check if Isolated footing can be designed, if we find that this method can't be used, then we will design the Mat Foundation and Pile Foundation. In our project the space between column not enough to design single foundation, so we will design the Mat foundations in chapter six.

Overlapping: Figure below demonstrates the overlapping of the stress for the two footings. Calculations: σ1=(5030)/( )² = KN/m² σ2=(2010)/( )² = 174 KN/m² = 367 KN/m² > 150 KN/m² This value is not safe (failure). So, we can’t design Isolated Footing.

CHAPTER SIX MAT FOUNDATIONS Mat foundations are used to spread the load from a structure over a large area, normally the entire area of the structure. To design Mat Foundations, the depth of the mat has to be found from punching shear equation manually. Then, the maximum moment in (X) and (Y) directions, area of steel and settlement are found from SAP.

To find the depth of foundation, the punching shear equation is used. When Bc > 2 When Bc < 2

After achieved the previous two equation on critical column we take the maximum thickness equals 90 cm. Then the total thickness of the mat equals: h = d + cover h = = 100 cm

3D – Mat Foundation

Settlement The settlement of each column was taken from SAP14 and we find that the values is 1.7 cm and this value is acceptable.

Maximum moment in (X) and (Y)directions The values of maximum moment in (X),(Y) directions are taken from SAP14. The figures below show the moment in (X),(Y) direction.

Summary Of Reinforcement in X-Direction

Summary Of Reinforcement in Y-Direction

CHAPTER SEVEN PILES FOUNDATIONS Design of Piles: A computer program called AllPiles is used to prepare allowable bearing capacity with each pile length and diameter, table below shown the result:

Two types of piles are selected in the design of pile foundation in this project, which are shown in the following table: Table below shows the allowable applied load and the No. of piles with cap’s dimensions that each group of column has.

Reinforcement Details of Piles The equations below is used to determine the area of steel :

Example Of Design Cap

The allowable applied load and the number of piles with cap’s dimensions that each group of column has and the area of steel for all cap of the pile are shown in the following table: