3.11.6.4 Live Load Surcharge (LS)

3.11.6.4 Live Load Surcharge (LS)

 

The values for heq given in Tables 1 and 2 are generally greater than the traditional 610 mm of earth load historically used in the AASHTO specifications, but less than those prescribed in previous editions (i.e., before 1998) of this specification.  

 

The traditional value corresponds to a 90 000-N single unit truck formerly known as an H10 truck, Peck et al. (1974). 
This partially explains the increase in heq in previous editions of this specification.

Subsequent analyses, i.e., Kim and Barker (1998) show the importance of the   direction of traffic, i.e., parallel for a wall and perpendicular for an abutment on the magnitude of heq.

The magnitude of  heq is greater for an abutment than  for a wall due to the proximity and  closer spacing of wheel loads to the back of an abutment compared to a wall.

The backface of the wall should be taken as the pressure surface being considered. Refer to Article C11.5.5 for application of surcharge pressures on retaining walls.

 

표 1 및 2에 주어진 heq 값은 일반적으로 AASHTO 사양에서 역사적으로 사용된 기존의 610mm 접지 하중보다 크지만 이 사양의 이전 버전(즉, 1998년 이전)에 규정된 것보다 작습니다.

전통적인 값은 이전에 H10 트럭으로 알려진 90,000-N 단일 단위 트럭에 해당합니다. Peck et al. (1974).

이것은 이 사양의 이전 버전에서 heq의 증가를 부분적으로 설명합니다.


후속 분석, 즉 Kim과 Barker(1998)는 교통 방향의 중요성을 보여줍니다.

heq의 크기는 벽에 비해 접합부의 뒤쪽에 대한 바퀴 하중의 근접성 및 더 가까운 간격으로 인해 벽보다 접합부에 대해 더 큽니다.

벽의 뒷면은 고려 중인 압력 표면으로 간주해야 합니다. 옹벽에 대한 추가 압력 적용에 대해서는 C11.5.5조를 참조하십시오.