2.施工方案與方法

2.1 工程概況

2.1.1 工程簡介

2.1.2 氣候條件

本合同段所處地區是沙漠氣候，年降水量12mm。12月至次年3月為冬季，多北風和西北風，白天溫度15度左右，夜晚溫度可降至10度以下。熱季從4月至11月，以東北風為特點，可能帶來一些季風雨，經常引起沙暴，白天溫度一般超過32度。

2.1.3 地形地質

2.1.3.1 地形

2.1.3.2 地質

根據從現場調查過程中獲得的信息及業主提供的地質資料可知，沿線的地質條件如下：

風積沙（大部分可移動）（Qes）：由第四紀的風積沙構成，大部分是可移動的，峰谷相連，波浪起伏。

礫石（Qg2）：由片狀石英礫石、各種比例的石灰石和卵石組成。

Aruma 構造（Ka）：這種材料主要由灰色的，棕黃色和奶油色的石灰石和次要的白云石和粘土組成。

鈣質殼（Qdc）：這種材料由紅褐色，灰色的，棕黃色和黃色的，通常是硬的沙狀的石灰石組成，常常含有夾在里面的底巖碎片。

Umm er Radhuma構造（Tu）：這種構造由灰色的，棕黃色和奶油色的石灰石和含有白云石的石灰石和白云石構成。

沙石、泥灰巖和石灰石（Tsm）：由紅褐色、灰色的泥灰質的沙石，含沙泥灰巖和含沙的石灰石組成。

淤泥和沙石（Qg）：主要由石灰石組成。

Sabkhah 淤積（Qsb）：由泥沙、粘土、含泥的沙組成，通常是含鹽的。

石屑構造（Td）：由粉紅色、白色和灰色的泥灰巖，紅綠橄欖色的粘土和少量沙石組成。

2.1.4 交通條件

本合同段沿線主要公路有：50號、85號、95號、603號、7410號及其它一些公路，路況均較好。大部分結構物集中在線路東段，進場道路較好，西段需要修建較長的施工便道。

2.1.5 材料供應

混凝土：因材料運輸較為困難，攪拌站的資質審查較為繁瑣，施工中盡量采用商品混凝土，沿線可在Abu Hadriyah、An Nuayriyah、Qaryah Alulya、As Suayyirah、Ras Azur、Samdah等地采購商品混凝土，另在KP20+000、KP200+000附近設兩座混凝土攪拌站及相應的材料庫。

砂石料：除部分地段的石質挖方可資利用外，均需遠運。

油料：由沿線的加油站采購。

鋼材：在沿線的城市采購。

水：有條件的地方打井，其它地方采用水車運水。

電：采用自發電。

2 Construction Scheme and Method

2.1 Project Description

2.1.1 Project Scope

There are 3 railway bridges, 11 highway bridges， 359 box culverts, 198 pipe culverts, 44 crossings, 1 station, 14.22million cubic meter railway subgrade excavation, 22.52million cubic meter railway subgrade fill and 6.2million cubic meter highway subgrade fill in CTW100 contract.。

2.1.2 Climate

The contract is in desert climate, annual precipitation is 12m. Winter is from December to March  with north wind and north west wind and the temperater is 15 degree in day time and 10degree less in night time. The hot season is from April to November with north east wind and perhaps some monsoon and season rain and sandstorm. The temperature in day time is usually over 32 degree.

2.1.3 Topography and Geology

2.1.3.1 Topography

2.1.3.2 Geology

According to our site invesitgation and the data provided by Employer, the geology along the line is as following:

Sand dunes（majority is movable）（Qes）：formed with blown sand of Quaternary Period.

Gravel （Qg2）:  formed with slice-shape quartz gravel, limestone and pebble.

Aruma constitution（Ka）: majority formed with gray, brown and creamy limestone, minority with dolomite and clay.

Calcium shell（Qdc）：formed with henna, gray or yellow limestone, usually hard and with rock fragment in it.

Umm er Radhuma constitution（Tu）: This structure is formed with gray, yellow or creamy limestone, limestone with dolomite and dolomite.

Sand, marlite and limestone（Tsm）：formed with henna, gray marly sand, marlite  with sand in it and limestone. 

Sludge and sand（Qg）：mainly formed with limestone.

Sabkhah deposition（Qsb）：formed with sediment, clay and clay bearing sand usually saliferous.

Chips construction（Td）：formed with pink, white and gray marlite, olive clay and little sand.

2.1.4 Transportation

The main highways along the contract are:50#、85#、95#、60#、7410#, etc which are all in good condition. Most of the structures are in the east part of the contract. The access roads are in good condition. In the west part long access roads need to be built.

2.1.5 Resource of Material

Water: Water for living will be transported long distance and water for construction will be gotten by drilling wells or transported long distance.

Power: Self generated

Sand and stone:  Transported long distance besides some excavated material.

Fuel: Purchased at gas station along the line.

Steel: Purchased in cities along the line.